Military tyres on civil aircraft ?

[aseanaero]

A quick question

I have a bunch of Bae Hawk 100 (jet trainer) MLG tyres (new old stock) which are 6.50x10 14 ply tubeless

Would it be possible (and legal) to use them on something like a Cessna 402C MLG which uses 6.50x10 8 ply tubed ?

The new owner is about to ferry a C402C from Indonesia to Australia (its been parked for a few years), one of the tyres was bald so we did the right thing and imported a new 6.50x10 8 ply and inner tube which has now been installed by an engineer on the aircraft , however there is always a week delay getting things into Indo from overseas and the thought was would these military tyres be ok as an alternative even if just for a ferry flight or getting an aircraft out of an AOG situation ?

I'm a pilot not an engineer and the local engineers give you a blank look when you ask questions like this (I asked)

[Engineer_aus]

Its a Stronger tyre, so why not, however you would best to contact the manufacture to see what the specs that are required. Would be the best way. Personally for a ferry or to get you out of the **** I would install it.

[midlifecrisis]

As above. In order to maintain airworthiness you should strictly contact the airframe manufacturer and get their approval to use alternative components. I too can't see it being a problem .... but I'm not the design authority!!

[aseanaero]

What about the tubed and tubeless difference between the 2 tyres , would an original Cessna rim be compatible with a tubeless tyre ?

When you look at a 8 ply GA tyre and then a military tyre you wonder how long a light aircraft like a 402C would take to wear out a 14 ply tyre , if you can improve safety margins and reduce operating cost why not ?

I think you are both correct however for commercial / liability reasons I cant see either the tyre or airframe manufaturer giving the OK

We did the correct thing and put a standard tyre back on but the question has been bugging me and the owner as we both aren't engineers (or aviation lawyers)

ps. if we were cowboys the tyre would already be on the aircraft

[helofixer]

I doubt it would work correctly, and certainly would not be legal.

Tubeless tires usually use a two piece rim that has an o ring to seal the two halves and the filler port for air/nitrogen for the tire is usually part of/screwed into the outer wheel half of the tubeless rim.

If you tried to use a tube and wheel halves made for a tubed tire with a tubeless thicker ply tire, it might work, but I have my doubts. The bead seating area of the two different wheel assys, tires bead thicknesses and different depths of the two wheel halves might not allow a the tube to expand enough to get the tire to mount correctly on the wheel assy.

Of course if you somehow got the lash up to work, hold air and maybe pass a couple of taxi and braking tests and be facing an extreme emergency/life or death one time no other option available situation, give it a go, if you are so inclined. If you are able to wait for the right tires, do so. Peace of mind is much better than little aircraft pieces.

[Rigga]

If the tyres are on a two-wheel bogie the new tyres MAY touch if subjected to deformation during landings - this should be checked before flying.

[mini]

Putting a tube on a tubeless rim can be dangerous, the rim may have areas that chafe the tube leading to deflation.

14 ply instead of 8 ply shouldn't be a problem, but I would cover my butt & send a fax...:ok: