question about the B767

[Pink Panther]

Dear All,
I am studying aeronautical engineering. During this study I have to research a case of a B767 losing two hydraulic systems in flight.

The B767 has three independent hydraulic systems. If the Left and center system would fail, the following faults will occur:

AP: inop
stab trim: 1/4 rate
elev feel: spring feel
flaps: use alt flap ext
gear: use alt gear ext
thrust reversers: right only
spoiler capability: reduced
yaw damper: inop
ailerons: left inbd inop
rudder ratio changer: inop
HGM: inop
RAT: inop

Can someone explane the procedures to follow for each item mentioned above. For instance, if the AP and yaw damper are inoperative, is it possible to fly the AC safely? Also how does the manual gear and flap extension work in the 767.

Thank you very much!
Pink Panther

 

[skydiverdriver]

Man, that's a lot of questions. I hope you don't take this the wrong way, but are you asking someone to write down all of this stuff, from a book that they would have to get out of the aircraft, for free? That seems like a lot of work you are asking someone to do for you. Perhaps if you broke it down a bit. Is this for a paper you are writing? Does your instructor mind if you get this kind of help? Good luck to you.

 

[kevdog]

I don't fly the 767, but if you had a hydaulic failure as stated, you would pull out the book and do the procedures listed by the company you are working for. Yaw dampers not working will force you do fly a certain speed and possibly at a lower altitude. If you had this problem, you would declare an emergency, take care of it and probably land at the closest suitable airport. Hope this helps.

 

[Crusty]

Pink:

That's a bunch of questions there boy!

If you lost the left and center Hyd the aircraft flies just fine. YDs are not an issue with the 757/767. You are going to be headed for the nearest suitable airport while you are running your check lists. The Hydro Mechanical Generator (HMG) is not available as you stated but you don't need it as both engines/generators are still functional as well as your APU. Stab trim is available only by the elec trim switch at 1/4 rate as you stated. While the RAT is on the center system it is still available if needed should you loose the right system, as the fluid is received from the standpipe reservoir. The flaps will be extended by the alt flap switch using electric motors. These work fine in both directions, just extremely slow so you would plan a flaps 20 landing in case a go-around was necessary. The alt gear extension also requires electrical power. You can not lower the ldg gear on a 767 without elec. It uses electric motors to release the uplatches and the gear free falls. You will only have spoilers powered by the right system, panels 2,7 and 11. Reserve brakes and steering will get you to the gate so you can catch the van for coctails with the crew.

Hope this helps you.

Crusty