There are two ways to know if a crosswind is too strong. One is to land and see if you skid off the side of the runway or ground loop. The other is to cross control the airplane before landing to see if you can align the airplane with the runway. I prefer the second technique.
When you use your rudder to align the airplane with the runway and the ailerons to move the airplane laterally over the runway, you are cross controlling the airplane.
This is a technique not used often in flight, but a very useful one to master.
Some pilots advocate flying wings level in a crosswind and kicking the rudder pedal vigorously the instant before touchdown to get the airplane pointed in the right direction. I have even seen this technique described in how-to-fly books. But frankly,this is one of those ideas that sound good if you say them fast. With this technique, you just don't know if you can get the nose pointed down the runway until you land, nor do you know if the crosswind will blow you off the runway before you're on the
surface and under control. So if your life insurance is paid up and you don't have an aviation exclusion clause, you might try the old kick-and-hope trick.
There is an exception. If you are flying a nose wheel equipped airplane with liftkilling spoilers - which means you are flying a heavy airplane, not a light plane - then you can deploy the spoilers fully the instant you touch down and let the plane swivel
toward the far end of the runway. I would refer you to that now famous Lufthansa crosswind landing. Its URL is http://www.youtube.com/watch?v=z42fchrzhHY . As you can see, even that technique requires some rather precise timing. I have seen
some videos of the A380 and some B474s successfully using this technique. They were flown by multi-thousand hour test pilots. I don't think it is in the cards for someone flying a light plane.
Passengers find cross controlling disconcerting. All of us like the floor to be directly beneath us and the seat to feel level. Cross controlling to align the wheels with their direction of travel requires that the upwind wing go down and that the pilot press - sometimes vigorously - on the downwind rudder pedal. Suddenly the floor is no longer level and the seat sits at an angle. This is all very upsetting to the passengers.
What to do?
I recommend practicing entering the cross controlled state just as you start to raise the nose to land. This is the optimal technique and only requires slightly more skill than the procedure I describe a little further on.
The wing loses lift when it is cross controlled raising the airplane's stall speed slightly. If the airplane cannot be cross controlled enough to get the airplane properly
aligned, applying power immediately and returning to a wings-level, coordinated flying condition will lower the stall speed again and get the airplane climbing. This would not be a good time to botch a go-around.
This technique minimizes the passengers' exposure to cross ontrolled flight. Nevertheless, it is better to have a isconcerted passenger than a bent airplane. So if you are not the compete master of the cross control at the last minute technique, cross control while you are still in your pre-landing glide.
If you cross control when you are a hundred feet above the urface, you have enough time to see if the airplane can be aligned with the runway before you have to start concentrating on the landing itself. If not, then you have plenty of time to smoothly
transition back to wings level and execute an un-hurried go-around. This technique is the easiest and therefore the safest. But it is the most disconcerting to the uninitiated.
So let your passengers know before you do it, that this is a necessary and safe procedure. An important point here is that you should keep cross controlled all the way through the landing and during the roll out.
A lot has been said and written over the years about crosswind landings. It all boils down to having your wheels pointed in the same direction you are traveling before you touch down and knowing if you can while you have enough time, altitude and airspeed to easily make a safe go-around.
For flying techniques visit http://PrivatePilotTrainingOnline.org/OP .
No comments:
Post a Comment