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B73Cl&NG landing gear on final

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B73Cl&NG landing gear on final

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Old 3rd May 2007, 06:15
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B73Cl&NG landing gear on final

This question adresses pilot flying on B73Cl or NG.
What does your company's SOP say about point on final where the landing gear should be extended?
Usually this point is 1 dot below or when glideslope alive, but it is noisy, isn't it? I offer intercept glideslope with gears up, descend to 1600' AFE, then gears down. When lights become green set Vapp and landing flaps. Approach should be fully stabilized before 500' AFE in VMC , or 1000' AFE in IMC, so what is wrong in my method?
All answers will be appreciated, thanks in advance!
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Old 4th May 2007, 07:14
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We are doing it at 2000 feet RA. Gear down ,wait for all lights green and call flap 15 (to avoid warning horn before lights green). Then flap 25-30 and check. This way,all is complete at around 1200' RA.
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Old 4th May 2007, 08:05
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alex - the only time the 'horn/greens' are an issue is from F10 to F15. The 737 is 'designed' to take F15 from F5 WITH gear selection - with no horn activation.

2000'RA is normally a 'runway not in sight' SOP as rainboe says, and 1500'RA is the 'normal' minimum when visual. With, of course, the caveat that company SOPs apply
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Old 4th May 2007, 09:24
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Hello BOAC,

Flaps 15 is a normal landing configuration. If you do not have 3 green lights the horn will sound and you can not stop it untill you have 3 greens.
Personally I tend to delay the landing gear if I have strong headwinds or a beatiful CAVOK condition. Otherwise I start the configuration between 3000 and 2500 ft AGL , soon after intercepting the G/S in order to make the Landing checklist at a resonable height from the ground.
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Old 4th May 2007, 20:11
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BOAC , as previous poster said, the horn will sound with no way off shutting it off untill you have 3 greens, no matter where the ldg gear lever is. It does make sense,as you may select gear down and afterwards fail to notice one light remaining red.
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Old 4th May 2007, 21:26
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Sim; GS 1/2 scale, gear down and final flap. So it has been on all the different types I've flown.

Then we enter the real world and we fly as clean as possible for as long as possible before we dump the gear and select final flap. We all do it, line pilots, training pilots, chief pilots, etc, because it's the best way to fly. Economy, noise, time, flap wear, ATC, etc.

6 months later we reenter the sim, GS 1/2 scale, gear down and final flap. By the book and well done!

We don't train the way we fly, and we don't fly the way we train. We all know it, and accept it. Weird!
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Old 4th May 2007, 21:56
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For heaven's sake!
Flaps 15 is a normal landing configuration.
- no it isn't!
the horn will sound with no way off shutting it off
- no it won't! How many times have you had one gear red, alex?

If we are talking about a gear lock-down failure, alex, then obviously yes, but in the REAL world, day after day, on-line with F5, "Gear down/F15" works just fine. No waiting, no horn, no drama, no reds. Boeing pilots have done it that way for DECADES.

The horn would sound as the flap passes F10, by which time the gear is down and locked - OK, I'll grant you maybe just a forlorn 'beep' for a micro-second if the hand is VERY fast.
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Old 5th May 2007, 05:39
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BOAC,
FL15 IS as normal Flap setting.
It is just not used in normal operations but there is actually no limitation on its use by mr. Boeing.
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Old 5th May 2007, 07:48
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I may be wrong, but I thought that the warning horn logic (ie when it sounds and can be cancelled) is slightly different between the 3,4,5 and the NG models, something to do with the mystery PSEU.
Also I thought a flap 15 landing was only approved when called for by an abnormal procedure in the QRH (eg single engine)
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Old 5th May 2007, 09:44
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Also I thought a flap 15 landing was only approved when called for by an abnormal procedure in the QRH (eg single engine)
15 is a normal configuration for landing and is limited only to airports where approach climb gradient is a factor
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Old 5th May 2007, 09:47
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Ref. FCOM 15.10.3 & FCTM 6.1

Bye.
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Old 5th May 2007, 10:20
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wait for all lights green and call flap 15 (to avoid warning horn before lights green
There is no Boeing FCTM requirement to wait for gear lights green before extending flaps beyond 5 to 15. If ithe horn does operate it is only for a second because by that time the gear will have locked down. At least the crew know that the gear warning horn works - providing of course the aural warn circuit breaker has not popped or pulled on purpose.
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Old 5th May 2007, 12:59
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The horn works on actual flap position not selected position. Hence when you select the gear down with flap 15 (from flap 5) then the horn will activate as the thrust levers go to idle. At this point you can cancel the horn as the flap position has not exceeded flap 10. Once the flap position exceeds flap 10 then the horn can not be cancelled.

The gear normally goes down in less time than the flaps take to transit from Flap 5 to exceeding flaps 10. Hence, you shouldn't get a horn that can not be cancelled, in normal ops anyhow!

Now if you select gear down/flap 15 from flap 10 then expect to go deaf...

Above is from my experience on 737 classics...So wot BOAC says is right! So don't argue, ok!

(yeah right!) ATB
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Old 5th May 2007, 14:26
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Sorry BOAC, I was thinking about selecting gear dwn/flap 15 from flap 10.
This way you will get the horn sounding , as the flap will be faster than the gear lock.
We often use flap 10 due to 160 kt/4 DME requirement on many of the destinations we fly to.
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Old 5th May 2007, 16:06
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Aha!

Try:
F10/160 gear up
5D, gear down
4.5D, F15
4.2D flap/speed to taste.

Virtually no extra noise/fuel burn
ATC happy
Safety monitoring programme happy
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Old 5th May 2007, 16:39
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BOAC

Ha funny I used this technique during an app only two days ago, worked a treat....
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Old 6th May 2007, 11:45
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.. but we like to cater for all comers of all skill and experience levels ... provided that the discussion is polite and, at least vaguely, related to aviation technical stuff ...
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Old 8th May 2007, 20:53
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Dont be mad with despegue.....he did hie type conversion course with Sky Europe I think.....
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Old 13th May 2007, 10:24
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For BOAC

FLAPS 10 SPEED 160 GEAR UP on 737CL?
That is wrong due to crossover speed.

FLAPS 10 maneuvering speed is 170.
Although the FCTM states "adequate maneuver margin is retained at a speed 20 knts below the recommended speed for all bnk angles up to 30°". This margin is just on the stall speed. It doesnt consider the crossover speed.
Thatīs why Boeing issued 3rd December 1999 an OMB with tables for revise Boeing Recommended Maneuvering speeds. And Boeing states on that OMB "Block speeds changes are required for 737-300/400/500 flaps 5 and flaps 10. For all other flap positions, the crossover speed is below the Block Speed, and a maneuvering airspeed adjustment is not required".

Rgrds
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Old 14th May 2007, 09:31
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Classic with RSEP installed : flap 5 speed 170 ,flap 10 -speed 160.
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