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intercooler aviation Related Articles

Top Rank: What are the worst-selling cars in Malaysia?

was powered by a 1.1-litre straight-4 engine produced by a joint venture between Mitsubishi, Harbin Aviation

How did Tun M’s Proton Perdana ended up gathering dust in the UK?

The town was home to one of the earliest British aviation companies of the same name and Bristol Cars

Tom's tunes 2020 Toyota GR Supra and Toyota Century

The Supra gets a new turbo, intercooler and an ECU tweak among other mods to bump the power up from 335

Tiny turbo engines: good or bad?

Without an intercooler, hot air is pumped into the engine.

The brilliant 2020 Toyota GR Yaris in Malaysia - not for those with outdated ideas of cars

incorporating the signature GR "functional matrix" design - feeds air into the radiator, intercooler

Owner Review: The heritage hot hatch - My Volkswagen Golf GTI Mk. 7

air filter with snow grate removal from the stock airbox Supercircuit downpipe Custom catback Majesty intercooler

The all-new 2020 Nissan Almera’s engine has something lifted from the R35 GT-R!

, the all-new Nissan Almera also features an electronic wastegate that reduces turbo lag and an air intercooler

Did you know that Geely has a flying car that works?

More importantly, it complies with both automotive and aviation safety regulations.

The Daihatsu Rocky is more expensive than the Toyota Raize, why?

The cooler mounted on the front of this particular Daihatsu Thor is likely an intercooler for a turbocharged

Owner Review: My Perodua Kelisa - Great car for those who are thinking of getting their first car

engine that I’m using too, it has a funnel which directs the air the scoop brings directly to its intercooler

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New MD appointed at Michelin for Malaysia, Singapore and Brunei

as a Corporate Development Manager.In the span of 6 years, he moved up to Zone Director of Michelin Aviation

1994 Renault Espace F1 - 820 PS and 317 km/h in a 7-seater

Matra-Simca Bagheera "Courrèges" Back then, Renault was working with Matra (Mécanique Aviation

6-month moratorium: Dear banks, you need to work on your public relations

them.Yes, the financial sector is heavily regulated so it limits how a message can be conveyed, but the aviation

The first flying car in the world is now road legal in Europe, but its still grounded

tests are done will the company be allowed to carry out the 150 hours of flight testing to achieve its aviation

Mod My Car: Shopping for a niche 15-year old car - My Subaru Impreza WRX STI

and insurance are under RM2.5k/year and I’ve only had to replace the air-con cooling coil and intercooler

MPVs aren't selling here, but how is the Proton Exora still growing in sales 11 years on?

This is due to all the extra components such as the turbocharger and intercooler systems, and necessary

NA vs Turbo: Why they say there’s no replacement for displacement

and out as exhaust gas to spool the turbo, then it draws more air to which it has to be cooled by the intercooler

Spyshot: Daihatsu Thor seen in Malaysia, what is it doing here?

we gathered, the cooler mounted on the front of this particular Daihatsu Thor is more likely to an intercooler

2020 Toyota GR Yaris launched in Japan – Smaller, more special rival to the Civic Type R

driving force system through a multi-plate clutch.The RZ variant is also equipped with an air-cooled intercooler

Owner Review: My journey in Australia - Mercedes-AMG GLC43 long-term review from WapCar reader

car and placed the customary red bow on the hood, with a full tank of 98-octane gasoline, Permagard aviation-grade

15 years ago, this Korean car invented the SUV-coupe, not BMW!

Power came from a 2.0 XDi 200 XVT common rail turbo intercooler diesel engine and buyers could get a

intercooler aviation Post Review

PIPER AEROSTAR 601P INTERCOOLER PLUMBING P/N. 98-10015-1 https://t.co/vTAM9OKGEG eBay https://t.co/ze8rGSDDLB

eBay: 1985 Mooney M20K Intercooler, Merlyn, GTN750, GTX345 ADSB Compliant https://t.co/pLZXzI5EhD #aircraft #aviation https://t.co/bVLD9NS0q4

I was looking at the Rotax 915is for my #kitfox but discovered Edge Performance & Stol Creek Aviation. Leaning towards the EP914TI which is a Rotax 914 modified w/ fuel injection intercooler etc 126HP 2000TBO weighs less and can be tuned easily. #avgeek #aviation #homebuilt https://t.co/rZNQhzW2pB

The next big thing in aviation: What's next for Aviation in 2016 https://t.co/xPgVcOChhA

@NMahesh77 @c_mperman @CobraBall3 @AusterityAirli1 @Dunibear @clark_aviation @julieinthesky @AvHistorian @KeysRetired @JBezosky 2/ Looking at the drawing, it provides the air supply to the intercooler system.

ANN's Daily Aero-Term (09.12.14): Intercooler http://t.co/ToNvvpBXkA #aviation #news

Continuing a theme...bar and plate turbo intercooler using an aviation-grade core. Brilliant… https://t.co/cAkFGo2zGt

Boeing B-29 Intercooler Flap Position Indicator with Free Priority Mail $49.95 http://t.co/adqLFwdVgA #Aviation #Part

@NMahesh77 @real_aghasee One is an oil cooling radiator, the other is the supercharger intercooler.

@clark_aviation Let's see if I've got this right - so instead of each Merlin having its own supercharger, here it has a centralised blower, with intercooler, powered by a 5th Merlin, solely to provide forced induction to all 4 wing-mounted engines?

intercooler aviation Q&A Review

During WW2, why did it take Britain an entire year to find a worthy counter to the FW-190?

During WW2, why did it take Britain an entire year to find a worthy counter to the FW-190? Introduction of FW190; August 1941 Introduction of MK IX Spitfire; June 1942 The Wiki article on later model Spitfires seems pretty comprehensive. Supermarine Spitfire (late Merlin-powered variants) - Wikipedia The MkIX had the Merlin 61/63/66 and 70 series engines, with a two-stage, two-speed supercharger with intercooler. Because of this, the Merlin was longer. This required a longer nose (an extra 6 inches body length, and 750lbs weight with the C of G changes that the changes would entail…) The intercooler required an additional radiator. The MKV and the MKIX have different systems. Mark V Later mark Spitfire (this is a MKXVI, but it clearly shows the additional radiator under the port wing) Aviation Photo Search | Airliners.net A different Carburettor intake was used. A "Heywood" air compressor was fitted on the starboard upper engine cowling. https://picclick.co.uk/Vintage-Rolls-Royce-Merlin-Compressor-as-fitted-to-222991196627.html The exhaust ports were changed from three to six parts. The MKIX employed a four bladed propeller. All in all, considering the MKIX was intended to be a stop-gap to take on the FW190, (while waiting for the MKVIII to come on line) it had quite a lot of ‘evolutionary’ changes to take in to consideration. (The MKIX was very good, accounting for around 40% of Spitfire production. In October 1944, 401 Sqn Spitfire MKIXs were the first allied aircraft to shoot down a Me262. The Mark stayed in RAF service until 1955!)

How did the US high octane aviation fuel contribute in WW2?

This is a rather lengthy write-up on the development of gasoline/petrol and its octane number. Early aviation piston engines encountered a problem which they first attributed to overheating - the engine would develop good horsepower for a few minutes then performance would reduce as it got hot. Even the Wright Brothers encountered this as their first engine produced 12hp but as it continued to run and got hot the power reduced to about 9hp. The fuel they used was later identified to be about 38 octane, as we measure it today, so detonation/knocking was the most likely cause. Their second engine was slightly increased in capacity (Bore up from 4" to 4 1/8") and they reduced the compression ratio from 4.4 to 4.0 and this stopped the "overheating" problem, despite it then producing 21 hp and running at higher rpm than the first engine - up from 1340rpm to 1500rpm. So there is a strong possibility that their first engine was indeed suffering from detonation as it got hot. The noise from the open exhausts in early engines, plus the propellor noise, meant that they could not hear detonation when it occurred, and no one knew how to measure detonation if it was occurring. But some gasoline from different refineries performed better than others. (Edit: A little extra info. During WW1, the British ordered their fuel by specific gravity, with the lightest grade going to aircraft as it seemed to give the best performance. Cars and trucks got the next "grade" and when Harry Ricardo was asked to develop a new engine for the improved Mark4 tanks (tanks were originally developed by Squadron 21 of the Royal Navy so they could move larger guns up to the front and use the tanks to straddle and clear out German trenches - hence the side mounted guns) and they gave him samples of the fuel he had to use. It was more like Kerosine than gasoline/petrol, and the highest compression ratio it could use without knocking/detonation was 3.5:1. But that engine was a huge success because it would burn almost any available fuel, and was used in coastal patrol boats and on truck mounted generators for the Army. 8000 tanks and 6000 other boats/vehicles used it during WW1. Ricardo asked his contact in Shell to provide samples of ALL fuels used by the British and one in particular performed much better than the others in his home-built world first dedicated variable compression test engine. This particular fuel was a ring-in…not ordered by the Brits … and thousands of tons of it were burnt as waste in the oil fields of Indonesia. Years later it was estimated to have an octane rating of about 70, much better than anything else available at that time. ) This British combustion specialist Harry (later Sir Harry) Ricardo developed the world's first variable compression engine In 1918, with a "knock" sensor, to test different fuels, and he developed a concept called the Highest Useful Compression Ratio. He suggested that detonation was a form of uncontrolled combustion, occurred DURING the combustion event AFTER the spark. , where others thought it was ignition BEFORE the spark - pre-ignition. Thomas Midgely in the USA confirmed Ricardo's view in 1922 during his investigations into adding Tetra Ethyl Lead to gasoline to improve its anti-knock capacity. Midgley had a similar test engine, with a window in the head, so he could film the combustion process. In 1927 Graham Edgar, working for the Ethyl Company (makers of TEL) in the USA developed the Octane rating system we use today. He discovered that a pure compound called n-Heptane had a terrible tendency to knock/detonate but a particular isomer of octane called iso-octane had an outstanding anti-knock capacity (he also looked at Toluene, xylene and other compounds). Since the two chemicals iso-octane and n-Heptane had similar volatility and other physical properties, various mixtures of the two would not change the test results, so he assigned n-Heptane the number Zero, and iso-octane the number 100. Now any fuel could be compared to a mixture of those two compounds to determine its knock resistance. The test fuel did not have to contain either of those chemicals, it just needed the knock resistance of a given mixture of the two. So from about 1930 onwards most gasoline/petrol sold had a stated octane rating. For cars it was usually in the range of 70–80. By 1930 the usual standard for aviation gasoline was 87 octane (and containing TEL of course), measured using the harsher of the two tests used…the newly developed Motor Octane Number - MON - test. (In general, the easier test Research Octane Number - RON - was used for auto octane numbers). The MON test gives a lower number than the RON test for the SAME fuel. These days everywhere except the Americas uses the RON for auto octane numbers. The USA, Brazil and a few other countries there uses an average of RON and MON numbers and calls it the anti-knock index - AKI. So for example 87 AKI in the USA is equivalent to 91 RON in most other countries. Back to Aviation Gasoline… Most aviation gasoline for Britain during the 1930s came from the USA….Esso in Baton Rouge, Shell in Houston, and Esso in Aruba. When Rolls Royce developed the Merlin engine in the mid 1930s, it was proposed to produce around 1000 hp on the commonly available 87 octane aviation gasoline. But even as early as 1935 there were efforts to produce a 100 octane gasoline as they knew engines could produce more power with increased supercharging (which increased the effective compression of the engine). A man named Stanley Hooker joined Rolls Royce 1938. He was called a mathematician but his specialty was fluid dynamics (how gases and liquids flow) and his first job was redesigning the supercharger for the Merlin engine - changing the impellor blade design and the air inlet and ducting to smooth airflow into the supercharger. This resulted in an instant increase to over 1200 hp in the engine, and as 100–130 octane fuel became available in early 1940, the engine was then able to produce over 1300 hp. This became the Merlin 45, fitted to the Spitfire V, just in time for the Battle of Britain during that summer. The increased horsepower of the newer Merlins provided a much higher rate of climb and higher top speeds so the Spits, with their better performance (particularly at higher altitudes) and Radar to direct them so they had more fighting time, were better able to defend against the Germans who at that time were using only 87 octane gasoline. Germany did have limited supplies of 100–130 octane (some reports say only 95 octane) during the last years of WW2 but used mostly the lower octane fuel. (Stanley Hooker went on to develop the first Whittle Jet engines into the RR range of jet engines and eventually resurrected RR from their bankruptcy over the development of the RB211 turbo fan engine). Just for info, the British understood that a rich mixture did not detonate as much as a leaner mixture so all aviation fuels in the west were given a two-number rating. The lower number was the lean burn cruise octane rating and the higher number was the full rich max power octane rating. Detonation is a heat-related phenomena. Increasing the compression ratio, or adding supercharging, increases the amount of compression heat in the engine, and this heat, combined with the heat of combustion, can cause some components of gasoline/petrol to break down during the very short combustion process (2–3 thousandths of a second) and self ignite before the flame front completes its fast steady burn. The resulting shockwave can destroy an engine if allowed to continue. Higher octane gasoline/petrol is more stable under heat and pressure and will allow the flame front to complete its steady burn without self igniting. The development of higher octane fuels continued as Stanley Hooker worked on the next step in the development of the Merlin engine - a two stage, two speed supercharger with a water intercooler between the first and second stage (correction - after the two super chargers, before the inlet manifold). This cooling reduced the inlet temperature by at least 25 F (reducing any tendency to detonate after ignition) and with the use of the new 115–145 (Sometimes also called 115–150) octane gasoline (containing over 1.3 gm of TEL per litre), the 1942 Merlin 61 had over 1600 hp, and some special models up to 2000hp. The Germans did have some 95 or 100 octane gasoline (the US had sold them with the know-how to produce TEL prior to WW2), but supplies were very limited and they therefore designed many engines with higher capacities to try to get similar horsepower ratings on the lower octane gasoline - for example the excellent DB 601 engine in the Bf109 was 34 litres where the Merlin was only 27 litres, but produced much more power. The availability of large supplies of 115-145 octane gasoline gave the allies a huge advantage in aero engine performance which the Axis powers could not quite match, even though they developed water/methanol injection and Nitrous Oxide injection for short duration increased performance. The availability of 115–145 octane gasoline after WW2 also allowed for the rapid expansion of the airline business and production of aviation gasoline skyrocketed for several years, then started to diminish as jet engines became more prevalent. There was an increase during the blockade of Berlin by the USSR when Berlin was supplied with almost everything they needed by Air frieght, and again during the Korean War as there were still many piston engined aircraft used at that time (Mustangs and Skyraiders for example), but since then the use of aviation gasoline has diminished markedly. Eventually 115–145 octane was dropped, apart from small batches for Reno race planes and the like, and 100LL (100–130 octane LowLead) has become the highest octane readily available aviation gasoline. I was speaking with the pilot of one of only two flying Spitfires in Australia (at Temora NSW) just a few months ago. Their Mark V111 Spit has a 1600hp Packard built Merlin, and it runs just fine on 100LL. But they cannot "break the wire" on the throttle to use war emergency power - thus limiting the supercharger boost to prevent any detonation. There are continuing attempts to produce a suitable unleaded high octane aviation gasoline to replace 100LL, but its difficult. Many of the hydrocarbons with the highest natural octane numbers are often the most volatile compounds, and aviation gasoline needs to be a low volatility fuel so it does not form gas bubbles in fuel lines as the aircraft climbs up into the less dense atmosphere, so at the moment, low volatility 100 LL containing 0.56 gm/litre of TEL is still the best compromise. There is still roughly 100 tonnes of TEL made per year for "doping" aviation gasoline - it's made in only one place in the world - a factory in the UK.

Was the American P-47 Thunderbolt a formidable plane during WWII?

The P-47 Thunderbolt was very likely the best high-altitude fighter of the war. It was designed around a highly-efficient turbo supercharging system that ducted air for the turbine and intercooler under the cockpit. This deep fuselage gave the aircraft a somewhat portly appearance but endowed great ruggedness in addition to the air flow properties. Because of its size and aerodynamic properties, the P-47 could out-dive any fighter in the world and - equipped with eight .50 caliber machine guns - was absolutely devastating when it caught up with an enemy plane below it. It was ideal top cover for 8th AF bombers. Many a Luftwaffe fighter pilot met his end when jumped by P-47s. It is very sobering to watch P-47 gun camera films of Fw-190s being disintegrated by fire from these weapons. The aircraft suffered many teething troubles and didn’t really mature until the D-model, which was produced in greater numbers than any other subtype American fighter. It was very fast but climb rate suffered until paddle-blade props were introduced. The M model was faster than a P-51D by 33 mph and the aircraft was surprisingly maneuverable for its size, with a very respectable rate of roll. The major shortcoming was range, which was progressively improved through drop-tank adaptations and ultimately the N-model, which had P-51-like range. In addition to the escort role, the P-47 excelled at ground attack. Great firepower coupled with outstanding ruggedness made it ideal for this job. Units were moved to advanced airfields in France after the invasion and from these primitive strips it shared the job of close support with the nearly equally-formidable Hawker Typhoon. The P-47 was the most rugged fighter of the war - and that is saying something when the F6F and F4U are comparators. Many a pilot owed his life to the rugged construction saving him in a forced landing. And - this is a critical factor - the P & W R-2800 engine that powered it was famous for rugged reliability. P-47s - nicknamed “jugs” for their shape - flew home with “jugs” (engine cylinders) completely blown off. This was an amazing combination of airframe and engine. The P-47 is one of the immortal aircraft that fought and won the war. Now it is a delight to see and hear at airshows. But during the war it epitomized the overarching power of U.S. aviation and the industrial base behind it. It was the larger-than-life gunfighter - tough as nails, powerful, deadly, and rawboned as the American west. But it was given its basic design by a Russian émigré on a train from Washington to New York’s Long Island when returning from a meeting with USAAF officials. It served in all theaters of the war and could have done even more if it had been sent to Korea. It could have been - but that is another story. The P-47 is iconic, a living reminder of a time when brute power and force was applied for a great and good cause - and prevailed. The spirit of the P-47 is wholly American and wholly victorious. Of all the many great aircraft of the war this one lies at apex of that metaphorical “Mt. Olympus” along with such icons as the B-17 and Spitfire. It was a true thoroughbred.

How would the Corsair have compared with any of the WW2 fighters in the European Theater?

I have often wondered about the idea presented myself. The Corsair certainly would have been highly competitive over Europe. It is well to recall that the first U.S. fighter to exceed 400 mph was the Corsair prototype. Evolved versions of the design were capable of 470 mph and clearly in terms of range, maneuverability, fire power, and ruggedness the aircraft had an outstanding performance overall. In many of these categories it compares well with such thoroughbreds as the P-47 Thunderbolt or FW-190. The only area of question is altitude performance. In this regard it may have been found a bit wanting as combat in the ETO evolved. For example, the P-38 was limited in northern Europe due to the effects on its supercharger system of the damp cold prevailing there; and the mechanical supercharger system used in most Corsairs were not as efficient at high altitude compared to the turbocharger systems of the Thunderbolt or possibly even the mechanical supercharger system on the Mustang. Late model Corsairs, having two-stage, two-speed superchargers with massive intercoolers likely would have been more competitive - but they came too late for combat in the war. Despite this limitation, while there can never be a realistic answer to this question and the entire idea is speculative, given the choice I wouldn’t want to be a Bf-109 pilot with a Corsair on my tail. Nor would I like to be a ground combatant subjected to the sound of “whistling death.” Arguably one of the greatest piston engine warplanes ever built - and the last piston-powered fighter produced in the U.S. - the Corsair holds a first-class place in aviation history. Too bad it didn’t compete in Europe, where it may have added yet another garland to its laurels. But it wasn’t given the opportunity so we aviation history buffs must be content with another venture into the world of fantasy.

What one development in the pre-WWII aviation industry would have set the USA up for a more successful beginning to the war?

Learning the nuances of two speed two stage supercharging, turbocharging, intercooling, after cooling, and the effects of higher octane and octane additives on an engine. These advances improved performance of airplane engines at higher altitudes and almost doubled the horsepower rating at all altitudes. This is not one development, yet they all go hand in hand.

What were British planes’ weaknesses in WW2?

Not many, but a few… Arguably the main aircraft engine the RAF relied on was the: The Rolls Royce V-12 27-litres, (1,650 cu in) capacity Merlin. (Named after the bird, not the wizard, BTW.) A bit simpler, easier to maintain, easier to build than its rival, the German Daimler Benz DB 601/5s which made it a far better war engine…a wonder of tight tolerances and high efficiency, and one of my favourite WWII engines that I rate as tied for #3 with the Allison V-1710 and after the two best of the war, #1. the Pratt & Whitney R-2800 air-cooled double-row radial Double Wasp, and #2. the BMW 801 air-cooled radial. First models made 800 HP, but power was increased rapidly to 1,150 HP, then 1,480 then 1,600 by the end of the war, doubling the HP! Through my work I met and was befriended by Jeffrey Quill, top Spitfire test pilot during WWII after “Mutt” Summers left. He constantly praised Rolls Royce for their engines, (and had a special fondness for the Griffon engine, esp. and I was honoured to do a pen and ink commission of his first flight in the Griffon-powered Spitfire prototype, of which you can see a print of here: ) He said with only a bit of hyperbole, that the Rolls engineers and designers basically never slept for six years, constantly updating, strengthening, improving, always aware that thousands of lives depended on even small adjustments to their amazing engines. Anyone who has read me here knows that I’m a huge fan of the just-mentioned air-cooled radials like the Pratt & Whitney R 2800 and BMW 801, as they are far stronger/more durable in a combat setting, and that the water-cooled engines, efficient and narrow as they are, were far inferior as a combat engine as one, tiny piece of high velocity metal piercing its huge unarmoured water-cooling system (“Golden BB,”) can put it out of action, but I have a fondness for the Merlin. Why do I think it’s the best vs great competition like the German Daimler Benz DB 601/5 inverted V-12 and the American Allison V-12? Here’s a couple of reasons: Supermarine Spitfire… Hawker Hurricane… Avro Lancaster… de Havilland Mosquito… and the Packard-built Merlin powered North American P-51 Mustang for fun… The Merlin was significantly smaller in displacement, (1,650 cu in), then the German Damlier Benz DB 601, (2,068.7 cu in) and DB 605, (2,176 in,) but got better and then later in the war, far better performance out of its capacity and though intricate, was not as complicated or as expensive and as hard to manufacture as the DB 605. 149,659 Merlins were made vs 19,000 Db 601s and 42,400 DB 605s. A big part of the Merlin’s superior performance with smaller displacement was the far higher octane fuel that was coming from America, just in time for the Battle of Britain, that allowed increased manifold pressures and significantly more power. A must-read is about Eugene Houdry and Alex Golden Oblad, two unsung heroes of the battle of Britain and WWII itself, and their work on a chemical catalyst process for the Sun Oil Company, now Sunoco, which converted almost useless crude oil/sludge into 100-octane fuel that America gave England to replace the standard European 87 octane fuel just before the Battle of Britain and helped increased the Spitfire's speed by 25 mph at sea level by 34 mph at 10,000 feet, a not inconsiderable advantage against the Bf 109s. (In the early 1930s Eugene Houdry collaborated with two American oil companies, Socony Vacuum and Sun Oil, (later Sunoco,) to build pilot plants. Oil companies that did not want to resort to the new additive tetraethyl lead were eagerly looking for other means to increase octane levels in gasoline. In 1937 Sun Oil opened a full-scale “Houdry unit” at its refinery in Marcus Hook, Pennsylvania, to produce high-octane Nu-Blue Sunoco gasoline. By 1942, 14 Houdry fixed-bed catalytic units were bearing the unanticipated burden of producing high-octane aviation gasoline for the armed forces.) Quick fixes of problems, (for instance, the Spitfire’s fuel cut-out problems during neg-G dives with its carb… …and then the fix: Single-stage, single-speed gearbox: Merlin I to III, XII, 30, 40, and 50 series (1937–1942). To: Single-stage, two-speed gearbox: experimental Merlin X (1938), production Merlin XX (1940–1945). To: Two-stage, two-speed gearbox with intercooler (,Intercooler - Wikipedia,): mainly Merlin 60, 70, and 80 series (1942–1946.) With the two-stage, two-speed model one supercharger was feeding the other supercharger that was in turn feeding the engine. The German 605 couldn't match this and not until the very late and very few Messerschmidt Bf 109K models with the water-methane injection… …could the Bf 109s even try to match the speed of the Spitfire, P-51s and P-47s. The Merlin engine achieved mythical status during the Second World War when combined with key aircraft such as the Hurricane, Spitfire, Mosquito, Lancaster and the P-51 Mustang. Below: animated videos of the insides of a Merlin. So what’s the problem/weakness? What I stated above. Vulnerable Liquid-cooling and it was a bit “busy”… …and perhaps a bit complicated and maintenance-heavy. (The Allison V-1710 V-12 had aprox. 7,000 parts vs the Merlin’s aprox. 11,000 parts, and both made pretty comparable HP, although the number of *moving* parts are more equal. In the USAAF Statistical Digest… …Specifically: and: …the numbers showed that the average man-hours expended per major engine overhauls in continental US-based maintenance depots from July 1943 through August 1945 on a monthly basis, showed the Packard Merlin V-1650 required an average of 320.2 man-hours per overhaul with a high of 592 hours and a low of 190 hours. And During the same period the Allison V-1710 required an average of 191.5 man-hours per overhaul with a high of 376 hours and a low of 117 hours. But It’s been years and my memory fades so don’t quote me, for God’s sake.) 27-litres (1,650 cu in), eventually at its pinnacle, equipped with a two-step, two stage supercharger, (actually one supercharger supplying mixture to the “engine” and one supplying…the other supercharger! Boost pressure automatically linked to the throttle, coolant-air aftercooler between the second stage and the engine.) For most of the war it made aprox. 1,500 HP. A superlative engine…except in my mind, for combat. I had the chance to help work on a Packard-built Merlin’s camshaft exchange some years ago, incredible!…it came in a long, narrow black box like a chromed Balabushka cue stick…or Excalibur…nestled in a bed of crushed blue velvet…a jewel! Its main problem, a big one, the same as every other combat liquid-cooled design including the Allisons and Daimler Benz’s DB 601/5s: any piece of high velocity metal, (or the proverbial ”Golden BB”) in the unarmored and incredibly vulnerable radiator(s), water jackets, water pump, header tanks, hoses and fittings that were in much of the front third of the Spitfire/ Mustang/Bf 109/P-40 fuselage, and it was, suddenly and with a disconcerting CLANG!, an “air-cooled” design and had the flying characteristics of a brick… In the images below, specifically for a Packard Merlin P-51 and a DB 601, check out the liquid-cooled vulnerability of the Packard Merlin with basically everything you see illustrated totally unarmored and able to be pierced by any piece of high velocity metal, no matter how small: the Header Engine Tank, almost the entire engine with its Water Jackets exactly like your family car, Engine Coolant and Aftercooler System Pumps, all of the large hoses and fittings, back to the huge Coolant Radiator and Aftercooler Radiator in the very vulnerable belly. A bullet, cannon shell, or even a piece of high velocity metal the size of a fingernail clipping piercing any of this simple sheet metal and the coolant is expelled under pressure, the heat goes up QUICKLY and within 5 minutes your liquid-cooled engine is now “air-cooled”, the metal parts all expand beyond design and basically fuse/sieze and you *are* going down… Below: Another angle…basically the entire front of the P-51 (or P-40, Hurricane, Spitfire or Bf 109) are very vulnerable spots. So why use a liquid-cooled engine? A wonderful engine for narrowness in the fuselage allowing great aerodynamics, great Horse Power per cubic inch of displacement, superior fuel efficiency and good milage, but its trade off, and there are always trade-offs, is its great vulnerability. This Is A Fact, kids: “Engine cooling 101.” Not the ideal engine in an intense combat setting where high velocity “shrapnel sh*t storm” metal is flying everywhere was the norm. In a Mosquito or Lancaster with multiple engines, a catastrophic engine hit was survivable…but the single-engined Merlin-powered Spitfires, Hurricanes and Mustangs were not so fortunate. (Above: Spitfire cutaway. The entire front of the Spitfire with its coolant system , oil tank and header tank, not to mention hoses and fittings and water pump-all unarmored, and vulnerable to a single, tiny lire of high velocity metal. (Below: See of the Spitfire’s coolant system-all unarmored.) (Above: Bf 109F’s coolant system. All unarmored.) (Above: P-51 Merlin’s header tank-unarmored.) (Above: Bf 109 G’s header tank, water jackets, oil coolers, radiators, water pumps, hoses and fittings, etc. -all unarmored.) Also to mention, the Spitfire had a very narrow landing gear, (although not quite with as criminally insane “geometry” as the terrible Bf 109 that killed thousands of young, green pilots, mostly later in the war on landing accidents, esp. ground looping from the narrow gear!) Taxiing, take-off and esp. landing accidents were unfortunately common. (Above: Very narrow gear made landing, esp for a tired, wounded or green Spitfire pilot, problematic.) (Above: Terrbile gear. Weak, spindly, and Willy *knew* it was dangerous and never changed it to keep his, admittedly, beautiful wing intact, dooming thousands of green German pilots to injury or death.) (Above: the far superior and wider Fw 190 gear. Excellent.) (Above: And Beautiful P-51 gear.) (Above: And fantastic P-47 gear.) Final nit: their anaemic .303 machine guns were not up to the task, although their wonderful 20mm Hispano cannons were. Below, .303 Brownings: (ABOVE: PRETTY GRAPHIC! the .303’s couldn't cut it, even though the Bf 109s were very fragile.) Thanks for reading.

What properties of graphene make it useful for what type of technologies?

Richard has great list. I will talk about three uses which I think can be near term - meaning 4 months to 2 years. 1. One short term opportunity for graphene is replacing ITO (Indium Tin Oxide) electrodes in LCD displays. The graphene does not need be in a coherent sheet to work, piles of graphene rectangles that touch in enough places will work. So this can be done with some kind of shake and bake and a solvent. ,Transparent Conducting Electrodes 2. The second use is single layer graphene for much higher frequency transistors, well over 60 GHz. This opens up a lot of bandwidth for short range uses, like WiFi and moving HDTV signals around the home. Only a few transistors are needed to do this, and those can have a high initial cost. If they were made in Asia, they could even be hand made and still work economically for a few years. The economic incentive for higher frequencies is larger, and only a few devices are needed per system. ,Graphene Transistors 3. The third early application is a bulk use for the high thermal conductivity. Already, bulk nanotubes are being used as an interface from an RF transistor to a heat sink. In addition to electronic uses, such as heat sinks for transistors and laser diodes, bulk graphene will be used as heat conductors in heat exchangers, along with some of the newer aerogels (as heat insulators). In additional to the high heat conductivity, the heat conductivity for the mass is very high. Applications would be turbocharger intercoolers for aviation and ground vehicle engines, and various pre-heat paths in conventional power plants. Being a bulk application, this should happen quickly. ,Bulk thermal conduction

Was the Messerschmitt BF 109 the best plane the Germans had in World War Two?

NOTE: ALL MY ANSWERS ARE FREE CONTENT! No. It was a fantastic design for the ‘30’s but got old quick in the ‘40’s and the world of fast-developing military technological advancements from the REAL “Mother of Necessity”: War. The FW 190 was the best Luftwaffe aircraft, (with a special tip of my hat to the Ju 88!.) But some thoughts about the Bf 109, NOT a great aircraft after 1941… (Above: The #1 killer in military aviation history that shot down more enemy aircraft than any other, but… ) (Above: Fw 190, greatest German fighter of WWII: Tough, fast, great handling, hard hitting. Versatile: great air-to-air, great ground attack, great photo-recon, good escort fighter, it could do it all…except It’s one weakness: exceptional high altitude performance above 20,000 feet which was addressed with the long nosed “D” “Dora” model with the in-line Jumo 213 engine.) (Above: Only at high altitude with it’s 2 stage supercharger, did the Bf 109 have an advantage over the Fw 190, but the long-nosed ‘D’ version rectified that.) But I will share a couple of insights from my 25 years as a professional military artist where I worked in the WWII Aircraft/AFV world that might be interesting as I personally knew Jeffrey Quill, the top Spitfire test pilot, “Corky” Meyer, Grumman’s top test pilot and America’s top civilian test pilot and the #3 ace of all time, Bf 109 pilot G,ü,nther Rall. If we are talking air to air victories, then it isn’t even close, the Bf 109 was the greatest killer in history: “The Bf 109 was credited with more aerial kills than any other aircraft.”-Wiki “Moreover, the ubiquitous Me-109 was credited with shooting down more enemy aircraft and producing more aces than any single fighter in the annals of aerial warfare.”-Historynet. The Messerschmidt Bf 109, flying for many different airforces from 1936 and soldiering on till the mid-1960’s, with a possible tally some say might reach as high as 20,000+ Allied aircraft destroyed. How high is very difficult to say as numbers vary widely just as accurate Luftwaffe losses also vary from different sources and the Soviet Union/Russia has always been very evasive about any kind of WWII loses, men or equipment. Food for thought though: just the top three German aces of WWII, Hartmann, 352 kills, Barkhorn, 301 and Rall, 275, who I personally was friends with, had a combined score of 928 kills… Just these three German aviators… And… “It is relatively certain that (at least) 2,500 German fighter pilots attained ace status, having achieved at least 5 aerial victories.”-Wiki The BF 109 was designed in the early ‘30’s and was very advanced for its time, but had some extreme design flaws, and I’m not even talking about it’s terribly low fuel capacity everyone knows about, (demonstrated so graphically in the Battle of Britain,) it’s inability to carry any kind of a significant bomb load, making it a terrible ground-attack aircraft, or with it’s small fuselage that made it a poor photo-recon ship, and hard to keep upgrading, (the G model had so many sheetmetal blisters it was nicknamed “The Bulge,”) and its atrocious low-speed handling under 250kph, (made significantly worse if you added any extra weight: bombs, drop tanks). The most important element of a great fighter aircraft is, of course, a well trained, motivated, hunter in the cockpit, and for much of its combat life it did have that essential ingredient. But for the aircraft, itself, Versatility is *the* key, something the 109 had none of. Single mission speciality was fine for bombers and cargo planes but fighters needed to be ready to perform well at a number of different tasks, chiefly but in no specific order: #1. Ground attack, #2. Photo recon, #3. Air to air, #4. Bomber Escort capabilities. The Bf 109 only excelled in air to air. When flown by an “Experten” who knew her quirks, strengths and weaknesses, she was agile beyond belief, a true little “racehorse.” But as the top Luftwaffe pilots were killed off in their insane “Victory or Death” flying philosophy, without rotating their top pilots back to teach the new ones, that expertise that the original bf 109 pilots had been developing was lost, bit by bit, (to quite quickly in the debacle of the Battle of Britain, where the bf 109’s abysmally poor fuel-carrying capabilities allowing them only a few minutes of fight time at full War Emergency Power, (WEP) an American term, not German, BTW, over the English combat zones, that dumped so many precious and well trained, (some since Spain in ‘36) German pilots in the Channel or British POW camps…which alone won the BoB for England. Or how it was hampered in the Battle of Britain escorting German medium bombers by the foolish combat restrictions, not it’s fault… As a professional military artist in the ‘80’s and ‘90’s I heard all the horror stories connected to this German aircraft from some of the best aviators in history including 109 pilots and Allied testers. (Above: For starters, just about the worst cockpit in aviation history.) The 109 had a horribly small and low cockpit. I once got to sit in a 109 *E*mile at Doug Champlin’s fighter museum in Arizona and it was like crouching in an Altoid box. Its tiny, low space made visibility terrible. That so many German aviators did so well in an aircraft clearly inferior to the FW190, is a bit of a mystery to me... (Above: Early cockpit canopy caged like a greenhouse; Cramped, cold, low, terrible visibility, not a joy to bail from, either. (Above: “109 Canopy 2.0.” Not great, not on a par with the great “bubble” canopies of the later model P-51 D/P-47 D/Corsair or even FW190 D…but an improvement.) One of the most important factors in combat is visibility. The vast majority of pilots never even see the guy who shoots them down. A lot of the game is keeping your eyes peeled, sweeping back and forth for targets, and making sure no one gets the jump on you. A lot of air combat comes down to a few crucial elements: see before being seen, kill before the enemy realizes he is dead, do NOT engage in any turning contests, keep your “energy’”(speed/momentum) up, protect your wingman, and, most importantly, come home alive. Not only was it low, uncomfortable, and at that time of the BoB, poorly heated at best and claustrophobic, it also confirmed what I had heard from another friend, Jeffrey Quill, the Spitfire’s top test pilot from ’38-on, after taking over from “Mutt” Summers, that the tiny cockpit confined the force that pilots could apply on the controls, with obvious effects on the 109’s flight performance. RAF testing in '46 revealed that under some conditions, the force its pilots could exert on the 109’s control column was only 40% of what they could equally apply in a Spitfire. In the time when hydraulically-boosted controls weren’t readily available, this was a major deficiency. The Spit’s two-step rudder pedals also permitted the pilot to lift his feet up during high-G maneuvering, delaying the onset of blackout. Unfortunately for the German pilots the 109 didn’t have those pedals. This was a major issue in the Battle if Britain, and an advantage to the Brits to offshoot the Spitfires’s famous carburettor problem. vs the 109’s superior fuel-injection. (Briefly, when the Spitfire went nose-down to begin a dive, the resulting ,negative G force,manoeuvre would flood the engine's ,carburettor,, causing the engine to stall. The “bubble” canopies of the P-51 and the P-47, for instance, allowed pilots to sit in spacious, high, luxurious, well-heated, comfortable cockpits with maximum visibility as opposed to the Bf 109 where the pilot sat in a cramped, low, chilly, tiny cockpit, with miserable visibility. And it’s incredibly fragile, water-cooled, inverted V 12 Daimler Benz 601/5 engine was the WORST possible engine for combat… (Above: An inverted V 12. Why inverted? A couple of reasons, to have the engine sit lower and improve visibility of the already horrible cockpit; the inverted V made the entire frame a bit more aerodynamic/slippery; for ease of maintenance access, [for example, changing the spark plugs on a 109 was a breeze, as the German ground crewman doesn't have to climb on a ladder, but can just stand on the ground;] less exhaust noise from the lower exhaust stacks; and inverted engines have a little bit less wear because upon start up, the cylinders have a bit better lubrication. This is because gravity causes oil to settle in the cylinder walls. “He who is without oil shall cast out the first rod...”-Detonations 5:72. But while its Daimler-Benz DB601/5 engines inverted V-12s were masterpieces of design and manufacture, they were the *worst* type of engine for actual combat. Like the Allison or Rolls Royce Merlins they were water-cooled and incredibly fragile; Just like your home car: if there was the tiniest leak/hit on any of its vulnerable radiators, (unfortunately exposed in it’s lower wing surfaces, although not quite as bad as the P-51’s huge belly scoop,) water jackets, pumps and hoses, it quickly expelled the coolant, the close tolerances would get *real* close and with a disconcerting CLANG the engine would seize up, turning your beautiful, graceful 109, P-51 or P-40 into a brick. (Give me a Pratt & Whitney R2800 or BMW 801 air-cooled, radial engine that can literally have two complete cylinders shot away and *still* get me home.) (Above: Daimler Benz DB 605- incredibly gorgeous, technically advanced…fragile as tissue paper. One tiny splinter of steel the size of a fingernail clipping, “golden BB”, anywhere in the water-cooling system and it’s ..,Farewell and adieu to you,, ,Spanish Ladies,…”) But worst of all…and hang on to your hats, if you haven't heard about this…approximately 33,984 Bf 109s were built in total, more than any other fighter in WWII, in continuous manufacture from 1936–1945… …and possibly 33%, almost 11,000, crashed on mostly landings and takeoffs, but some taxiing, due to its insanely narrow landing gear geometry, with its gear and motors placed, not widely on its wings, but in its belly. (The Spitfire has a similar placement but a bit more forgiving geometry.) Most were not “totalled,” of course, being repaired to fly (and crash) again, but it killed or wounded thousand of precious young German pilots, lost not in combat, but often in training or landing accidents. The main repair issue was not just the gear but the engine damage when the prop “face-planted,” locked on the revving engine and ripped it’s internals apart. (For perspective: A Bf 109 approaches at 120 mph, and lands at about 105–110 mph. Ever been in a car crash at 110 mph? The harness safety system/padded dash/”airbags” of a 1941 Bf 109 were not quite as good as your family car in 2021, esp. if it flips. Thousands of pilots died or were injured.) Some say this is a myth, but consider this: when some of the top German aces of all time, actual Messerschmidt factory designers and THE top two Allied test pilots of all time all say the same thing, it’s worth a bit more than a consideration, in my opinion. Both “Corky” Meyer and Capt Eric Brown published the story and as far as I know, nobody’s refuted it officially. “When the old dog growls, its best to look out the window.”-Old Norwegian proverb. “Corky” Meyer, Grumman’s top test pilot, who brought in the Hell/Bear/Tigercats and many of their jets, published in 2003 in his “Flight Journal”: “...11,000 of the 33,000 (109s) built were destroyed during takeoff and landing accidents...Chief aerodynamicist for the the Messerschmitt Me 163 rocket fighter, (itself not exactly a paragon of safety and wisdom,) Josef Hubert (advising/working for Grumman after the war on their new jets)....told me that Willy Messerschmitt had adamantly refused to compromise the Bf 109’s performance by adding the drag-producing wing-surface bumps and fairings that would have been necessary to accommodate the wheels with the proper geometry. This would have reduced its accident rate to within expected military-fighter ranges and made it a world standard!” -2003 August, Flight Journal, “The Best WWII Fighter” by “Corky” Meyer. (Above: In addition to its horrible gear geometry, the gear itself was built quite spindly and thin and apparently out of the same “Waterford crystal” the Tiger and Panther tank’s final drive gears were manufactured from ;-) And…Meyer sites a letter in 1980 written by Colonel Johannes “Macki” Steinhoff, 176 victories, #23 ace of all time, who mostly flew the 109 and then 262s and like Rall, was actually one of the very few who flew/survived the entire war, 1939–45, but terribly wounded, and with his face severely burned.: “He sent me a long letter relating that I should be sure of the absolute vertical alignment of the tailwheel; he also wrote that its inherently weak brakes should be in excellent condition because in WWII, the Luftwaffe lost 11,000 out of 33,000 Bf 109s to takeoff and landing accidents. Steinhoff directly attributed this terrible record to the bad geometry of the plane’s very unstable, splayed-out, narrow landing-gear configuration. In his letter, he said twice that if a German mechanic who really knew the Bf 109 wasn’t handy, I should *not* get into the cockpit.”-2000 Winter, Flight Journal Special Edition WWII Fighters, “The Bf 109′s Real Enemy Was Itself.”- by “Corky” Meyer. (Above: Insane mathematics needlessly cost the lives and health of thousands of young German pilots.) Bf 109s always had a tendency to pull left, and the pilots, esp green ones, always had to be attentive for a burst of wind, bumps in the field, and esp. a surge of torque from the engine, (esp. the later more powerful 605s DB/DC engines with mods,) etc. and you better effin’ keep your foot right over the left pedal, covered and ready. Landings were much more difficult, esp. with fatigue, wounds, low fuel, etc. I talked with Mr. Rall, who adored his 109, about the narrow gear. He hesitated then: “…Very problematic, especially for young pilots without the necessary muscle-memory training.” This issue was also brought up once at Oshkosh when he gave one of the big tent talks. (Above: ,Günther Rall. “,During World War II Rall was credited with the destruction of 275 enemy aircraft in 621 combat missions. He was shot down five times and wounded on three occasions. Rall claimed all of his victories in a ,Messerschmitt Bf 109,.” -Wiki.) (Above: Check out the insanely narrow gear. The Spitfire had a similar design but much more forgiving “mathematics.” Compare it to below, the magnificent Fw190’s wide-stance gear.) And then, from Eric Brown, THE top test pilot of all time who test flew a number of different 109 Marks… “,Captain, Eric Melrose "Winkle" Brown, ,CBE,, ,DSC,, ,AFC,, ,Hon FRAeS,, ,RN,[1], (21 January 1919 – 21 February 2016) was a Scottish ,Royal Navy,officer and ,test pilot, who flew 487 types of aircraft, more than anyone else in history.”-Wiki “But the Bf 109’s deficiencies almost equal its fabulous assets. The Luftwaffe lost 11,000 of these thoroughbred fighting machines in takeoff and landing accidents, most of them at the end of the War when they needed them most…I felt certain, too, that the landing gear’s being slightly splayed outward aggravated the ground-looping tendency and contributed to the excessive tire wear and bursts. The Spitfire had a similar, narrow-track landing gear, but it was not splayed out like that of the Bf 109, and the Spitfire didn’t show any ground-looping propensities.” Brown went on to explain that high accident rates in 1939 resulted in a tailwheel lock being added to later models.-1999 December, Flight Journal, “Combat Warrior, The Historical View” by Captain Eric Brown, likely the best test pilot in history. (Above: Experienced pilots were always prepared for the Bf 109’s skittishness esp. on landings, but thousands of young , inexperienced pilots were injured or killed because of Willy Messerschmidt’s ego in retaining his (admitted) beautiful 109 wing.) The 109 was a busy little “sports car,” a “race horse” that took expertise to fly it to its max, something many Luftwaffe pilots could do initially, flying all the way back to Spain learning all it’s little intricacies and tricks that made it so agile and deadly, but in their defeat at the Battle of Britain those wonderful ‘experten,’ ended up in the Channel or in English POW camps. Later models automated more functions, but it was still hard to fly well without vast expertise and practice, something the sometimes only 50-hour-trained German boys would never get, who became fodder for the experienced Allied aviators. Early models had a hard time keeping engine temp at the optimum, and early 109 pilots had to have been busier than one-armed paper hangers flying, fighting, adjusting radiator doors, etc. This was a complicated aircraft that reality needed to be *flown!* and the terrible toll of experienced pilots just got worse and worse as the war progressed. Another reason Germany should have phased it out and focused/built the much better, much easier to fly FW 190 series. One of the problems with the 109s was the constant upgrades necessary to try and keep this old aircraft even a bit competitive to the Allied fighters. Every aircraft was precious and had to be kept flying. There were often so many different “M”odels, modifications, upgrades, etc, on a single field the ground crews couldn’t keep up with the staggering array of parts, factory bulletins, improvements, new parts, new maintenance routines, let alone the constant regular day-to-day maintenance to simply keep their crates in the air, let alone keep up with the factory upgrades. And the quality of the field maintenance suffered, not even counting the entire engines that had to be sent back to the factory for the most intricate work, and not even counting the continued deterioration of the German railroad system, likely German’s greatest weapon in WWII, that was being systematically destroyed, and unable to keep up with the constant stream of parts necessary to keep them all flying, competitively or not. Not insignificantly, the quality of the German synthetic fuel and lubricants kept dropping in the successful Allied bombing efforts against it, not the Bf 109’s fault, but the significantly tighter tolerances of the water-cooled DB engines was majorly effected, but quite not so much as the looser mechanical tolerances of the far superior BMW 801 air-cooled engines. The BF 109 was an outstanding aircraft but starting with the battles against the Spitfires, and as the war progressed, it suffered one great, almost insurmountable, weakness compared to the British and American aircraft it battled against: it was significantly slower. The DB 601, esp., was just never able to run at the higher horsepower levels that the Allies could. And there are many reasons for this: from supercharger gearing to intake manifold pressures to octane ratings to levels of tuning and too many more to get into on this broad answer. Most of its combat advantages and subtleties that made it, as I said, agile and deadly, were lost to the new batch of poorly trained pilots that were being fielded and from the drastic change in combat tactics, from the twisting, tight-turning dogfights over The Channel to the “zoom and boom,” ambush-dive, roll, ”energy” tactics of the later war that did not favour the poorly diving/rolling 109. Mr. Rall used these tactics well as he was an expert, but the younger, greener German pilots, were not taught these subtleties, tricks and tactics and from mid 1944 on, the Bf 109’s in any configuration or variant, increasingly became fast moving “fawns” to the Spitfires, P-51s and P-47 “wolves.” The final “K” 109 models were, as a testament to some brilliant German engineering, for a change, much faster, but still came too late in the game and again were in the hands of third-rate pilots/boys. A major part of this speed deficiency, besides the Allied advantages in fuel octane allowing significant higher manifold pressures, was it’s supercharger: a brilliant 2-stage supercharger (perhaps the greatest advantage over the significantly better Fw 190 giving better performance at higher altitude until the FW 190D models,) which, as good as it was, couldn’t compete with the P-47’s huge turbo-supercharged R2800 and the P-51’s DUAL superchargers. The 109’s DB 605 engine was significantly bigger in displacement (32%) than the Rolls Royce Packard-built Merlin, but the P-51s had two superchargers attached: one feeding the engine and one feeding the other supercharger. And there were two main version of the Merlin 1650: the -7 version was geared so its supercharger drive speed would be optimal at War Emergency Power (WEP) with 130 octane fuel at 6200 feet with the supercharger in low speed and at 19,300 feet in high speed. (The -7 is the Merlin typically quoted for HP numbers.) This version was not optimal for escorting high altitude bombers at 25,000 feet so another Merlin version, the -3 which had different supercharger drive ratios which changed the shaft speed, was introduced. The -3 engine actually has less power overall but gives it more power at 17,000 feet and 28,800 feet at high speed. And as the 109 G’s start running out of steam at 18,800 feet that’s a huge advantage for the P-51. The -3 has 1720 HP on 120 octane fuel vs 1595 for the -7 but its a question of where that power is *available.* Laymen sometimes just look at raw data, who’s got the most, biggest, fastest, etc. but don't understand the practical application of the numbers and their often subtle nuances in real life performance. When I was drag racing motorcycles, for instance, you don't just look at sheer horsepower, but the transmission/clutch, quality of the tires and skill of the rider, not to mention the quality and make-up of the road surface you’re racing on. Too much horsepower and sometimes you can’t “get it to the road”, and you waste it spinning your tires, “going nowhere fast.” Many P-51’s were retrofitted with the -3 supercharger kits giving less overall HP but more where they needed it at high altitudes. Another big issue was that the P-51′s Merlin had an after-cooler, a liquid-to-air heat exchanger that cooled the hot air coming out of the superchargers, similar to modern liquid-to-air intercoolers found on high performance cars today. The after-cooler adds power in two ways: first it increases the density of the charge by cooling it, and second, it reduces the tendency to knock allowing greater manifold pressure. So the 109 did NOT have dual stage superchargers, the first feeding the engine and the second feeding the first supercharger. And it did NOT have an after-cooler. (Here’s where Willy Messerschmidt additionally screwed up on the initial design: by designing it as such a little “racehorse,” the actual physical size of the 109 was so small, the fuselage was so tight, it had very little room for the modifications it needed to stay competitive from 1936 -1945. Folks not in the know deride the huge P-47 for its huge size not understanding the incredible advantages of the bigger fighter beyond the fact that enemy projectiles had to travel through significant amounts of steel to hit anything vital, and the room to continue to upgrade it as the war and technology progresses. (Above: A huge reason the P-47 had the best survival rate of any aircraft in WWII: the exceptionally low rate of 0.7 per cent per mission, THE most important factor of air combat, bringing your pilot home, one of the reasons the P-47 was THE greatest fighter aircraft in ETO and likely the entire war. Plus its size and strength as THE best manufactured aircraft of WWII, significantly more expensive than the P-51, for example. You get what you pay for.) Add to that the Allies 130 octane fuel vs the German’s 95 and there is a huge advantage in speed of 40–60 mph. It is also a testament at this time to German engineering that the DB 605 was even as close to the Merlin as it was, but also remembering it did have 32% more displacement. And then near mid-1944, the Allies fuel octane jumped up to and became standard at 150, another significant advantage. Was this significant? A P-51 that had run at 67 inches manifold pressure at WEP on 130 octane could now run at 75 inches on 150 octane. (A note on War Emergency Power: its a throttle setting. At full throttle the P-51, for instance is running at 61 inches of manifold pressure, but if the pilot needs an extra burst of power… …he pushes the throttle forward HARD, it will break a “stop wire” and go farther forward and deliver either 67 or 75 inches of manifold pressure depending on which setup/fuel which gave the pilot 5 minutes at WEP. After debriefing each pilot had to log the minutes under WEP and after 50 hours of WEP the engine was removed, and disassembled looking for signs of extra wear. (The P-47′s incredibly tough, and lower tolerance air-cooled R2800 engines could run much longer and harder on WEP and with significantly less wear.) Also WEP did nothing for Allied fighters below 5000 feet. At higher altitude, however the increase in HP was between 100–150 HP. Additionally the P-51’s Merlin also could rev higher that the 109s DB 605: 3000 rpm vs 2700 rpm. There trick for fighting a P-51/P-47 was to fight it at less than 20,000 feet, and the German pilots were taught to bring the fight down to lower levels if possible where it was more agile…but the P-51 and esp the P-47 were far better divers, and the P-47 was also a significantly better roller, so that was tricky, also as the German pilots were steadily getting greener and the U.S. pilots were getting better. The Germans were also in a terrible disadvantage in the quality of their fuel, much of it synthetic. Allied aircraftT used 100/130 octane avgas vs their 87 octane. A must-read is about Eugene Houdry and Alex Golden Oblad, two unsung heroes of the battle of Britain and WWII itself, and their work on a chemical catalyst process for the Sun Oil Company, now Sunoco, which converted almost useless crude oil/sludge into 100-octane fuel that America gave England to replace the standard European 87 octane fuel just before the Battle of Britain and helped increased the Spitfire's speed by 25 mph at sea level by 34 mph at 10,000 feet, a not inconsiderable advantage against the 109s. Connected to my paragraph above about the significant speed deficiency of the 109 to esp. P-47s and P-51s, the Germans being more and more on the defensive as the war progressed, for example, as the German ground crew’s ability to specifically fine-tune and optimise the 109’s manifold pressures to a specific altitude for maximum power was lost to the “REactive/defensive” position vs the allied “ACTion”/offensive moves, where the British and American ground crews were able to fine-tune their Spitfires, P-51s and P-47s for maximum power knowing at approximately what altitude their pilots would be flying their missions at. The 100/130 av-gas allowed the U.S. planes to run “hotter” manifold pressures, and have considerable power/speed advantages. This one-down position of the Luftwaffe, esp. the 109s, was another distinct disadvantage. The Germans kept trying to replace the 109 but without success; the hoped -for replacement 209s/309s were expensive failures, additionally hurt by Hitler’s personal affection/blindness for Willy Messerschmidt, himself. Why they didn't gear their entire production capabilities towards the far superior, newer and more upgradable Fw190 series that was NOT at the end of its development cycle, then the tired-out 109 is testimony more to Willy Messerschmidt’s good status with Hitler than the aircraft’s basic abilities, now stale, and their poor long-range strategic manufacturing planning, also reflected in the incredibly poor but horribly expensive “performance” of the Tiger (and then to a bit lesser extent with the Panther tank) series and how they were insanely committed to it for years with vast amounts of wasted resources, (i.e. massive “Sunk Cost Mentality”: “Hey, We’ve already put this much wasted effort and a zillion Reichsmarks into these sweaty turkeys, we can’t quit now!”) again connected to Hitler’s hard-on for “super-weapons”, gigantic artillery pieces, ridiculous Maus AFVs, resource stealing V-Weapons, and a never-ending array of amazing but unbuildable aircraft, stunning designs beyond their time, but impractical in the very limited time/resources/alloys/fuel that a losing Germany was facing. Endless expensive mechanical manifestations of the “Get-Rich-Quick Scheme/Miracle War-Winning Zuper-Veapons!” As Dr. Phil would have said, “How’s that workin’ for you?” The only way the Germans could increase the G models to compete with the allies they *had* to increase the manifold pressures and created the MW (methanol-water) 50 system which is a methanol-water injection system, using a 22.5 gallon tank (85 liter) behind the cockpit and running a line to to the engine, ridiculously simple, and with it the G14 model could run 51 inches of manifold pressure making 1775 Hp, up 300 hp of the older G6 Models, running 42.5 inches of manifold pressure, giving the G14 a top speed of 413 mph, (and a high altitude version the G14 As, which had it’s supercharger optimised for fighting up high, with a top speed of 422 mph.) It could be used for 30 minutes total, only ten minutes at a time, with a 3 minute cool-down period between each. Again not as fast as the P-51Ds or P-47Ds but at least the Mustangs and Thunderbolts could not so easily escape the fight at will against the slower G4s. That the K model was so fast was a true burst of engineering brilliance from the German designers/engineers, esp with the MW 50 methanol-water injection that was incredibly simple, but wasted on the green pilots. Maybe 500 K’s were made, about half were destroyed before they even flew, and the K4 was the best of them all, 2000 hp, 452 mph, the only one that was a bit faster than a P-51D, (425 - 447 mph) but in the hands of a rare surviving “experten,” was very dangerous. But it was, of course, pretty hopeless for the Germans by that time. Part of the increased speed was the very limited amounts of the new and in limited-amounts, German C3 fuel with 100 octane rating (vs their usual B4 synthetic fuel with 87 octane, which, BTW, with the MW system on the G14s, raise the octane of the 87 fuel to 100, just by itself from the anti-knock function of the water.) But here's the thing, the Germans *had* the technology for the MW 50 system back in 1940, but never utilised it! Imagine if they had used it on the old E models in the Battle of Britain in 1940 (and the Fw 190s set up in 1941), increasing the 109’s HP by an extra 200–300, it could have made things potentially very tough for the British…until you remember the never-ending problem of the Bf 109’s low fuel capacity and its inability to carry much external weight. So if the Bf 109, magnificent in the ‘30’s, ran out of steam in the ‘40’s, how could it have shot down more enemy aircraft than any other design? Because it was made in greater numbers than any other fighter of WWII and its pilots were initially simply the best of the war, true “experten,”(except for some of the early Japanese aviators that were almost acrobatic.) Even when it couldn’t compete head to head with the Spitfires, P-51s and P-47s there were still some amazing old German aviators flying that scored massive numbers with this most agile “racehorse”, mostly in the East, flying off grass fields close to the front lines, flying huge numbers of missions, racking up huge scores. But as the best ones were killed, the young pilots couldn’t make use of it’s intricacies and quirks and the Bf 109s started killing and injuring so many of its own young, green pilots in landing/take-off accidents due to the terrible gear geometry, (and esp. with the more powerful later Models like the “K” that were famous for torque surges on landing,) and at the hands of the cadre of great new Allied pilots. It worked hard to defeat itself. Thanks for reading my rant. Big thanks to ‘Greg’s Airplanes and Automobiles’ on Youtube.

What was the advantage of the P-38 and it's unique twin fuselage design?

The P-38 was created in response to a proposal for a long range, high altitude interceptor of bombers. It needed to be big to get the range and to be heavily armed. To be big it needed 2 engines and the decision by the Army Air Corps was made to use the one liquid cooled V-12 in American production , ,Allison V-1710 - Wikipedia,. The Air Corps was especially interested in using turbocharging, feeling it was the future of high altitude aviation, which it was but not in 1936. There were many problems with the Allison because of the turbos. The high temperature materials available of the time were grossly inadequate in comparison to what goes in a turbo now, the controls were primitive and the aerodynamics of all that air rushing through ducting and over the tubing blades was not well understood. By the end of the war progress was made in taming the turbo both in the P-38 and the later P-49 and B-29 which were the ultimate high altitude machines of WWII with their big radials but in the beginning the promise was probably illusory. Multistage super chargers were the key to the successful Merlin series power plants and the German engines. (The Russians mainly fought below 20,000 feet and wasted no effort on complicated turbo superchargers.) The turbo supercharger determined the twin boom layout. To duct the turbo required space. Curtis and Bell, makers of the P-40 and P-39 gave up on on the GE turbo. It just did not fit in a fuselage along with a pilot and fuel. Lockheed gave each engine a fuselage of its own without the encumbrance of a pilot so the turbo and its intercooler along with the radiator could be positioned. Republic created the P-47 in one fuselage by making an almost double sized plane at 10,000 lbs. v 7,500 lbs. for a P-51. Unfortunately bigger planes do not maneuver as quickly as smaller planes, and in practice the P-38 was less agile than the Me-109. It was not designed as a dog fighter and when used in that fashion did not do especially well. But it was never in use as a high altitude long rang interceptor because the US never had the need. And there were serious aerodynamic problems as the plane was the first to reach high subsonic speeds and discover ,Mach tuck - Wikipedia,. There is really a laundry list of problems with the P-38, just like virtually very cutting edge plane. They became unwanted in the ETO. What did they do right? They kept at it and fixed the problems. Mach tuck, with its disastrous tendencies to become a lawn dart was overcome. The added dive flaps and added hydraulic assisted controls created a plane that could roll better than anything in the Pacific. The controls were at least partially tamed so that one pilot could manage 2 engines. And the fuel consumption in cruise was dramatically cut. In the end there was a long range, heavily armed, excellent gun platform that could out run and out dive any opponent. In the beginning its 2 engines were so unreliable that they just meant it was twice as likely to fail. In the end they they became an asset bringing home pilots that would have had little chance of rescue with single engine mechanical or combat damage failure.

Is it true that P-51 Mustang was designed with heavy input from RAF engineers?

The Mustang was designed in 1940 by North American (NAA) in response to a requirement of the British Purchasing Commission. The Purchasing Commission approached North American Aviation to build Curtis P40 under license for the RAF. Rather than build an old design from another company, North American Aviation proposed the design and production of a more modern fighter, but powered with a non turbo charged Allison engine to save time When the first Mustangs arrived in England, Royal Air Force test pilots quickly discovered that although the new fighter was very agile and fast its performance began to degrade at altitudes above 15,000 feet as the normally aspirated Allison engines lost power. This was of no use to the RAF in taking on German fighters, but it would still be a good support and reconnaisance plane. In April 1942, Rolls-Royce test pilot Ronald Harker visited the RAF Air Fighting Development Unit field at Duxford, and was invited to try out a Mustang. He flew the aircraft for a half-hour and was extremely impressed with it, until he ran into its poor high-altitude performance. He realized that a two-stage Merlin engine (the Merlin 61) was exactly what was needed, and consulted with the Rolls-Royce chief engineer to see what the British engine would do for the American fighter. Studies for a Mustang with a Merlin engine suggested a top speed of 710 KPH (440 MPH) at an altitude of 7.8 kilometers (26,000 feet), well in excess of the capabilities of an Allison Mustang, and possibly even superior to the Spitfire IX in some respects. Harker pressed his case through the air establishment, and within days Rolls-Royce's facility at Hucknall began conversion of three Mustangs to two-stage Merlin power, with two more conversions put in the queue later. These aircraft were fitted with the Merlin 65 engine subvariant and a four-bladed propeller. The Merlin 65 was optimized for better performance at lower altitude, though unlike the Allison its performance did not drastically fall off at high altitude. Back in California, while these events were taking place in England, NAA engineers were working along a similar path. They had known about the two-stage Merlin engine since late 1941, and had been considering how to use it with the Mustang. Packard had negotiated with Rolls-Royce to build a licensed version of a two-stage Merlins, and was moving into production of the Packard V-1650-3, equivalent to the Merlin 68 sub-variant. The first V-1650-3 engines were to roll off Packard production lines in mid-December 1942, with production ramping up to full volume in the following months. If NAA engineers wanted to use Merlin power, the engines would be available when they were needed. NAA didn't start work on the concept in earnest until late July 1942, when the company received the two cannon-armed NA-91s reserved for experimental purposes by the USAAF, mentioned earlier, and Merlin 65 engines sent from England. This step-up in activity appears to have been partly the work of Lieutenant Colonel Tommy Hitchcock, the US Assistant Military Attache at the American embassy in London. He had flown the Mustang, knew about the Rolls-Royce effort at Hucknall, and was enthusiastically promoting the idea through American channels. NAA engineers threw themselves into the project with the same energy that they had shown in rolling out the initial NA-73X. The new variant was given the company designation of "NA-101" and military designation of "XP-78". By the summer of 1942, work on the Merlin Mustang was in full swing on both sides of the Atlantic. The two groups were aware of each other's activities, and the spirit was competitive but friendly. The Rolls-Royce group had a head start and got into the air first with their "Mustang X", as the conversions were known, with the initial aircraft flying on 13 October 1942. The next day, Packard officials sent a letter to Rolls-Royce congratulating them on "beaten us to it on the flight of the [Merlin] Mustang. Hope performance is up to expectations." The Rolls-Royce conversions were experimental improvisations. The conversions featured a deep chin scoop underneath the prop spinner that was faintly reminiscent of late-model P-40s, and gave them a unique appearance among the Mustang family. The first Mustang X was originally fitted with a standard Rotol (Rolls-Bristol) four-bladed propeller, as used by the Spitfire IX. The performance was nonetheless very satisfactory. The Merlin 65 could provide more horsepower at altitude than the Allison V-1710 did at takeoff, and the initial Mustang X conversion achieved 700 KPH (433 MPH) at an altitude of 6.7 kilometers (22,000 feet). The aircraft could reach an altitude of 6.1 kilometers (20,000 feet) in 6.3 minutes, about two-thirds the time required by an Allison Mustang. Greater power and torque resulted in a degree of lateral instability in the Mustang X. Various fixes for this problem were considered during the evaluation, including a bigger tailfin, but the problem would get worse before it got better. The second Mustang X flew on 13 November 1942, and the third flew a month later. Rolls-Royce kept NAA informed of the results of the tests while NAA refined their own conversion, which had been redesignated "XP-51B" in the meantime. The first XP-51B flew on 30 November 1942. As with the Mustang X, performance of the XP-51B demonstrated that faith in the Merlin conversion was justified. NAA test pilot Bob Chilton achieved a level speed of 710 KPH (441 MPH) at an altitude of 9 kilometers (29,800 feet), and the XP-51B could climb almost twice as fast as an Allison Mustang. This first XP-51B was roughly an "80% conversion", but the second, which flew soon afterward, was close to a production design. The Merlin 65 had a similar physical "envelope" to the Allison V-1710, but weighed about 136 kilograms (300 pounds) more, and required fitting the intercooler someplace in the fuselage. The Merlin Xs had the intercooler under the nose, but that arrangement was cluttered, and after a six-week bout of headaches NAA engineers managed to accommodate it in the radiator system under the cockpit. They also managed to obtain a small amount of thrust out of the radiator exhaust. In any case, the modification resulted in the belly airscoop hanging a bit lower than in the Allison Mustang. This was a slight visible change, as was the slightly fatter nose; more noticeable was the switch of the carburetor intake from above to below the prop spinner, giving the new Mustang version sleeker looks than its predecessor. The new design also featured a four-bladed Hamilton Standard propeller with a span of 3.4 meters (11 feet 2 inches), replacing the 3-bladed propeller used on the Allison Mustangs. The American Merlins were built under licence by Packard-Bell. This aircraft became the P-51B flown by both the USAAF and RAF (The P-51C was the same aircraft but built at Fort Worth). One long-standing annoyance was the canopy scheme, which gave a poor view to the rear; prevented the pilot from getting a clear view ahead over the long nose in takeoff; could not be opened in normal flight; and was difficult to get out of in an emergency. The RAF came up with their own solution by replacing the three NAA canopy panels with a one-piece bubble "hood", similar to that used on the Spitfire, that slid back to the rear. The new canopy design was implemented by the British firm of R. Malcolm Limited, and consisted of one-piece blown Perspex bubble that could be easily refitted to the Mustang by field maintenance personnel. The "Malcolm hood" was refitted to most RAF Mustang IIIs, and was apparently fitted to some USAAF P-51Bs and even some of the old Allison Mustangs. Although the RAF remedied the poor rear view of the razorback Mustang with the excellent Malcolm hood, NAA decided on a different approach, though it was derived from British work as well. Colonel Mark Bradley had visited England in early 1943, and had seen the "bubble" canopies that the British had developed for the Spitfire and Typhoon. The bubble canopies gave a pilot unobstructed all-round vision. Bradley returned to the US and pushed to get bubble canopies fitted onto American fighters. Republic quickly put one on a P-47, and Bradley flew the modified Thunderbolt to California to show it to NAA's Dutch Kindelberger. NAA very quickly came up with a plan to cut back the rear fuselage of the Mustang and mount a large bubble canopy over the cockpit. The canopy would slide open back over the rear fuselage. Two P-51Bs were pulled from the assembly line as proof-of-concept demonstrators, and the first bubble-top "XP-51D" (company designation "NA-106") took to the air on 17 November 1943. Another problem was that, even with drop tanks, the Mustang still didn't have enough range to escort Eighth AF bombers all the way to Berlin and back. The USAAF had been testing a potential long-range fighter, the Fisher XP-75, that had proven unsatisfactory, and needed something immediately that could do the job. USAAF Colonel Mark Bradley, who had been in charge of testing the XP-75, told NAA's Dutch Kindelberger that there was some empty space in the rear fuselage of the Mustang, and that another fuel tank should to be put there. NAA engineers devised a 322-liter (85 US gallon) tank that fit between the pilot's seat and the radio. The new tank gave the Mustang the necessary range, solving one problem, if at the expense of creating another. The new fuel tank was added without concern for its effect on the Mustang's center of gravity. With a full fuel load, getting the fighter off the runway was downright dangerous, and the aircraft was only marginally controllable for the first hour or so that it took to drain the tank. That had to do, there was a war on and something was needed right away, so the third tank was fitted to late-production P-51Bs. The British also made their own contribution to the range problem in the form of a new drop tank that accommodated 409 liters (108 US gallons) and which was made of plastic-impregnated paper. That sounds a little crazy, particularly since the fuel would rot the tank if left in it for more than eight hours. However, the paper drop tanks were perfectly effective, and were lighter and cheaper than metal drop tanks. Dropping them over German territory also did not provide the enemy with aluminum they could scavenge for their own war effort. Production rates of the paper drop tanks eventually reached 24,000 a month. A 416-liter (110 US gallon) drop tank was also built, plus a 568-liter (150 US gallon) ferry tank. Information on these tanks is sketchy, but the ferry tank looked like a tub whose upper rim fit up against the wing, and so it appears it could not be dropped in flight. Another improvement did much to increase the P-51D's lethality. Once again British engineering made a considerable contribution to the Mustang, this time in the form of the British Ferranti "GGS Mark IID" computing gyro sight, replacing the relatively simple Bell & Howell gunsights used to this time. The Ferranti sight, manufactured under license in the US as the "K-14", allowed the pilot to dial in the target wingspan and target range, and then told the pilot when he had a good shot at the target. The K-14 was regarded as a marvel of technology and greatly increased the pilot's accuracy in deflection shots. Later P-51D production would also feature AN/APS-13 tail warning radar, with rod antennas sprouting from the tailfin, to give warning of attack from the rear. Other changes included a wing with slightly greater chord at the root, plus stronger main gear to handle the aircraft's increased weight. One significant change was the addition of a dorsal fin fillet to the tailfin, added after initial P-51D production. The fillet compensated for yaw instability problems that had become increasingly troublesome with the introduction of the Merlin engine, the addition of the fuselage fuel tank, and the cut-back of the rear fuselage. These changes, and an increase from 4 to 6 .50cal guns became the P-51D. So as you can see from this, the Mustang - a British purchasing name - came about from a British requirement and a unique American design. As we were the customer - the USAAF were not interested in it in the beginning - we did all of the major testing, both experimentally and in combat, and fed that information back to NAA. We also had the best aircraft engines around, and wanted the best performance, plus we weren’t worried about sharing new technology (please remind the Pentagon about this today), and our test pilots were convinced that the Mustang could really excel - and what a plane it turned out to be.

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