Steering on Takeoff
 

Hey Guys/Gals,
Somehow, my suite mate and myself got into talking about takeoffs in transport category jets. He insists that the tiller is used for the first 80 kts on the takeoff roll because there is no rudder steering tied into the nose gear and it's not effective until 80 kts and that's the whole point of the 80 kts callout. Just curious if this is true because it doesn't sound very logical.

That's how it works. On the ATR we do a 70 knot callout for that reason, but I guess on most larger jets it's 80 knots.

The tiller is not normally used once lined up on the runway but it could be low speed. The rudders still move the nosewheel regardless of airspeed. The 80 knot call has nothing to do with tiller use. It's to distinguish the high and low speed abort regime.

He is partially right. Some jets have nosewheel steering tied to both tiller and rudder pedals. Rudders are the first flight controls to become effective during takeoff roll. 80 kts is about the time where rudder deflection is more effective in maintaining runway centerline than nosewheel steering. Tillers are also more dangerous to use at high speeds.

It also serves as a way to x-check ASI with other side

727 sim I was in during college had an 80kt call-out, and but it was, as mentioned above, is a cross-check speed. The rudders do tie into the nose-wheel steering, but it is limited in comparison to what the tiller does(not sure angle in degree's).

My only experience with a nose wheel tiller was on the P-3 Orion, you would have your hand on it at the beginning of the T/O roll until rudder authority was gained, 40-50 kts or so IIRC. On the landing rollout, I think we had a standard of 65 kts or less before you were "allowed" to put your hand back on it. You could pop a nose tire very easy with the tiller.

On the Q400 the pedals have up to 8 degrees of nosewheel stearing so the tiller is not used during takeoff or landing until it is time to make the turnoff or in the case of a high speed you can hold off on the tiller until stopped. But its the CAs plane so he is in the tiller when he feels like it and takes the controls from me.

From what I understand the 80knots reason is for crosschecking the instruments as well as pilot incapacitation...if you say 80kts and they say nothing maybe the bloke is dead and you should consider the brakes.

True as well. There are several good points stated above. My main point was that I've never heard it used as a cutoff for the tiller and don't think it was a valid statement.

I see your point..I did not really notice that, but im with you on that one and do not think that the callout is for coming off the tiller.