Anyone know why it's called "CLAMP"?

[Guest Totalbeginner]

Does anybody know why, when the ATS on the MD11 is engaged but inhibited it is called "CLAMP" mode? It's seems like a funny term to use when you consider what is actually happening. Is it something to do with the mechanism that prevents the servos from engaging? The word "Clamp" seems to imply that the throttles are gripped or locked and can't be moved, when in fact full manual control is possible.Anyway, just interested.Martin Neep

[tcas_climb]

I guess you could say the same for Boeings when the same thing happens and you see THR HLD....

[Guest Totalbeginner]

>I guess you could say the same for Boeings when the same>thing happens and you see THR HLD....Yeah I guess you're right!Martin

[Guest dodougla]

This may be completely made up, but I remember hearing in the DC-9/MD-80 series, the A/T would enter "CLMP" mode at takeoff and it meant "Computer Lockout Manual Power" but was pronounced "Clamp"...and the name stuck.Again this may be a complete myth, someone correct me if I am completely wrong.Don

[KCA9304]

>Does anybody know why, when the ATS on the MD11 is engaged>but inhibited it is called "CLAMP" mode? It's seems like a>funny term to use when you consider what is actually>happening. Is it something to do with the mechanism that>prevents the servos from engaging? The word "Clamp" seems to>imply that the throttles are gripped or locked and can't be>moved, when in fact full manual control is possible.Martin,Never thought about the word itself this way and where it came from.Just accepted it, as the ATS drive mechanisme indicating the requested thrust was set.Wherever the wording comes from, some things are valid if you regard it as an abbriviation. ( My translation now I think about the word. Don't think its the reason for the word)CLAMP:Calculated Limit, Able Manual Priority orCalculated Limit, Able Maximum PerformanceWith an FMS calculated limit, there is still more power avail by manual control, even passed the overboost limit when required.So don't clamp the idee you can't do anything more on thrust, what you observed already. I'am also just interested where the word comes from.Regards,Harry

[Guest BlueRidgeDx]

I'm pretty sure it's meaning is literal. The Autothrottle servos are physically "clamped", and thus mechanically unable to alter thrust.Regards,Nick