double bogey landing gear question
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double bogey landing gear question
Can anyone help me out with the following question? "Which brake and which tyre of a double bogey landing gear get hottest during braking?" How about a triple bogey gear?
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Four wheel bogie landing gear.
I expect the forward tyres would get hotter due to the load transferring to them during braking and the greater deflection caused.
Hottest brake would be the one with most wear since there is less mass in the heat pack to absorb the heat. However on the A300 the brake temps. depend on how well the foot pedal transducers have been set up and can have quite a split in temps.
Hope this helps.
I expect the forward tyres would get hotter due to the load transferring to them during braking and the greater deflection caused.
Hottest brake would be the one with most wear since there is less mass in the heat pack to absorb the heat. However on the A300 the brake temps. depend on how well the foot pedal transducers have been set up and can have quite a split in temps.
Hope this helps.
Joined: Oct 2006
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From: Sydney, Australia
dixi188Four wheel bogie landing gear.
I expect the forward tyres would get hotter due to the load transferring to them during braking and the greater deflection caused.
Possibly. The brake equaliser bars are designed exactly for the purpose of distributing the load in a more equal fashion between the forward and rear axles. If the brakes were mounted rigidly to the axle, the reaction to the braking moment from the front axle brake packs would tend to put a much higher load on the front axle wheels.
The geometry of the equaliser system is such that the brake torque from the individual brake packs tends to lift the front axle off the tarmac whilst forcing the rear axle down harder. This mechanism distributes the load in the landing gear strut in a much more equal fashion between the axles, and makes the rear brakes do their equal share of the retardation duties.
Regards, JetMech
I expect the forward tyres would get hotter due to the load transferring to them during braking and the greater deflection caused.
Possibly. The brake equaliser bars are designed exactly for the purpose of distributing the load in a more equal fashion between the forward and rear axles. If the brakes were mounted rigidly to the axle, the reaction to the braking moment from the front axle brake packs would tend to put a much higher load on the front axle wheels.
The geometry of the equaliser system is such that the brake torque from the individual brake packs tends to lift the front axle off the tarmac whilst forcing the rear axle down harder. This mechanism distributes the load in the landing gear strut in a much more equal fashion between the axles, and makes the rear brakes do their equal share of the retardation duties.
Regards, JetMech
Last edited by JetMech; 26th April 2007 at 07:07. Reason: spelling
