Mr.BA
Topic Author
Posts: 3310
Joined: Sun Sep 24, 2000 12:26 pm

Questions On The B777

Tue Sep 18, 2001 7:00 pm

Hi everyone,

I have some questions on the B777s, wonder if anyone could help me out. My apologies on my ignorance on these.

1) What flaps settings are usually or always set on the B777 for take off? I am not too sure (is it flaps 5)? And in what circumstances the flaps settings would be changed?

2) I heard the main landing gears can turn left/right of a +8 and -8 degrees on the B777-300 to help cope with sharp turns during taxi, is it true and does the B777-200 has this feature?

3) How many feet per minute (Vspeed I suppose?) does the B777 normally climbs to it's cruising height and descending from cruise?

4) I understand the normal cruise speed for the B777 is Mach.84. When you are behind schedule, does the captain normally goes faster or is it not economical enough to?

5) When approaching or landing in severe crosswind, what is mainly used to manovure the aircraft back on course? Kick the rudder to yaw the aircraft or roll it or both? And, does the captain approach the aircraft himself or engage the autopilot?


Thanks a lot for the time. Any help and comments appreciated.

alvin

Boeing747 万岁!
 
cdfmxtech
Posts: 1319
Joined: Wed Jul 05, 2000 11:37 am

RE: Questions On The B777

Tue Sep 18, 2001 11:07 pm

2) I heard the main landing gears can turn left/right of a +8 and -8 degrees on the B777-300 to help cope with sharp turns during taxi, is it true and does the B777-200 has this feature?
**Yes it is true, and the -200 does have this feature**

5) When approaching or landing in severe crosswind, what is mainly used to manovure the aircraft back on course? Kick the rudder to yaw the aircraft or roll it or both? And, does the captain approach the aircraft himself or engage the autopilot?
**Usually, the flightcrews on most aircraft will let the aircraft fly the early stages of the apporach. Thr rudder is used by the auotpelot during an autopilot approach to put the aircraft on th centerline
 
Guest

RE: Questions On The B777

Wed Sep 19, 2001 5:05 am

1. I believe you are correct. Flap 5 is the most common. Flap 15 and 20 are also used for takeoff which give you slower speed thus slightly shorter required runway.

3. Depending on how heavy the aircraft is during climb. At max weight, the aircraft is designed to climb only at 300 ft/min with climb thrust. Typically it can climb 1500-2500 ft/min -- more if it's light. On descend, that depends on how high you are relative to your destination and how fast you are going. You can do the math pretty quick. When possible, the crew would most likely use the FMS VNAV in descent and since VNAV path is based on idle thrust and not the simple geometric path, the result will be different. At the end it all averages out the same, IMHO. In reality, ATC tells you to fly at certain altitude then stepping down. Depends on how fast ATC wants you to get down, otherwise most pilots would do it at 1500 ft/min or whatever is needed.

4. Long range cruise for the 777 is either .841 or .842 depending on alt and weight. If ATC lets you, you can fly faster to save time at a slight fuel penalty (a couple of percent, roughly which usually is no big deal). The FMS has a neat function called RTA (required time to arrival) that you can set at a waypoint and the aircraft will speed up (up to max speed) or slow down (up to min speed) to get there.

5. In crosswind, rudder into the wind, opposite aileron to keep wings level. Upto each airline policy or without policy, up to pilot. Most would disconnect auto-pilot about 500 feet AGL (or MDA/DH) unless an auto-land is performed.
 
Mr.BA
Topic Author
Posts: 3310
Joined: Sun Sep 24, 2000 12:26 pm

RE: Questions On The B777

Wed Sep 19, 2001 7:10 am

Thanks for the help!

alvin
Boeing747 万岁!

Who is online

Users browsing this forum: No registered users and 6 guests