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Old 20th December 2001 | 02:20
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QAVION
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(scanscanscan)

From the Boeing Maintenance Manual (Ch 22-32-00p33)

"When the N1/EPR mode on the MCP is engaged, the thrust levers are driven until the reference N1/EPR is reached. The T/O throttle hold (THR HOLD) mode deactivates the autothrottle servo by removing 115V ac excitation and zeroing the command when the airplane reaches 80kts CAS. This prevents the thrust levers retarding after T/O thrust is set"

Also, according to the Maintenance Manual, RTO must see 85 kts or greater. The simplified block diagram for the Antiskid/Autobrake Control Unit shows "average wheelspeed" rather than IRS for RTO. RTO is completely independent of the IRS's, that's why you can select RTO without the IRS's being aligned <img src="wink.gif" border="0">

Having said this, there are a variety of manufacturers producing these computers. There are some differences between models

Rgds.
Q.