Race for 650 km/h (~400 mph) fighter

[tomo pauk]

Who has the best odds to came out with a 400 mph fighter as early as possible, that still has meaningful armament, range (not same requirements for European , protection and general usability - ie. not being a glorified race aircraft? By meaningful armament, I mean either 8 LMGs, or 4 HMGs, or 2 cannons, or a mix that was often found on different historical fighters. Who will be playing catch-up between the 'big' countries?
Obviously the good engine(s) are needed, as well as good engines' installations, along with aerodynamics not lagging behind what other people were doing.
Preferably 1-engined A/C.

 

[thunderbird]

You phrase the question as "who will...", when a review of history can answer this as "who did...". The American trio of P-38, P-47 and F4U were the first 400 mph fighters with good armament.

 

[SaparotRob]

They were even faster when the balkenkreuz was applied.

 

[tomo pauk]

You phrase the question as "who will...", when a review of history can answer this as "who did...".

My English language is not the best, so perhaps I'd clarify a bit. I'm not asking what historical aircraft were 1st to reach the milestone, but what the countries might've done to reach that milestone earlier than it was historically so.

The American trio of P-38, P-47 and F4U were the first 400 mph fighters with good armament.

Fw 190 was the 1st.

 

[Shortround6]

Kind of depends on if you mean the first to hit 400mph in service condition or the first to hit 400mph in prototype form with much less armament than later production versions would carry.

The Fw 190 was all over the place in the development stages. different engines, different wing, and not really first class armament until 1941 or so.

Granted it took the F4U until about 1942 to finally mature with about 800 changes from the XF4U.

 

[nuuumannn]

Fw 190 was the 1st.

Ahem...

Heinkel He 100 - Wikipedia

 

[tomo pauk]

Ahem...

Heinkel He 100 - Wikipedia

It was, but it still does not tick the boxes I've listed at opening post.

 

[tomo pauk]

To start the ball rolling.
For the UK, Spitfire might be the best bet. The changes vs. historical early Spitfires: fully covered main U/C + retractable tailwheel (+10 mph?); better carburetor (again +10 mph?); more sloped windscreen (?? mph). Use of 100 oct fuel - 5-10 mph? Relocation of oil cooler in front of oil tank? More streamlined exhausts - copy the idea from Bf 109D from Spanish civil war -for another 7-8 mph? Use internal BP glass vs. external for smaller speed loss.

RAE, in it's technical note no. Aero 1273 states that an 'ideal Spitfire I' (= less draggy exhausts, conical windscreen, casings' ejection chutes flush with wings, no ice/mud guard on air intake, no rear view mirror, but still with old carb, without the covered U/C and with fixed tailwheel, radiators as-is) should be capable for more than 380 mph.

 

[tomo pauk]

For Americans:
- the P-44 gets build with R-2180 (that also gets better development & production) of 1500 HP
- NAA P-509?
- a bit smaller P-39 with 4 MHGs
- something like American Sea Fury, but with 2-stage R-2800 A series
- a V-1710 powered fighter with a 'proper' turbo installation
- early R-2800 + turbo powered fighter

 

[nuuumannn]

It was, but it still does not tick the boxes I've listed at opening post.

Yes Tomo, I was highlighting the He 100 because it flew before the Fw 190, not to add it as qualifying for the premise of the thread, but yes, it doesn't really meet your criteria and if it had a conventional cooling set up and all the gubbins needed for a frontline fighter in the late 1930s/early 1940s its arguable that it mightn't have been able to reach 400mph.

 

[tomo pauk]

Yes Tomo, I was highlighting the He 100 because it flew before the Fw 190, not to add it as qualifying for the premise of the thread, but yes, it doesn't really meet your criteria and if it had a conventional cooling set up and all the gubbins needed for a frontline fighter in the late 1930s/early 1940s its arguable that it mightn't have been able to reach 400mph.

A fighter dimensioned as He 100 (it did have a slim fuselage that was not too tall; small* and, by the looks of it, thin wing; flush-fitting air intake, and fully covered U/C) with leading-edge radiators or the annular radiators might've still come in close to 400 mph? Not having the airframe serving as the cooler frees a lot of space there for guns & ammo.
On the other hand, the Bf 109F was also well streamlined (if not perfect), yet it still needed a fully-rated DB 601E to make 400 mph.

* 2/3rds of wing area of Spitfire or P-51

 

[nuuumannn]

Not having the airframe serving as the cooler frees a lot of space there for guns & ammo.

Which all adds weight of course, then you have the ducting for coolant and the radiator design. Not saying it definitely won't reach 400mph as the He 100 was very streamlined, but these things would affect its speeds, that's for sure.

 

[Dash119]

Not having the airframe serving as the cooler frees a lot of space there for guns & ammo.

I believe the surface/evaporative cooling was primarily in the wings, not the fuselage. So you can add guns in the wings if you switch to a conventional radiator.

 

[Shortround6]

I believe the surface/evaporative cooling was primarily in the wings, not the fuselage. So you can add guns in the wings if you switch to a conventional radiator.

The engine coolant was primarily in the wings. The oil system used a heat exchanger in an alcohol bath/tank with the alcohol surface radiators in the turtle seck, the horizontal stabilizer and the vertical fin. The fuel was also primarily in the wings.

 

[Zipper730]

They were even faster when the balkenkreuz was applied.

Where did that myth start that the Germans were scientific gods or something?

 

[SaparotRob]

I have no idea. It was the United States that developed THE aviation milestone. Ray-Bans.

 

[tomo pauk]

Which all adds weight of course, then you have the ducting for coolant and the radiator design. Not saying it definitely won't reach 400mph as the He 100 was very streamlined, but these things would affect its speeds, that's for sure.

Yes, the weight creep was acute for any aircraft of ww2, in percentage probably more than in was the case with big aircraft, like big bombers. Although, weight much more affected RoC and maneuverability than it affected speed (not that I'm making any great discoveries there).

Where did that myth start that the Germans were scientific gods or something?

A thread of its own

 

[Shortround6]

Yes, the weight creep was acute for any aircraft of ww2, in percentage probably more than in was the case with big aircraft, like big bombers. Although, weight much more affected RoC and maneuverability than it affected speed (not that I'm making any great discoveries there).

I think (but could be wrong) that it was the early WW II aircraft (mid/late 30s designs) that suffered the greatest weight creep (or gallop). Not only for the introduction of self sealing tanks and armor but increased armament and often newer, more powerful engines.
Some bombers went through enormous weight increases (B-17 for instance?) even keeping pretty much the same engines. Almost 25,000lbs?
Some later bombers/attack aircraft showed much less "growth". A-26 started with 2000hp engines in design and first flight and kept them until the end of production. Later rebuilds got more powerful engines and much increased gross weight but that was post war. The jump (for the allies anyway) in fuel and and engine power was occurring in 1939-41.

For fighters like the F4U, F6F and P-47 gross weight in "fighter" condition (clean= no external stores) didn't increase by huge numbers as they had protection from the start, gun armament stayed pretty much the same and the engines didn't change in weight too much. Not saying there was no change but compared to early vs late P-40s or the Spitfire the changes were small.

 

[tomo pauk]

Soviets:
The MiG-1/3 was almost there. At least the prototypes, that series-produced examples were incapable of following due to the combination of bad fit & finish (especially once Germans come in knocking) and attempts on increasing firepower with adding either under-wing guns or rockets. The problematic canopy sliding mechanism led to the pilots flying with canopy open, that badly hurt the speed.
Introduction of emergency ejection system for the canopy might be a short term solution until the more permanent fix is made. Having two Shvak cannons from day one means there is no need to spoil the streamlining the fighter by addition of 'external' firepower. Fit & finish improvement might need Stalin's intervention

Another aircraft that might come in close to 650 km/h is the M-71-powered fighter. The I-185 pushed the 'big engine in small airframe' concept to the practical limits, so probably less of a handful would've been something like the LaGG-3 airframe with that engine. La-5 with M-71 thread here.