This is the place where the majority of the warbird (aircraft that have survived military service) discussions will take place. Specialized forums may be added in the new future
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Wed Jun 10, 2009 7:43 pm

Dan Jones wrote:
Holedigger wrote:How big a problem is that getting to be with these older FLYING warbirds? It really is a big safety issue as well as a cost issue. If getting "new" tires are being put off until they really need to be replaced, that is a problem! Small batch production "boutique" tires is an expensive thing as the market is so small. I read that our local Starfighters demo team is babying their supply of tires because of cost and short supply.


I wouldn't start jumping to conclusions. There's a dozen reasons tires blow out besides from being worn. Could have run over some FOD, or had a brake problem, sliced off a valve stem... I doubt very much that the airplane was flying around on bagged-out tires. The Stearman Restorers Association was recently able to get someone to make new production 10.00 SC tailwheel tires after the old molds were accidentally scrapped some years ago. They're Chinese, but a little work removes the obvious evidence.


Thanks stearman guys, we popped ours on sunday.............Ordered one from Desser on monday.

Wed Jun 10, 2009 8:41 pm

warbird1 wrote:If that was indeed "Ruff Stuff", then our own WIXer, "gunnyperdue" is one of the pilots. I wonder if he was flying it when this happened? If he happens to be reading this, or anyone knows, some questions on the "runaway prop" scenario on the P-38:

1) Do the prop blades go to fine pitch on the P-38 in a "runaway prop" scenario?

2) Can you fully feather the prop blades on a P-38?

3) If you happen to get a "runaway prop" situation while airborne, what is the correction action? Can you use the bad engine, or do you shut it down?


If "gunnyperdue" is reading this, hopefully he can give his insight on what happened with some details.


1) it prob would go to a courser pitch causing more drag, it would all ready be in fine pitch for take off

2) YES, it is a twin engine plane

3) according to the POH, hold the control in decrease, if that does not work, use the feather control to lower the RPMs to where you want them then select normal.

Wed Jun 10, 2009 8:51 pm

Any prop that is overspeeding is physically going to fine pitch. Just because the prop control is full forward (for fine pitch) does not mean the propellor is at the fine pitch stop. As the engine reaches full rpm, and also as the airplane accelerates, the prop naturally comes off the fine pitch stop in order to avoid increasing rpm.

Also, a prop going to course pitch does not increase drag, it reduces it by a small amount, until it is feathered, then it reduces it a great deal.

Wed Jun 10, 2009 8:54 pm

warbird1 wrote:If that was indeed "Ruff Stuff", then our own WIXer, "gunnyperdue" is one of the pilots. I wonder if he was flying it when this happened? If he happens to be reading this, or anyone knows, some questions on the "runaway prop" scenario on the P-38:

1) Do the prop blades go to fine pitch on the P-38 in a "runaway prop" scenario?

2) Can you fully feather the prop blades on a P-38?

3) If you happen to get a "runaway prop" situation while airborne, what is the correction action? Can you use the bad engine, or do you shut it down?


If "gunnyperdue" is reading this, hopefully he can give his insight on what happened with some details.


I haven't heard the details of the incident, I wasn't flying it, Rob Ator was. Have had problems with one of the props in the plane... the rpm just keeps going, it can be controlled by using manual and/or the feather button... you can fully feather the prop... it takes 45".... if you can control the prop/rpm don't shut the engine down... as I said it has happened to me in Ruff Stuff... not a huge deal if caught in time... don't know the details, sorry.

gunny

????

Wed Jun 10, 2009 9:01 pm

it prob would go to a courser pitch causing more drag, it would all ready be in fine pitch for take off

For the rest of us Yankee's low pitch (high RPM) for take-off
and high pitch is low RPM
According to 20th FG pilot and cool dude Art Heiden.........
If a generator was lost or a low battery the Curtis Electric prop would lose the Dynamic Brake and go to extreme Low Pitch. This was called a RUN AWAY. It could happen on Take Off with a low battery. Since you couldn't feather it set up a lot of drag making it difficult to make it around to land. The Killer situation was to lose the Generator or lose the engine with the Generator on it while 2 or 3hrs into Germany. Procedure was to SET the Props then turn off all electrical power. Then momentarily turn it back on to reset the props as needed. Being sure everything electrical was also turned off -- No Radios.

Wed Jun 10, 2009 9:11 pm

Thanks for the info gunny and jack - most informative!

Wed Jun 10, 2009 10:54 pm

Holedigger wrote:Good text book description from here
http://www.auf.asn.au/groundschool/propeller.html


Thanks Holedigger.

retroaviation wrote:I'm glad the P-38 driver recognized it and was able to stop the airplane with no further damage.
Gary


Agreed. Gary, can I can assume on a twin engine aircraft like the P-38, immediately shutting down one engine could cause it to bank sharply to one side?

P-38 at Fairmont, NE.

Fri Jun 12, 2009 8:58 pm

I was at the Fairmont show and saw the P-38 incident. The runup seemed to be normal and healthy followed by runway lineup. Full power was applied slowly with normal acceleration, but I noticed at about 1/3rd down the runway that he wasn't rotating. At about the mid point of the runway we saw lots of smoke coming from the aircraft as it continued towards the end of the 4300' runway. At first I thought this was from an engine, but later learned it was from a blown right tire following heavy braking. Fortunately the plane was stopped before the end of the runway and exited to the right side still on pavement. We later learned the abort was caused by an engine/prop overspeed. The pilot did a great job saving the situation and the airplane. As we taxied out for departure we saw the skid marks from both tires from about the half way point to the end of the runway. I really thought he was going off the end, but as I said he did a great job getting stopped. :D
Jake Fendermen
"Those were the days".

Sat Jun 13, 2009 9:01 pm

The main point here is in parentheses in the title, but the pilots skill and presence of mind is certainly to be complemented.

Doug Ratchford
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