Flying with low/flat strut

O

Oopsie

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We had the right main oleo go flat on us on the Piper. Seems to be an upper seal leak (won’t hold nitrogen). We can add 200psi of nitrogen and get under the wing and jiggle it and it won’t hold once we step on the wing. The strut is basically flat, maybe 1/4inch showing if that. Problem is, our mechanic can’t get to it for a few weeks and we need to fly on some trips. I’ve seen people fly with flat struts before, but not sure what we should do or know. If we take it easy on the landings, is it likely to do damage?
 
Do it yourself under owner maintenance before you wad it up.

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Advice for Owner-Performed Strut Service | Piper Owner Society

What happens when the Piper Owner Society puts its mind to a maintenance problem? An extremely detailed look at Piper struts. This discussion is from the Piper Owner Society forum at piperowner.org/talk. Please note that a member supplied 3D printing files so you can create your own...
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Oopsie said:
We had the right main oleo go flat on us on the Piper. Seems to be an upper seal leak (won’t hold nitrogen). We can add 200psi of nitrogen and get under the wing and jiggle it and it won’t hold once we step on the wing. The strut is basically flat, maybe 1/4inch showing if that. Problem is, our mechanic can’t get to it for a few weeks and we need to fly on some trips. I’ve seen people fly with flat struts before, but not sure what we should do or know. If we take it easy on the landings, is it likely to do damage?
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Do you promise to only make smooth easy landings?
 
A hard landing or a bump in the runway could send quite the shock into the spar without the strut cushioning it. Could it cause (or initiate) damage? I don't know, but I also don't want to find out.
 
Landed and felt the right side noticeably drop a few seconds after touching down. Really odd feeling. It wasn't a hard landing but my first thought was that a tire had blown even though it didn't feel like that. It was the strut and the right side was about 4-5 inches low. I sent a photo and then called my A&P. He said to fly it home and make the smoothest landing of my life. He said it was a risk to land without the cushioning effect, but it wasn't worth having him drive 50 miles to repair it in situ. Frankly I wouldn't fly my airplane with a collapsed strut except to get it to the A&P, but your appetite for risk might be more than mine.
 
Not sure what kind of Piper you have but when I owned the Cherokee this happened to me as well. Was a really odd feeling having one side of the plane suddenly sink while rolling off the runway. It didn't need a rebuild for me. The mechanic on the field fixed it. I was over 1,000 miles from home base. I don't think I would have flown it if the local mechanic hadn't fixed it.
 
dfw11411 said:
Landed and felt the right side noticeably drop a few seconds after touching down. Really odd feeling. It wasn't a hard landing but my first thought was that a tire had blown even though it didn't feel like that. It was the strut and the right side was about 4-5 inches low. I sent a photo and then called my A&P. He said to fly it home and make the smoothest landing of my life. He said it was a risk to land without the cushioning effect, but it wasn't worth having him drive 50 miles to repair it in situ. Frankly I wouldn't fly my airplane with a collapsed strut except to get it to the A&P, but your appetite for risk might be more than mine.
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I ran into the same problem, but in my case it didn't drop, it just went clunk. Nothing showed on the strut. So I called the shop (20 miles away) they said go ahead and fly it home (KCFO). Nope, I parked it, and trudged over to the closest of the 3 shops at KAPA. Fortunately, they have multiple A&Ps (my shop only has 3), and they sent the junior intern to tow it to the shop. They said go have lunch and come back in a couple hours. Junior intern watched & learned how to jack up the cherokee, replace the Orings, refill the fluid & air (or N, who knows) then the A&P signed the logbook, I paid the bill and flew home.
 
If the strut is flat what will take the shock out of your landing.
 
That brings a good point, if flying the plane in that condition you should consider lowering the pressure in that tire.
 
AV8R_87 said:
That brings a good point, if flying the plane in that condition you should consider lowering the pressure in that tire.
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Tell ya what, place a call to Piper Aircraft and ask to speak with a Tech Rep. Tell him you are going to operate a Piper with a flat strut because you want to still fly while waiting for a mechanic to fix it. Ask him if lowering the tire pressure would be a recommended procedure to help keep this aircraft operating. :rolleyes1:

Please let us know the reply.
 
Jack up the plane, extend the strut, wrap it with 3/8 inch nylon rope about 4 inch from bottom of strut up. Make it real tight.

** only to be done in emergency .
 
Doc Holliday said:
And what "emergency" can one use to justify flying an unairworthy airplane?
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Immediate danger to someone's life, for example.

Doc Holliday said:
Let's see, shearing the valve stem to not only have a flat strut, but now a flat tire????
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Even if you shear the valve, the tire won't deflate instantly. Plus, you're at a place where maintenance services are available so you can have both fixed.

MauleSkinner said:
How would low tire pressure make it better?
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Drive your car over some rough roads at the recommended pressure, and then lower it by 10-15% and drive it again. See how that feels.

Lindberg said:
Less likely to rupture the tire from overpressure due to the lack of other shock absorption?
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Also less likely to damage the gear bolts or the spar.

I wouldn't fly it like this under normal circumstances, but if it's an emergency I might consider it.
 
Doc Holliday said:
??? Please explain?
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Use your imagination. What would you consider immediate danger to someone's life?
Doc Holliday said:
It won't? I guess those tires I replaced the tubes in that sheared the stems out on the runway and went flat was just an anomaly?
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Which part of "instantly" are you having trouble with?
Did those tires you sheared the valve stems off deflate in the blink of an eye? Or did that happen over a non-instant period of time, in the order of seconds/tens of seconds, giving you enough time to safely bring the plane to a stop?
 
AV8R_87 said:
Which part of "instantly" are you having trouble with?
Did those tires you sheared the valve stems off deflate in the blink of an eye? Or did that happen over a non-instant period of time, in the order of seconds/tens of seconds, giving you enough time to safely bring the plane to a stop?
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It doesn’t take long enough to bring the airplane to a stop.
 
MauleSkinner said:
Note that your emergency authority doesn’t extend to a takeoff.
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The way 91.3(b) is written, you are most likely correct. Not that I'd care if it was an actual emergency, like someone in need of urgent medical attention or an angry mob chasing us.
 
Oopsie said:
We had the right main oleo go flat on us on the Piper. Seems to be an upper seal leak (won’t hold nitrogen). We can add 200psi of nitrogen and get under the wing and jiggle it and it won’t hold once we step on the wing. The strut is basically flat, maybe 1/4inch showing if that. Problem is, our mechanic can’t get to it for a few weeks and we need to fly on some trips. I’ve seen people fly with flat struts before, but not sure what we should do or know. If we take it easy on the landings, is it likely to do damage?
Click to expand...
As others have pointed out: Flying with a flat strut is a bad idea. I wouldn't do that with my piper (also: when I bought mine it had 2 low struts that got serviced right away).
I think an easy solution is to find another mech with better availability to address it. It's a routine job that doesn't cost an arm and a leg, and will allow you to fly safely without abusing the airplane for convenience sake.
 
AV8R_87 said:
Immediate danger to someone's life, for example.
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"Springfield Tower, I need an immediate takeoff, no time to explain!"

cat-dressed-as-pilot-sitting-cockpit-airplane-holding-steering-wheel-with-his-paw_671318-1355.jpg
 
AV8R_87 said:
But if it was an emergency that required the plane to be flown, might as well make things a bit better.
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In all my time, I have only ever read about or heard about one emergency takeoff, in a book from a Vietnam OV-10 pilot. He landed to refuel and rearm when the airfield was closed. With troops in contact and needing his services, he declared an emergency and took off to go back to support the guys on the ground.

I highly doubt anyone in a Cherokee in the US would ever have a situation dire enough to require an emergency takeoff.
 
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