Crabs in my Slip

[Shadrach]

23 minutes ago, Hank said:

Even easier--walk up to your wing tip and put a finger where it touches your leg. Then walk over to the fuselage and see how far it is to the top of the wing. Then compare how thin the wingtip is, and how thick it is by the fuselage. To get the bottom of the wing parallel to the runway, you would need enough aileron to lower the wingtip by the height difference measured on your leg plus the thickness difference. To touch the wingtip, you'd need to go the additional distance of the landing gear leg. I'm pretty sure we'd all run out of rudder before we got that much bank going while trying to land.

How tall are you Hank? My wing tip is above my waist.

[Hank]

51 minutes ago, Shadrach said:

How tall are you Hank? My wing tip is above my waist.

Mine is, too.

So how far below your waist is the wing root? Bank that far to make the top surface level. But the wing also tapers in thickness, it's pretty deep where it joins the fuse, and pretty thin at the tip. So bank further to make the bottom of the wing level. Then bank still further by the gear height before the wing tip can touch.

i don't think this will happen. But what do I know, the strongest crosswind I've had to deal with was gusting into the high 20s, 50° left of the runway, at KRAP. The nice man at the FBO said that's pretty normal for them . . .

Edited February 22, 2016 by Hank

[midlifeflyer]

14 hours ago, Shadrach said:

I assure you, you are imagining it. Given the dihedral and the position of the mains, the bank angle required to drag a wing tip with the gear down would be severe. Next time you jack up your plane, jack up one side only and see how much raise is needed just make the unjacked side level. I think you'll be surprised.

I agree with you. I'm fairly certain one would find that if the wind were strong enough, well  beyond the demonstrated crosswind component, one would be unable to counteract drift and maintain runway alignment long before scraping a wingtip in the wing-low slip. At least in the GA aircraft we fly.

[Shadrach]

On February 20, 2016 at 3:08 PM, midlifeflyer said:

To the point of forward slip vs side slip, I agree with those who described them in terms of the purpose of the maneuver. They are aerodynamically identical. We refer to a forward slip when we refer to a slip used to lose altitude without adding airspeed; we refer to sideslip when we talk about crosswind landings.

Are they the aerodynamically the same? There are certainly very similar. Couldn't it be said the relative wind is aligned with the fuselage in a side slip and at an angle to the fuselage in a forward slip?

[Shadrach]

On February 20, 2016 at 4:08 PM, daver328 said:

My take: The slip method was easier for beginners - and I taught it to beginners flying a 150/152 with new students. The Slip method gives one a chance to see and compartmentalize an aircraft attitude that is unusual and avoided in all other phases of flight. In contrast, the crab and kick out is more advanced, more comfortable for passengers, but could hurt you if you "run out if rudder" doing a full stall landing ... You must be on top of it and immediately execute go-around (right above the runway, no room for error) if that nose doesn't line up. Personally, I crab until flare unless crosswind capabilities are in question, then I slip higher up,and see if I have rudder authority to align the longitudinal axis with the runway. 

Interesting take. I think that slip method requires a bit more attention and activity. Offsetting the nose into the wind to maintain track is not a great challenge, nor is ruddering (kicking) the airplane into runway alignment in the flare. It's actually pretty easy but can side stress the gear if you run out of rudder.  Plus, it just seems vulgar after watching videos of Mr. Hoover slipping from one wheel to the other while maintaining track.

[midlifeflyer]

2 hours ago, Shadrach said:

Are they the aerodynamically the same? There are certainly very similar. Couldn't it be said the relative wind is aligned with the fuselage in a side slip and at an angle to the fuselage in a forward slip?

I guess if one wanted, one could parse them to such a degree that a sideslip with a quartering crosswind is a completely different maneuver than one with a direct crosswind, which is completely different than one with a rear-quartering one. And that a partial deflection forward slip is a different maneuver than a full deflection one. 

But either way you are flying sideways to the relative wind no matter which one you are doing and I don;t see the instructional or piloting value in what I think is (to paraphrase and update an old professor of mine), a Colgate-Crest distinction.

[MyNameIsNobody]

8 hours ago, Shadrach said:

Interesting take. I think that slip method requires a bit more attention and activity. Offsetting the nose into the wind to maintain track is not a great challenge, nor is ruddering (kicking) the airplane into runway alignment in the flare. It's actually pretty easy but can side stress the gear if you run out of rudder.  Plus, it just seems vulgar after watching videos of Mr. Hoover slipping from one wheel to the other while maintaining track.

Whatever.  Simple is not only good it is safe AND effective.  I will freely admit I am "No RA Bob Hoover"...

Vulgar?  Another reason I like the crab.

I don't fly for the challenge.  I fly to safely transport myself, my family, my friends and my pets or a combination of them safely, econonomically and speedily to destinations.

You lost points on this post, but no doubt gain "style points" when you demonstrate your cross-control skills for your adoring fans even if it is the one in the mirror.  Whatever floats your boat.

[midlifeflyer]

There are two top things that makes a slip difficult for new students.

One is the uncomfortable feeling in the butt of sliding sideways.

The other is that we have yelled at them about maintaining coordinated flight for weeks and suddenly want them to fly uncoordinated.