Student Landings

[FastEddieB]

A couple examples in the video below, re: stall warning horn and airspeed indicator at landing:

And even on those, the stick still had a bit more travel left. Remember, all the way back is a goal.

 

[N3368K]

Slow down and suck the yoke back all the way to make a full stall landing. If you are hitting to flat, you are too fast and not stalled. Go fly a tailwheel with a CFI a couple of hours, not necessarily an endorsement, and learn three point landings and you’ll understand. Then land like your landing a tailwheel.


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[DFH65]

Still wish someone was brave enough to give me a number like 3 - 13/16"

Not sure what bravery has to do with any of this. The problem is you have failed to grasp a simple truth...THERE IS NO NUMBER! It will vary based on a number of factors and beyond that it isn't really all that critical a few inches either way matters not.

 

[flyingron]

If you are hitting to flat, you are too fast and not stalled.

There is no such thing as a "full stall" landing. It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers. Part of the problem with people not being able to land is that they don't understand energy management coupled by erroneous ideas of aerodynamics.

 

[FastEddieB]

There is no such thing as a "full stall" landing. It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers. Part of the problem with people not being able to land is that they don't understand energy management coupled by erroneous ideas of aerodynamics.

Even if you’re technically correct - and I’m not sure you are...

When landing a taildragger, and rolling the tailwheel on first, one is definitely in the area where “any further increase in angle-of-attack causes a decrease in lift”. IOW, the critical angle-of-attack has been exceeded. Lots of folks call that a stall.

If that’s not a “full stall”, so be it. But as the stick moves back the final few inches and the mains drop anyway, it sure “feels” like a full stall*, and as such I think it’s a good descriptor.


*For a student who has just been practicing full stalls in flight, the same behavior - pitch eventually decreasing in spite of stick movement to the rear - that same behavior on landing will be familiar enough that “full stall landing” adequately describes what’s going on. Whether it’s 100% accurate or not.

 

[steingar]

Ugh, you sound like my CFI

There's a good reason for that...

 

[flyingron]

Note that I said "mains." Yes, you can stall a taildragger by dumping it on the tailwheel. There's only one plane where tail-whumping is recommended. Most want a three-point or a (main) wheel landing.

But if you doubt the veracity of my statement, tell me if you can take off from a three point attitude? In many taildraggers not only can you, but it's the stated short field technique. The aircraft is clearly not stalled.

Part of the problem is people confuse "insufficient airspeed to maintain level flight" as a "stall." That's not true.

Landing is all about energy management. The first half of the problem is arriving at the runway without too much or two little energy. Floating, bouncing, etc... are all indications of too much. Too little, and you're going to drop it in.

The second is maintaining the aircraft alignment and attitude at the time the energy runs out (essentially the flare). Yes, you will be pitched up and will often be close to running out of controllability in some planes, but you will not/can not be stalled.

 

[FastEddieB]

Note that I said "mains."

Well, you actually said, “It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers.”

(italics mine)

Taildraggers have mains, too.

And even nosedraggers can be taken to the same point where any further increase in angle-of-attack causes a decrease in lift - and the plane settles on the runway as the stick is snatched the final few inches to the rear. I’ll continue to call that a full stall landing, and I daresay 90%+ of pilots will know exactly what I mean. And communication is, after all, the goal of language!

 

[Capt. Geoffrey Thorpe]

tell me if you can take off from a three point attitude?

Yes.

 

[flyingron]

Well, you actually said, “It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers.”

(italics mine)

Taildraggers have mains, too.

Correct, and I stand by that statement. If the MAINS, i.e., the two big wheels in the front, are on the ground, there's no way you're going to exceed the critical AOA. The tailwheel will hit the ground before that happens. A three-attitude isn't stalled (at least in most tail draggers).

And even nosedraggers can be taken to the same point where any further increase in angle-of-attack causes a decrease in lift - and the plane settles on the runway as the stick is snatched the final few inches to the rear. I’ll continue to call that a full stall landing, and I daresay 90%+ of pilots will know exactly what I mean. And communication is, after all, the goal of language!

And that is not a STALL. You can call it that, but it is incorrect and misleading and lacks the "communication" you claim you are striving for. It is the belief that speed or power or anything other than exceeding the critical AOA causes a stall is one of the biggest danger zones in aviation.

 

[MauleSkinner]

There is no such thing as a "full stall" landing. It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers.

Staggerwings, I believe through the C models, will be above stall AOA when three-point.

 

[N3368K]

Being pedantic doesn’t change anything. Call it a full up elevator landing if that makes you feel better.

I’ve flown damn few taildraggers. and I’ve flown many, that flown at correct speed that once on the ground will return to flight if the stick is moved rearward. I had a Starduster that was clearly not stalled in a three point attitude when it touched down. If you honked back on the stick, it would balloon back up about ten feet and stall. My short gear gear RV-4 isn’t as bad, but will do it as well. I cannot think of any others offhand which do that.

If you are at proper speed, you reach a point where the elevator will not raise the nose any further, yet as speed bleeds off, it will quit flying. Perhaps technically incorrectly called a stall, it is commonly referred to as full stall landings and everyone knows what it means.


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[RoscoeT]

There is no such thing as a "full stall" landing. It's impossible to get any aircraft I am familiar with in a stall AOA with the main gear on the runway, even tail draggers.

??? Your average trike, power off with full flaps will reach a full-stall attitude on landing. Some can hit tail on the runway, most don't, unless you add power. Trikes are actually better suited for landing in a full stall attitude than most taildraggers.

 

[flyingron]

I know for a fact that the 172 and the Navion will both drag the tail skid before they will stall. That's pretty close to the book soft field procedure in the 172.

With the nose way up the drag goes way up and the aircraft loses energy and slows and the lift goes down (and the plane hits), but it never stalls.

 

[RoscoeT]

I know for a fact that the 172 and the Navion will both drag the tail skid before they will stall. That's pretty close to the book soft field procedure in the 172.

With the nose way up the drag goes way up and the aircraft loses energy and slows and the lift goes down (and the plane hits), but it never stalls.

Ok, I've just done many landings in 172s, 150s, and Cherokees and only once drug the tail ring in a 150 when I quickly yanked the yoke back rather than making a smooth progressive pull to full aft just at or a moment before touchdown. Full flaps and idle power of course.

 

[JonH]

Look down the runway in the flare, and treat every landing like a soft field landing were the two pieces of advice that helped me.

As mentioned there is no number. But, you can memorize your pitch attitude when you take off, and look for the same attitude in the flare.

Do some touch-n-goes with your CFI and don't let the nosewheel touch the ground unless you're full stop.

 

[dmspilot]

When landing a taildragger, and rolling the tailwheel on first, one is definitely in the area where “any further increase in angle-of-attack causes a decrease in lift”. IOW, the critical angle-of-attack has been exceeded. Lots of folks call that a stall.

There are a lot of ways to decrease lift without stalling. That is not the definition of a stall. The loss of lift at touchdown is probably due to airspeed loss decreasing lift faster than increasing angle of attack can increase it without jerking the elevator back suddenly. That's not a stall. While I would love to do empirical research to try and prove this, I don't feel like breaking off my tail tiedown ring again.

 

[flyingron]

Yep, there's a reason for all that Minimum Controllable Airspeed instruction prior to trying to teach you to land. If you're having problems, try doing that just above the runway. Run down the runway at ten feet or so at a minimal airspeed but maintaining level flight. Keep yourself centered and aligned with the runway. After you get good at that, all you need to do is close the throttle and then continue to try to hold it off. I agree with DMS. You're blowing off the energy, not really stalling it. Having the stick (yoke) full back isn't a stall.

 

[RoscoeT]

Having the stick (yoke) full back isn't a stall.

You reach a stall when you've reached critical AOA. Just because the wheels are inches from the runway and you don't get to see the eventual nose drop associated with doing a stall at altitude doesn't mean you haven't reached a stall. If you've reached full aft elevator just before the wheels touch, there's not much you can do to increase your AOA any further short of adding power.

 

[flyingron]

You reach a stall when you've reached critical AOA. Just because the wheels are inches from the runway and you don't get to see the eventual nose drop associated with doing a stall at altitude doesn't mean you haven't reached a stall. If you've reached full aft elevator just before the wheels touch, there's not much you can do to increase your AOA any further short of adding power.

Running out of pitch effectiveness is not the definition of a stall. If you're mains are "a couple of inches" off the ground, my contention is it's a geometric impossibility in most planes to be exceed the critical angle.

 

[SloRoam]

A contrary way to look at this: pick any positive angle, lets say 7.5*, and as you’re “flaring”, keep the nose at that constant angle (look down the centerline to “see” this), and keep it at 7.5* while keeping the plane at the same altitude, preferably a few inches off the runway.

If you keep the pitch constant as you slow down, you will naturally end up with the yoke in your lap.

So here’s how:
1) sit in your cockpit on a taxiway and learn the height above the ground by looking down the stripe
2) come into your approach, get to that angle and height agl (plane appropriate), and hold the angle as you pull power
3) you will find you have to keep pulling the yoke back

When you’ve got that down, try changing the approach speed and different transitions to minimize your float, and you should see good landings.

 

[FastEddieB]

That’s good advice.

One caveat: students, and many pilots, will insist on looking straight down the runway. The problem that can arise is that in many planes at some point the nose will come up high enough to block that view. Unless the pilot is trained to look to the side to judge height, they may be literally blind as to the aircraft’s height above the runway at a very critical time. Hence, they may fly the plane onto the runway fast, because they don’t want to block their view. Or may balloon up and not be able to see it at all.

At least in my experience when troubleshooting landings, thanks very often the proximate cause of the difficulties.

 

[Skip Miller]

The #1 cause for not getting nose-high landings is too-high an approach speed.

Get with your CFI and have him work with you on speed control at touchdown. This is by far the difficulty most people with landings. Be on speed every time! <chirp> <chirp>

-Skip

 

[Daz]

If the yoke is all the way back when you touch down, the pitch will take care of itself.

That’s probably the best advice I ever heard when trying to perfect landings. Try to tickle the stall warning each time upon touchdown.

 

[EdFred]

Running out of pitch effectiveness is not the definition of a stall. If you're mains are "a couple of inches" off the ground, my contention is it's a geometric impossibility in most planes to be exceed the critical angle.

And where are the vectors for measuring that critical angle? I bet they aren't the same as when at cruise.

 

[Salty]

Thanks for everyone's comments. I suppose this has answered my real question...which really was: In my "good" landings is the nose-wheel barely high enough as well. Of which the answer like I expected appears to be yes...

Still wish someone was brave enough to give me a number like 3 - 13/16"

It will only be a fixed number if you are going the exact same speed and descent rate every time. And guess what, get good enough to be on the exact speed and descent rate every time and you won't need this answer anymore.

[edited to add descent rate]

 

[flyingron]

And where are the vectors for measuring that critical angle? I bet they aren't the same as when at cruise.

It's real simple. All you need to know is the wing angle and the relative wind. At the landing phase, the relative wind is pretty much parallel to the ground. As pointed out, you can takeoff from a three point attitude in most tail draggres, it's not stalled with the mains on the ground. SImilarly, most tricycle gear are goign to hit the tail before they get enough nose up angle to stall.

This also plays into a related fallacy, that all the lift goes away at the stall. That's not true. In fact the lift vs. angle curve pretty much is symmetric about both sides of the critical angle. The critical angle is just the point where further increase in AOA doesn't generate an increase in lift.

 

[EdFred]

It's real simple. All you need to know is the wing angle and the relative wind. At the landing phase, the relative wind is pretty much parallel to the ground. As pointed out, you can takeoff from a three point attitude in most tail draggres, it's not stalled with the mains on the ground. SImilarly, most tricycle gear are goign to hit the tail before they get enough nose up angle to stall.

This also plays into a related fallacy, that all the lift goes away at the stall. That's not true. In fact the lift vs. angle curve pretty much is symmetric about both sides of the critical angle. The critical angle is just the point where further increase in AOA doesn't generate an increase in lift.

I don't believe the relative wind is parallel to the ground if you really break it down. I think it's going to be coming up from below, not straight down the wing chord considering you are descending. Which is why you can stall it out at that altitude.

 

[flyingron]

You're not (or at least shouldn't) be descending much in the roundout/flare. Probably isn't going to make more than a few degrees difference. You're still going forward much faster than you are descending. And again, we're talking about when the mains are on the ground. You're not descending at all at that point.

 

[EdFred]

You're not (or at least shouldn't) be descending much in the roundout/flare. Probably isn't going to make more than a few degrees difference. You're still going forward much faster than you are descending. And again, we're talking about when the mains are on the ground. You're not descending at all at that point.

unless landing downhill.

But you can stall it out, inches above the ground.
"I'll take 182 nosewheel drop for 400 Alex"

 

[flyingron]

IT's still parallel to the ground.

 

[Deelee]

Have been having similar issues recently. I had done a (self-admitted) pretty good job landing the aircraft on centerline, stall horn blaring as mains touch.... then I started a.) flying more XCs where I wasn't practicing landings, doing touch-and-goes and b.) started IR training where, again, wasn't practicing landing much. I think I had lost some of the touch and technique that comes during training when you are flying the pattern a lot and just focusing on your airspeeds and landings. To make matters worse, I am now transitioning to a low wing that we bought (haha let the comments fly!) and the sight picture is completely different.

So what I did with my day off on Monday was to rent the 172 and fly the pattern for an hour. All I focused on was airspeeds in the pattern, proper transition to landing (roundout) and focusing on moving my eyes from in front of the plane to looking down the runway during the transition. Magic. Just like the old days. I nailed every single one. And I'm not saying that to brag (trust me, I'm low time - no right to brag about my flying). But every landing was smooth and with as little energy as possible. I remembered that I can maintain centerline without looking at the centerline 1' from the prop! Amazing! Looking down the runway makes it so much easier to control the placement of the aircraft over the runway and alignment of the nose with the center. I guess I had forgotten this along the way. And nailing the airspeeds in the pattern is so key. I actually flew the pattern a little slower than usual since it was just me... 100 on downwind and then quickly to 80 abeam the touchdown point (first flaps), turn base and slow to 70 (second notch), turn final and slow it to 65 and then finally to 60 short final.

Anyway... maybe get back to basics. Just fly the pattern. I have hesitated to do this because I thought I'd find it boring and a waste of time. Turns out it was what I needed to do about 30 flight-hours ago!

 

[chemgeek]

...nailing the airspeeds in the pattern is so key.

Winner, winner chicken dinner! I just unearthed my old C172N POH from primary training and I have a note in there from my instructor for 70 mph on final. That's a little over 60 knots, plus or minus. Worked like magic. Carry more than that and you are fighting to put it down. Flying a C172D during my flight review 2 years ago, the same approach made it possible to land on a downhill grass strip over obstacles, 1200 feet, no problem. Carry the right speed, everything works as it should.