Wheel change on a 747......

[Lan Ding Gere]

Hi guys & gals,

A question for everyone here and I am sure that some of the engineers from Cardiff may be able to shed some light.

How is a wheel/tyre change taken place on a 85 tonne (not sure of weight) airliner, in this case a Boeing 747.

Is it simply a case of Jacking it up and changing the spare ?

OK Now assuming it was one of the tyres from the main carraige, would this not put the plane off balance by jacking it up. Are there any sites that you know off or any pictures that shows a tyre/wheel change taking place ?

Regards

LDG:D

[BlueEagle]

Engineers will give you the detailed reply but, in my experience, they produce a bloody great jack and change it as you might change your car tyre, full of fuel and pax if necessary!!!

[lomapaseo]

While still wating for the real engineers to comment, I was most impressed one day at JFK while standing underneath a B747 with 16 flats and shredded tyres after aborting above 150 kts.

I thought about how bad my day would be with a single flat in the middle of a motorway, let alone 16 to change.

I was equally impressed with the ease of replacing these tyres simply by cocking each boggie one axel at a time with a fully loaded freighter.. It may have been even easier to change out a tyre on a B747 then other smaller aircraft, but I'll await a real engineer's response.

[Knold]

In my experience it's the same routine with all larger aircrafts, only thing differing is the size / capacity of the jack. (same with the brakes only you have to remove the tire first ;) )

[tinyrice]

Like the man said - stick a bloody great jack under the bogie / leg, jack it up just like a car, and change the offending wheel. Big jets, little jets, all done much the same way - only the jacks get bigger. If you have all of them flat on one bogie, you might need a thing called a Rhino jack, which has an extension arm that can accomodate the reduce bogie clearance in order to jack it up enough to get the wheels off. You can jack a 747 Classic up to its max taxi weight for a wheel change. Remember when you jack the aircraft, you dont need it that much ground clearance, plus there is some compression of the strut , thats why it wont fall over on the ramp and embarrass you.

[What_does_this_button_do?]

340-200 Having a tyre change (http://www.airliners.net/open.file/081103/L/)

[Denzil]

Much as mentioned above its a matter of chocking the aircraft, releasing park brake and jacking up. On some aircraft the wheel can easily be removed/replaced with the brakes off, however some aircraft required a dolly or spider to be fitted to the brake heat pack to line up the rotors and brakes setting to allow fitment of wheel. Obviously then inflate the tyre (nitrogen) and carry out final pressure check with jack released.

Not sure about the DC10 but the centre landing gear oleo will need to be unpressurised to jack up on an A340.

[Lan Ding Gere]

Thanks for the info guys.

Much appreciated

LDG