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You guys have always been a big help and know I will get many opinions on this subject. We all know the Castering nose wheel on the DA40 is unique to say the least. I have 50 hours now in a 2008 XLS and I still struggle keeping the center line on the take off roll. It makes me nervous every time. When I typically hit about 50 KNTS it gets very difficult to control and it seems as I try to correct with rudder it gets worse. I always feel safe in this plane but man it seems to get squirley on the roll! Any advise is greatly appreciated

Free castering nose wheels are now common. Cirrus and Columbia/Corvalis also use them.

I'm not sure what you mean by "squirrelly", buit at 50 knots you're halfway flying already and there's very little weight on the mains. You're above stall speed and the airplane can be lifted off even below this speed.

Coming from Cessna's I understand what do you mean. It feels strange to use breaks to keep center line when you almost rotated. I'm trying to be gentle on breaks and mainly use rudder to keep the plane on centerline however if I have to I add a little pressure on breaks. It certainly makes takeoff roll longer but I use 3000'+ runways anyway.

The DA40 needs very little rudder (comparing to say DA20) to keep it on the centreline. Granted, the 172 needs even less.

The brakes are only required at the very beginning of the take off roll. Try to advance the throttle slower, counteracting with the rudder. It will be enough. Once the aircraft gets going you do not need to use the brakes anymore, the rudder is more than enough. And you need less and less as you accelerate. You certainly do not want and do not need to use differential braking once near the rotation speed. Again, the trick seems to be advancing the throttle slower (take 2-3 seconds to go from idle to full power). Once you develop a feel for it you'd be able to just get up and go, all on the centerline.

alexanderk wrote:The DA40 needs very little rudder (comparing to say DA20) to keep it on the centreline. Granted, the 172 needs even less.

The brakes are only required at the very beginning of the take off roll. Try to advance the throttle slower, counteracting with the rudder. It will be enough. Once the aircraft gets going you do not need to use the brakes anymore, the rudder is more than enough. And you need less and less as you accelerate. You certainly do not want and do not need to use differential braking once near the rotation speed. Again, the trick seems to be advancing the throttle slower (take 2-3 seconds to go from idle to full power). Once you develop a feel for it you'd be able to just get up and go, all on the centerline.

Yeah, if you slam the throttle forward to start, you won't have enough rudder to hold 'er. But once rolling AND the prop slipstream is established on the tail, no more braking should be required. Certainly not by rotation. Gusty crosswinds complicate this, of course, and you must adjust for same.

I have about 300 hours in my DA40 now, and the single thing I have not yet mastered is staying centerline on takeoff near rotation speed. I totally agree on the squirrely feeling around 50 kts. This becomes even more noticeable with high altitude takeoffs where the roll takes significantly more time. Big Bear (L35) in the summer with density altitudes > 9,500 and I'm typically meandering back and forth across the line for several seconds before liftoff. The issue I believe is that the rudder steers TOO well at that speed. If I want to steer right just a few degrees, I lightly press on the right pedal, and the plane turns farther to the right than I want. Although still not a master, what I find works best for me is putting moderate equal pressure on both pedals during the roll, and when corrections are needed, to use very quick "blips" on the pedals in intended direction then put them back to neutral equal pressure. If I try and leave the correction pressure in place, no doubt I will oversteer.

I can't say I ever notice an issue keeping the plane on centerline. Maybe you could use some training in a tailwheel airplane. That usually cures issues like you just mentioned.

I agree with Lance, coming from a Maule MX7, using the feets for t/o and ldg is the half flight.

Not sure about Lance's plane, but Thomas's 40.337 is most likely before they changed to a larger rudder style on the plane (added when 50 gallon tanks added), so might be easier to move and less likely to oversteer.

smoss wrote:what I find works best for me is putting moderate equal pressure on both pedals during the roll, and when corrections are needed, to use very quick "blips" on the pedals in intended direction then put them back to neutral equal pressure.

I second this exact approach. Coming from a C172, I definitely had problems staying neatly on centerline in the beginning as well.

Learn to correct *immediately* when getting even a tiny bit off centerline & use very brief neutral corrections - this will ensure you remain there. After a little while, you'll start to recognize the proper technique. It can be tricky...