That SOUND, That WHISTLE, Those GUNS...

[Mike Wissing]

We just fired up an LS3 (with a reversible prop) a few days ago. The hall sensor gave some grief but it sounds great!
They want 40 hours of ground run time before the first flight.

B33E85BB-D393-4B8A-9CC7-0665884D2094.jpeg

*

[Volo]

A small issue that is not understood by many is which way is up (or down) on a gas strut
The piston rod must be at the lowest point as the oil in the cylinder needs to keep the seal lubricated to retain the gas pressure.
I contacted Gabriel when we had gas struts collapsing every 6 months on a mining project. The engineer was very helpful in explaining the reason.

...............................

On balance I would say that one is installed the wrong way round as in the normally closed position the Rod is up allowing fluid to drain away from the seal .

[Chris71]

A small issue that is not understood by many is which way is up (or down) on a gas strut
The piston rod must be at the lowest point as the oil in the cylinder needs to keep the seal lubricated to retain the gas pressure.
I contacted Gabriel when we had gas struts collapsing every 6 months on a mining project. The engineer was very helpful in explaining the reason.

...............................

On balance I would say that one is installed the wrong way round as in the normally closed position the Rod is up allowing fluid to drain away from the seal .

Nope, I think you'll find that one is indeed installed correctly. The seal referred to would be the one on the end of the rod (plunger section not the housing section) so when access panel is open as per picture the seal is lying in fluid and when the access panel is closed the whole strut assembly has rotated through almost 180 degrees and the rod has gone the the lower end of the housing where again, it will be lying in fluid.

[Volo]

A small issue that is not understood by many is which way is up (or down) on a gas strut
The piston rod must be at the lowest point as the oil in the cylinder needs to keep the seal lubricated to retain the gas pressure.
I contacted Gabriel when we had gas struts collapsing every 6 months on a mining project. The engineer was very helpful in explaining the reason.

...............................

On balance I would say that one is installed the wrong way round as in the normally closed position the Rod is up allowing fluid to drain away from the seal .

Nope, I think you'll find that one is indeed installed correctly. The seal referred to would be the one on the end of the rod (plunger section not the housing section) so when access panel is open as per picture the seal is lying in fluid and when the access panel is closed the whole strut assembly has rotated through almost 180 degrees and the rod has gone the the lower end of the housing where again, it will be lying in fluid.

........
Sorry disagree .
As that unit is installed the rod end will be at the top when the door is closed. It should be at the bottom so that the seal is immersed in fluid when the door is closed as it will be closed 99% of its life.

[Volo]

It only rotates just over 90 degrees. From open to closed not 180 degrees

[Ugly Duckling]

Look here
https://www.gabriel.co.za/gaslift-technical-info

[Volo]

That's what I have said - rod end down

[Chris71]

The seal is fitted on the piston side of the rod i.e the part of the rod furthest from the point where the rod is attached to the airframe. So looking at that picture with the panel in the open position the piston and seal are currently at the bottom end of the gas tube so the seal is lying in the lubricating oil. When the panel is closed the whole strut assembly will rotate and be lying in an almost vertical position. The rod will be at the top and gas tube underneath. But the piston and seal have travelled right into the tube so are sitting at the bottom of the tube, immersed in oil.

[Ugly Duckling]

It's not the seal on the piston which needs to be kept wet but the cylinder to piston rod which is important

[Chris71]

If it is the seal at the bottom of the cylinder and not on the rod that you are referring to then I'm afraid I must eat humble pie and apologize. You are indeed correct Volo. Now who's going to volunteer to tell them it's upside-down?

[Volo]

I bought a Glider trailer 40 years ago and only disposed of it a year ago.
It had two large gas sruts to lift the entire 8 metre roof up
These original struts still function perfectly and as it happens are installed rod end down.

[Chalkie]

Catching a few rays!

Engine ground runs - successful setup and accurately cross checked against ECU/Dynon

SO? Any progress? First flight done? Pilot Report done?

[Little Friend]

Successful First Flight! Smiles all round…

Flies like an absolute dream!!!

[bladerunner]

Successful First Flight! Smiles all round…

Flies like an absolute dream!!!

Brilliant! Looks fantastic!

[Little Friend]

Fantastic!

Can't wait to see her in the air.