Quote: Angus: "I do have an account of a P51 ending in a sustained stall turn at tree-top level. With one notch of flap, the 51 out turned the 190. The 190 pilot took the clever way out, zoomed to a standstill and bailed."
Yes, and I do know of another similar account, where the FW-190A's wingtip caught the three tops after being matched or slowly gained on by a Merlin P-51 in at least four consecutive on-the-deck 360° turns... Though in that account the speed might not have been sustained even with the 4 full 360° turns, as the speed at the moment it caught the threes was so high that the FW-190A STILL bounced on the ground and cartwheeled several times over a long distance, DESPITE the 4 consecutive 360° turns...
Something to keep in mind is that usually all these three-top fights with escort fighters FOLLOW a continuous dive from 25 000 ft., so the speed at the start of turning could be extremely high, and still be well above 250 MPH after as many as four full 360° turns.
You have to keep in mind the IMMEDIATE, and large, deterioration of the FW-190A's turn rate above 250 MPH, a speed still well below the maximum sustained turn rate ability of many other fighters. Above 400 MPH however, the disparity narrows down a little between most fighters, except apparently, in the 190A's case, to the right... (Also the FW-190A's disparity in high dive speed pull-outs is even larger still...)
Another factor to consider is pilot experience, where in the case of one Merlin P-51 account, the FW-190A followed him around in a low speed turn, matching his turn rate, but according to the US pilot: "Snapping his wings all the way aroung the turn as he tried to follow"... The P-51 ended up the victor with flaps-down and the prop set on coarse pitch at very low speeds...
This could be due to a lack of "patience" in fighter pilot's lingo: Trying to gain too much too quickly, and as a result constantly "catching" the FW-190A's violent wing drop all the time, and thus creating drag. This could easily happen due to overeagerness or a lack of pilot experience: Other aircrafts, such as the Spitfire, "rumbled" instead of snapping one wing violently down, and this may have been more "newbie"-friendly for getting maximum turn performance at low speeds.
The final point that may cloud the issue is the FW-190A variant involved: The A-8 was THE major advance over all previous models, in both turn rate, initial level speed zoom and acceleration, yet that aircraft could often be a heavily armoured bomber-destroyer version. Even the use of four 20 mm cannons could make a big difference. The fact that Luftwaffe pilots cared about the FW-190A's low-speed handling is reflected by the VERY common removal of the outer 20 mm guns... Another major issue is the use of the broad-blade wood prop, which was a bit limited in availability even late in the war... So compare a four-20 mm guns FW-190A-6 at 1.42 ata with a narrow metal prop, or a two-20 mm gun FW-190A-8 at 1.58 ata with a broad wood prop, and it is a significant difference from some early 1944 accounts compared to some late 1944 ones...
With the broad wood prop, this specialized low-speed turn fighter had little to fear apparently: "I feared no other aircraft in my FW-190A-8" said a FW-190A Western ace, an "ace" in P-51 kills, that would always, in his accounts, downthrottle below 250 MPH, and pop the flaps, to prepare AHEAD of a low-altitude fight with P-51s... The counter to "hit and run" tactics in this case would have been to force a series of head-to-heads, which usually favoured the FW-190A... "The FW-190A eagerly makes frontal attacks" as the Russian combat evaluation observed...
As you can see in the ranking I made earlier in the thread, there is, from what I saw in 600 combat reports, little difference between a P-47D Razorback with paddle-blade prop and, say, a narrow-blade FW-190A-5. The Merlin P-51 should be MUCH worse than either with the flaps up, but as you will find in many accounts, it could become almost equal to earlier narrow-blade FW-190As, and even GAIN on Me-109Gs, by dropping the flaps and setting the prop pitch to coarse below 200 MPH. Here the Merlin's extra power at these low speeds allow it to maintain a stable speed even with the drag of the flaps that should be the downside of using flaps: Losing more speed than you gain in radius.
This coarse-prop-pitch/flaps-down below 200 MPH is a very common, and successful, Merlin P-51 tactic at VERY low speeds (the flaps alone also help at high speeds), but in the words of one RAF Polish pilot, "It made the stall even more dangerous". I still don't think the Merlin P-51 could compete at all at low speeds with an optimized FW-190A-8 with wood prop, and even earlier FW-190As would give it trouble, especially with only two-20 mm guns and an experienced pilot...
Quote Krusty; "Horsepower alone won't make a plane turn. Usually the higher powered planes are much heavier, and fight a lot more torque, and the lighter (slower) planes turn much better. Seems to be the case in almost every WW2 plane that gained power in later versions during the war."
-It's not a simple cut-and-dried matter, but where turn RATE is concerned, more power WILL get you more turn rate, while lighter, lesser power planes will have a tighter RADIUS. Note that despite a generally crummy turn RADIUS, the Merlin P-51 often defeated the smaller turn radius of the Me-109G-6 with a better speed retention during a horizontal turn (a slight downward spiral helped the 109G-6 compete), resulting in faster turn RATE. But sitting on the "outside" of the 109's turn, P-51 pilots often describe having great difficulty "concluding" without stalling or "swinging" the nose inside their turn. (One P-51D pilot tells of almost stalling seven times on the deck, in a continuous turn, each time at the moment of firing, before finally hitting his late-war, probably MW-50-equipped, 109G target)
The use of flaps is not such a great bonus, because what you get in radius you lose in turn rate...
Turn rate is generally more tactically important than turn radius, which is why the notion of the MW-50 equipped Me-109G-14 being WORSE turning than the Me-109G-6 is so absurd...
Gaston
