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slappedsilly
03-27-2007, 04:45 PM
I've been flying the p51d in the 4.08m version and it seems much better than before. My biggest foe is myself as my wing likes to come off at 690kmh to 740kmh. I read on the net that its max speed dive speed should be around 813kmh (though I didn't see at what altitude) My question is, are all the versions in the game the same when it comes to the structual failure of the wings?

slappedsilly
03-27-2007, 04:45 PM
I've been flying the p51d in the 4.08m version and it seems much better than before. My biggest foe is myself as my wing likes to come off at 690kmh to 740kmh. I read on the net that its max speed dive speed should be around 813kmh (though I didn't see at what altitude) My question is, are all the versions in the game the same when it comes to the structual failure of the wings?

horseback
03-27-2007, 07:20 PM
It may not be failure of the wings so much as you exceeding the G-limit by applying too much elevator. The Mustang's controls are very light, and the controller system in this sim is force based (as in how much force the 'pilot' is applying to his stick) rather than how far he is moving it.

It doesn't take a lot of movement on your stick to de-wing yourself at high speeds.

cheers

horseback

MrMojok
03-27-2007, 07:22 PM
In the controls menu, reduce the curve for your elevator deflection. Make it top out at say, 90% instead of 100%.

badatit
03-27-2007, 08:01 PM
At 820-850kph or so (memory is a bit fuzzy), the ailerons can/will pop off of the wings if your not careful. Only done this in the 20NA. I imagine they are all similar. IL2 compare list max dive as 890kph for all 51's.

I've never had it up to 890. But I've had it up to 870 (and I was holding my breath, while reducing power) with out any breakage.

GH_Klingstroem
03-28-2007, 03:16 AM
Another tip for all the P51 models is to use LOTS of trim ALL the time!
The P51 was famous for requiring lots of trim at just a slight speed change.
That said, in a dive, as the speed comes up u need to start trimming. U will feel the nose wanting to come up so u need to trim the nose down! Once you have done this, the wing breaking will almost vansish! I know what im talking about, since I fly the p51 ONLY now a days and have become really good in it. I havent broken the wings for a looong time! Also remember to trim rudder as the speed comes up, but thats another story...

Feel free to ask lots of questions about the P51, I know her like I know my... uhm.. anyway..
I just feel she is the least understood plane in the game! I would gladly help you online with some tips how to fly her... just give me a time and we will sort something out!
cheers

slappedsilly
03-28-2007, 10:06 AM
Thanks for the input. My only other question is about convergence. I fly most turn and burn planes at about 180-190 conv. When I fly the mustang I use about 220, because my speed is so great when attacking I feel I will ram them if I don't pull out early. What do you use?

horseback
03-28-2007, 11:20 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by GH_Klingstroem:
Another tip for all the P51 models is to use LOTS of trim ALL the time!
The P51 was famous for requiring lots of trim at just a slight speed change. </div></BLOCKQUOTE>When you speak of the in game Mustang, I would agree with you, but actually, no, <span class="ev_code_YELLOW">the REAL Mustang was NOT known for needing lots of trim compared to its contemporaries</span>.

Every (and I mean every) pilot memoir from the 1943-45 era comments about the Mustang being an easy to fly and control aircraft. No whining about excessive trim, or how it made the pilot workload greater.

In fact, it was the exact opposite. An effective trim system was a great convenience that lessened the pilot's workload, especially for a long range fighter.

The fact is that most aircraft of the era lacked anything like accurate trimming; a pilot had to compensate for this lack by applying constantly changing rudder or aileron inputs to fly straight and level at any but a few speed ranges. After an half hour or so, it could begin to wear you down. An aircraft that could be trimmed so that it flew straight and level without constant adjustments was considered a great step forward.

The Mustang was most often compared to the P-40 series of aircraft, which were absolutely trim hogs which did require trim adjustment for speed changes of less than 10mph; in combat, the Warhawk pilot HAD to add trim during sharp turns or risk being overcome by high stick or rudder forces and stalling out.

From America's Hundred-Thousand, by Dean (pp 248, 249):

TRIMMING
A major aspect of flying the P-40 series airplanes was handling trim changes from power and speed changes. A veteran AAF pilot stated "The trim changes with speed were more than in other contemorary fighters."..."every power and speed change brings an immediate trim change which the pilot must either counteract or trim out." The H87 (P-40E and later series-HB) was, if anything, worse than the H81 Tomahawk.


The Soviets flew a lot of P-40 variants during the Great Patriotic War, and it is likely that Oleg and his team rely heavily on Soviet sources for their flight modelling. How does the in-game Tomahawk and Warhawk compare to the above description?

The Allison versions of the Mustang were usually referred to as much faster and much more refined than the Warhawks they would have rapidly replaced were it not for two things: Curtiss' politically entrenched place with the War Department, and the discovery that putting a Merlin in it made the Mustang a superb long range high altitude fighter (ie, the Holy Grail for the western Allied Air Forces). North American's production was wholly consumed with producing the P-51B/C models, which left Curtiss's P-40 series safe from replacement with A-36/P-51As until the Merlin engined Mustang versions completely took over frontline duties.

Again, from Dean's America's hundred-Thousand, this time from the section covering the Mustang (pp 340, 341):

TRIMMING
<span class="ev_code_YELLOW">ALLISON Mustangs were particularly notable for lack of required trim changes.</span> Power or flap setting changes gave only small trim variations, and the same was true of gear retraction. The changes in tab settings for climbing and diving were negligible. Tab settings were sensitive and had to be used carefully.

Trimmability was also quite good in the MERLIN Mustangs, and tabs were sensitive. In these versions directional trim changed more with speed and power changes...Along with trimming the airplane for longer term steady flight conditions, <span class="ev_code_YELLOW">some</span> pilots trimmed their aircraft almost continuously to wash out any high stick or pedal force during maneuvering in combat.


How does that stack up to the in-game Mustang?The in-game Mustang handles much like I would expect the P-40 to, just faster, and I must question how or why this is so.

Again, Oleg and his team were heavily reliant upon Soviet sources for their flight models, but the Soviets received only 10 examples of the Mustang Mk I and NO flyable examples of the Merlin versions as flown in the shuttle raids.

Their most likely source of a flying Mustang was China, after the communists seized power, and the Nationalist Chinese who originally operated them were legendary for their maintenance shortcomings. Any Mustang coming to the USSR in the postwar period from the east would be unlikely to be in good repair, and the only other examples they might have gotten their hands on would have been rebuilt wrecks from either the Germans or their own territories, and we know how all kinds of problems arise with taking these tests/comparisons too seriously.

I suspect that if the Mustang's FM is accurate, it is MORE accurate in the unforgiving and pilot workload direction than 90% of the FMs of the other latewar fighters.

The Mustang was one of the most (if not THE most) aerodynamically refined aircraft of its era. Requiring constant or excessive trim adjustment/inputs <span class="ev_code_YELLOW">compared to its contemporaries (as in other high performance single engine fighters)</span>simply doesn't seem logical to me, particularly when the flight modelling makes trim inputs as imprecise and delayed as this game does.

cheers

horseback

OMK_Hand
03-28-2007, 01:51 PM
"I leveled off and asked for some nose down and left rudder trim. I saw that any change in power or airspeed would require some rudder trim; it was sensitive to that. I opted to just hold some rudder so I wouldn't bother Lockwood with a trim request every few minutes."

http://www.warbirdaeropress.com/articles/MissA/MissA.htm

(For every action, there is an opposite and equal re-action )

"Care should be taken not to impose excessive loadings by too rapid recovery from the dive, which might overstress the aircraft."

Mustang III Pilot's notes.

"The directional trim changes as speed and horesepower output are varied. The trim tabs controls are sensitive and must be used very carefully to prevent overtrimming."

"The airplane is limited to a maximum positive load factor of 8G...
A max. negative load factor of 4G...
These only apply at 8000 gross weight...
8 x 8,000 pounds = 64,000 pounds being supported by wings...
Greater than 8000 pounds weight = for max G: divide 64,000 pounds by new gross weight...
With external loads = 5G max...
All this for a straight pull-out.
For a rolling pull-out: max G = 2/3rds of the max G for a straight pull-out for the weight..."

P-51D flight handbook.
Flying and surviving is all about numbers.

bluedragon1950
03-28-2007, 01:57 PM
~S~ GH_Klingstroem,

When and which server do u normaly fly? I'd like be your wingman so I can record some tracks for study?
I'm from Virginia, USA.

TY

horseback
03-28-2007, 02:10 PM
Backseat occupied by an adult male in a postwar modded Mustang is a lot like having a full fuselage tank. Trim might be a bit different without someone sitting there, and full gun & ammo trays...

Again, this is a modern pilot used to more forgiving and less powerful prop aircraft of a later generation. Does this individual have a companion piece covering his experiences in a restored 109 or 190?

If so, does he note how much he has to adjust his stabilizer trim, how much pressure he had to maintain on the stick and rudder to compensate for the aircraft's natural tendency to pull away from straight and level flight? Does he compare it unfavorably to a Cessna 172?

Look up Jeffrey Ethell's magazine pieces (Flight Journal, I think) on flying the P-40, P-51A and Merlin Mustangs. He made a point of specifically comparing them to each other in the P-51A piece and it is quite illuminating.

The Mustang can fairly be considered a bit trim hungry and torque-y compared to modern high powered turboprop trainers or jets, <span class="ev_code_YELLOW">but the issue is how it compared in that regard to the top single engined fighters of WWII.</span>
cheers

horseback

OMK_Hand
03-28-2007, 02:16 PM
Granted, re: two seater. Please see edit above.

Xiolablu3
03-28-2007, 04:26 PM
I am pretty sure that this wing break is actually a result of hte P51 picking up speed so d*mn well in a dive compared to other planes.

Before you know it you are over 850k and pulling out hard much over that will result in a break.

It used to be much worse, now you only really lose a wing if you forget to keep an eye on your speed in the dive. It used to happen in almost any high speed vertical dive.

Try to keep an eye on your speed in hard dive. The plane doesnt 'talk' to you and warn you like other planes do. Its still flying smooth with no buffeting over 850 where a FW190, Spitfire, Me109, Hellcat,P47 or Tempest are buffeting and shaking like crazy. Or when the Lavockin LA, Yak, Ki84, MOsquito (!) and Zero have broken into many little bits.

OMK_Hand
03-28-2007, 06:01 PM
More bits and bobs.

From the Mustang III notes:

Except when carrying full fuselage tank, the aircraft is stable longitudinally, laterally, and directionally. When the fuselage tank is full, the aircraft is longitudinally unstable in all conditions of flight, and tends to tighten up in turns; until at least 40 Imp. gallons (48 U.S. gallons) have been consumed from the fuselage tank, no manoeuvres other than very gentle turns should be attempted.

Maximum weights:
Take off from prepared runways or good grass airfields, 11,250 lb.
All forms of flying, 9,300 lb.
This weight (9,300 lb) includes full guns and ammunition and full permanent wing fuel tanks.

From the P-51D Notes:

Abrupt pull-ups should not be attempted with more than 25 gallons in the fuselage fuel tank.
No aerobatics are permitted with fuel in the fuselage tank.

Avoid rapid movement of the elevators in dives and manoeuvres at speeds above 350 mph IAS or .7 Mach, particularly at aft CG positions (with fuselage fuel), to prevent rapid uncontrolled increase in G-loads.