View Full Version : 737 TE Flaps position/stby power

de facto
25th Feb 2011, 09:41
If someone could please explain with references the way to be sure of the Trailing Edge flaps POSITION when extending the flaps during an approach/landing on STBY power only.

The TE flaps indicator is inop and no assymetry protection is provided.

The maneuvering speed (1/5/15....) are shown on the speed tape but these are based on the LEVER position only.

The amber band for the MINIMUM maneuvering speed is getting info from the TE flaps position and from other factors(AOA,LE devices assymetry,,,,) but how can one be sure that the TE flaps are in the correct POSITION apart from checking pitch vs thrust (in the unreliable airspeed section) for example.

Thank you:ok:

25th Feb 2011, 12:14
I don't know about Classics and NG but certainly in the 737-200 there were red lines on the upper surface of the left flaps which could be viewed from the cabin and they were marked in various settings.

On the other hand, it could be argued that to have the rotten luck to not only have a electrical failure requiring flight on standby power - but to simultaneously have a flap failure even though both engine driven hydraulic pumps are working, is to stretch credulity a little too far?

25th Feb 2011, 12:39
Just so I'm clear - you're talking about multiple failures for which there are no MELs.

Well, according to the SYS B fail checklist:

The amber LE FLAPS TRANSIT light will stay illuminated until the flaps approach the flaps 10 position.I suppose you could stop there and use the Flaps 10 QRH landing speeds. Or just keep extending until you're at the end at Flaps 40 and do a normal Flaps 40 landing.

Those are the only two places I can think of where you'd have a good clue of where you'd be.

Oh - Standby POWER, nevermind.

25th Feb 2011, 13:02
Maybe cross check airspeed with pitch attitude using the Performance Inflight - QRH-General General Flight With Unreliable Airspeed/ Turbulent Air Penetration tables?

Not going to be very accurate but maybe worth looking at.

de facto
25th Feb 2011, 14:23
Yes pitch/ thrust for config and weight in qrh advisory info as i posted at the end of my initial post is one idea/solution.
I am more interested in the speed tape/min maneuvering band data.

de facto
1st Mar 2011, 06:34
Could someone please explain to me how the SMYD is processing the PSEU,FSEU,DEU,AOA?
How does it select the highest BIAS?