Me-109 turn to right widely said to be poor; any clues?

[mechanic]

 While it is usualy the case that a turn to the right could be harder than the left and also that rolling to the right harder (Note:decreasingly so as the throttle is closed) it by no means means the 109s should never use a right turn. It's a matter of text books and charts rather than practical flying. Using a right turn move in a 109 can be essential and thinking "I can't turn right, I'm in a 109" could mess you up at a vital moment.  Remember not to think about anything other than gravity, thrust, lift and gunnery, leave the text book theories behind at the times when thinking for a few seconds instead of acting will be your undoing. If the worst comes to the worst, roll 270 degrees to the left as fast as possible to replace a difficult 90 degree right roll.

[Gaston]

    Actually, at higher speeds (above 250 MPH TAS), the 109E through G required increasing amounts of LEFT rudder to keep the nose straight, and quite heavily so on the pilot's left leg, leading to constant high speed cruising being extremely tiring to the left leg. Gustav pilots (since, in the 109G, the cruise was getting faster, the problem was getting worse!) would joke about a 109 pilot being recognizable by his overdevelopped left leg... Maybe the problem was alleviated by the rudder-trim equipped tall tail of the G-10/K series... The Zero had the exact same trait, but needed instead RIGHT rudder to keep the nose straight, and this time the more fortunate pilot had a very light rudder at all speeds (emphatically NOT the case on the 109!)...

    This means that above 250 MPH, the 109 rolled more slowly to LEFT, and increasingly so with speed. This was noted in allied evaluations.

    This had nothing to do with torque, but was caused instead by the prop slipstream hitting the left-deflected rudder.

    Historically, above 250 MPH, the 109 rolled worse to LEFT, but apparently ALSO turned worse to right, to the point of being singled out by allied pilots as significant in this last regard. Again, in both cases, this was a prop slipstream issue affecting directional stability, NOT a torque issue.

    According to a detailed Spitfire IX pilot account, most 109 pilots STILL usually preferred to break RIGHT after a diving attack, BECAUSE of the faster roll to this side (He attributed this to torque, but I am sure he was wrong on this point, given the higher speeds involved), this was common to the extent that the slow rolling Spitfires would bank in advance to anticipate this. These right turning 109s would then be easily caught.

    However, the same pilot said that if the diving 109 went to the slower rolling left side, they would usually escape the Spitfires. Though he did not actually say it, it does suggest a faster turn rate to the left than to the right despite the handicap of the slower 109 left roll.

    Note that below 250 MPH, perhaps mostly in climbs and under acceleration, the 109 directional assymetry is reversed and required a much less unpleasant right rudder to keep the nose straight. That was probably not a big issue.

    Other aircrafts had similar assymetries; the Zero mostly turned better to left, as did the P-47.

                                                         The FW-190 turned better to right, flaps down, below 250 MPH, and to left, flaps up, above that.

                                                         The Razorback version of the P-47 rolled significantly slower to left at most speeds, probably because of the propeller air spiral catching sideways on the razor spine.

     ALL powerful single-engine aircraft would show a roll preference OPPOSITE to the prop rotation under climb or acceleration at low speeds (to the LEFT on all RIGHT-turning prop types, and this indeed due to torque), but would reverse this roll preference to the RIGHT side at higher speeds, as the propeller slipstream spiral became more important, and constant, than any torque effect (obviously reverse all this for left-turning props; Gryphon engines, Soviet types etc...)


     Getting back to the turn rate symmetry, IF it turns out to be true, as in several U.S. combat accounts, that the P-51 could indeed reverse the tail postion of a 109G, at higher speeds, in an average of 2 X 360 degrees turns to the RIGHT, while requiring 5 or 6 360 degree turns to do the same to the LEFT, then the choice of turning direction was hardly a small matter given that this bought the 109G something like a whole minute of survival(!).

     Adding to this the fact that the P-51 at higher speeds can demonstrably out-turn even the late Spitfires (450 yds 180 radius to 625), this illuminates even more why the left-turning 109s often survived Spitfires compared to the right-turning ones.

     That despite this, the roll preference still made most 109 pilot choose wrongly the right turn is surprising.

     In any case, according to that Spitfire IX ace, that often made the difference between those 109s that fought on to another day, and those that did not, and this is certainly not academic or theoretical to those involved...

     It would be nice to hear more anecdotes that would throw some light on these flight assymetries and their relative significance.

    Gaston.

   

   

   

   

[Die Hard]

I think this thread only affirms the fact that pilot anecdotes should always be taken with about a pound of salt. 60 year old pilot anecdotes even more so. The only data that should be considered anywhere near accurate is flight test data done by professional test pilots.

[MiloMorai]

I remember reading that P-51 pilots were told NOT to get into turn fights with German a/c. If the turn went more than 180* they were to break off and set up for another attack.

[Chalenge]

Gaston the elevators of the Mustang were always metal. The rudder has always been fabric.

[VonMessa]

First of all, "Dogfights" is a biased load of crap.

Second, without wasting all day at it, there were differences between all 109 models(just like any other aircraft), especially the Kurfurst.

The torque of the "K" completely impacts it's performance capabilities and can be used to manhandle the a/c and make it do amazing things.  I find that right turns are much easier to pull off and tighter when chopping throttle.

[Gaston]

    To begin with, answering Chalenge, according to Tom Cleaver, ALL P-51s ALWAYS had fabric elevators, until models later than the the P-51D-5... I had actually heard that the switchover was much later than that, making the metal-skinned elevators barely present in the WW II European theater. I await to be enlightened on this apparent contradiction.

    These elevators made a big difference in high speed turns and pull-outs above 400 MPH, and may have equalled the 109's superior moveable tailplane above this speed. (The 109's trim was apparently so powerful it could do 7G pull-outs with the pilot not touching the stick...)

    The Spitfire IX pilot mentionning the more common right roll for diving 109s was not from the show "dogfights". Since this show interviews mostly U.S. pilots that saw actual combat, and reproduces the battles with their input, I don't see how that makes the show more biased than the usual U.S. pilot combat accounts. The slower 109 turn to right has surfaced many times, including in the current airshow display circuit, and even during wartime for the similar nose-engine design Ki-61. Cutting the throttle might help, but I have never heard of it from any German account, at least not relating to the right turn issue. German wartime pilots make little mention of the right turn, which does raise the issue of the extent of the difference. It might have been more noticeable from the outside.

     The right turn issue has been mentionned also for the Zero, and more rarely for the FW-190A, whose wing drop would switch sides depending on the position of the flaps. This would switch the 190's best turn side, and flaps were commonly used at low speeds on the 190. Incidently, the FW-190A, like the Zero, and to a lesser extent the 109, was an excellent LOW speed turn fighter, and all tests, including both German and U.S. combat accounts, are extremely clear about this. How this confusion about the 190 got started I have no idea, but it can only mean raw calculated data and some cherry-picked performance tests can bring a lot of confusion... Let's examine why this is for a moment, and how it might be relevant to the 109 vs P-51 debate.

     I.E: In a test against the P-47D-5 with 72" output, the FW-190A-5 would vastly out-turn the P-47 below 250 MPH TAS at 5000 ft.. Above this speed, the P-47D suddenly gained a significant upper hand, RAPIDLY increasing the advantage with higher speeds and/or altitude. This does suggest a fairly high speed peak turn rate for the P-47, if the switchover is so dramatic; definitely it seems to be still improving its turn rate well above 250 MPH, while the FW-190 falls off rather dramatically...

     Against the Spitfire, which was one of the rare fighters that could out-turn the 190 at low speeds, Eric Brown describes the 190A as having adopted a new vertical dogfigthing style, but I think this was based on his experience with early 190 fighting; listen how unconvincing his explanation sounds, even though he describes the tactics of earlier, much lighter FW-190A-3/4s, MUCH less prone to high-speed mushing than later A-8s;

      E. Brown.;" The 190(A-4) had tremendous initial acceleration in a dive, but it was EXTREMELY vulnerable during a pull-out, recovery having to be quite progressive, with care not to kill the speed by "sinking". " This quote is right at the end of his description of the see-saw tactic...

      So the best tactics for FW-190A-4s against the Spit was to use the vertical see-saw, but... even with these lightweights 190A-4s, they had to do SLOW pull-outs because, at the bottom of a dive, their high-speed handling stank so much... You can imagine what the high speed pull-out was like in the much heavier A-8...

      Yet the A-8 was universally recognized by all 190 pilots as the most maneuverable of the entire A series, despite the much greater weight. (If you doubt this, you obviously have never listened to actual wartime 190 pilots...) You can be sure this extra weight and power did NOT improve the high speed handling... To witness(among many);

     http://www.spitfireperformance.com/mustang/combat-reports/20-murrell-2dec44.jpg

     Note the "elongated loop", the complete inability to compete with the P-51 in turns without high-speed stalling on late A-8s (Dec. 2 1944 combat), also carefully note the SPEED; 400 MPH at the end(!), and the 190A-favorable altitudes of 20-10 000 ft.. The 190A was indeed an excellent fighter, but NOT at these speeds. The heavier A-8 improved the LOW speed handling, and was a superior LOW speed turn fighter, probably to the point of being competitive with the Spit XIV at some medium-low speeds, and definitely much better than the Mustang, especially when the A-8 was fitted with long-chord ailerons and a wide-blade wood prop.

     This shows two things clearly in the 109 vs P-51 debate; wingloading is not a reliable indicator of turn performance, this either at low or high speeds (Ie. Spit XIV turn beaten by Mustang at 400 MPH), AND light high speed controls, such as test pilots like to describe for the Spit and FW-190, do not necessarily translate into good high speed turn/pull-out performance. Yes the 190 WILL do a 7g pull-out... eventually! But not if you start pulling below 8000ft at 500 MPH+ speeds; it can take THAT much of an "elongated loop" for the pull-out to suddenly "bite" at the bottom, creating "a much inferior angle of pull-out to the P-47D", to quote the same extensive comparison of a correctly ballasted A-5 to the P-47 D-5.

     To answer MiloMorai, I think prolonged, LEVEL, turn fights, below 20 000 ft., were a bad idea for the P-51 against the FW-190A-8, and were probably an even worse idea CLIMBING against the 109G at these altitudes, but this general recommendation not to exceed 180° turns with Germans fighters was routinely ignored by pilots, and rightly so, if the spiral developped downward at a sufficiently steep angle, which was very often apparently...

    Since at high altitude picking up speed was more natural than maintaining altitude, and that, on top of that, the P-51's one-millionth-of- an-inch tolerance supercharger gave a climb advantage above 25 000 ft., even against most 109Gs(!), it is no wonder the overwhelming majority of the turn-fighting... turned in favor of the P-51. At low altitudes, it was a different story, and there was no 26 to 1 kill ratio for the Mustang there, or dumb bombers-only dictates for the Germans for matter...

    When hundreds of U.S. P-51 pilots ALL say the same thing(see the "WWII Aircraft Performance" site); that they consistently out-turned 109s and 190s, they are not conspiring to lie, however bombastic we can assume them to be; it simply means wingloading calculations do not tell the whole story. The Soviets, with their slower aircrafts and lower combat altitudes, had a very different impression of both german aircrafts, though they did slover with contempt at the FW-190's rapidly declining energy in vertical fighting, and the way it "hung" at the bottom of pull-outs, making it, their words not mine, "a perfect target". Light controls, and a superb dive, simply did not make the 190 a high speed fighter, period. I hope this myth gets buried sooner rather than later...

     To answer VonMessa, all 109s shared generally similar handling characteristics, except the Emil's ailerons, which were vastly improved on at higher speeds by the "F", but lost a lot of performance again in the heavier G (down from 109°/sec to 70°/sec?). Also, at high speeds, torque has little effect because the engine acceleration is so much weaker, and the slipstream spiral so much stronger. When trim-tab-less ruddered Gustavs sped up above 250 MPH, there was never any respite for the pilot's left foot, if he did not want to skid slightly sideways, making accurate and stable shooting, and a steady speed, unlikely... E. Brown; "At speeds above 250 MPH, the lack of a rudder trimmer is severely felt".

     As for flight test data, there is very little that is concrete about WW II maneuverability besides roll rate charts (except two very detailed early-war turn-rate charts shown to me; Me-109E and Spit 1). There is no formula or standards for the curve an aircraft makes in the sky, or how it makes it, or decelerates in it... Constant speed turns times are hardly an indication of how the aircraft will perform in combat... Even basic minimum turn radiuses are extremely rare. Side-by-side tests can reveal those differences, but those are rare, and, unfortunately, one of these is the widely-quoted, and vague, Farnborough tests series, were gun-less prototype wings Spitfires are compared to wing-guns ladden 109s (without saying so!)... Combat is the ultimate side-by-side test in the end...

     Gaston.

   

     


   

[VonMessa]

How, pray tell, are you answering a question that I did not ask?

[Noir]

If you want to know more about the fw190 "myth" that you want to save us from, you'll have to install the bloody game 

[Chalenge]

    To begin with, answering Chalenge, according to Tom Cleaver, ALL P-51s ALWAYS had fabric elevators, until models later than the the P-51D-5... I had actually heard that the switchover was much later than that, making the metal-skinned elevators barely present in the WW II European theater. I await to be enlightened on this apparent contradiction.

    These elevators made a big difference in high speed turns and pull-outs above 400 MPH, and may have equalled the 109's superior moveable tailplane above this speed. (The 109's trim was apparently so powerful it could do 7G pull-outs with the pilot not touching the stick...) 

Cleaver the plastic kit guru? I believe the transition occured much earlier and I will ask someone who will certainly know but I do recall having read the notes on this plane as making the transition to metal during construction of the prototype and not after revision.

[Chalenge]

Sorry but you will have to do better then to cite this individual. There does not appear to be any evidence of a fabric elevator on P51s other then a fabric like molding on plastic kits produced by some model companies.

[Gaston]

     Metal elevators were introduced on the P-51D in February of 1945, according to this site, more in line with what I have often heard than Tom Cleaver's claim of the D-5 being the introduction;

     http://www.mustangsmustangs.com/p-51/p51variants/P-51D.shtml

     
      As for the FW-190 myths, no WW II FW-190A combat pilot would recognize most of the aircraft characteristics described for the A-8 in AHWiki, except for the roll rate, and a vague description of "bottoming out" on pull-outs. U.S. pilots widely and repeatedly pointed out that if the 190 did not begin a high speed dive pull-out at 8000 ft., it was going to hit the ground belly-first; this was not the fault of the pilot; an emphasis was made in one quote that the 109 did not do this.

      The AHWiki description is obviously based on wingloading and aerodynamic formulas; the result is totally opposite in almost all respects to the real aircraft, especially for the A-8 which was the consumate dogfighter. Ask ANY 190 veteran, including the 190A-8 Western ace whose family member posted his interviews on THIS very forum, about five-six years ago... High speed was poison in every way to this aircraft, to the point the veteran described downthrottling and popping the flaps to prepare for a fight against P-51Ds... He then describes turn fighting a P-51D Mustang to the right in two to four 360° turns to reverse a tail attack, shooting it down near the ground.

      It seems the A-8's low speed, low altitude acceleration is a factor in this low speed turn performance, taking precedence over wingloading. (I also have a theory about heavier fighters being more top or tail heavy, thus being more able to yaw the thrust axis into a slanted, and thus slower, airflow, something often described as "hanging on the prop")

      AHwiki makes no mention of the critical broad wood prop option, a major low-speed enhancement according to the above veteran, nor is any mention made of the THREE types of aileron chords available to the choice of the pilot (he chose the longest chord type, enhancing them further by adding spacers on their mounting hinges, to make them even longer and better at "catching" the stall at low speed).

      This is all from this very forum, so I am not making it up... Like all comparative tests I have ever seen, he obviously considered his FW-190 very mediocre for fighting at high speeds, despite the dictum "speed is life", and this even though the aircraft could easily reach them. Unlike the much more fragile, more lightly armed Zero, the FW-190A could well afford to go head-to-head against a faster opponent, so loafing at a lower speed was less of a concern; it could always turn to face an attack. This late '44 veteran said on this forum; "In my FW-190A-8, I feared no other aircraft." He had much less praise for the Me-109G-6 from which he transitioned, probably an aircraft more suited to the Eastern Front.

      In any case, I was interested in finding out about the REAL aircraft's flight assymetries, so a game or calculated figures are not really relevant.

      Feel free to dismiss real pilot accounts as "unscientific", or anything that doesn't fit as "poor piloting"...

      Gaston.

     

     

     

     

[Die Hard]

http://www.youtube.com/watch?v=TFl8X4y9-94

[Murdr]

Sorry but you will have to do better then to cite this individual. There does not appear to be any evidence of a fabric elevator on P51s other then a fabric like molding on plastic kits produced by some model companies.

Chalenge,

Pages 7 and 75 http://trainers.hitechcreations.com/historical/P-51%2051-127-5.pdf  which by the way is posted on the P-51D AHWiki page.  That is not to say that the significance that is being placed on that topic in this discussion is anything short of misguided and misleading.

[BnZs]

Gaston, when you consistently come up with stuff that does not appear on any pilot reports or tests anybody has heard of, and directly contradicts the reports and tests that ARE well known, you are going to get called on it. This is not even mentioning the parts that contradict physics...

For instance, in the case of your FW-190, every test I've ever seen  would has agree that it was rather poor in rate and radius of turn and decent in dives, up to the relatively high speed of 460mph IAS in fact.

Your theorizing about its pull out capacity just does not hold water. Unless you've taken the airplane into the transonic and compressability, IF you can input elevator deflection, then said deflection WILL create forces that will cause a change in pitch and thus angle of attack. This is not even remotely debatable. An accelerated stall was said to be vicious in the Fw, but at 400mph IAS even a heavily wing-loaded 190 would have more Gs available for pullout than the pilot can likely stand, before ever reaching the stall point. (Assuming a clean 1g stalling speed of 127mph IAS for the 190, the 9G stall speed of the aircraft would be 381mph. An airplane leading with its belly would be definition be in a *stall* my friend...boy would it ever!) And according to the tests of captured 190s I am familiar with, elevator forces were said to not be objectionable within placarded dive limits. Surprise, surprise, surprise.

The combat reports regarding Mustang vs. 109 turning are also far from inexplicable. As compared to the heavier *late war* 109s, the Mustang has competitive wingloading, competitive power-loading at high altitudes, as well as lighter stick forces at high IAS and maneuvering flaps that could be deployed at very high speed without fear. These factors, as well as the individual pilot's aggressiveness, G-tolerance, and skill at riding the "ragged edge" easily explain why the fight could be won by the Mustang despite the 109's implicit advantage in sustained turning.