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True.
The P-51 had small wings whitch gave them areadinamics.
The P-47 was teh best diver though.
Yes it could.
The Me-262 and Me-163 had problems at high speed.
They broke up and somtimes exploded.
The P-47 didnt realy unless you give the engine to many RPMs, whitch you can avoid by lowering the pitch.
You cant do that in a Me-262 or Me-163.
Yes it could.
The Me-262 and Me-163 had problems at high speed.
They broke up and somtimes exploded.
The P-47 didnt realy unless you give the engine to many RPMs, whitch you can avoid by lowering the pitch.
You cant do that in a Me-262 or Me-163.
I agree with Kürfurst.
Messerschmitt 109 - myths, facts and the view from the cockpit
Diving - structural rigidity of 109 in dives
The Me 109 was dived to Mach 0.79 in instrumented tests. Slightly modified, it was even dived to Mach 0.80, and the problems experimented there weren't due to compressility, but due to aileron overbalancing. Compare this to Supermarine Spitfire, which achieved dive speeds well above those of any other WW2 fighter, getting to Mach 0.89 on one occasion. P-51 and Fw 190 achieved about Mach 0.80. The P-47 had the lowest permissible Mach number of these aircraft. Test pilot Eric Brown observed it became uncontrollable at Mach 0.73, and "analysis showed that a dive to M=0.74 would almost certainly be a 'graveyard dive'."
- Source: Radinger/Otto/Schick: "Messerschmitt Me 109", volumes 1 and 2, Eric Brown: "Testing for Combat".
- (Comment: it seems Eric Brown's analysis is flawed, though, and test pilot Herb Fisher performed 150+ such dives: an example of a 0.79 dive. Several of the dives achieved Mach 0.83. Sources: Herb Fisher, Herb Fisher Jr., and Curtiss-Wright.
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I have read part of this report before, from Capt. Brown. The Spitfire that achieved .89 Mach had the nose case ripped from the engine and the wings were bent slightly backwards. Sorry, but I think that plane was beyond "redline dive speed".
I love the Spitfire, don't get me wrong, but I just don't see how it can dive faster than a P-51.
There are a number of ways of delaying the increase in drag encountered when an aircraft travels at high speeds, i.e., the transonic wave drag rise, or of increasing the drag-divergence Mach number (the free-stream Mach number at which drag rises precipitously) so that it is closer to 1. One way is by the use of thin airfoils: increase in drag associated with transonic flow is roughly proportional to the square of the thickness-chord ratio (t/c). If a thinner airfoil section is used, the airflow speeds around the airfoil will be less than those for the thicker airfoil. Thus, one may fly at a higher free-stream Mach number before a sonic point appears and before one reaches the drag-divergence Mach number.
The Spitfire use in this test was a special prototype prepared specifically for this test, and it had experimental laminar flow wings (a-la Supermarine Spiteful).
In actual service trim the highest official recording of compressability during dive was for the Mustang at 0.8 Mach, any 'stang could do it and that was exceptional.
A Mustang III Ser No KH 505 was allocated to the RAE for high speed research, and this showed up some unpleasant compressibility effects, and indeed the aircraft was eventually lost in failing to recover fro a high mach number dive, killing the Canadian pilot, S/Ldr. E.B.Gale.
In such dives compressibility effects set in at M=0.71 with a slight vibration of the aircraft and buffeting of the controls, accompanied by a slight nose down pitching moment. These symptoms increased in intensity up to M=0.75 which was the limit imposed for service use. Above M=0.75 a porposing motion started and increased in intensity together with the other effects up to M=0.8, when nose down pitch became so strong that it required a two handed pull force for recovery.
In July 1944 Wright Field test pilots explored the high speed dive characteristics of a Merlin powered Mustang. A series of dive tests were made starting from about 35,000 ft. in a test airplane equipped with a mach meter. The idea was to explore the effects of compressibility such as buffeting, vibration, control force changes, and so on. Initial dives showed the onset of the problem to occur at just under mach .75. Additional dives were made, usiung three test pilots, which carried the aircraft sucessively to mach .77, then .79, and up to mach .81, and finally to mach .83 (605 mph) As the dive mach number was increased the compressibility effects became more violent, but the aircraft wsa still controllable, and it was possible to fly it out of the problem when desired, at mach .83 the shaking and buffeting of the aircraft was so strong that it was decided to explore no further. The airplane had suffered considerable structural damage and was written off.
How did this dive bomber get approved for combat use?
Service Spitfires had a higher limiting mach number than Mustangs. Spitfire manuals note maximum mach as 0.85. The P-51D was limited to 0.7, the P-51B 0.75.
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On the eve of WW2 the P-36A Hawk was the new star of the stables and French speculators were in the 'States to witness flight tests, having already placed a small order with a view to more. With a level top speed of 313mph already outclassed by the latest BF-109 and Spitfire developments in Europe, the French listed a requirement of a 500mph dive speed (!). H
Lloyd Child flew it on Jan24 1939 from 22,000ft in a dead vertical dive like it was a walk in the park, when it reached 500mph he started counting, considering pulling out at eight but deciding it was still flying so smoothly he'd continue...to seventeen and 5000ft for a 7g pullout. The recording instruments indicated 600mph at 9000ft!!
That's 0.813 Mach. Unsurprisingly the French not only placed further orders for the type, but increased them.
Hallion notes that the pressure sensitive equipment of the time may not have been entirely accurate, but still there can be no doubt the Hawk well exceeded its 500mph dive requirement. The part that gets me is the test pilot, Child, who decided okay, they want me to break 500mph in this baby well I'll do that and then count to seventeen in a vertical dive...
Child tested a total of 41 first flights of experimental prototypes in his career before retiring, testing several models for Curtiss.
About this time the new XP-38 and XF4U-1 Corsair were being developed which could accelerate too quickly in vertical dives so the Navy flight test guidelines of "zero lift vertical dive through 10,000ft altitude loss" was of course altered in line with advancing aircraft technological development, particularly when the XF4U-1 was routinely breaking 550mph and overspeeding the engine within these guidelines. Most test flight procedures had been developed during the twenties and had never really been revised.
a little personal amusement, the P-36A clearly outdives the P-47 according to actual flight testing (as opposed to manufacturer claims)...at least in terms of terminal dive speed (certainly not initial dive acceleration I'm not stupid). Still, when somewhen says blah blah P-47 amazing dive I get to say, meh, P-36 is better.