|
wdolson -> RE: Name this plane? (4/30/2014 11:29:10 AM)
|
quote:
ORIGINAL: Erkki
This is going waaaay OT already but WW2 aviation discussions are never bad are they? [8D]
As long as nobody is getting too worked up and deciding this thread is the anthill they are going to die on, these discussions are usually interesting to me.
quote:
Actually during the second half of the war about half of the German aviation fuel was 96 octane c3 fuel which I believe was at least partly synthetical(from coal). There were some aircraft that used c3 fuel only(such as many late 109s) and some that could do with the older b4. The c3 ones could naturally achieve higher boost ratings without knocking where older ones needed anti-knocking boost systems such as MW50 water-methanol injection.
I thought C3 was 96, but it appears that I misremembered (just looked it up). It appears that some DB605s were built to use C3, but the shortage of high octane fuel caused them to downgrade back to B4. Of course everyone was using some kind of injection for fighters by the end of the war.
The Fw-190 was never as well liked by the powers that be within the government, partially because Kurt Tank was not as buddy buddy with them as Willie Messerschmidt was, but also because of the engines. The Fw-190A/F/G used the BMW-801 which absolutely needed C3 fuel and there was no way around it. By 1944 fuel production was stressed to the max. I think one reason the Me-109 stayed in production despite the short range, unstable landing gear, and a bit of obsolescence was because it was a decent fighter that could use the 87 octane fuel.
quote:
I had hard time finding a good photograph but the Luftwaffe aircraft actually had used the fuel type marked in the plane near the refueling port, the model plane of the link has "c3" written in a orange-yellow triange behind the cockpit: http://www.hyperscale.com/features/2001/images/K4_300.JPG
I've built models my whole life. I know what you're talking about. Though others here may not have ever noticed it.
quote:
DB engine series was very different from the Merlin. It had numerous smaller and bigger advantages such as ability to maintain full power even in high negative G force or inverted flight for a long time(until the oil temp. would raise too much) given by the fuel injection. Merlin could do that only with late-war pressurized carburettor and even then for only a moment. DB601/605 series provided a very high max output power for a small and lightweight engine unit, and the whole engine-supercharger-gearing-propeller system was more automated than the Merlin's(no separate mixture, prop pitch or supercharger stage control needed from the pilot after Bf 109 E-7). The inverted-V was used for ease-of-maintenance, center of gravity and cockpit visibility reasons + for the ease of installing a weapon firing through the propeller hub, recoil being along the center-of-mass of the aircraft.
However the downsides of the engine design included(relatively) high fuel consumption at cruise speed, which is one of the reasons behind Bf 109's short range and low-ish endurance time relative to fuel carried compared to the Spitfire, other Merlin-engined aircraft or even Fw 190. Also when the same engine type got overengineered new issues arose, and some 109 models(specifically G-1 to G-6 + G-12 and G-14, AFAIK, the ones that used DB605A) suffered from the engine crankshaft breaks mid-flight. None of the WW2 aero-engines were exactly reliable by modern standards but for the Germans this was especially grim. Its possible that up to a full percent of the whole production was lost to mid-flight engine fires. The most famous victim this malfunction is the 158-victory Bf 109 ace Hans-Joachim Marseille.
The Spitfire had pretty short range and the Mustang had fuel tanks crammed in everywhere, but it is notable the range the USAAF got out of the Mustang. That was what made its reputation. It was a better dogfighter than the P-47, but the P-47s still ran up a pretty hefty score against a better trained Luftwaffe than the Mustang faced for most of its career. As Allied fighters increased their range, the Luftwaffe just kept pulling back their defenses until the bulk of their fighters were over Germany itself and out of the max range of the P-47, even with drop tanks on every hard point. The Mustang was the first good performance fighter that could get into Germany and duel with the Luftwaffe.
I saw a modern analysis of the Mustang's aerodynamics and it had an advantage that wasn't realized until recently. It's been thought the extremely good fuel efficiency was a combination of the engine (which was more fuel efficient than other high performance engines) and the laminar flow wing, but it was actually the radiator design that made the difference. The way the radiator was designed, it actually produced a bit of thrust, so the plane had a low thrust jet engine from something that was a net drag on other liquid cooled planes.
A number of other planes tried laminar flow wings to try and replicate the P-51's success (such as the P-40Q and P-63, but failed to achieve the performance.
The P-38 had the range, but it had temperamental superchargers. The superchargers were fine in hot weather and they were fine in cold, dry weather, but the oil in them tended to jellify in cold, damp climates, which was pretty common in Europe. The P-38 had a reputation as a dog in Northern Europe because it had a tendency to have the turbos kick out when the pilot really needed them. Lockheed fixed the problem by the P-38J, but it was mostly only being used for recon and pathfinder roles in Northern Europe at that point.
Bill
|
|
|
|
