P51 Questions and Answers

[Scott - A2A]

Q: My aircraft performs badly at high altitude

A: In these aircraft -- for normal climb and cruise operations -- you'd normally set the mixture to either auto-rich or auto-lean and then leave it alone. Some folks seem to like to play with the mixture control so, unlike the WoP bombers, we set up the engine to have an active mixture control IF the customer wants to use it. The fact is that it is virtually impossible to properly set the mixture for optimal power at altitudes above 10,000 feet in Flight Simulator -- the mixture control just doesn't give you enough control without massive amounts of finicky attention paid to the thing. This is what you are experiencing.

We suggest setting your realism to "automixture" which, in reality, is much closer to how the actual aircraft would operate. The aircraft will always make optimal power this way. Alternatively, if you want to edit the aircraft.cfg file, you can set up your aircraft to have automixture by changing the value in the "automixture" line to a "1" instead of "0". This can be found in the engine section. Back up the file, of course, before editing.

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Q: I can't slow this thing down! Help!

A: Any problems you are having bleeding off speed are going to be related to one of three things, and we are listing them here in the order that they would most likely be culprits:

1. Your approach is much too steep and you are not flying a proper pattern.

2. The aircraft is too heavy for a normal landing.

3. Your throttle is not properly calibrated.

4. All of the above is also possible.

This aircraft flies exactly according to the actual P-51 manual and bleeds off speed precisely as it should. Throttle settings and airspeeds during approach are exactly what the manual calls for. There was one individual who indicated the aircraft would not fly at less than 250 mph! Clearly there is a throttle calibration problem there.

Reading the checklist is a must. There are very specific instructions on how to set up for a landing, but we'll repeat them here. (These are practically verbatim from the P-51 manual, and your WoP Mustang will fly exactly as these instructions specify). Remember that a proper approach is a three-degree glideslope at a rate of descent of ~500 fpm. Any faster descent rate than that means you have set up your approach wrong and you'll never get slowed down enough to make a proper landing unless you have a very long runway. Our development team not only flew in two separate P-51 aircraft as passengers, we interviewed many P-51 pilots, both civilian airshow jocks as well as two of the last surviving P-51 double-aces from WWII. We also flew countless approaches to confirm that the WoP flight model was an exact match to the real aircraft. So if you are having problems, evaluate the three reasons indicated above, and follow the checklist. The P-51 is not a training airplane, it is one of the hottest piston fighters in the world, and it's unrealistic to expect to hop in it and be able to fly a beautifult textbook approach, whether you are a real-life pilot in a real P-51 or a sim pilot. As we've mentioned, most flight models out there have drastically high amounts of flap drag that are completely unrealistic, which has caused people to become used to "having the airbrakes slammed on" when the flaps are put down. This flight model is accurate and correct and will perform just as the manual indicates. Take your time and learn to fly the plane, make sure you're properly set up, and calibrate your controllers. The pilot of a real P-51 has a far more complex job than we sim pilots have, but we still need to check aircraft weight, fuel supply, and fly by the book.

Landing

Check tanks and select the fullest tank for landing.
Put the fuel booster on normal.
Check the mixture control and set to RICH.
Set the prop to about 2700 RPM.
Check the traffic pattern and obtain clearance to land.
Slow down to a sensible speed before peeling off.
Slow down to 170 mph before lowering your landing gear. When the landing gear comes down, the airplane gets quite nose-heavy. However, you can easily adjust the trim tabs to take care of this. Don't forget that the gear takes 10-15 seconds to go down.
The normal speed in the traffic pattern with wheels down is 150 mph IAS.
Do not lower full flaps before 165 mph IAS. Remember, it takes 15 seconds to go from the full up position to the full down position. Allow plenty of time for this operation to make sure your flaps are down when you need them.
After your flaps are down and you roll out of the turn onto the landing (approach) leg, your speed should be about 115-120 mph IAS. Don't keep so much power on that you'll be making a power approach. However, keep enough power on to keep your engine clean (about 20-25 inches of Hg on final at a descent rate of 500 fpm at 120 mph IAS at 9,000 lbs. aircraft wt.) Just before getting to the runway, break your glide, make a smooth roundout, and approach the runway in a 3-point attitude.
Hold the plane off in the 3-point attitude just barely above the runway until you lose flying speed and the plane sets down. The P-51 doesn't mush but stalls rather suddenly when you lose flying speed. So have your plane close to the runway at this point.