A-20 propeller torque on take-off

[TAIPAN_]

The A-20B props rotate clockwise similar to the Ju-88 and He-111.

 

However it doesn't have a strong pull to the left on take-off rolls like the German twins, in fact it travels down the runway in an extremely straight line as if it had counter-rotating propellers.

 

Does anyone know why this is? Some kind of torque control system or different power between the two engines enough to make any difference?

[Yardstick]

I'm no expert on any of these aircraft but the A-20 has tricycle gear while the other are taildraggers.  I think the centre of gravity relative to the position of the undercarriage has a big impact on the effect of torque.  Others will no doubt have better / fuller explanations.

[TAIPAN_]

1 hour ago, Yardstick said:

I'm no expert on any of these aircraft but the A-20 has tricycle gear while the other are taildraggers.  I think the centre of gravity relative to the position of the undercarriage has a big impact on the effect of torque.  Others will no doubt have better / fuller explanations.

 

I totally missed this part and didn't even look at it from the outside ?

 

That pretty much explains it I think.

[sergio_]

P-factor is the effect  I think you refer to.

The more upwards the nose is pointing, the higher this effect is.

Therefore a taildragger on take off run will have a higher effect than in a tricycle.

Edited June 23, 2020 by sergio_
link to reference

[istari6]

I know the A-20 also sets a number of trim tabs automatically on startup ("E").  I wonder if it's already "dialed in" to counteract torque, versus a DCS-style sim where you need to set that yourself?

[LukeFF]

2 hours ago, istari6 said:

I know the A-20 also sets a number of trim tabs automatically on startup ("E").  I wonder if it's already "dialed in" to counteract torque, versus a DCS-style sim where you need to set that yourself?

 

The trim is set for all planes at mission start to the optimal cruise speed configuration. 

[Bremspropeller]

2 minutes ago, LukeFF said:

optimal cruise speed

 

[istari6]

On 6/23/2020 at 12:38 PM, LukeFF said:

The trim is set for all planes at mission start to the optimal cruise speed configuration. 

 

Aren't most planes from this time period designed to be neutrally stable at cruise?  I thought trim controls were mostly needed for compensating when the airplane was in other speed regimes outside cruise.  

[Guest deleted@210880]

I wonder if the A20 flies to forgivingly, I've done barrel rolls and all manner of crazy stuff online to try and stay alive, but this suggests otherwise.