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Joined: 8/20/2006 From: Boston,
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yeah it's tall grass at the end of the runway which can be a pain on retracts, but better for the bird overall when hitting hard... Usually if the landing is not coming together I add power slowly and go around...but in this case(my first) the plane touched down, rolled for 10 ft (wet grass, lot's of drag) and then became airborne again suddenly...so when I tried going around again she torqued over and cartwheeled. I guess I have never been at that slow of speed before and in the air!
..also just need to come in more in line with the runway and crab it like you say.
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Joined: 9/26/2002 From: Evans,
GA, USA Status: offline
It sounds to me like the plane just came in too hot, and with the strong crosswind it was extra difficult to manage. You probably should have aborted the landing before the plane first touched down. That said hindsight is 20/20. I'm glad to hear that your plane will live to fly again! You may want to think twice about flying the 'Stang in that strong a crosswind, at least for a while.
Minnflyer, this particular plane is extremely light on the wing for a warbird and it tends to balloon and float without any sink. So you pretty much have to fly it to the ground tail-up and then allow the speed to bleed off before letting the tail drop. I've found that adding nose wt helps to reduce ballooning which makes landing a whole lot easier to manage. It is possible to take this too far on most planes, but because of the position of the retracts on the H9 P-51 ground handling becomes a big problem long before there is too much nose wt.
I also lift the flaps soon after the plane is on the ground. But I agree that you can't wholly rely on this to keep the plane from going airborne again.
Walt
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VQ P-61, H9 150 P-51, D-F Decathalon, NEA Twin Air, Duellist, Nobler, GP 60 Extra, Arrow racer, LT-40.. the hanger is full!!
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Joined: 8/20/2006 From: Boston,
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Cool little video there of the landing! Yeah it really takes a while to slow down. I guess it was not a good idea to run the idle higher either! But I have been trying to "fly it in" as much as possible and flair at the last second which makes it even hotter....I used to come in a lot lower and flair longer...but I heard the warbird should descent around 45 degrees, using throttle management and then flair with a bit of up.
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Joined: 9/26/2002 From: Evans,
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The gear are set back far enough where the plane wants to nose over if the balance point is at all forward of the recommended cg. So in order to add nose wt the gear has to be raked forward.
I've had two of these planes now with different engines and various balance points. My experince is that moving the cg behind recommended (more wt on the tail) makes landings very difficult, and weight on the nose helps stabilize it. I attribute this to the low loading for the wing design and the relatively short elevator coupling.
Walt
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VQ P-61, H9 150 P-51, D-F Decathalon, NEA Twin Air, Duellist, Nobler, GP 60 Extra, Arrow racer, LT-40.. the hanger is full!!
Posts: 121
Joined: 8/20/2006 From: Boston,
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Hey
Just got back from flying...less wind today... But still a 7mph cross wind which helped me work on my crabbing! Getting better at it. Still it really likes to flair a long way. I do have a 32 oz tank which makes it more nose heavy at take off...but it seems to balance quite fine I feel right at the CG recomended. I have not tried shimming, but I'm not sure if I need to?
My last two flights though my left robart retract collasped on me...never had this before..but it popped up again a second later...like the lock didn't catch or something the first time. When I check it was locked though. It happened exactly the same twice in row. I checked it after the first time and could not find any issues...then it happened again. Now I'm not sure what to make of it. Still looks totally locked and solid??? Gave it a few good whacks to see if I could unlock it manually but it didn't unlock that way either.
Matt
< Message edited by Hello82 -- 12/13/2006 5:09:50 PM >
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Joined: 3/12/2005 From: Fort Collins,
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Well, I'm a bit poorer, but the new H9 80" P-51, and its Saito 2.20, are now sitting in my shop waiting for me to get started!
If you're interested, or you're building one of these yourself, I just opened up a build thread at New H9 1.50 P-51 Build. Lots of pictures over there, but tossed in the "just unpacked the box" one here for grins.
I'll be starting on her tomorrow, but only the usual boring stuff like reinforcing the firewall and wing mount plate. But, if I have time, I'll also do a preliminary mount of the Saito to see how it fits. I'm curious to see the modifications needed to the chin cowl to accomodate it, as well as the Pitts-style exhaust I expect to use.
Warning: I'm a slow builder, even with an ARF! My planes tend to exhibit "feature creep" from my various mods (eg: my H9 60 P-51 has flaps; that mod alone ran almost 30 hours), so I suspect others buying this 'Stang may be done, and in the air, well before me.
Heck, it's winter, anyway, so what's the hurry!
See you on the build thread!
Bo
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Joined: 5/31/2004 From: san francisco,
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a tip for ya Matt on the retracts my smaller robarts were sticky and were not locking or retracting smoothly I took them apart, cleaned and lubed them with air tool oil and have not had any problems since, it seemed to me the grease in the piston was gummed up and was not moving enough to lock.
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RE: Hangar 9 150 Size P-51 - 
