# Knowing when to retract flaps for landing

Just a quick question on landing. Is there a way to calculate a point from which we start retracting flaps? Also, how can I access the flap extending speeds for all aircraft.

Thank you :)

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Tipically you should be ready on 5nm from the Runway. At that distance you should have flaps full, gear down, etc.

It really depends on the aircraft and weight.

For example: if Iām taking off an A350 with 70% load, using flaps 1+F and N1 at 89%, Iāll put flaps 1 when I reach about 200 knots, then flaps 0 near 215 knots.
Normally 200 knots should be reached 1-2 minutes after rotating, although sometimes it takes more time.

Another example: if Iām taking off a 737-800 with 70% load, using flaps 10Ā° and N1 at 89%, Iāll put flaps 5Ā° at about 200 knots, then flaps 1Ā° at 210, and flaps 0 at 220.

But as I said before, it depends on the aircraft, weight, N1 and vertical speed

Retracting flapsā¦on landing?
You mean when you do a touch and go?

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Or do you mean on takeoff?
Because the only time you actively retract flaps for landing is after you exit the runwayā¦

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I mean on descent when your gradually getting slower on the profile, is there a certain point when the first flaps should be retracted.

@FlyingTsunami Iām not quite sure if I understood your question correctly. When youāre approaching an airport you need to extend your flaps with an assigned speed. After you landed safely on the ground you can start clean your spoilers, retract your flaps and so onā¦

(to) retract = making flaps smaller/ away
Example: after landing
(to) extend = making flaps bigger
Example: when reducing speed and approaching an airport

extending thats what i meanāt, sorry for the error

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šš¼ Just make sure to change the title and your topic message so no one gets confused.
Itās actually not that easy to say when to extend which flaps. It depends on the aircraft and the weight of it.

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Sorry, I was just reading the previous responses above mine š (Iām a slow typist)

There are a lot of variables, type of aircraft, weather, etcā¦ but typically after you are below 100-60 kts whilst still on the runway. The primary purpose is of spoilers are to essentially help āstallā the wing in order to prevent the aircraft from bouncing up and thus ultimately helping you maintain control of your aircraft.

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It really depends. Thereās no āsetā method to flap extension on approach and landing per se.
You do it sequentially and not all at once.

The only thing is - you need to make sure youāre slower than a certain speed, when you extend them, those speeds and profiles can be found here : http://www.janpolet.nl/infinite-flight-aircraft-liveries-more/

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Thank you, this really helps! :)

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Oh and especially if you really need to slow down below 250 knots under 10,000 feet, you should definitely use flaps.
It all depends on how you want to manage your speed. Remember, an airliner is fully capable of making no-flap landings. All flaps do is make slowing down for landing easier

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Whilst aircracfts are fully capable of making no-flap landings, itās not really recommended. Speed, flaps, descent angle and trim all make for a good stabilised approach and landing. Wouldnāt you agree @CaptainSooraj? (From one irl pilot to another šš)

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Oh of course. I was just making the point that thereās not a āsetā way to apply flaps, IRL it depends on your companyās SOP usually.

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it all depends on aircraft type, load, descent profile, etc. thereās no set āformulaā to follow for extending flaps, although you should be in full landing config at 5-mile final

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I usually start lowering my flaps at 20nms and am fully configured for landing by 5nms with full flaps and landing gear.

Itās always those darn SOPs, the military is the same way. Which I suppose is a good thing in the end. Standardisation across the board so there is never any question or misinterpretation š¬

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Like when they say 11 kitted-out personnel can fit in my bird, but in reality I can fit far more if I take the seats out.