Cobra trailer stuck closed

I admit to being a little surprised that the manufacturer of these fine trailers (which I mean sincerely) hasn't made some simple provisions in the design (along with a standard design for a lifting rig using off-the-shelf components) such that mere mortals could open the lid and replace the gas spring. The risk of messing this procedure up is pretty substantial.

Maybe they have such a design and procedure?

Andy Blackburn
9B

So you want to take work away from mechanical types?!?!
LOL........

Yea, this is sorta a "no win" if the struts fail, especially if the glider is still in the box.

But hey, what would MacGuyver do?

And yes, most front hinged trailers have a VERY heavy top without the gas struts helping.

On Monday, June 11, 2018 at 5:52:20 PM UTC-6, Andy Blackburn wrote:
I admit to being a little surprised that the manufacturer...

Consider yourself fortunate to not know how sausages are made...

See ya, Dave

Just catching up with this thread now and finding the very belittling response by Steve to my suggestion deeply insulting!

Well Uli, I'm sorry you were insulted by me. As an engineer, I'm definitely not good at dancing around an issue and trying to make people feel good that are 100% wrong on technical matters. But aside from being sorry about hurting your feelings I also think you brought it upon yourself by doubling down and citing your credentials instead of getting to work on google and figuring out how the damn things work when I first rang the alarm bell for you.

Anyway, I'll buy you a beer when we meet someday.

You are good at ignoring evidence that doesn’t suit your opinion though.

I had the strut on my Komet "fail closed" and it took a lot of time and pressure to extend. I assumed the bleed hole/valve was blocked somehow, the end result being the gas trapped on the shaft side of the piston.
Fortunately the other strut was working which made manual recovery possible.
Cheers Ben

On Saturday, June 9, 2018 at 7:42:23 AM UTC-4, Auxvache wrote:
Anyone have any experience with the gas strut failing in the compressed position? My 2002 fiberglass top didn't quite open fully on its own in March, so I ordered replacement struts. Unfortunately, the next time out the top only opened a few feet, then progressively less as I tried to lower and then raise it. Now it is stuck closed and will not open even a crack despite two people hauling on it. Did I mention the glider is still inside? I can't get to the strut from the front door with the fuse and wing in the way.

So, I'm trolling for ideas on how to force the top open without damaging something. Thanks in advance.

Dissuaded from plan A (stuffing the trailer with helium balloons) and plan B (a small explosive charge), I was lucky enough to find a friend with a hoist mounted to the ceiling of his hangar.

We used a 2x4 and small straps to distribute the lifting force on the handles. Hoisted it enough to get the top propped, then disconnected from the handles, moved the trailer back a little, and put a long 2x4 across the inside, hooked the ends with straps to the hoist, and lifted some more. (FWIW, there's not much room behind the rudder as the top gets higher.) The stuck strut put up a commendable fight, and after three feet or so there was a pronounced tilt toward the affected side.

Maybe we should have waited longer to see if it would gradually hiss open, but instead I crawled inside and unbolted the strut from its top attachment.. None of the awful things I was picturing happened, and the strut stayed compressed. Removing it completely, we were interested to find that the whole cylinder had expanded enough to make getting it out of its square sleeve difficult. It eventually accepted defeat and getting the new one in was easy enough.

Thank you again all for your helpful suggestions! Happy flying.

Thanks for the update, Auxvache! Glad you didn't have to resort to plan 'B'.

.... and the strut stayed compressed.
Steve - insert the sound the little birdie makes, when it comes out of the clock, here! ;-)
Uli
'AS'

On Thursday, June 14, 2018 at 7:03:27 AM UTC-4, AS wrote:
Thanks for the update, Auxvache! Glad you didn't have to resort to plan 'B'.

.... and the strut stayed compressed.
Steve - insert the sound the little birdie makes, when it comes out of the clock, here! ;-)
Uli
'AS'

If you took pictures, that would be a good article for Soaring.

we were interested to find that the whole cylinder had expanded enough to make getting it out of its square sleeve difficult.

Any ideas what caused this? Rust? Gradual deformation over time (I haven't seen that before)?

I dealt with a few strut failures on an older Komet trailer where the gas springs were mounted externally and exposed to road grit. But the gas springs in my 26-year-old Cobra are still going strong, in part--I suspect--because they're mounted in the correct orientation and are protected inside the square tubing, which is inside the trailer. But I've never actually inspected them.

Chip Bearden