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View Full Version : any different Approach Speed vs Command Speed ??


in FACT is
7th Jun 2010, 07:26
Dear Instructors & Examiner,

I'm just refer to B737NG FCTM page 1.13 regarding Landing Speed, it says :

"The minimum command speed setting with autothrottle disconnected if Vref+5knots, The gust correction should be maintained to touchdown while the steady headwind correction should be bled off as the airplane approaches touchdown"

Does it mean, you set the command speed to Vref+5 kts if you plan to land with autothrottle disconnected, and if you have gust correction you set the command speed to Vref+gust correction because you will touchdown with this speed, but if you don't have gust correction only headwind correction, you may set command speed at Vref+5 kts and fly the approach speed which is higher than Vreft+5 kts, and bled off this approach speed to Vref+5 kts as the airplane approaches touchdown.

Anyone have better knowledge please welcome to PM me or inform me as I need this clearify badly:} I don't mind if my understanding is wrong:ugh: but I need the information.

Thank you so much, and Happy flight:cool:

Vortex Thing
20th Jun 2010, 00:52
in FACT on the nail old chap. Now one seems to be helping so I'll bite I'm a B737 pilot.

Exactly as you put it. If you are landing autothrottle OFF or speed deselected i.e in ARM then in the case where there is no gust additive component to the fly Vapp to the threshold and bleed off the speed to Vref+5 in the flare from 27ft.

I wouldn't assume the additive is also positive. In some of the IGW versions of the 700 and the SFP versions of the 800 I think you may find that they have an increased FCOM/AFM limit allowing you to accept up to a 15kts tailwind on touchdown. So be careful with the calculation especially if FACT is indeed your location as airports in this continent don't like to change runways unless they absolutely have to. I recently heard an Arik B737 at ABV complaining about the 25kts TW they had on final to 22 @ ABV to be told it was ok as another B737 had just landed :ugh:

Tee Emm
20th Jun 2010, 12:12
Now one seems to be helping so I'll bite I'm a B737 pilot.

The chappie that started this thread (FACT is?) posted his question on two forums at the same time on 7 June. One in Tech Log and one in this forum on instructors. Don't waste your time replying to him on this forum (Instructors) as the subject was discussed comprehensively in Tech Log.

Tee Emm
20th Jun 2010, 12:14
Vapp to the threshold and bleed off the speed to Vref+5 in the flare from 27ft.

Not so. Read the post by Centaurus Item 12 on the above subject in Tech Log.