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As I understand the procedure for go-around it includes retracting the flaps.

Why is this?

The decision to make a go-around must sometimes be made quickly, under stressful conditions, like in bad weather. Retracting flaps introduces one more thing to do under sometimes stressful conditions.

Speed is low during landing and by retracting flaps you give away safety margin for lift. (Speed may also slow further since the nose is raised during go-around.)

Retracting flaps may also affect pitch and thereby make control of the aircraft slightly more difficult in a situation which may already be stressful.

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may be it is to reduce the drag? – user2927392 Mar 30 at 9:50
    
I would think that drag is less important to consider in that situation, compared to the risks I describe in the question. / But I am a glider pilot, we do not make go-arounds, so I don't know. – ycc_swe Mar 30 at 9:55
    
Related but with somewhat opposing answers – TomMcW Mar 30 at 18:39
    
@TomMcW The other answers aren't really opposing. They just say you shouldn't adjust configuration immediately when the go-around is called, which is still true. Wait for terrain clearance first, then start fiddling with configuration (making sure you have enough airspeed for each adjustment before you make it.) – reirab Mar 30 at 22:53
    
@reirab I see, the other question is more about the timing of config changes. Makes sense. Retract to soon you risk a stall. Retract too late you might not climb quick enough. Sounds like it might be a little tricky if you have tall trees ahead – TomMcW Mar 30 at 23:03

For the same reason that you don't takeoff with full flaps. Because the climb performance sucks.

Flaps do add lift, but also a lot of drag. A low flap setting often provides more lift than drag, assisting climbout, whereas full flap offers a whole lot of drag, which is desirable when you want to be slow for landing.

But a go-around necessitates gaining height quickly, which will not work with landing flap selected. The usual procedure, at least in light aircraft, is to wait until the vertical speed is neutral or positive before retracting flap. This minimises some of the risks you've raised about aircraft control.

It is often said that a go-around is a period of heavy workload, and managing the flaps and airspeed is not easy. That is why the go-around is a fundamental procedure taught right from the very beginning, and practiced and tested regularly.

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Pretty much - I suspect most students have attempted a go around with full flaps. The twice I've done it my immediate thoughts have been "Why the hell aren't we climbing?" – Dan Mar 30 at 11:40
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its also very important to retract landing flaps in a missed approach – rbp Mar 30 at 13:20
    
What Ben said. Also, when adding full power on a go-around, some planes pitch nose up or down with full flaps. – MonkeyWrench Mar 30 at 19:16
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I was once doing a soft field takeoff and inadvertently fully extended the flaps rather than fully retracting them. I popped up 50 feet in the air and then suddenly found myself slowly descending, unable to climb, and on the verge of a stall. – David Schwartz Mar 31 at 7:11
    
"Because the climb performance sucks." Straight to the answer. I like your style. – acpilot Jul 14 at 2:46

You correctly point out some of the challenges surrounding the procedure of retracting flaps upon go-around. Go arounds can be a stressful situation, flaps do give additional lift and margin against a stall, and retracting them does result in a pitch change for which the pilot must compensate. Allow me to address each of these concerns in turn.

  1. A go-around can be a stressful situation—especially, as you point out, if additional concerns such as weather come into play. Outside of the training environment, a go around is usually executed because some aspect of the landing is not right, whether that be the pilot, the airplane, the weather, the runway, other traffic, or any combination of those or numerous other conditions. All of these can add up to create a very demanding situation indeed. For this reason, the go-around procedure is carefully taught and practiced often in primary training, and pilots continue to practice and demonstrate it throughout their career. Now, raising the flaps is a normal configuration change that experienced pilots are used to making. Even in demanding situations, raising the flaps should not make an excessive demand on the pilot's attention. This includes already demanding situations such as during a go-around.

  2. Airspeed is a major consideration during go-around. Flaps do give additional margin above the stall, some designs more than others. A go-around is all about transitioning from the low-speed approach to the generally higher speed climb out. Thus, the aircraft will be accelerated, typically to the best rate of climb speed (Vy). Typical go-around procedure will call for retracting the flaps once the aircraft is stabilized with sufficient speed, thus reducing—if not eliminating—the risk associated with reduced margin above stall. Even then, the flaps should typically be retracted slowly and in stages, allowing for the speed to increase appropriately. Putting all this together, proper flap retraction during a go-around will not result in excessive risk exposure due to airspeed consideration.

  3. Retracting the flaps does result in a pitch change, though different types of flap designs will result in different amounts of change at different rates. Again, the pilot should be experienced and practiced in compensating for this change. Again, since the flaps will typically be retracted slowly and/or in stages, the pilot will be able to compensate throughout the retraction process. During the go-around, the pilot is already making numerous pitch changes and compensations as power, airspeed, and lift change; compensating for flap induced pitch change is part of the expected process.

Now, your question was why should we retract the flaps during a go-around. I have addressed your valid concerns above. Now allow me to give a some reasons why retracting the flaps is advisable or necessary.

  1. Flaps reduce climb rate. Flaps add drag which is a good thing for landing, but not good for the climb. In retracting the flaps, the aircraft is configured for its best possible climb performance. Some aircraft have such limited performance that they simply will not climb with full flaps, even at typical elevations and in typical weather. At high elevations and in hot weather, most aircraft will have substantially diminished ability to climb with full flaps.

  2. Each type of aircraft has a speed limit for how fast the aircraft is allowed to go with flaps extended (Vfe). This is for structural considerations so that the flaps and wings are not damaged by excessive speed. Retracting the flaps allows for acceleration to climb speed and above without the risk of overspeed damage to the flaps. It is very possible, in some aircraft, to overspeed the flaps after the go-around if they are not retracted soon enough.

  3. For multi-engine aircraft, having the flaps retracted typically puts the aircraft in the best configuration to handle an engine failure emergency. If one of the engines fail, the aircraft will climb best on the power of the remaining engine(s) with the flaps retracted.

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Retracting flaps on a go around is not done until a positive climb rate is attained. And even then it should be done incrementally as airspeed picks up. The specific checklist varies among planes, but generally speaking you throttle up, remove carb heat, attain a positive climb rate, (raise landing gear if it is retractable), remove one click of flaps, wait for speed to increase, remove more flaps, wait for speed increase, rinse and repeat...

A go around isn't unlike a takeoff, you want to be climbing as fast as possible, shedding the drag caused by the flaps allows you to pick up speed faster, resulting in a safer climb. But, you can't just fully retract the flaps immediately because they are providing significant lift, you could slam into the ground if you aren't climbing or if you reduce flaps too quickly. There is also the danger of stalling if you reduce flaps before your speed has picked up sufficiently.

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Flap retraction is not always accomplished after positive rate. Some situations, such as wheels already on the ground, may call for initial retraction with no climb rate. This will depend on the situation, the aircraft, and pilot judgement. – Jonathan Walters Mar 30 at 11:12

Since the first objective of any go-around is to establish a stable climb-out, the procedures involved all revolve around changing the current configuration to the required climb-out configuration. Stuff like power-up is pretty obvious in powered aircraft, and since most aircraft use far more flaps for landing configuration then take off, selecting take-off flaps also begins to seem more obvious.

The original question is based on an incomplete understanding about how flaps work, which some of the other answers here have not helped clarify. Most people know that flaps affect lift, drag and attitude, but tend to forget that each is affected by airspeed at different rates. In particular, drag increases far faster then lift when airspeed increases and this is why most aircraft use far more flaps for landing then for take-off. Also people tend to often forget that flaps are used during take-off to reduce the runway requirements, not to increase climb rate, and in a go-around, you are not on the runway so it is not a factor.

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First of all, if you fly faster than a stipulated speed with flaps deployed it can damage the flaps, so just in the interest of getting the airspeed up alone, you usually need to retract the flaps as soon as possible.

Flaps are kind of like brakes, they slow the plane down. Not a good thing when you are trying to get to altitude.

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Flaps change the wing properties and thereby changes the lift, the approach attitude and lowers the stall speed (all landings are basically controlled stalls). If you need to get out of trouble quickly in a go-around then you may need all the energy that you can get, retracting the flaps changes the wing back to the efficiency of take off to allow you to climb out of trouble.

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Flaps add lift and drag. This answer is misleading. – Greg Taylor Mar 30 at 10:41
    
I accept. Do you suggest I delete ? – AndyW Mar 30 at 11:00
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Usually you want to edit to fix any issues with a post that are raised in the comments. If the issues aren't fixable without completely overhauling the post, sometimes deleting and possibly starting over is the better thing to do, especially if the issues are serious (saves you from the risk of receiving further downvotes while you are fixing the post). Note that having a large number of downvoted and/or deleted posts may restrict your ability to post further. You can delete, edit and then undelete if you want to. – Michael Kjörling Mar 30 at 11:10

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