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This document only specifies II./JG11 for provisional testing of the higher boost pressures.
http://www.wwiiaircraftperformance.org/me109/db-minute-6730.pdf
I haven't done a complete translation as I need to refer to a German friend who helps me with such things. You can see that the use of 1.98 ata boost is forbidden. There are complaints about fuel quality and a very unfavourable comparison of the Bf109 to the Mustang (in a German document!).
I'm sure I've seen a copy of that 20th March order somewhere. I know Kurfurst's site has a list of units that were supposed to adopt the higher boost. Unfortunately what the OKL was hoping for and what the units were being advised to do are not the same.
Just a week earlier Reparatur-Anweisung 2. Nachtrag Nr. 191/345 from Des Reichministers für Rüstung und Kriegproduktion,dated 14 March 1945,gives instructions for the adjustment of engine settings and it clearly gives 1.8 ata as the maximum boost allowed.
Some units would have received this instruction for higher boost after Bf109 production had ceased and they were receiving old G-6s from training units.
I've been looking into this over the last few days. Ther is no evidence proving operational use of 1.98 ata by any combat units. The one unit that we know experimented with the higher boost pressure, II./JG 11, was disbanded during the first few days of April,probably at the same time as several units of Luftflotte 6 (to create a reserve!) and some from Luftflotte Reich and Luftwaffe Command West.
'Interner Aktenvermerk Nr. 6642' from Daimler-Benz dated 17 Jan 1945 reports on a meeting held 10 January 1945 at OKL, Berlin. All 4 DB 605 DC engines supplied to Rechlin from DB-Genshagen failed (pistons, piston rods, supercharger). It states that 1.98 ata boost pressure is not to be allowed for combat units.
'Die Sondernotleistung DC (1,98 ata Ladedruck) für die Truppe nicht freigegeben.'
It is inconceivable that combat units would have been using it earlier.
Niederschrift Nr 6717 from Damiler-Benz, dated 19 January 1945, states that DB 605 D engines from Kassel are delivered at 1.80 ata boost
None of the units flying K-4s for 'Bodenplatte' were operating 1.98 ata boost.
Ratsel you can fly your simulations with what ever engine configurations you choose but in the real world they didn't exist.
Cheers
Steve
Hello George
my info is
for Bf 109G-6, 1,42ata is the Start- und Notleistung, ie Take-off and Emergency power, allowed for 1 or 3 minutes, depending on the manual you looked, 1495hp,
530km/h at SL 640km/h (398mph) at 6.600m. With MW50, if this was installed later on, ie in practice G-14, 570km/h at SL
109G-10/R6 bad weather fighter with autopilot with Combat and climb power (30min) 500km/h ? at SL, my copy is so dark that I'm not sure on the last digit, 655km/h at 9000m. Max speed with Sonder 562km/h at sea level, 690km/h (429mph) at 7500m
K-4 (max 1.8ata / 1800hp)
combat and climb power (30min /1275hp at SL) 515km/h at sea level, 670km/h at 9.000m
Max with Sonder 580km/h at SL, 710km/h (441mph) at 7.500m.
Juha
Hello George
in the tread More complete english translation of Major Kozhemyako - Topic
in the message by Buzzsaw- on Tue October 04 2005, 09:54 you can find good info on tactics used over Eastern Front by 109G-2 and Yak-1b pilots and also speeds used, not exactly late war but in 43 and early 44, but very informative analyze on tactics used by LW and VVS fighter pilots at that time by a VVS combat veteran.
Juha
His conclusions about German tactics, do not agree with german pilots memories.
The P-51B/C/D had excellent roll rate at high speed because of internal balancing of the ailerons in which pressure from the deflected aileron is channeled to a belows that relieves loads. The thick wing of the P-51 had room to fit this equipment as well as to be made quite stiff. The FW 190 had a high roll rate becuase of the stiffness of the two spar wing, the thinness of the wing tips and the use of friese ailerons which scooped air from the opposit side to reduce force and prevent adverse yaw. Again note that the Me 109F + had Friese ailerons unlike the Me 109E, it also had differential ailerons in which upper deflection is about twice as great as downward deflection.
Another factor which hurts roll rate is inertia coupling: an aircraft does not fly along its principal axis; hence when it rolls the weight at the nose and tail tend to be centrifuged outwards. This was not well understood during WW2 but caused a great many problems with early jets (super sabre). I suspect the lower roll rate of the FW 190D over the FW 190A was caused by this; hence hydraulic boost was brought in.
Interesting theory - and the 109D certainly added mass moment arm for nose, but no additional weight for tail - just extension of moment arm due to the plug. Any analytical evidence to support the theory? With the same waing as the Anton, your thesis is interesting
The Me 109 may have had wings that compressed such that the ailerons stiffened but in its favour was a short span, stiff wings that did not twist and short body with the weight close to the center of lift and with a long tail momment arm; all factors which help roll rate.
We also know that late model Me 109s outdived P-51D's We 'know this' how?
I really would like to see a chart and measurments or at least a simulation.
"Aeroelasticity" is a new one to me, but, if the Spitfire wing was so weak, how did 2nd TAF manage to hang a couple of 250lb. bombs under the wings of the IX, XVI XIV? As far as I remember the 109 could only carry a single bomb under the fuselage. From the Mk.I, inspections were introduced to check for wrinkling of wings after heavy manouevring; only if the leading edge D box showed signs, or the rest of the wing had wrinkles above 1/10", was the wing changed.
Edgar - Aeroelasticity was a very poorly understood science in WWII. But it is about the fact that even stiff torque boxes defelct under load and the deflections create interesting aerodynamic and structural effects.
A Spit manuevering with 250 pound bombs is a completely different beast from a Spit in level flight.
The Spit I through IX had the same basic wing/aileron combination. At 400 mph the spit ailerons were about 35% effective raech control reversal at approximately 550 TAS. The P-47 at 400mph was about 65% effective and the 51 about 70% - which is wht the P-51B/C/D out rolled bot (and the Fw 190) ~ 400 mph. The wing twisted under the eccentric aileron loads for all of them, but least for the 51,
.
The only WWII aircraft that could possibly suffer from inertia coupling would be the Bachem Natter, and I don't believe it ever flew long enough to get into the phenomenon.
Others might suffer from aeroelasticity, such as rolling to the opposite direction when applying full aileron at very high speed (the F-86 did that), but not from intertia coupling. To get to intertial coupling, you would need a very fuselage-heavy aircraft with small, highly-loaded wings. I believe inertia coupling was first seen in the X-1A and X-2. It got yeager in the X-1A, and he spin out of control ... but he recovered. It killed Mel Apt in the X-2.
The Do 335 qualifies in the heavily-loaded fuselage category, but not in the small, highly-loaded wing category.
Opinion, Drgondog?