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View Full Version : Crabbing or one wing low, for kitfox, which is best?



rogerh12
03-29-2011, 12:13 PM
Howdy all;
We have a lot of runways around here, and my flight instructor only tought the wing low landing technique. If the cross wind was too high, we just land at another airport. But I understand another methode is to just rudder into the wind and land in a crab, but this is mainly done in very high cross wind conditions, I think. Which is best for the kitfox, or how much cross wind can a, for example model 4, take before the wing low methode should be replaced by crabbing into the wind?

Thanks in advance.
Roger

vetdrem
03-29-2011, 02:05 PM
I NEVER, NEVER, NEVER land in a crab. I don't think that there isa NORMAL crosswind landing, but the way it normally works out for me is that I make sure that I have enough rudder to maintain the nose pointing straight down the runway while staying on the centerline.

I will usually come down final in a crab, staying on the extended centerline until I'm 10 feet or so AGL. At that point, I kick it around so that the nose is lined up with the runway, holding it there with the rudder. With the nose as straight as I can posibily keep it, and the upwind wing low, I touch down on the upwind wheel and hold that wing low attitude as long as needed to stay on the centerline (or as close as I can). When the othere tire decides to come down, it's down.

I don't think that a Kitfox can ever be landed in a crab without tearing off the landing gear, or at least bending something.

ALWAYS keep the nose pointing down the runway as you touch down.

I fly a model 3 taildrager, but I'm sure that it applies to planes with a nose wheel also.

rogerh12
03-29-2011, 02:17 PM
Sorry, let me revise my question a little. I really meant which is better, approach in a crab (and strengthen out just before landing), or fly wing-down all the way to the ground (keeping the nose straight with the rudder), and touch down with 1 wheel. That's my real question.

Slyfox
03-29-2011, 02:18 PM
oh but yes yes yes you can crab. in fact if you crab into the wind, lets say 25mph direct cross, you stand a chance of flying your airplane again. I've landed that way and continued into the taxi way off the runway.

I remember one time I was flying with a cross of 25 and nobody was flying, I was, In fact I was doing touch and goes. there was a group of people watching. I was coming in for the sod and pointing into the wind the whole way, after touchdown I took back off pointing into the wind and turned and went down the runway after take off. With winds like that you can touch down and roll to the other side of the runway and stop no problem. what you do after that is another story.

My thoughts, it all depends on the winds and turbulance if I use the crab or wing low. if the rudder doesn't work any more, than it's a dah! crab time.

vetdrem
03-29-2011, 02:43 PM
Steve, if you are saying that you land diaginally across the runway, I agree. In fact that is a very good way to minimize the effects of a crosswind, but my point is that if you touch down in a crab, putting large side loads on the gear, it won't last long.

Land at an angle to the centerline if you like, but keep nose pointing the direction you are traveling.

Louie

Slyfox
03-29-2011, 03:51 PM
I have crabbed and rotated on landing with no ill affects. Must be the tube gear that has that problem.

land wing down hummm..., have to admit, I mostly land wings level even with a good cross. the only time I land with wing real low is when I want to do a weelie. generally followed by a land on the two and than lift it for the other side. So I guess it is just what feels right at the time, can't say which is best, just land the plane, how about that one.

vetdrem
03-29-2011, 03:57 PM
Must be, but I'll just keep trying to keep the wheels rolling the same direction the plane is going.

Louie

Slyfox
03-29-2011, 04:29 PM
I think the best thing to do is go out and do nothing but touch and go's and try to do it when the winds are blowing, than and only than can you figure what YOU are comfortable with.

I generally do the three point when things get hairy. I shoot for the full stall landing. that's about 3 feet off and let it stall and land, could be wing low don't know, I don't pay attention I just fly the airplane, I don't concern myself with those things, just do it, is my saying.

Have fun and fly safe.

Dave S
03-29-2011, 05:59 PM
Roger,

Let me focus on your question - either way can be done 1) Crab down final and go to wing low at a reasonable point before touchdown (reasonable depends on personal preference) 2) Go wing low all the way to touchdown.

I think a person can argue either option. The one I find preferable - for the reasons which occur to me is to do the crab thing throughout the pattern and switch to wing low on short final (obviously early enough to get organized for touchdown) a) crab provides full lift from the wing while a wing low destroys a bit of the lift (wing low is a slip into the wind):) b) flying a crab to short final gives a person a pretty good idea of the cross wind change as you descend in a crab - always seems the wind changes as you descend anyway:) c) flying a crab and minimizing time in a wing low tends to provoke fewer questions from the other seat.:rolleyes:

Bottom line - both are correct and neither are wrong.:cool: The best pilots mix it up and do either at any particular time for no particular reason.

Cheers,

Dave S
KF7 Trigear

rogerh12
03-29-2011, 07:56 PM
Thanks guys for all the info and insight.
It does seem to me that in a STRONG crosswind, holding wing low all the way to the ground, you have to land faster becuse your wing are not-so level AND also you will run out of rudder at some point (to hold the noise streight) o wing lowness (and maybe drag your wing on the ground. Therefore, logically, (with a monty python accent) I should use wing low landings (as that is what I have been trained to do mostly) BUT crabbing would be a better choice in really strong cross winds (for me anyhow).

Thanks again !!!!
Roger

akarmy
03-29-2011, 09:44 PM
So I, like the rest of you fly the wing low approach near the ground and land on 1 wheel etc... But the other night I was watching the new series "Flying Wild Alaska" which is about the various bush operations of this family. What they were showing for a crabbed approach in heavy crosswinds was quite different. They flew the crab all the way to the ground, then at the exact moment they flared and touched down hit hard rudder away from the wind to bring the nose in line with the runway. The upwind wing never went down and they landed lined up. Of course it was being done in Cessna 207 & 208's not Kitfoxes...

I say find a good wind and get out and practice like Steve does!

montana_jim
03-30-2011, 12:05 AM
If you are carrying passengers, the crab is usually preferable. Most non-pilots don't like to land at an angle. Otherwise, it is what you are most comfortable with.

Monocock
03-30-2011, 12:10 AM
Vetdrem

You were misunderstood earlier I think. However, I am with you and your technique. Nose in direction of travel and a 2 pointer on upwind 'main' and tailwheel and allowing the downwind main to touch down when it is ready (after flapperons run out of effectiveness). Works superbly. I normally crab on final until about 100 feet or so as it is more comfortable, especially with a passenger.

DesertFox6
04-02-2011, 06:49 PM
There is definitely an art to flying with a crosswind component; an art that requires different brush techniques for different effects, to be sure, but the desired outcome is always to be able to look at the finished product as a work of art and not a crumpled canvas.

I've been mulling over this thread for several days now, and have to make some less than laisser faire observations, especially geared to the newer pilots in our "Kitfox Kommunitee." The older goats will ignore me anyway...:D

You can never go wrong having your tires paralleling your INTENDED ground track throughout the process, one at a time, if need be, and never letting your tailwheel's ground track get OUTSIDE those of your favorite 6 x 8s. I would never recommend landing in a crab with any GA taildragger, with any crosswind component, since it reinforces potentially bad or even dangerous habit patterns. Taildragger pilots don't need those.

This clip on landing taildraggers is currently appearing on the "Ladies Love Taildraggers" website (really cool site, too!) and serves as a reminder of what can go wrong when you're not paying attention to the details.

(http://www.youtube.com/watch?v=wSbaD8u0v58&feature=player_embedded)
http://www.youtube.co/watch?v=wSbaD8u0v58feature=player_embedded (http://www.youtube.com/watch?v=wSbaD8u0v58&feature=player_embedded).

While this clip is a composite from several sources, including Hollywood's own Robert Taylor, in a Navy flight training clip from WWII, I would venture to say all of the pilots in the landing mishaps depicted thought they had total SA, control of the aircraft, enough experience to handle the situation and didn't concern themselves with what the physics department in the back of their minds was saying because they were too intent on "just doing it."

Some appear to have opted for a three-point, full stall, landing when the situation clearly dictated a wing low, tail-high, wheel landing as beautifully, and correctly, demonstrated by a DC-3 driver in the clip. That said, here are some pertinent points I've always considered worthwhile:

1) Flying in a crab down final, as pointed out earlier, is an excellent way to determine what the winds are REALLY doing as you get closer to the ground. Correct for what you find near the runway; not 1000 feet up and two miles out.

2) Use the rudder first to align your ship with your intended ground track, even if it's canted across the runway/taxiway/cow pasture and kill your drift by lowering the upwind wing with the minimum bank required and, hence, minimum loss of energy. This entire situation is an energy-depleting slip to begin with; why lose energy needlessly? This caveat will make the next step clearer...

3) If you can't keep the aircraft from drifting from your intended landing track, I must opine, it's not "crab time," but "go someplace else time." If no "authorized" landing spot is handy you might consider landing on some other surface, even if it's a taxiway, but you'll have to have your alibi ready if the FAA (Motto: We're not happy 'till YOU'RE not happy!) comes inquiring. I say "go elsewhere" because:

4) If your full-throw rudder authority isn't enough to keep your fuselage aligned with where you want to go at final approach speed, how effective will it be when you are slower, in the flare, and in need of even MORE rudder deflection just to maintain what you had? If you can't track across the intended landing surface the way you planned, you're definitely going to land in a crab which may complicate your life like it did for some of the very experienced, but probably unwarrantedly over-confident, pilots in the film.

5) Remember that the first tire down is now drag: If that's the upwind tire, the weather-vane you're flying is now going to point you further into the wind, and, without enough rudder authority available, you're going for an unplanned, but panoramic, ride.

6) A decision to make a three-point, full stall, landing in a strong crosswind should be carefully assessed because you may be deprived of the rudder authority you still need: It may be prematurely blanked by the fuselage at a velocity that, in a wheel landing, might still offer directional control until, and/or up to, a point where you can make a continue-to-land or go-around decision. Whatever: just don't give up all your options at once.

6) Side-loads on tires landed in severe crabs can break the bead, if not just blow, and, for the bush-wheel types landing on rocks with low tire pressures, you can cram sand, gravel and decent-sized stones between the rim and the bead which can deflate your whole day. Renowned bush-pilot and Super Cub guru Loni Habersetzer covers this instance in one of his DVDs; Cubdriver: Alaska. One of our local Kitfox pilots found this out the hard way some years back when he landed in the "smooth desert" and promptly separated one tire from the wheel due to excessive side-loads.

7) Pivoting into a strong crosswind on the upwind tire, due to having insufficient, countering, rudder throw, will more than likely cause the DOWN-wind tire to smack the pavement at a much more severe angle to the plane of its rotation, causing more drag, (LOTS more if it blows) and a potential pitch over, because the aircraft is still moving "sideways" along Newton's already-determined plane of motion, regardless of where the nose is pointed, and that formerly down-wind-tire-turned-lump is now leading the parade of parts skidding down the strip or through the rye. Can you spell "fulcrum?" See movie for punchline...

A couple pilots in that film clip, who apparently slept through sixth-grade science class, provide the demos to this predictable predicament. The class' top graduates, though, are the ones whom akarmy describes doing the tricky landings in Alaska, and you'll notice two points in their success are clear: They had rudder authority and could align with the runway/intended ground track. They also managed their energy EXTREMELY well by paying close attention to ALL these details.

8) Structural fatigue is often too difficult to detect until it's too late, as illustrated by the Aloha Airlines 737-100 that took off many years back as a sedan but landed as a convertible sans-top, and again as recently as yesterday when Southwest put one of their birds down at Yuma with a new skylight. Of all the Kitfox body parts that sustain the most pain, the landing gear leads the list. I doubt there's a serious difference, save wheel-stance, between the tube gear and the spring gear as far as handling goes; I've had both on my Speedster. The advantages of a wider gear span should be obvious.

We all recall the humorous adages that " A good landing is one you can walk away from" while "A great landing is one where the airplane is reusable." The case can be made though, that unnecessarily exposing either type of gear to constant crab-landing side loads is arguably diminishing ones "...chance of flying your airplane again." Post-flight your machine every flight; you may catch early signs of becoming a "retractable" owner before your next launch.

9) Another sage once said "Never bite off more than you can chew." Don't think you can go right out and compete at Valdez after watching a video and buying bubble-wheels. When it comes to experimental aircraft, with no "demonstrated" crosswind component (the best the company test pilot would admit to that day) we're ALL test pilots, but, similar to the Valdez analogy, we can't just fly out to Edwards AFB and expect Uncle Sam to hand us keys to an F-35. (I already tried...sigh...:mad:)

Pick your crosswind training days carefully and build up to what you think is prudent. Start with 5 knots of crosswind and work up to 10, beyond if you wish, but don't try it all at once; be able to land with a given crosswind component in a predictable manner, repeatedly and consistently, before moving on. If you wouldn't subject your (significant loved one) to the rigors of a 25-knot cross-wind, why do it at all? Remember; your Kitfox qualifies to fit in between those parentheses too, so be kind to its legs and paws!

10) At one time or another, we were all taught how to do something "the right way." Most of that was based on someone's previous experience. Experience is a terrible teacher because it gives the (sometimes final!) exam first and the lesson later. We've been told to learn from the mistakes of others because we'll never live long enough to make them all ourselves. This is no place or time to start reinventing the wheel or second-guessing what the early aviators already learned and paid for. Think about the correct way you were taught to fly and/or land and continue to fly that way until you can prove you have a better method.

In the military we have combat "Rules of Engagement" (ROE) and for teaching we have Training Rules (TR) which are reviewed before each sortie and some of them are real bears. We review the rules as a reminder that the rules were learned at the behest, and sometimes the loss, of others. They're printed in blood. The last rule never changes: "Don't tease the Bears!"

Summary: Be cautious and prudent in your flight testing, all the time, especially when dealing with crosswinds: Build up your exposure to them and take your time. Make your wheels go in the same direction as the fuselage and vice-versa...ALWAYS. If nobody else is flying because of winds; take a hint, Sherlock! Don't rush out and try something you saw in a video or read on-line. Laws of men are made to be broken by those who press-to-test. The Laws of Physics aren't as malleable and frequently punish test-pressers with permanent effect. Treat your aircraft with the same respect you would the hottest love-interest you ever met and, finally, remember; those damn bears are watching! ;)

"E.T."

DesertFox4
04-02-2011, 09:22 PM
Good thread gentlemen. Enjoyed the tail wheel lessons. Thanks E.T. Good info. That video really gives me the pucker factor. Started reaching for seat belts on my office chair.
That little wheel in back really is in charge isn't it and the first thing all tail wheel pilots do when they climb in the aircraft is turn their backs on the little devil.:rolleyes:

I promise never to tease the bears.;)
Be safe out there.

Peteohms
03-17-2016, 07:25 AM
Even an old blind sow finds an acorn once in a while.

DesertFox6
03-18-2016, 08:40 PM
Lookin' Good, Pete!

That's the way to handle a crosswind alright; for an excellent exercise on those few non-windy Texas days, try trolling the runway on one tire like that at about 4000-4500 RPM, depending on weight, while slowly moving left and right laterally on the runway using just the rudder. It's a real confidence AND proficiency builder for sure, while being quite easy to do. When the winds DO pick up, your muscle-memory will more assuredly take over and prevent any unnecessary seat-cushion inhalation! :rolleyes:

Just insure you either take off or abort your roll before the runway disappears from view! ;)

"E.T."

Olle1975
03-23-2016, 05:51 AM
Hi,

I often come down in forwardslip and short above the runway I kick the plane straight and let wing down against the wind (sideslip).

https://www.youtube.com/watch?v=Q6ZS54_3U5k

The Kitfox III has not much space between pedal and brakes - attention to not touch the brakes because of this....

https://www.youtube.com/watch?v=aActGWgfUDo

Take care!

Olaf