@ forget
I guess you are working on B737.
Originally Posted by AMM B737
Prevent Airplane Movement During Engine Operation At High Power
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- You must set the parking brake.
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- Make sure the ANTISKID switch, on the center instrument panel P2, is in the OFF position.
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- Put the wheel chocks 6 to 12 inches (15 to 30 cm) in front and aft of the nose gear tires and all the main gear tires.
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A320 Fam. AMM do not mention any space between wheel and chocks:
Originally Posted by AMM A320
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If high power is necessary (above 1.20 EPR) aircraft must be immobilized by wheel chocks and brake pedals. Do the following procedure:
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- On the LANDING GEAR CTL & IND PNL 402VU select "A/SKID NOSE WHEEL" switch in ON position.
- Fully depress brake pedals and hold.
- Release parking brake handle
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Normally the parking brake is able to hold the A/C at its position with 1 engine at high power setting. (even by the A320 Fam.)
I prefer the space between wheel and chocks not in conjunction with friction. As i mention above the parking brake is all i need and when she fails during high power you feel a bump when the wheels touch the chocks. It is like a wake up call to retard the throttle(s).
