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I keep hearing from countless instructors, and even some DPE's, that in single engine aircraft, no configuration changes are allowed below 200AGL (i.e. flaps).

Some have also stated that this is when a single engine is supposed to be stabilized, despite the 500/1000AGL rule for VMC/IMC approaches respectively.

What's confusing is this is used from instrument approaches to power-off 180's, yet I've heard people use the last notch of flaps to "bump" them to their point.

Does anyone have a source on this 200' rule? Any help is appreciated!

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  • $\begingroup$ I've never heard of a rule like that, nor would it make any sense. You put gear up before 200ft, and you may raise or lower flaps below that for very good reasons. $\endgroup$
    – GdD
    Commented Oct 11, 2018 at 20:35
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    $\begingroup$ Agree with @GdD, I can't imagine where this idea would have come from. When taking off the gear normally is raised as soon as landing back on the runway ahead is no longer an option - often well before 200 agl. There are good reasons to have a stabilized approach, but an edict restricting all configuration changes to above 200 agl would not work on every occasion. $\endgroup$
    – user22445
    Commented Oct 11, 2018 at 21:10
  • $\begingroup$ Another thing to point out is that the 500/1000AGL thing is not a rule, it's just a guideline. It's a good guideline for sure, but it's not in the book. $\endgroup$
    – GdD
    Commented Oct 11, 2018 at 21:21

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There is no rule. There is a convention that you should be in a stabilized condition that requires no major control inputs or power changes in the last few hundred feet. With jets, airlines often have an operational policy that requires a stabilized approach configuration once below 1000 ft to continue with a landing.

The reason is pretty simple. If I'm well outside a descent rate or speed parameter close to the ground, I'm forced to attempt a much more radical correction, because I don't have much time, than I would farther out. The radical correction will, unless the pilot is very experienced and proficient on type, invariably result in an over correction, and the result is oscillation about the target parameter just as the moment of truth is approaching, and from there things get entertaining.

So in training it's a mantra that is almost universally taught that you need to be settled in on slope and on speed when getting close to the runway. On little airplanes, a couple hundred feet, on bigger ones, maybe 500, on transports, a thousand. The more the mass and inertial involved, the farther out you need to be settled in.

If you are sufficiently skilled and experienced on an airplane type, all this is not quite that critical, but for a newer pilot it's pretty important.

The stuff about using the last bit of flap to stretch a glide doesn't work. It might theoretically help you make it across a ditch before touching down if you were cutting it that close with an engine failure, but more likely it just steepens the glide angle and makes things worse.

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  • $\begingroup$ Indeed, one of the things I learned from my time in ERJ sims (traded seat time during instructor fam sessions for porting their DOS pilot training tracking app to Windows on my free time) was in fact this very valuable lesson -- get in the habit of configuring for a stabilized approach well before you have to worry about anything else during the approach. $\endgroup$ Commented Oct 12, 2018 at 7:48

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