When to retract the flaps?

Guys if you have a post so you can delete this one.
Yesterday I had a question of when to retract the flaps. For example I take off with Flap 10 and from what I read, they said that when it hit 210 kts it was time to retract. My question is when will I reach this speed, will I retract everything?

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Usually flaps are retracted in stages at or above an FMS derived speed which is the minimum manoeuvring speed for that flap setting.

For example, something like the 737 you’d start to accelerate at 1000 (this altitude is company dependent). If you’ve taken off with flap 5 you select flap 1 as you pass the flap 5 minimum speed then flap up as you pass the flap 1 minimum speed.

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Usually when the fpv on the HUD is starting to lign up with the AOA, but this is not accurate. It’s just my reference on IF. On XP11 there is a speed decided by the FMC, but IF doesn’t really have a working FMC!

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Flaps largely depend on aircraft weight as well.
As mentioned by @Stu flaps are retracted never all in one go, but in stages, as your airspeed increases.

On YouTube you find the official Infinite Flight pilot training videos and there are some takeoff videos for a number of aircrafts. Have a search and check it out.

On the CRJ:

On the DC-10/MD-11

B787

And the big C-130

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In the C130’s, the flaps stay down the whole accent. Other than that, retract right after positive rate and gear.

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I asked just yesterday was with 747-400 the setup was for Flap 10. I tested retract in the 210kts and saw that the aircraft began to descend -2,500 Vs. Arriving home I will calmly read what you have sent. Thank you friends!!

@Murilo_Heindrich perhaps because you didn’t apply positive trim!

i never had an issue with 747 takeoff even at MTOW, i use at least 50% positive trim, also as its been mentioned by other users don’t retract flaps all at once,

for example on a boeing 777 i use flap 5 and 40% positive trim, i retract flap 5 at first and then retract flap 1 as my speed is increasing and i reduce the positive trim while reducing the vertical speed and adding more airspeed,.

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General rule of thumb for GA Aircraft is to retract the flaps at 300AGL, I don’t really know if this applies to the Cessna Citation though.

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I do it so I leave between 35 to 50% + and when it retracts it started to go down.

manually fly the aircraft pull the nose up very gently and slightly to correct the pitch as you retract flaps one after another, and as you get to a comfortable vertical speed engage the autopilot for altitude and vertical speed and you good to go,.

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Cool, that’s what I’m saying … Thank you @MGM1

Thanks to everyone who wrote explaining. I’ll apply and see more of the videos. @Stu @azeeuwnl @MaksimFerguson @Adam_Al-Finge @BadPlane ✌️😀

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You are right, @Murilo_Heindrich
What you are looking for is the Flap / Speed schedule. Every airplane has a diferente one, depending on flap configuration and flap retraction sequence.

In a nut shell, higher flap settings lower the airplane stall speed, and therefore the V2 speed (which is based on a factor from the stall speed), thus the Vr (rotation speed). That is why, usually, on shorted fields you should select a higher flap setting to maximize payload, and when you have a longer runway, you can use lower take off flap settings.

Now, you use the Flap Schedule to determine the minimum speed at which you should initiate the retraction to next flap position. I have attached the Flap Schedule for the B-737 CL -Classic series (-300/-400/-500). As you can see it also depends not he weight (because at higher weights, the stall speed increases). Every aircraft has similar charts.


The “point” at which you initiate the acceleration to reach those speeds is a whole different story. This “point” is usually determined by altitude (however some SIDs have waypoint speed restrictions, which might force a given flap setting in order to comply).The altitude is determined by Noise Abatement procedures, SID climb compliance, Obstacle clearance and/or Company policy.

Regulators usually limit the minimum acceleration altitude to 400 ft AGL, and manufacturers recommend 1,000 ft AGL as standard. However any of the aforementioned (Noise Abatement procedures, SID climb compliance, Obstacle clearance and/or Company policy) can change the altitude for a given airport.

As an example, for a given Noise Abatement Procedure, you continue the initial take off climb with a best angle of climb speed (usually V2 + 10-20 knots) and the original take off flap configuration, and continue the climb until 2,000 ft AGL. Upon reaching the altitude, you reduce the rate of climb (and usually the N1 limit-(power setting) from TOGA to Climb) and start accelerating. As you start reaching the Flap Schedule speeds, then you retract flaps to the corresponding next position.

Well, I know this is very long (in reality this is just a summary, this is a very complex performance topic), but I hope it gives a better understanding of the issue you (and some others) are wondering about.
If you have any other questions, feel free to send a PM.

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I usually retract flaps when I’m above a certain altitude 😂

Very interesting what you sent me. Thanks for sharing @ViperB727✌😀

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@MGM1 Lets ask you … During the cruise do I have to leave 0% trim?

Oh, no? Just ask your friendly neighborhood bush pilot 😏

But I digress…

you might need a bit of positive trim during cruise depends on your aircraft weight, if your aircraft is pitching up during cruise its means you need to apply some positive trim, you will notice a little pink line in the trim box! gently apply positive or negative trim and see if the pink line goes away, for example apply 20% negative trim at first and see! if the pink line got bigger that means you are supposed to apply positive trim and keep applying positive trim until the pink line inside the trim box is gone! you might not feel any differences but this will help your aircraft a lot at cruise altitude,.

but then during descend you will have to reduce the positive trim, lets say it was at 36% during cruise bring it down to 20%,.

for very heavy aircrafts such as the 747 lets say you are doing a long haul flight and you’re very heavy on fuel! you might need to keep 70% or 50% trim at cruise level to help with the pitch,.

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Very cool!!! I’ll try this today !!! Thanks again.😃😃😃😃😃😃😃😀✌️✌️

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