side-slip for x-wind

[Hedley]

Knife edge slips, they didn't teach me that, details please Hedley

er, roll 90 degrees left (or right, your choice) and top rudder.

Not rocket science. Zero lift from the wings, with lift and
drag produced by the side of the fuselage and canopy.

P.S. I prefer right wing high because the slobber pot (air/oil
separator) is top right, and gravity feeds in that positions,
which has got to be good for the oil pressure.

P.P.S. Wet sump on an aerobatic airplane is a very strange
engineering design choice.

[iflyforpie]

This is because of how slips are taught. For example, at my ex-school forward slips were only taught above 2000 feet AGL, to use them below that was discouraged, to use them on final was a no-no. One of the common student discussions was what are forward slips used for as no practical use was ever demonstrated. And when you do use them, you get criticized.

I went through the same thing when learning my PPL at a college. As if slipping is somehow more dangerous than a regular approach. Both are safe if you maintain airspeed, and both are unsafe if you let your airspeed slip.

The best thing about slipping to lose altitude is that it can be turned on and off or anywhere in between without affecting lift coefficient: just like spoilers on gliders.


Too high? Stand the plane on its side and put the rudder to the stops. Too low now? Simply roll level and reduce yaw.

[MichaelP]

The French students I had in Thailand were not taught to slip when in France.
Tres dangereux!
So of course I spent some time teaching them slipping.

All those vieils pilotes who flew Stampes and J trois aeroplanes must be suffering chagrin terrible!

[hairdo]

Which got me thinking ... (I know, bad idea) ...

What happens if you simply land a light nosewheel
trainer crabbed, with a crosswind? Initially, because
of the lift generated, there isn't that much weight on
the tires, but there is enough friction to straighten
the aircraft out, generally with a bit of honking and
whining from both the tires and the instructor in the
right seat.

The center of mass is ahead of the main gear, after
all. If it wasn't, it would be on it's tail on the ramp.

And, the center of mass after touchdown nicely
pulls the aircraft straight, in the direction of travel.

Now, I'm not saying it's pretty. Or even a good
idea. It's surely lacking in style. But maybe it's
better than wrecking the aircraft.

You decide.

Erm, well it appears that two of my students took your advice and decide to try it out. One it kinda worked out for... although we were 50ft off CL. The other didn't turn out so well. It was more of a bounce, bounce, bounce, *sigh*, "I have control", overshoot. This one would have ended up with a bent airplane as the aircraft started to porpoise and was getting worse. So, I can't recommend this idea. The problem with it is that the sideloading of the tires tends to create a rolling tendency that either makes the aircraft bounce/porpoise or gets you into wingstrike territory before the aircraft gets going straight. And that, in my opinion, is dangerous.

Sideslipping and the kick-straight (when timed properly) tend to work fairly well. And the sideslip really doesn't need to be entered until in the flare.

[KAG]

Navajo,
There is nothing in writing that prohibits side slipping a Xwind landing (except supper low wing jets like the Lear 35 or RJ where you will strike a wing) , but it’s a lot easier and smoother to do the crab and kick.
Get your slip happy FO’s to crab till 30 feet then they can transition to a slip, and progressively get lower and lower until they are basically crabbing and kicking. This will help them get comfortable doing the maneuver, as they obviously haven’t been properly taught it and are hesitant to try it.

For the record, I have yet to see any Jet pilot side slip an approach with a Xwind.

[AV8R]

crab the approach at at the last moment lower a wheel into the wind, kick rudder for alignment and ailerons slowly into wind as they lose effectiveness.

[navajo]

Thanks KAG, I'll do that.