Incremental Flaps In The Pattern

455 Bravo Uniform

Final Approach
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455 Bravo Uniform
Where did this originate and is it still applicable today (and if so, why)? I'm talking about putting in flaps 10 downwind, 20 base, and 30 final (or some other variation of incremental increases in flap extension from downwind thru final)?

Notwithstanding the need for keeping speed up for traffic, or top of the white arc limits, it seems the stablest approach would occur going to final flap extension as early as practical (abeam). One config change, adjust trim, and hold that speed & descent rate.
 
Where did this originate and is it still applicable today (and if so, why)? I'm talking about putting in flaps 10 downwind, 20 base, and 30 final (or some other variation of incremental increases in flap extension from downwind thru final)?

Notwithstanding the need for keeping speed up for traffic, or top of the white arc limits, it seems the stablest approach would occur going to final flap extension as early as practical (abeam). One config change, adjust trim, and hold that speed & descent rate.
I got no Idea when it started but I'll be willing to bet not a one of us here today was alive when it started. I do it almost all the time. I'm not a slave to any particular number of degrees or point, but unless there is some need for full flaps 'Now,' I do it incrementally. I don't like to rely on power to make the runway so I start with a little and add more as needed. Little more 'comfy' for non pilot passengers to not dump the flaps all at once. I fly little Cessnas, some with all 40 degrees. I'm sure it's not the best way to do it for many other makes/models.

EDIT: I might lose that bet. I dunno when flaps were even invented?
 
Once I stabilize the decent at 90 knots with 10 degrees, I make the turn to base and extend the flaps. The plane slows to 80 with the extra flaps with no trim change. Same for turning final. I stabilize at 70 and flair to 60, then I reduce the power and hear a slight burble of the stall warning horn just before the screech of the mains. EVERY TIME I FLY ALONE.
 
In my Husky, abeam the numbers I pull the power, slow down, put in my flaps, adjust the trim so I am configured to glide on in. But...thats not the only way. No power, partial power, no flaps, partial flaps and combinations thereof. Most trainers can be landed in all these modes. My philosophy is, if the plane can do it, the pilot should be able to do it. Look in the POH for restrictions. Try all the possible configurations.
 
I think it’s more or less a simplified way to structure the approach and help with timing, especially in a more complex airplane. I do it on almost every flight. We’ve all seen how a select group of folks like to over complicate the straight in approach and deter the novice pilot from performing one.
 
Where did this originate and is it still applicable today (and if so, why)? I'm talking about putting in flaps 10 downwind, 20 base, and 30 final (or some other variation of incremental increases in flap extension from downwind thru final)?

Notwithstanding the need for keeping speed up for traffic, or top of the white arc limits, it seems the stablest approach would occur going to final flap extension as early as practical (abeam). One config change, adjust trim, and hold that speed & descent rate.
For VFR approaches to landing, I was taught that what needs to be stabilized is airspeed, and that I should do whatever is necessary with flaps and power to maintain the desired glide path.

In a 172, putting in full flaps abeam would require carrying quite a bit of power, and might require taking some or all of those flaps out in the event of an engine failure.
 
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In a 172, putting in full flaps abeam would require carrying quite a bit of power, and might require taking some or all of those flaps out in the event of an engine failure.

Probably not if you flew a really tight pattern.

I learned, and later taught, the incremental way. I think the idea is to keep configuration changes small.

Cirrus standardized protocol calls for one notch on downwind, then full flaps on base. I came to prefer that over waiting until short final for full flaps - it feels like one less thing to worry about on final. I do it that way now in most planes I fly, but try to keep my base in close enough so I could still make the airport with a power failure.

But Lord knows that’s not the only way to fly a pattern!
 
I do fly a tight pattern.

I was taught the incremental way as well, but I don't follow it slavishly, because one needs to be able to adjust according to the situation and the conditions.
 
10% on downwind. The rest on final once I know I have the field made. Only difference would be for a short approach, and even then, I don't go full flaps until I know have the field made, which can vary with wind conditions. I fly the conditions.
 
I like the idea of PoA re-inventing aeronautics. ;) Although, sometimes “Because that’s how we’ve always done it,” is a good enough reason to continue. This is one of those. Sure, you can land light single GA airplanes several different ways in different configurations, but the end result is always in pursuit of a stabilized approach and safe landing.
 
Da20
- first notch of flaps seems to add lift- if any drag
- second notch adds some drag

Early 35
- no notches - just flip the switch when ready and wait what seems like forever for the drag to come in. (With gear out and flaps down, it drops like a stone)

I just add flaps when the runway is “made” or I’m wanting to “drag it in” for some reason
 
Turn the question around and ask when do you really want to be slowed and configured? Do you need 30 seconds stabilized? More? Less? I'm happy with 20 or 30 seconds and sometimes a lot less. If i need to slip until a few feet above the runway then I'll do just that. No biggie. Windy day? I might do a power off 180. In general I like the structure of using incremental flaps but I'm not married to it.
 
Paint by numbers teaching.
 
Final notch of flaps when runway is assured, is how I was taught.
 
Final notch of flaps when runway is assured, is how I was taught.

Runway assured, throttle out, hand on the flap bar, rounding out, use flaps like a collective, if that makes sense
 
In the 172, I was taught 10° on downwind, 20° on base, and 30° or as required on final.

In the Mooney, i drop Takeoff flaps (15°) on downwind, and per the Owners Manual it's Landing flaps (33°) or as required on final. Which is always "as required," it seems I only need Landing flaps when the wind is calm.

With both, it's throttle to idle when I have the field made, it just happens further out in the Mooney . . . .

Just like throttle and elevator, flaps are just another flight control to keep the plane on the desired flight path. Do what it takes to put the plane where you want it, don't be a passenger going where the plane wants to go, you may not like it there.
 
Flying fairly tight patterns, I try to avoid "stablized" approaches in a 172 when VFR; I more or less go for steadily decreasing airspeed, dumping in a bit on base, maybe, but mostly on final. Stablized seems slow and silly at the low end of the GA fleet, after leaving the low-time phase of your flying.

I do avoid adding flaps in a turn, after a T-41 ate one in a club I flew with. . .
 
Where did this originate and is it still applicable today (and if so, why)? I'm talking about putting in flaps 10 downwind, 20 base, and 30 final (or some other variation of incremental increases in flap extension from downwind thru final)?

Notwithstanding the need for keeping speed up for traffic, or top of the white arc limits, it seems the stablest approach would occur going to final flap extension as early as practical (abeam). One config change, adjust trim, and hold that speed & descent rate.[/QUOTE
Use whatever flap deployment procedure that works best for each pilots style.
 
Flying fairly tight patterns, I try to avoid "stablized" approaches in a 172 when VFR; I more or less go for steadily decreasing airspeed, dumping in a bit on base, maybe, but mostly on final. Stablized seems slow and silly at the low end of the GA fleet, after leaving the low-time phase of your flying.

I do avoid adding flaps in a turn, after a T-41 ate one in a club I flew with. . .
Exactly. A stabilized approach just means I’m stable right before touchdown. Flying B52 type patterns in a small aircraft is dangerous
 
The original Navion flaps only have two positions, UP and DOWN. You don't want them DOWN until you are ready to make a steep approach to the runway. The later Navion design put a center position in the flap control so you could stop the flaps at any position (yes there's also an additional valve in there as well, but that was often there even before the notch got filed in the panel). Still the biggest use of partial flaps in the Navion is on TAKEOFF. Using about half flaps gets you a very high angle of climb. Of course, using full flaps decreases the ground roll to next to nothing but it climbs like a dog after that. If the Navion flaps were operated like the old Cessna 170/172 where you could move them quickly, that would be a great feature, however the Navion has rather slow hydraulic actuators.
 
The original Navion flaps only have two positions, UP and DOWN. You don't want them DOWN until you are ready to make a steep approach to the runway. The later Navion design put a center position in the flap control so you could stop the flaps at any position (yes there's also an additional valve in there as well, but that was often there even before the notch got filed in the panel). Still the biggest use of partial flaps in the Navion is on TAKEOFF. Using about half flaps gets you a very high angle of climb. Of course, using full flaps decreases the ground roll to next to nothing but it climbs like a dog after that. If the Navion flaps were operated like the old Cessna 170/172 where you could move them quickly, that would be a great feature, however the Navion has rather slow hydraulic actuators.

That's what I really like about my infinitely variable flaps. As long as I push the switch, tney will move, untilmthey reach the stops. So I can use literally whatever amount of flaps I want for each landing.
 
You add incrementally so that you can adjust airspeed as needed. Let's things happen a little slower than just dumping 30deg of flaps in. Also let's you adjust and not add more flaps than needed.

Or are we just looking for something to argue about?
 
In a 172, putting in full flaps abeam would require carrying quite a bit of power, and might require taking some or all of those flaps out in the event of an engine failure.

Yeah, if you're a 3 mile wide downwind. Otherwise, the 172s you've flown must be very different from the ones I've flown.
 
Or are we just looking for something to argue about?

Nah, just non-flying weather for me and was something I'd been wondering about for a while and figured I'd ask since I was bored. I need something interesting to read today too, see colonoscopy thread :cryin::frown::frown3::frown2::eek2::blush::(:confused::eek::oops:o_O
 
Or are we just looking for something to argue about?
Probably.

Like Fast Eddie said: things are just smoother if you make smaller incremental changes than one big configuration change.

You can finesse the airplane or you can manhandle it.

I prefer finesse.
 
I do avoid adding flaps in a turn, after a T-41 ate one in a club I flew with. . .

Nothing wrong w/ adding flaps in a turn as long as you're within flap operating range. I'm sure the T41 was an abnormality.

Actually, you'll find adding flaps in a turn will be smoother than S&L I have found, IMO.
 
Wow, most of the aircraft I fly have flaps that max out at 45 degrees. I can't imagine what effect 180 degree flaps have on the airfoil.
He’s talking about speed on his jets, not flaps...
 
Nothing wrong w/ adding flaps in a turn as long as you're within flap operating range. I'm sure the T41 was an abnormality.
There have been a few cases of crashes involving asymmetrical flap deployment in 172s. Most folks who avoid flaps in a turn cite those.

I can’t think of any other airplanes (other than high wing Cessnas) where asymmetrical flap deployment has been huge concern. Maybe someone can cite other cases?
 
There have been a few cases of crashes involving asymmetrical flap deployment in 172s. Most folks who avoid flaps in a turn cite those.

I can’t think of any other airplanes (other than high wing Cessnas) where asymmetrical flap deployment has been huge concern. Maybe someone can cite other cases?

Yeah, I had it happen in a EMB-120 Brasilia flying into DFW one night. FO was flying, and she said it was a handful but did a good job getting us down and landed. I know some Capts will think, well, you should have taken the controls, but I asked her if she was OK with it and she was. Flap system on the Brasilia was ridiculous IMO.
 
In my mooney I prefer to put the flaps in on downwind and fly a close pattern. Even so, I do one pump and a time and retrim before the next. And the amount of flaps depends on the situation. Sometimes I put another one in on final if needed.

In the c162, I put them down in stages in downwind, base, and final, as each change is more of a difference than it is in the mooney. In the mooney you'd hardly notice if it weren't for the pitch change.
 
Yeah, if you're a 3 mile wide downwind. Otherwise, the 172s you've flown must be very different from the ones I've flown.
Based on terrain features scaled from Google Maps satellite view at my home field, I fly downwind about 0.7 mile from the center line. In the event of an engine failure, whether I could make the runway with full flaps would likely depend on where in the pattern the failure occurred, the pattern altitude at the airport involved, and whether the particular 172 had 30 or 40 degrees as its full flaps setting.
 
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Nothing wrong w/ adding flaps in a turn as long as you're within flap operating range. I'm sure the T41 was an abnormality.

Actually, you'll find adding flaps in a turn will be smoother than S&L I have found, IMO.
An instructor recently pointed out to me that if a split flap condition occurred, discovering it in a turn would be a bad thing. Made sense to me.
 
Probably not if you flew a really tight pattern.

I learned, and later taught, the incremental way. I think the idea is to keep configuration changes small.

Cirrus standardized protocol calls for one notch on downwind, then full flaps on base. I came to prefer that over waiting until short final for full flaps - it feels like one less thing to worry about on final. I do it that way now in most planes I fly, but try to keep my base in close enough so I could still make the airport with a power failure.

But Lord knows that’s not the only way to fly a pattern!

I like this and am going to try it next time I fly.
 
An instructor recently pointed out to me that if a split flap condition occurred, discovering it in a turn would be a bad thing. Made sense to me.

No worries. Been flying since 74 and have to yet to experience that in GA flying. If it were to happen in a turn you could roll level quickly. But I understand your concerns.
 
An instructor recently pointed out to me that if a split flap condition occurred, discovering it in a turn would be a bad thing. Made sense to me.

I’m an instructor and prefer to make configuration changes with wing level. I like my students do so as well.

A given pilot is unlikely to suffer such a failure even over a long career. So it’s not a big deal. But it can and does happen, and it’s just so easy to plan ahead just a tiny bit and wait until not turning to deploy flaps.

But this discussion has come up before, and invariably becomes contentious. So I’ll rest my case here.
 
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