Tips for smooth usage of flaps?

Does anyone have any tips for when to deploy/retract flaps for smoothest operation? When reducing my speed for most aircraft I just have the same routine, flaps 1 around 200, 2 at 180, 3 at 160 and 4 as I slow down to Vapp but I still don’t feel it to be the smoothest to have a one size fits all solution. But it’s hard for me to judge when to actually use them. And often it gets unstable due to the flaps being deployed. Any tips would be great.

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It depends on the aircraft and different circumstances.
There are several guides available on the forum.

Any specific aircraft?

Constantly readjusting trim also helps.

I do readjust trim all the time, I mostly fly A330 or A350 but also 777 but even for Boeing I use the same logic just adjusted for the numbers of angle they use.


Arrival (Configure)

  • Flaps 1 - 240kts
  • Flaps 1F - 215kts
  • Flaps 2 - 196kts
  • Flaps 3 - 186kts
  • Flaps Full - 180kts


Arrival (Configure)

  • Downwind or 12nm out and below 255kts, Flaps 1 - Prior IAF, slow 235kts and Flaps 5
  • 25nm, slow 215kts and Flaps 15

See the QRG for certain aircraft (when available) on this page:

And links to tutorials (when available).

Flap Limits are also available for each aircraft.

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The figures you’ve given are for flap limits, I’m aware of them and always go below those speeds before deploying the respective notch, I’m just wondering for any tips rather than relying solely on my method I mentioned in the post

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If we just had autotrim.😔


Would be super useful for sure


Tbh it would also be great if like real life we had the notches on the PFD telling you when to add and retract flaps

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Most aircraft have a plate somewhere inside the cockpit that specifies the flaps limit for the aircraft.

Yea I know, but this is more about the ideal speed to deploy them since I don’t think you should deploy it right at the limit speed you know?

Unfortunately IF doesn’t have a functional FMC in the aircraft, so either you’d need a third-party app for that, or you just have to wing it.

I remember work was being done on a third-party FMC app.
Don’t know the status though.

Yea… hopefully it could be a feature soon tho

It is very complicated, on many levels.
That’s probably why the third-party project hasn’t delivered anything yet.
But it would be absolutely awesome to have it.

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My ideal speeds are from 200kts (flaps 0) to 160kts (flaps fully extended). On the B737 it goes: 200: 0, 190: 1, 180: 5, 170: 15, 160: 30, and once the ILS becomes active, I slow down to Vapp.

Hope this is what you’re referring to.


That’s basically how I do it, except I don’t really fly any narrow bodies. But that’s basically my exact method. It would just be nice to know for sure when would be a good time because I’m sure it’s varied based on load, wind etc rather than just having a set speed you know?

As far as smoothness of flap usage, I mostly rely on reasoned “seat-of-the-pants assessment”.

The purpose of flaps of course is to generate more lift at lower speeds without having to rely only on increasing AoA (angle of attack).

So, I use AoA to judge flap retractions and additions. I simply remove flaps as the AoA substantially flattens out with speed increase; or add flaps to keep the AoA down to within a reasonably tight range as I slow down. And of course, this change in AoA happens gradually as in response to your changing speed.

On top of this I often note what the speed is when I’m doing the transition and consider if the speed makes sense from other information, I’ve read over time considering the aircraft type (but I don’t obsess about the exact number; mostly it’s a “roughly right” cross check).

But one other cross check I use occasionally, is vertical speed response to pitch control inputs (if you find you’re ballooning too much when trying to descend, that’s obviously a problem).

Wind doesn’t have any effect after you’re clear of the ground.

Flap speeds do change with load. But the AoA method takes this into account.

For higher load at a given airspeed, the AoA will be higher by the amount necessary to generate lift equal to the extra load.

But because you’re trying to keep the AoA from getting too high, that extra load info is “baked” into your judgement to change flaps (causes of high AoA in stable flight: low speed and high load)

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That’s a good method, but what’s the range you recommend to keep AoA? I’m unsure what the numbers should be for it… if that makes sense

It depends on the aircraft type and the load. If I thought I had too much uncertainty about a particular situation I might glance at some of the numbers in some of the guides. But I typically don’t now, just from having flown whatever aircraft type it is for a good while. I might start with some basic speed transition range as you mentioned, and just keep in my mind what the effect of my load will be on top of that.

But then I rely mostly on managing AoA (that’s stable AoA, judged by the nose relative to the FPV; not when you’re making sudden pitch changes, and sharp turns).

So the speed is whatever it needs to be to manage the AoA.

As mentioned, I keep an eye on speed that results, but the AoA is telling me when to change, not the speed. (From what I understand, the first aircraft had AoA indicators, rather than any speed indicator at all.)

edit: so the 1st paragraph above is just for a secondary reference, the AoA is doing all the talking (or almost all anyway).

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