Two point landings

[j.sabo12]

Hello guys, 

Playing around with the finer points of the Mosquito, and having a bit of a hard time with nailing two point landings. I can do them without too much issue in a P-51  and P-47, and in real life (albeit on a somewhat more modest Zlin-226). 

Also, the Mosquito in Il-2 BOS is not an issue at all for this. 

What I find with the Mosquito in DCS is that it feels bouncy, and there is not so much rolling resistance in the tires - as if the tires have a huge amount of pressure. Even if I touch down extremely gently at the correct speed, I find myself bouncing back up into the air and having to come down to a three point landing. 

Anyone have any tips? Either direct Mosquito, or DCS? 

 

Thanks :)) 

 

[Terry Dactil]

Yes, I agree with you that the Mosquito does not behave realistically for a two wheel landing.

I was fortunate in the early days of my aviation career to fly many different types of tail draggers from the Tiger Moth  to the DC-3 and the Bristol Freighter. Like you, I know that pitch up on a two wheel touchdown is proportional to the sink rate. In fact if you have a really low vertical velocity on touchdown you can actually get a nose down pitch moment due to the drag from the wheels spinning up. 

I reported this unrealistic behavior about 4 years ago when the Mosquito was released, , but nothing has been done to fix it. Unfortunately I don't think it ever will be. The Mosquito is still labelled "Early Access" but probably could be more accurately labelled "Abandoned".

I spent some time with the configuration files looking at the possibility reducing the moment arm between the CG and the main wheels but a successful modification proved beyond my capabilities. Perhaps someone more qualified reading this will take up the challenge.

 

[Mav87th]

You have these to play with in the FMOptions.lua file:

Everything inserted with ---- is my comments

 

mainWheelStaticFricK = 0.71 ---- could be to low ?? higher value will make the plane harder to get out of parking, and unknown if it affects wheel not spun up before touchdown.
mainWheelSideFricK = 0.73*.9
mainWheelRollFricK = 0.022
mainWheelGlideFricK = 0.69
mainWheelBrakeMomentMax = 7500 --18000.0
mainWheelMOI = 8.32 >>likely moment of inertia

---- could be in this section that you would want to add a little more spungyness to prevent the plane from jumping up after touchdown. Perhaps the back damper to reduce the plane from jumping

-- until pneumatics compression not implemented
mainGearSpringForceFactor = 21000000000
mainGearSpringForceFactorRate = 9
mainGearStaticForce = 30000
mainGearReduceLength = 0.18
mainGearDirectDamperForceFactor = 50.0
mainGearBackDamperForceFactor = 75000.0
mainGearDamageLengthLim = 0.0 

and  then there is the stuff that is commented out

---- perhaps the pneumatic parameters that is mentioned in section two??

-- tire&strut params
--param0 = 1100000 -- main tire k_stiff
--param1 = 2300 -- main strut f_0
--param2 = 180000 -- main strut c
--param3 = 500000 --  tail strut k_stiff
--param4 = 7000 -- tail strut f_0

 

There is some guidance to find in this post 

 

[Terry Dactil]

Well there goes the rest of my weekend.  I'll be trying some mods to those values.

Thanks Mav87th - some good info there.

For anyone else interested in joining us to in improve the Mosquito's 2 wheel landing characteristics, the file is ...

<??>:\DCS World\Mods\aircraft\MosquitoFBMkVI\FM\FMOptions.lua

Edited October 18 by Terry Dactil

[Terry Dactil]

Tried various different damper values  up to +/- 10x original without any noticeable change to the touchdown bounce.   

mainGearDirectDamperForceFactor = 50.0
mainGearBackDamperForceFactor = 75000.0

[Mav87th]

Try lowering the 

mainGearSpringForceFactor = 21000000000

in the Spitfire thread the user "mkiii" halfs the value. 

BUT also make REALLY sure your speed is low enough for the touchdown. It's imperative that the wing looses lift as(or just before) you touch down so the plane looses the ability to "jump"