There are two main schools of thought about the best way to set up a landing in a crosswind. The first is the wing-low “side-slip” approach, in which a pilot attempts to prevent wind drift by keeping the wings banking into the wind while cross-controlling the rudder to keep the fuselage aligned with the runway centerline. However, akin to balancing a marble on a bowling ball, probably fewer than one percent of RC pilots have the skill to attempt this. (It’s easier in full-scale aviation because heavier airplanes are more stable in wind and thus easier to slip). Furthermore, as the majority of expert pilots know, it’s often a waste of time and mental energy to side-slip before getting near the ground because, due to the influence of the terrain and surface friction, the winds are constantly changing the closer the plane gets to the ground. Consequently, while it’s always good to anticipate what is coming next, a pilot won’t actually know what wind corrections will be needed until shortly before touchdown.
The pros—the ones who make everything look easy—use the easier approach of allowing the airplane to crab into the wind until shortly before touchdown. In reality, expert pilots pay little attention to where the plane is pointing or how much it is crabbing during the approach. Instead, our only concern is keeping the airplane as a whole tracking the centerline and executing a perfect flare. We will then smoothly kick out the crab right before the wheels touch while continuing to counter any drifting with the ailerons as needed. The great thing about RC is that our vantage point outside the airplane makes it easy to see when the wheels are about to touch, and thus exactly when to kick out the crab.
The best solutions are usually the simple ones: expert pilots don’t pay much attention to whether the wings are banked into the wind or care which wheels touch the ground first, only that we distinguish ourselves by touching down smoothly and perfectly tracking the centerline. If the upwind wheel happens to touch down first while we’re making the necessary aileron inputs to keep the airplane over the centerline, that’s fine, but maintaining the centerline and smoothest possible touchdown are always our primary concerns.
BY DAVE SCOTT, 1st U.S. R/C Flight School
Kicking out the crab just before touchdown is how the pilots in big planes tend to do it also. I was the way I did it.
As a full-scale as well as giant RC pilot, I was happy to see that you made the distinction on the low wing approach (what I call a “forward slip)and how, given the weight of a full scale plane, it is easier to do on full scale than a model. Also, the truth that when holding a crab in an RC model, the pilot is able to see exactlly when to take the crab out. As I’m sure you know, if you time taking the crab out poorly on a full scale, the side load on the gear can be a real problem.
Thanks for the good article.
I am certainly glad you posted this. I have fought for the past several years to learn that slipping technique since a very good pilot flying buddy of mine tried to teach me. I realize after reading your article that I was actually making much better landings before I tried it! Thank you.
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