prop-wash questions

[Sohail]

Jonathan, you are right, I need to be in control and fly the plane rather than let it fly me
Geoff, I am going to try centerline under my seat and aggressively control any deviation.

I will not be able to fly for another 10 days, taking the kids on spring break to CA. I will post the results when I come back from my next flight.

Thanks for the tips.

 

[flyingcheesehead]

Machfly, this is all withen the first 1/2 of takeoff before wheels off the ground.

Definitely pay attention to these:

1) How you add power
2) Position of your feet on the pedals. You may be occasionally getting on one of the brakes without realizing it.

Hook Dupin, I remember a nasty day where I would hit a updraft and cut throttle 100% and nose down and still be gaining alt and then the next moment I would 100% throttle and raise nose and loose alt. as a new pilot that was really disconcerting to me!!!

You were probably making it worse by doing all that - For example, by the time you got to the end of the updraft, you were at idle power with the nose down and so when you hit the downdraft you lost altitude REALLY fast, and then had to try to make it up... Then the opposite would happen. Try leaving power alone and just riding with the bumps a bit. In fact, one of the best things you can do is to just go out in the practice area, stabilize the plane as much as you can, and then just let it go. Don't touch the stick at all. Allow yourself one trim change every minute, just enough to reverse a trend in altitude. Make it small enough that you don't have to go the opposite direction the next time, and keep the magnitude of the change smaller every time. You'll soon find that you don't need to make any trim changes to keep the altitude within a couple hundred feet, the airplane's stability and the average updraft/downdraft will be in equilibrium. THEN, use the stick to maintain altitude. Don't change the throttle at all. That's how you want to fly.

 

[flyingcheesehead]

I failed my checkride yesterday because I could not control the nose of the DA40 :-(

If I may be so bold, I would suggest that it's "did not" rather than "could not." Did you ever have the rudder all the way to the stops? It seems that people are afraid to actually use all of the control that's available to them and instead of flying the plane, they let the plane fly them.

Every takeoff or landing is different (over 200 so far), I am almost always drifting to the left side no matter how much is the crosswind or how hard I press the right rudder whether it is takeoff or landing. Any ideas?

Do *everything* as consistently as possible. Add throttle at the same rate, use the same amount of force to pull back the stick, and don't be afraid to be aggressive and quick with your rudder use to keep the nose pointed down the runway.

That said, don't over control.

Also, think in terms of *pressure* on the pedals, rather than deflection of the controls. As you change speed, the effectiveness of the controls will change. For example, let's say you've got a constant crosswind from the left. You'll want to start with full rudder *deflection*, and if necessary, use a tap on the right brake as well to keep the nose pointed straight down the runway. But if you keep full deflection, you'll eventually turn right and go off the runway. When you can let the pedal off the stop, pay attention to how much pressure you're putting on it, and try to keep that pressure constant. As you speed up and the controls become more effective, the *deflection* of the controls should decrease, but the *pressure* you put on the pedal should remain the same.

This is very similar to what you should be doing with the other flight controls, but it's a lot harder to feel that finesse with your leg instead of your hand.

Bottom line, just make the plane do what you want it to.

During takeoff and landings I feel like a fish with my rear wagging left and right. Any ideas from more experienced pilots please who are familiar with DA40-XLS? Thanks

If you're wagging in both directions, either you're overcontrolling, or you're using brakes to stay straight. The rudder on the DA40 becomes effective at pretty low speeds if you have power in - Try to stay off the brakes.

 

[flyingcheesehead]

so I am at the numbers in DA40 on the left seat looking down the runway centerline, should I push the right rudder all the way before pushing the throttle or only push the rudder in reaction to turning left.

I would start with the rudder all the way to the right, and then slowly release it to track the centerline. Ron's suggestions of staying on the brakes and standing still until you've got a good amount of power in, and starting pointed just a hair to the right are good ones.

In a DA40 with the large rudder (which includes all of the XLS models), you should be able to do your takeoff without any braking under most conditions (unless there's a REALLY strong right crosswind).

 

[Sohail]

I am back from vacation... tried "heavy" right foot and was able to keep the plane almost in the middle on the centerline... Now a new problem which I think can be solved with more practice i.e. now my tail zigzag during take offs which means I am overcorrecting with right foot. I am still uncomfortable with cross-controls on short final. I am going back for another lesson this weekend. BTW, I did not use the brakes during takeoffs just the full rudder.

 

[Jimmy cooper]

If you invest 10 hours in a taildragger, with a good instructor you may find that your stated problems are solved.