Disengaging the wheel brake for take-off

[Iridul]

This is a silly question (forgive me!) but I seem to have real issues disengaging the wheel brake fully when I start my take-off roll.

 

Quite often my speed increases to around 50mph but gets 'stuck', I stop accelerating or continue accelerating but really slowly, leading to very (very!) long take off rolls before I get up to 100mph. (sometimes my MP fails to rise above 40, but I suspect this is a seperate engine management issue).

 

I typically disengage the parking brake by using the toe brakes, is this correct? I have real issues in setting the parking brake in the first place with my hotas/panel setup, I've never seemed to be able to get the bindings right, which may be half the problem.

 

Also, what does pulling back on the stick during the start of the takeoff roll achieve? I read that I should do it, but I don't understand why

[razo+r]

Pressing brakes does disengage parking brake. 

 

Pulling back on stick during takeoff roll doesnt do much, except with this you run into the danger of rotating too early and harsh and then stall and flip. 

 

For engine, go full RPM, mixture auto rich, Full throttle and then use boost to reach 52 inch MP. 

[grafspee]

Puling stick back for take off, induce additional pressure on tail this push tail wheel in to the ground making it more efficient in keeping plane straight when wheel is locked for take off.

Also it reduce tail wheel ware due to reduced skidding.

Issue with MP, is probably because you are not warming up your engine properly, or you didn't set up proper for take off.

Makes sure that rpm is set to max before take off and propeller governor is switched to automatic.

Make sure that boost lever is in interconnected if you want to use turbo for take off, if not boost lever should be pull back.

Primer has to be locked, other wise it will couse power fluctuation at take off.

Edited May 27, 2021 by grafspee

[Iridul]

Thanks both for the tips, I think I need more practice too!

[Art-J]

I think about 42" is the highest MAP you can get without turbocharger, and only close to sea level. That's probably why you struggle with getting to 40 sometimes. As mentioned above, linking throttle and turbo is required to get more power.

 

You might also want to enable control window as well (Ctrl Enter) to confirm your brakes aren't on by mistake because of some duplicated control assignment.

[grafspee]

28 minutes ago, Art-J said:

I think about 42" is the highest MAP you can get without turbocharger, and only close to sea level. That's probably why you struggle with getting to 40 sometimes. As mentioned above, linking throttle and turbo is required to get more power.

 

You might also want to enable control window as well (Ctrl Enter) to confirm your brakes aren't on by mistake because of some duplicated control assignment.

46" is max w/o turbocharger at SL, at elevated airfield max MAP will be lower like you said.

With turbocharger you can get much higher but max take off limit is 52". Turbo has some lag at lower rpm, so for take pushing throttle and boost lever wont give you instant +46 MAP, additional boost from turbo comes later when engine hits 2700rpm

Edited May 27, 2021 by grafspee

[Iridul]

So it turns out that DCS was only picking up my toe brakes at half deflection, rather than full deflection, so it wasn't disengaging the parking brake.

 

A quick change to axis saturation and it's suddenly much easier to take off!