Pulls to the left when airborne and crashes: Bf-109

[franx]

Fellas,

 

Everytime I get off the runway with the Bf-109, as soon as it gets airborne, it pulls to the left, flips over and crashes.  I have no idea why.  What am I doing wrong??

[andyw248]

Tell us something about your configuration, e.g. do you have rudder pedals or a twisting joystick, how did you map your controls and buttons, etc.

[LittleJP]

Are you pulling back on the stick to take off? You really need to let it fly itself off.

[JohnHardtack]

Propeller torque effect

Torque effect is the influence of engine torque on aircraft movement and control. It is generally exhibited as a left turning tendency in piston single engine propeller driven aircraft.

According to Newton's law, "for every action there is an equal and opposite reaction," such that the propeller, if turning clockwise (when viewed from the cockpit), imparts a tendency for the aircraft to rotate counterclockwise. Since most single engine aircraft have propellers rotating clockwise, they rotate to the left, pushing the left wing down.

Typically, the pilot is expected to counter this force through the control inputs. To counter the aircraft roll left, the pilot applies right aileron.

It is important to understand that torque is a movement about the roll axis. Aileron controls roll. Prop torque is not countered by moving the rudder or by setting rudder trim. It is countered by moving or trimming the aileron.

This correction induces adverse yaw, which is corrected by moving or trimming the rudder (right rudder).

 

With the Bf-109, both right aileron and right rudder are required, moreso at the beginning of roll and especially as power reaches full throttle.

As you strive to keep center-line alignment, you should apply down-elevator to lift the tail-wheel off the runway and allow you to see down the runway more easily. As speed increases, and rudder authority becomes more evident, you need to slowly back off on both right aileron and right rudder to maintain center-line alignment. As rotation speed hits 180 kph you pull the nose up and listen for the sound of the gear coming off the runway. Pull the gear up and at the same time decrease throttle input. This will reduce the propeller torque effect drastically.

 

Hopefully this helps.

Edited January 17, 2015 by JohnHardtack

[franx]

Fellas, THANKS.  I think I was too heavy on the stick.  Just had a smooth and perfect take off. 

 

Can I ask a stupid question though.  I do use the rudder pedlas effectively, but what does the aileron do and how do you typically control it?

 

Fantastic feeling after hours of frustration, actually getting the bird off the ground.

[indiaciki]

I just saw a video for the DCS bf109K. It says that you should use full aileron to the right on takeoff until you reach about 50-100 km/h. Having read all the original messerschmitt manual E-K invl.the USAF evaluation and the finnish malual that translated into english - there is no mention on using ailerons on takeoff at all. Stabiliser trim nose down at +1 or +1,5 is mandatory as well as flaps down to second mark. You really don't need full throttle to take off. Just watch you speed and lift the tail as soon as possible 100 km/h then she accelerate easily to 180-200. And as mentioned before once you're airborne decrease throttle and don't climb until your airspeed is above 250, gears up, flaps up and you'll be at 300 km/h in no time. There are some 109 aces interviews on youtube adressing the issue of her tending to break to thr left. Just let her go left and dont worry too much. Just keep her level until she's stable.

[69th_chuter]

Using full right aileron is going to require more right rudder to counter and full rudder may already be in use, depending on power setting.  One would think precession would also push the nose left during a early, quick tail lift, but it just isn't there.

[Siipiorava]

Can I ask a stupid question though.  I do use the rudder pedlas effectively, but what does the aileron do and how do you typically control it?

 

 

 

The ailerons control the planes rolling left and right, you simply use them by moving the stick left or right.

[303_Kwiatek]

Ailerons during take off have to be used only with croswind operations.

 

Torque effect on the ground is not so important,  most noticable effects during take off is  prop wash ( these is most noticable during initial take off run)  and Gyroscopic effect ( with taildraggers).

[StG2_Manfred]

The ailerons control the planes rolling left and right, you simply use them by moving the stick left or right.

You made my day, Siipiorava This is just brilliant

[franx]

Excellent, thanks all.

[Gustang]

It sounds like you got it worked out, Franx, although "flips over" sounds an awful lot like a reverse axis problem I had when I first started configuring my controls for the game.   I must have tried taking off 2-3 times with an incorrect setup before I realized my x-axis was reversed.    

 

Anyway, it's another reason why it pays to check your control surfaces on the ground.   In this case, when you push the stick to your left, the left aileron should push upward.   

[-NW-ChiefRedCloud]

I just saw a video for the DCS bf109K. It says that you should use full aileron to the right on takeoff until you reach about 50-100 km/h. Having read all the original messerschmitt manual E-K invl.the USAF evaluation and the finnish malual that translated into english - there is no mention on using ailerons on takeoff at all. Stabiliser trim nose down at +1 or +1,5 is mandatory as well as flaps down to second mark. You really don't need full throttle to take off. Just watch you speed and lift the tail as soon as possible 100 km/h then she accelerate easily to 180-200. And as mentioned before once you're airborne decrease throttle and don't climb until your airspeed is above 250, gears up, flaps up and you'll be at 300 km/h in no time. There are some 109 aces interviews on youtube adressing the issue of her tending to break to thr left. Just let her go left and dont worry too much. Just keep her level until she's stable.

 

What he said ..... yes +

 

Chief

[indiaciki]

just foung this:

 

Take-off

This is best done with the flaps at 20 degrees. The throttle can be opened very quickly without fear of choking the engine. Acceleration is good, and there is little tendency to swing or bucket. The stick must be held hard forward to get the tail up. It is advisable to let the airplane fly itself off since, if pulled off too soon, the left wing will not lift, and on applying aileron the wing lifts and falls again, with the ailerons snatching a little. If no attempt is made to pull the airplane off quickly, the take-off run is short, and initial climb good.

 

E model.

Edited January 22, 2015 by indiaciki