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Main => General Discussion Board. => Topic started by: matta757 on September 09, 2010, 12:19:13 PM

Title: Throttle pressure needed?
Post by: matta757 on September 09, 2010, 12:19:13 PM
Hey guys,

Can anyone give me an approximation as to how much force is required to move the throttles on any Boeing airplane? As you all probably know, I am building a 757/767 so if you have that specific force that would be even better, but I am assuming is probably pretty comparable between the Boeing aircraft. For some reason 6lbs of force rings a bell in my head, is that right? I am trying to get the tension just right, so any help would be great.

Regards,
Matt
Title: Re: Throttle pressure needed?
Post by: AnneCourtois on January 06, 2013, 07:29:06 PM
According to my defunct Canadien Airline B767 manual, it is 9lbs of force to overcome the autothrottle. I have no data about 'off of autothrottle' but 6lbs seems a bit much for my assumpion because that would mean that the autothrottle system would use only 3lbs more than needed to work. The only reason I see it would be that way is that this 3lbs delta is the compliance margin. (Compliance as in robotics. A robot move but if it encounter resistance, it limits the force so not to kill human or animals. When the resistance is not there anymore, it continues onto its destination). The question then becomes, when in autothrottle mode, can one overcome the levers. As an application designer, I would then disconnect the autothrottle when such forces are trying to overcome the autothrottle, giving back the control to the pilot. But I never worked at Boeing. James Price as an actual TQ from a 737-100 and in a recent video on YouTube, displaces the throttle without a 6lbs effort.
Title: Re: Throttle pressure needed?
Post by: KyleH on January 11, 2013, 09:11:52 AM
The autothrottle on a Boeing drives the thrust levers through a clutch. When the pilot manualy moves the thrust lever, the auto throttle will continually try to drive the lever back to the commanded setting but if the pilot holds them, the clutches will slip untill the the lever is released. The autothrottle will not disconnect if you move the levers, you have to push a button to shut it off.

I don't know if you still need the numbers Matt, but I may have them in a sim maintenance manual I have. I'll have a look.
Title: Re: Throttle pressure needed?
Post by: jackpilot on January 11, 2013, 09:45:12 AM
Quote from: AnneCourtois on January 06, 2013, 07:29:06 PM
James Price as an actual TQ from a 737-100 and in a recent video on YouTube, displaces the throttle without a 6lbs effort.

Anne
Have you met James? He propably could move a 1000lbs lever with one finger...lol!
Just jokin :D

Matt: the clutches on my 787 TQ are adjustable from zero to 12lbs.
It allows to dial in whatever force you are comfortable with.
A good feel implies a solid torque, most repro TQs I tried are so easy to move they feel like flimsy toys. Besides you have to adjust the torque when moving BOTH levers with one hand, as 6lbs per lever gives you 12lbs to move altogether.
If your TQ is not motorized (less trouble for an unnecessary gadget in a private sim) the best feel is the one you like!
Jack