Best German fighter for the Eastern Front

[Erich]

JG's 300 and 301 were also in the west after the order to send Reich defence gruppen to the Ost front post January 15, 1945, though the mentioned JG's also fought against Soviet forces. the same can be said of the LW NF force several gruppen fought on both fronts.,,,,,,,,,,,,,the figure of 480 NF's is hypothetical at best, as it is still unclear though having on hand what condition what were they in.

 

[delcyros]

The G-10 might be the 'poor mans K-4' but its performance was more or less the same as the K-4.

Both, the G10 and K4 had DB-605 derivates with high altitude optimised supercharger (Db-605 ASM/ASC), which had less power at medium altitude (except the 2000hp DB-605DCM running at 1.98ata) than the Db-605 AM of the late -G6 and standart -G14.
There is little to choose from a MW-50 boosted G6/-G14 (on 1.7 ata) and the -G10 or -K4 (1.8 ata) in the low to medium altitude range interested here (G14 beeing slightly faster). The performance difference exist - but at altitudes larger than 5500m, where the -G10 and -K4 clearly are faster.

Compared with the many late -G6, and -G14 aviable, how many servicable La-7 had the VVS at it´s disposal in 1945?
The january ´45 list gives 298 La-7 (all of them with 2x 20mm Shvak), increasing to 798 planes at may 9th, 1945 (including those serving in Manchuria and Slovakia). Compared to the thousends of La-5F, La-5FN and Yak-9, this number doesn´t appear to be very large.

Working from the performance data of soviet and german sources, respectively, I cannot see where the La-5FN or La-7 outperform the basic Bf-109G6 or -G14 with MW-50 boost and Db-605AM:



(note: MW-30 was initially aviable early in 1944 and soon replaced by MW-50. The Bf-109 figures are on 1.7 ata and B-4 fuel, the soviet figures on increased "forza" power)
The 1945 produced La-7 with 3x Berezin 20mm and further increased low altitude performance was somehow faster at SL and 2 km/h faster at optimum altitude. But then again, this compares unfavourably with Bf-109G and -K derivates on 1.98 ata using Db-605 DCM, which appeared in the same timeframe.

 

[tomo pauk]

Del, the Soviets give better performance values for the La-7 than what can be read on your graf. The 'forsage' is available only in low compressor gear, so in both compressor gears the La-7 can beat the 670 km/h mark.
The K-4 (with 1.98 ata) should beat the 720 km/h mark.

 

[Juha]

...the figure of 480 NF's is hypothetical at best, as it is still unclear though having on hand what condition what were they in.

480 is number of serviceable night fighters but I agree that it is largely hypothetical because usually only the experienced crews flew missions in 45 because of lack of adequate fuel supply.

Juha

 

[delcyros]

Del, the Soviets give better performance values for the La-7 than what can be read on your graf. The 'forsage' is available only in low compressor gear, so in both compressor gears the La-7 can beat the 670 km/h mark.

Yes, but that´s for 1945 and most post war manufactured La-7, not for those which actually saw some (though never much...) service in ww2. The first improved La-7 was manufactured in january 1945 and may or may not have appeared in march or april 45 on front units, though russian sources disagree on this point. Speed figures attained in production trials from 1944 and 1945 manufactured La-7 fall short of those produced in 1945 and 1946 (see below). Keep also in mind, that the speed figures attained in these trials are not corrected for compressibility effects.

 

[tomo pauk]

If it's not too much a problem for you, could you please point me to the tests (somewhere at the Internet , there La-7 pdf was being pointed out on in this forum not long ago). Gordon Khazanov give 612km/h at SL and 658 at 5900m (for 1944 production) and 613km/h at SL and 661 at 6000m (for 1945 production).

Keep also in mind, that the speed figures attained in these trials are not corrected for compressibility effects.

Any good data about that?

 

[GregP]

The charts on the previous page show the K-4 as being rpetty fast, but don't show that it was flying in a straight line when going that fast. To fight, it had to slow down to under 340 mph or the pilot wasn't going to be doing much maneuvering.

So,the K-4 pilot can run TO and fight or FROM one, but isn't fighting much at anything above 340 mph, and he was working hard at the 340 mph. The P-51 and La-5/7 were still maneuverable at 400+ mph, as was the Fw 190 ... at least in roll.

This is the primary reason I maintain the Bf 109 was "long in the tooth" ... the basic handling flaws were never fixed and it was saddled with the same handling in 1944 - 1945 as it had in 1940. The heavy ailerons and elevator at high speeds COULD have been fixed but weren't, and trim could have been added to both aileron and rudder and weren't. There was really no excuse for NOT fixing the simple issues. Even if they never fixed the narrow-tack gear, the trims and high speed forces could have been worked.

If they had been fixed, it would have been a premier fighter to the end. Who knows, they may also have done quite better than they did late in the war.

 

[stona]

Slightly veering away from the topic but to change the landing gear track on the Bf 109 would have involved a major redesign. Surely other issues (like trim tabs operable by the pilot) could have been easily addressed.
Cheers
Steve

 

[GregP]

If some of the basic issues had been fixed, it would have remained right near the top of the fighter heap. It remained solid, but gradually lost ground to other designs as they matured and faults were corrected.

Another case of "could have been ..." but in THIS case, it "should have been."

 

[Milosh]

Late war 109s had a Flettner tab on the rudder which eased the forced required by the pilot. Flettner tabs were tried on the ailerons but received mixed reviews by pilots but certainly increased the roll rate.

 

[GregP]

They'd have to fit a trim in order to really help the rudder load, not just a Flettner tab, though that probably DID help a lot. Still, without trim, the pilot would have to hold rudder pressure even with the tab.

I can't see why aileron and rudder trim were not fitted since all the WWII aircraft I know of, except for the Fw 190, exhibit strong trim changes with speed. For some reason the Fw 190 doesn't seem to have much pitch change with speed changes. All the rest DO, and in all axes. That's from Planes of Fame pilots who fly a lot of different warbirds.

I know of at least ONE warbird pilot who landed with the trim tab when his elevator control failed in flight. I bet that was a hairy few minutes. If the Bf 109 rudder or aileron control failed in flight, you'd probably have to step over the side for a nylon letdown, assuming you could get the speed down a bit with elevator so bailing out was possible.

 

[Milosh]

All the control surfaces of the 109 had a trim tab. They just weren't adjustable in flight.

The 190 had +2/-3 degrees of cockpit adjustable pitch change for the stab.

Not all WW2 fighters had cockpit adjustable trim tabs for all 3 axis.

 

[GregP]

Yah, I know, but most had both rudder and elevator. The Cadillacs had aileron trim, too, especially if the trim changed with speed. Most stable aircraft are trim sensitive.

Heck, go trim a Cessna 172 at 110 knots and then try to slow-fly at 60 knots without retrimming. You'll be pulling pretty hard just to fly level!

In something like a Sea Fury, you can't hold it level without elevator trim. Ditto the P-51, which is VERY trim sensitive.

 

[tyrodtom]

I remember when I was taking flight training in a 172, I complained to the instuctor about all the trimming I was having to do.
He let me try different speeds without trimming, he heard no more complaints from me.

 

[delcyros]

If it's not too much a problem for you, could you please point me to the tests (somewhere at the Internet , there La-7 pdf was being pointed out on in this forum not long ago). Gordon Khazanov give 612km/h at SL and 658 at 5900m (for 1944 production) and 613km/h at SL and 661 at 6000m (for 1945 production).

I received years ago, either from Crumpp or Henning the source for the tabulated data presented here:
[urlhttp://www.desertstar.co.uk/warbirds/http___www.btinternet.com_~fulltilt_PerformLa5La7.pdf[/url]

They also pointed me to the problem that the russian file contains indicated airspeed readings but no discussion of position error or compressibility effects. Even though compressibility is not to much of an issue at around 600 km/h it contributes to errors of roughly 8 to 12 km/h.
In this, these production trials are not exceptionally exotic. German production trials, for that matter, didn´t differentiated too but noted whether or not compressibility was included. However, then again, some didn´t mention this, too (e.g. Bf-109F4 on 1.42 ata attaining 670 km/h was most likely not accounted for compresibility).

 

[GregP]

Hi Milosh,

Fixed trim tabs are not very user friendly and are mostly set at the factory.

As I'm sure you are aware, I was talking about adjustable trim tabs. The trim changes a LOT in flight for most WWII fightgers (even bombers for that matter). The Bf 109 in particular really needs an adjustable rudder trim tab. It never got one. It also never got enough fuel, a decent canopy with good visibility all around, and never did have the control force leverage ratios adjusted so you could get good high speed handling. All these things were very possible and should have happened during the war.

That does nothing to detract from the war performance it exhibited, but it could have been much better. Then again, so could the Hellcat, which wasn't progressively improved beacause it might interrupt production, so it wasn't just a German thing ... it happened everywhwere because there was a world war on at the time. It is quite possible the production pressures for Germany were far and away higher than for the USA, and that goes along way toward explaining things ... but there were so many versions with so many different modifications that some of the basic faults should have at least been explored in prototype form. I KNOW they made several with wide track landing gear and several with radial engines ... why not fix the real faults while you are at it?

 

[stona]

Hi Milosh,

Fixed trim tabs are not very user friendly and are mostly set at the factory.

Later,often adjusted at the squadron for the Luftwaffe.

While everyone is pointing out the problems with fixed trim tabs on German aircraft it's worth remembering that aileron trim on the Spitfire involved hammering the trailing edge of the ailerons!

Cheers

Steve

 

[riacrato]

I have read comments from German pilots complaining about a lot of deficiencies of the 109: landing gear, lack of control at high speeds, view to the rear... i don't recall anyone ever complaining about the lack of inflight adjustable trim. Seems to me like a feature you don't miss if you don't know it exists. German pilots were used to having to work the rudder when speed changed. The "airfoiled" horizontal stabilizer also helping to reduce the problem.

 

[tyrodtom]

I think you meant to say airfoiled vertical stabilizer.

 

[Civettone]

I have my doubts about the controls freezing up at high speed. They were very heavy, but it seems to me that this was more a problem for the Allied post-war test pilots than for the Luftwaffe pilot, who were used to it. I do not believe that they simply froze.

The Bf 109F has always been described as a near-perfect fighter plane in terms of handling (in the air). With max speed of 660 km/h, I fail to see why a Bf 109G-14 with a similar maximum speed would suddenly be a flying like a brick?

Kris