Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: df54 on April 30, 2009, 04:14:08 PM
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Read Corky Meyer:
At the Joint Army/Navy Fighter Conference on October 16, 1944, I tested the P-38L dive-recovery flap well in excess of its 0.65 Mach-number limit. Upon actuation, they instantly provided a smooth, 4G recovery without pilot effort. Immediately after I evaluated these "jewels," they were installed on all Grumman 17817-1 Bearcat fighters.
No pilot effort--the nose pitched up from deployment of the dive recovery flaps--around 10-20degrees pitch up.
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The AH2 P-38L has the dive recovery flaps.... They just don't work....
Manual trim, trimmed neutral. Dive from 20k, throttles to idle, deploy recovery flaps before compressing... P-38 dives straight into the ground.
My regards,
Widewing
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IIRC, the L's flaps only work after you have compressed. I also heard somewhere that they will help you turn within a smaller margin.
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IIRC, the L's flaps only work after you have compressed. I also heard somewhere that they will help you turn within a smaller margin.
If you dive from 20k, you will be locked up in compression very quickly. Deploying the flaps before or after entering compression makes no difference. You have to use elevator trim to recover.
Any thought that they improve turning is an illusion. They do nothing but add a small amount of drag.
Test it yourself offline.....
My regards,
Widewing
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P-38L, Spawn from A3 SW in the TA, 30k air spawn over A1...dive down, don't use dive flaps, and can still maintain timing so I can pull out right before I hit the ground :D
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P-38L, Spawn from A3 SW in the TA, 30k air spawn over A1...dive down, don't use dive flaps, and can still maintain timing so I can pull out right before I hit the ground :D
And your point is...
The point the OP and Widewing have made, I believe, is that the P-38s dive brakes do not work the way they should.
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First off, compression should not be an issue below 20K feet, but it is. You should not even need dive flaps below 20K feet.
Second, the dive flaps, and they are dive flaps, NOT dive brakes, do not perform as they are supposed to, in any part of the flight envelope
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First off, compression should not be an issue below 20K feet, but it is.
How so? Are you saying that the P-38 cannot exceed critical mach below 20,000 feet?
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How so? Are you saying that the P-38 cannot exceed critical mach below 20,000 feet?
In real life, yes.
ack-ack
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since this is a major bug in the fm will hi tech fix it. After all we are all paying for accurate flight models.
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It appears that dive flaps arent extending at all. The light in cockpit is on and auto trim on manual. No extension through keyboard command or button mapped on joystick.
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They retract automatically above a certain speed, from what I've heard.
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They retract automatically above a certain speed, from what I've heard.
The Fowler flaps retract, but the Dive Recovery flaps do not.
My regards,
Widewing
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In real life, yes.
ack-ack
What's the in-game issue then?
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since this is a major bug in the fm will hi tech fix it. After all we are all paying for accurate flight models.
I got my game for free.
:D
I pay $16.02 a month for online access to the arenas.
wrongway
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In real life, yes.
ack-ack
In real life, the P-38 was restricted to 20 mph above placarded limits (460 mph TAS), or 480 mph TAS from 20,000 feet and below. This was due to buffeting and nose heaviness, even with the Recovery flaps deployed. The Recovery flaps would initiate a nose-up tendency that would force the pilot to push the yoke forward to maintain the dive. Hands off, the Lightning would pull out unassisted.
I must retract my statement that the Recovery flaps do not work... They work, within the realm of where the P-38's manual states they should work.
Flying level at 20k, I rolled into a steep dive with the Recovery flaps deployed. I was trimmed neutral. Buffeting began at 460 mph TAS. I still had good elevator control at 500 mph. Climbing up to 20k again, I dived once more. As the aircraft began buffeting, I released the stick and it pulled out by itself, the g meter indicating nearly 4g. Speed reached a peak of 499 mph.
I climbed to 25k and repeated the dive. This time, speed peaked at 511 mph and the aircraft was sluggish in responding to the recovery flaps, but I did have enough elevator authority to ease out of the dive. Note that 511 mph TAS was the maximum I was able to attain during the dive.
Using the P-38J, I repeated the 25k dive test and was not able to exceed 511 mph TAS again. However, a lot of trim was required to pull out of the dive.
Thus, I conclude that the Dive Recovery flaps do what they are supposed to do IF you keep your air speed below 500 mph TAS. Also, they do absolutely nothing if you don't trim manually. The auto-trim will counteract the pitch-up tendency with down elevator.
Finally, the Dive Recovery flaps will not help you if you wait too long to deploy them. Deploy them as soon as you begin the dive. A 4g pull-out requires about 5k to avoid hitting the ground. Moreover, if you are already at max speed (about 511 mph) when you deploy them, you will not pull out below 5k without reducing power and using some elevator trim.
My regards,
Widewing
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since this is a major bug in the fm will hi tech fix it. After all we are all paying for accurate flight models.
As I mentioned before in this thread and in many others, there is no bug with the dive flaps in the P-38L. They work.
ack-ack
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Thanks Widewing. I'd heard this from Fester... :P
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Looks like Widewing covered it well.