View Full Version : questions about B737-800

20th Apr 2004, 15:08
Hi all,

Got these following questions from Air China's B738 refresh training courses,any replies will be appreciated.

1 Is it correct to select Auto Brake 3 for landing after a wheel
well fire(assume extinguished)?why?
2 What GPWS warning shall we expect when the airplane
descends through 2000ft radio altitude at an excessive rate
of descent?
3 Respectively with FAA and ICAO rules,how much protection
area(which ensures adequate obstacle clearance)can we have
when shooting a circle to land approach?
4 Is it normal to have FEEL DIFF PRESS light illuminated when
both A and B systems fail?
These questions are all translated from Chinese,hope you guys
could understand.

20th Apr 2004, 16:11
2 - "SINK RATE" with a sink rate of approx 4000 FPM and then "WHOOP, WHOOP, PULL UP" if it continues.

4 - The ELEV FEEL DIFF PRESS light indicates a difference of pressure of at least 25%. With both hydraulic systems off, you should not have this light unless there is a problem.

21st Apr 2004, 01:31
Further to 4)
If the FEEL DIFF LIGHT is on with both HYD Systems off i would suspect you do have a major problem;

A)it can also show an activation of the elevator feel shift(EFS) for 30 seconds.

B)blocked/frozen elevator pitot/static tubes and/or probes

C)blocked HYD return filters

D)elevator feel computer failure

E)wiring fault

22nd Apr 2004, 13:41
Question 1) is interesting.

I would not see it as a cause to fail your checkride, but I would prefer to use manual braking after a wheel well fire, as you may need differential braking in case of tyre failures.

Hope to see many replies to this question...

22nd Apr 2004, 14:41
1 my guess: after a wheel well fire there may be some fuse melt,so eflated wheels. Autobrake 3 means increased braking on the wheels,no matter reversers.I'll use autobrake 1 or maybe 2 with full reverser to minimize braking on the wheels. Just a guess,though.

2)SINK RATE ---- TERRAIN----PULL UP in this order (assume gear & flaps up)

3)The visual manouvering area for a circling app is determined by drawing arcs centered on each rwy threshold and joining this arcs by tangent lines.The radius is based on a/c category.( usually 1.5-2NM)
The obstacle clearance in this area is 300'.
(find all these in jeppesen gen,I think)

4) as said by b735 and ddg

Brgds Alex