Pilot_DAR wrote:
Touched down fully crabbed and held it….
Is it me or does that photo not look like its actually a wing down (ie crossed controls) landing? ie specifically NOT a crab…Am I missing something?
Well all I can say is that around here we do it regularly in some pretty strong crosswinds, and we’re not ground looping regularly.
Despite being dominant the wind is not always from 26 or 08. In fact these last months it rarely has been. And the land round here is pretty flat, crosswinds from 20kts to 30kts are regular features during the day. They often calm in the evening.
But if you feel better with your technique then that’s the method you should use IMO. On here, most of us are trained pilots and can make our own decisions.
Add a tail wheel and a bit of gust on tarmac (high friction surface). Relying exclusively on crab technics sounds like a ground loop is going to happen any day.
Elementary indeed my dear Watson.
So what is this debate about?
The ‘kick it out of the crab’ technique is what I described in my post slightly above and along with slipping has been taught to every US private pilot I’ve met, since the dawn of time. Since you don’t fly around in a slip under normal conditions, the issue when landing is only at what height you transition out of the crab. Some planes work better slipping all the way down final and modulating the slip to both counter the crosswind and control descent rate. Often this works well on types with no flaps. Other types don’t comfortably slip due to e.g. heavy rudder control forces or some aerodynamic defect, so they work better when crabbed almost all the way to the ground.
What hasn’t been much discussed here is that the same technique is used in reverse on takeoff: when properly controlled in a cross wind the aircraft leaves the ground in a slip and once you feel positive rate of climb (or at least no chance of contacting the ground again) you let it crab and further increase climb rate in doing so.
All this is elementary flying technique that should be very familiar to any pilot.
gallois wrote:
It seems the technique is not widely used in GA outside France but it was a method I was taught and I find it works for me.
I was taught the same technique in Sweden, in 1984.
There’s possibly no reason why not on ice. As I wrote I have never landed on an ice lake or similar.
Crabbing is used to stay on a normal approach with the nose into the wind and on the centre line and wings level. The same as you would do in a flight from A to B with the wind coming from the left or right whilst maintaining the magenta or green line.
So if the wind is coming from the right your heading is to the right of the runway but the nose stays on the centre line.
Just before touch down, usually in the flare you turn the aircraft to line up with the centre line by pushing the left pedal as you would do in a soap box cart. However, if you did nothing else a strong wind might well lift the into wind wing or push the aircraft left. So you add into wind aileron at the same time as pushing the pedal. How much depends on the aircraft. But as the aircraft slows along the runway and depending on type of aircraft you may need to add more into wind aileron to stop the aircraft from turning.
In a Robin 300/400 for instance on take off and landing in a cross wind you can just about use full aileron from applying power to wheels leaving the tarmac and the reverse when landing, to keep you straight during landing and take off roll. In a Seneca or Seminole you need to reduce the amount of into wind aileron as you speed up during take off and add it whilst slowing down during landing.
It seems the technique is not widely used in GA outside France but it was a method I was taught and I find it works for me. I have tried coming down the centre line on short final with into wind wing tilted towards the wind and keeping aligned with the centre line using rudder and keeping that configuration until touching down wing low and on one wheel. I decided that the crab technique suited me better.
gallois wrote:
But why land crabbed instead of decrabbing just before the wheels touch and having the airctaft lined up with the runway heading, instead of putting sideways strain on the landing gear?
Certainly on a friction surface, I would minimize sideload on landing gear. On ice, it’s not a factor, which was why I was practicing that day. It was all about control, what could I make the plane do, both into the wind and crosswind. Yes, it is certainly possible to land wing low without being fully crabbed, and to land in an intense crosswind without lowering a wing much, I just like to practice when conditions invite. A frictionless runway which is ten miles in all directions is too inviting to resist!
Why not, he’s on ice so there wont be much side load at all.
One thing I don’t quite understand is that the image looks as if you’ve got one wing low, whilst I thought landing crabbed would be wings level with the fuselage pointing in a different direction to the track over the ground
But why land crabbed instead of decrabbing just before the wheels touch and having the airctaft lined up with the runway heading, instead of putting sideways strain on the landing gear?
