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Wolfko

What's the proper way to "crab" onto a runway??

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Ok, here's the situation I was in. Flying into KOSU (Ohio State University) with a heavy crosswind. It was blowing from my 10 O'clock position at about 20 knots. I was angled into the wind and it appeared as though I was heading straight onto the runway, although a bit crooked. As soon as I started to power off, I veered off to the right of the runway (still about 35 feet off runway). I powered up a bit more and came back over centerline. When I went to straighten out and touchdown...off I go again. I was in the C-172 with 20* flaps. SO, my question is, what did I do wrong? Should I have went to another airport with a different placed runway, less flaps? If I land crooked, the plane jerks around a lot when the wheels touch. Thanks!

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Eagle, Basically, there are two methods used to land in a crosswind. The one used by most small airplane types is a slip. The procedure is to bank the airplane into the wind, but then use opposite rudder to align the nose with the runway. As the upwind wheel, which will be a bit lower than the downwind wheel, kisses the runway :), the controls are uncrossed and the downwind wheel drops onto the runway. The only problem with this technique is that it is possible to run out of rudder authority to counteract the bank, which means a go-around a search for another runway more aligned with the wind. The other technique -- the one used almost universally by the big iron -- is to crab into the wind right down to the runway and then, just before touchdown, to kick the crab out with the rudder and land. This takes practice and good timing. Landing with the airplane still crabbing into the wind is not a good idea (except for such things a B-52s, which have swivling landing gear bogies). The side forces are bad for tires, wheels, the landing gear and your own ability to finish the landing with wandering into the weeds.

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Use the "wing low" method. As come over the runway threshhold, straighten our your crab angle so that the plane is pointing down the runway. As you do this, bank the plane into the wind slightly to avoid drift, and simulataneously add opposite rudder to hold the runway heading. So in your example, bank to the left to keep the plane from drifting, and add right rudder as necessary to keep the nose pointing straight down the runway. Hold this right through the flare. It takes practice but works in FS as in real life.

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I would use no more than 10 degrees flaps in a 20 knot wind. For crosswind landings, I would much prefer to use the ailerons to keep a wing low and some opposite rudder to keep it on the center line as opposed to the "crab" method. You're not nearly as subject to drift when you pull back on the power. It's just a much easier way to land in a crosswind IMHO.Mark

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You need FSUIPC and check the "Automatic" Taxi wind in order to do crosswind landings in light aircraft. Unfortunately FS does not register when the wheels touchdown and the wind will still blow you sidways while rolling down the runway. With FSUIPC auto taxi, when the wheels touch, the wind goes to 1kt and it in essence simulates the "feel" of the tires grabbing the runway. That will help a lot if you can then get her to the centerline and touch down she will stay there. Then upon lift off the wind will return back to the crosswind you had before.Kenhttp://www.fsd-international.com/images/FSD_beta_tester.jpg

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He! Thanks! I didn't know that about FSUIPC.As to the discussion about low-wing vs. crab I agree that for lighter a/c low-wing is good, but with a low wing a/c the tip is gonna get real close to the pavement with wind at or above 20kts.

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You're putting the aircraft into an impossible situation. The C172 (I fly one) has a maximum demonstrated cross-wind compomennt of 15 Kts. That's what the test pilot got the aircraft to do. However, since it's not a "limitation", it may be possible to land in worse conditions.I always use the "wing low" method. Imagine you bank your wings into the cross-wind, the nose will want to turn in that direction too. You stop it from doing so with the rudder. It's at the 15 knot range that the rudder is unable to do so anymore, which is the relevance of that wind speed.In real flying, where an awkward bounce may mean the end of your aircraft, or even worse- a life, if I ever encountered a crosswind greater then 15 knots, I would go find a more suitable runway somewhere else. I'd declare an emergency and land at Denver International (KDEN) if I had to, rather than mess with something I was sure would be a disaster. Bruce.BJC, Jeffco, CO

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Ok, thanks a lot guys. I knew the crab worked well on the 737's and such. I never tried the other method for the small GA crafts. I'll have to practice that. The main reason for such a high angle of flaps you may ask... I was trying to go really really slow and still have lift so that I could try to land a bit crooked without flipping the airplane! I figured I was doing something wrong since I couldn't land at all...

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Ooof!!!!You can actually see the upper flaps buckling in a couple of those. No way that airplane go away without complete LH wing replacement!A good thing they closed that airport. Unstabilized approaches predispose one to "good" landings, if you remember the old wheeze about a "good" landing being one you walk away from. However, an ideal landing is one that leaves the aeroplane in a reuseable condition. --BeachComer Stephen "Beach" Comer Real World Pile-it Commercial ASMEL, Instrument Airplane 4500 TT, 2500 BE20 & BE10

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I learned to use the slip method when training in Pipers 20+++ years ago, but hated it. Later on, my friend, who was also a former WWII heavy bomber instructor, taught me the "kick out" (crab) method that the bigger planes use, and this was well documented in a recent article by Barry Schiff in 'AOPA Pilot'magazine (yet another good reason to join AOPA).For low wings, the crab / kick out method can work very well, I have have found it both easier and certainly less disturbing to any non-pilot passengers on board. I dare say it was the only method that allowed me to get into TEB one day, when gusts were to 29 knots!For high wings, I think there is little choice but to slip, and make sure that wing is low. If you don't do that, the wing is often still out of ground effect, and there's too much room for the wind to catch it and, well, I have a bent prop in my garage from a Cessna that got caught like that (no, I was not flying it). We also used to have a C-210 parked near us at TEB. One day he came back with a smashed wing tip, bent prop, and totalled engine.At least with light aircraft, when the wing is high, keep the wing low with strong cross winds.I watch a lot of landings at CDW, and I find the Cessnas always slip it in, while most of the low wings crab it in. We only drop the wing at the last moment, or as Barry Schiff described it, "a slip interrupted by a landing". That is basically what you do with the kick out method; crab it in, and kick it out while dropping the wing into the wind so the main gear touches. Barry first witnessed this method on a 707. Works very well on an Piper also!Regards,http://www.dreamfleet2000.com/gfx/images/F...R_FORUM_LOU.jpg

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I just wanted to clarify for anyone who may be interested that a 20 knot crosswind is not necessarily the same thing as a 20 knot cross-wind component. In the original post in this thread, he mentions a crosswind from "about 10 o'clock" of 20 knots. A certain portion of that wind is a headwind component. That's where the funky little chart in the POH comes in...to figure how much of that 20 knot wind really is a crosswind....and hence, whether the wind exceeds the max demonstrated crosswind component.The only time that a crosswind and crosswind component are the same is if the wind is blowing at an exact right angle to the aircraft.MarkKDFW

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