767 Wheels

[M25USER]

DOES ANYONE KNOW WHY 767 MAIN GEAR WHEELS TILT FORWARD

[ptbodale]

I can ask the maintenance guys this afternoon. I start at 2 pm eastern.

[ptbodale]

There are tilt sensors in the gear to tilt the gear and thus the wheels forward so the aft wheels hit the runway first. Same system as in the B747's. The DC10's did not have this feature because of the higher nose attitude on landing.

[Dmmoore]

DOES ANYONE KNOW WHY 767 MAIN GEAR WHEELS TILT FORWARD

Its very simple. The wheel well was designed to take up the minimum quantity of space possible. That's the way the wheels fit into the well when retracting the gear. That's why the gear requires tilt sensors. If the gear isn't tilted correctly it will not retract because it will not fit into the wheel well.

[Cam]

Are the wheels the axles free flowing or is there a motor or some mechanism to make them hang back?

Was there a reason for the CAPS?

[ptbodale]

Are the wheels the axles free flowing or is there a motor or some mechanism to make them hang back?

I don't have time right now to get the MEL manuals out, I'll look soon)

[Dmmoore]

Are the wheels the axles free flowing or is there a motor or some mechanism to make them hang back?

Was there a reason for the CAPS?

The tilt actuators are hydraulic cylinders. They are set to position the landing gear beam properly.

The wheels are mounted on axles. The axles are mounted on the landing gear beam. The beam is mounted on the landing gear strut. The strut is attached to the wing. The tilt actuator is attached at one end to the beam, the other to the strut. Hydraulic pressure centers the actuator at mid stroke. The center location is the properly lilted position. In addition, the actuator acts as a dampener keeping an out of balance tire / wheel from shaking the beam during gear operation.

[3WE]

Are the wheels the axles free flowing or is there a motor or some mechanism to make them hang back?

Was there a reason for the CAPS?

I'd guess the caps indicate frustration that the gear is COUNTER to what layfolks (such as myself) think the way it should be (tilting up).

The "lever action" of them tilting forward has a little more tendency to jam....when the wheels first touch, they are thrust forward slightly...i.e. jammed more.....if the rear axle touchs first, the tires back away from the forward direction ever so slightly....

That being said, I trust the dudes who decided to go against what seems logical to a layman.

[screaming_emu]

There are tilt sensors in the gear to tilt the gear and thus the wheels forward so the aft wheels hit the runway first.

Huh? That doesn't make sense. If you wanted the aft wheels to hit first wouldn't you tilt them the other way like the 757 or 777?

[AJ]

It's one of the many factors that make the Boeing 767 an easy and joyful aeroplane to land time after time...............NOT!

[767 Driver]

Its very simple. The wheel well was designed to take up the minimum quantity of space possible. That's the way the wheels fit into the well when retracting the gear. That's why the gear requires tilt sensors. If the gear isn't tilted correctly it will not retract because it will not fit into the wheel well.

Tilt sensing is also used for auto speedbrake deployment. If you lose tilt sensing, you don't have auto speedbrakes. According to my manual, if the gear fails to tilt after liftoff, the gear can still be retracted and the proper tilt angle will be achieved by the shape of the gear well.

[MaxPower]

Tilt sensing is also used for autospeed brake deployment. If you lose tilt sensing, you don't have autospeed brakes. According to my manual, if the gear fails to tilt after liftoff, the gear can still be retracted and the proper tilt angle will be achieved by the shape of the gear well.

Really..? I assumed the wheels would hit the sides or the edges of the wells if the crew still tried to retract the gears even if the gears failed to tilt.

But if you say so, we believe you.

[767 Driver]

Really..? I assumed the wheels would hit the sides or the edges of the wells if the crew still tried to retract the gears even if the gears failed to tilt.

But if you say so, we believe you.

Our aircraft manual says that if the gear fails to tilt, the shape of the gear well will force it to tilt in order to fit.

I don't know of any EICAS message that would tell us that the tilt has failed. The only thing that comes to mind is a C hyd system failure, in which case you definately lose tilt and you wouldn't be able to retract the gear anyway.