P-51 Main Wheel Bay Doors

[Ivedog]

I read that the main wheel bay doors of the 51 would "bleed" down on the ground after the engine had been turned off and hydraulic pressure was absent... not sure how long it took for them to start opening, but I think it'd be cool to see in AH.  One of those radical attention to detail items that would be a real treat for those who knew about it.

Too hard to put in?    Just a thought.

With that in mind though, it'd also be cool to be able to land & taxi over to the hangar for rearm/refuel without leaving the cockpit.  Possibility?  I think that would open up a very fun aspect to the sim (ferrying aircraft, etc.)

Ivedog

[-blk--]

  It depended (depends) on the quality of the hydraulic system.  If the seals and packings were real good, the doors might never bleed down.  But, since that doesn't happen, it depends on how fast the fluid leaks out.  The Accumulator can retain system pressure, up until some point, at which point the loss of any more fluid will cause a drop in system pressure.  Which is why the P-51 gear doors would leak down.

  I don't remember why the P-51 is always remembered as having the doors that bleed down, since most A/C have something that does (look at a 727 or 737 and you'll see the Krueger flaps have bled down).  I do remember, however, that the earlier P-51's had problems with the gear doors coming open in flight and the doors could rip the wings off the fuselage (the wing assembly is only secured with 4 bolts).  I don't know if the D's and K's would rip the wing off if they bled down in flight, but if they could...  especially since you'd have a real reason to get slowed down and landing if you had an engine failure...

blk  AT

[Pyro]

Hot refueling/rearming is planned.  There will be places at the airfield that you can taxi to to rearm/refuel and continue your sortie.  These spots will be subject to destruction however.



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Doug "Pyro" Balmos
HiTech Creations

[eagl]

I'm not sure that even a "high quality" hydraulic system would preclude door bleed down.

All control surfaces in the F-15E are hydraulic, and all of them except the flaps (due to uplocks) will "bleed down" over time.  The ailerons take only a few hours to droop, and the elevators will drop to full down deflection within a day, sooner if there's any wind pushing on them.  It's a matter of your point of view if you would consider the F-15E's flight control hydraulics "high quality" I suppose, since they're not exactly industrial manufacturing grade precision instruments, but they are rather reliable and have close enough tolerances that the flight control Built-In-Test will often fail an actuator that is still working.


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eagl <squealing Pigs> BYA
Oink Oink To War!!!

[-blk--]

  Eagl...  a high enough quality system would stop the hydraulics from bleeding.  Of course, that'd be a perfect system.  I've only seen one hydraulic system that didn't bleed (and that was a mock up--that had just been overhauled--by the manufacterer...)  So yeah, pretty much all of them bleed down.  

  At the museum I worked at, we were having that problem with the T-38.  The flaps would bleed down to about 5 degrees down in about 2 minutes, then slowly to fully extended.  If I remember correctly, the fix was to safety wire them in the up position.  Perhaps you should suggest that fix for your F-15s   .

  What I always thought was kinda cool though, was that if both flaps bled down, you could push down on one, and the other would retract.  You can do the same thing on simple landing gear systems (Piper landing gear does it real well), in that you let all the gear fall almost all the way out.  Then you push one back into the well--the other two extend.  Pretty cool in an airplane-nerd sort of way.

blk  (AT)

PS-When can we get AH to model that?  How, oh how could you consider AH to be realistic if you don't model the hydraulic system in all it's perks?  Oh yeah, is AH's hydraulic fluid flammable (MIL-H-5606), or is AH going to make the jump to Skydrol?  Or doesn't that matter?

[Ivedog]

Excellent news, Pyro.  Thanks!

Ivedog

[Westy]

Definately good news. It would be nice to rearm/refuel without having to exit the aircraft...let alone auger or die due to lack of ammo.  

--Westy

[Phoenix]

I happen to know that the gear doors bleeding down on th -51 depends on the model.I do believe that the doors were connected to the landing struts on the D models.

If you have any questons on WWII aircraft, let me know. I can give you pretty accurate information, seeing as how I get to work on them almost everyday.

[This message has been edited by Phoenix (edited 11-02-1999).]

[fats]

--- Pyro: ---
Hot refueling/rearming is planned.
--- end ---

Uhhh, imagine the #kill counts after someone flying his fifth rearmed plane...


//fats

[-lynx-]

According to all I've read the doors would always be down (irrespective of the model) whenever the engine was not turning.

Simple really - no engine, no hydro pressure, doors down.

Probably not a perfect arrangement but that's how it was according to the books/pics/everything else Pony related  

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-lynx-
13 Sqn RAF