missing info Landing touch-down pitch up moment is too great.

[Nealius]

"Main fuel" = full outer tanks + full inner tanks, then? 

I can try more touch and go's to test. Would 30% fuel be low enough?

[SMH]

[Nealius]

Just tested starting at 30% fuel, not sure how much I burned in the 40 minutes I flew but the inner tanks were pretty much empty. 15,900lbs. No noticeable difference in tail-down moment from 67% fuel (~17,100lbs). To avoid a tail-down moment I still have to stuff the stick forward before the tires touch the runway. 

Edited October 19, 2021 by Nealius

[Terry Dactil]

6 hours ago, Nealius said:

To avoid a tail-down moment I still have to stuff the stick forward before the tires touch the runway. 

 

And that is where the error is.
You should not have to do that.

 Consider the following ...
 The aircraft designers have done their sums and worked out what force will break the undercarriage or have other bits fall off the aircraft.
 They then apply a safety factor to get the maximum that will be allowed. This has to be converted into something that will be useful to the pilot.
 This is where our friend Newton and his laws of motion are very useful.

•  Starting with F = Ma  we see that for any particular aircraft weight (M) the force (F)  depends on the vertical velocity deceleration on touchdown (a).
•  Next  V² = U² +2aS shows that deceleration can be reduced by a squishy oleo on the undercarriage providing a large distance (S) in which to stop the vertical velocity.
•  The U² term now gives us the initial vertical velocity or the maximum sink rate on touchdown which the pilot can understand and has some control of.

 (In commercial airliners I have flown this limit is 600 feet per minute. Anything above about 200 fpm is a hard landing dangerous to the fillings in your teeth and causes passengers to complain)!
 
 The next bit gets more complicated.

•  Because the weight (through the CG) and the ground reaction force (through the wheels) are not vertically aligned, there is a torque applied in the pitch plane.
•  This will produce a rotational acceleration in this plane which depends on the rotational moment of inertia , and I have no idea what this value is.

 This could be the missing ingredient causing the error.
  I'm pretty sure ED account for this in other aircraft. The tricycle gear aircraft  have the reverse touchdown dynamics (pitch down) to taildraggers and they don't have the nose wheel slam down immediately on touchdown.
 
  Fix the Mosquito. Pretty please!

[Nealius]

The suspension feels bouncy as well. Touching down at less than 100fpm on the VVI and I still bounce like I'm landing on a trampoline. In the video posted on the first page the suspension looked much stiffer than ours in DCS. 

I'll try some more pattern work with 0% ammo and 10% fuel just to see how light I can possibly get this thing and still fly. We are well under maximum landing weights even with full ammo and 67% fuel. 

Edited October 20, 2021 by Nealius

[RodBorza]

On 10/3/2021 at 4:22 PM, No1sonuk said:

I keep getting tail strut failure messages in the debrief.
Is that because of this, or am I just landing too heavily?

Yes, you might be.

When coming to land, instead of cutting power on final, keep the engines running. Use pitch to control speed and throttle to control rate of descent. You can/must do this to all allied warbirds. They tend to lose speed, thus lift very fast.

The Mossie is very stable at landing speeds, which are around 110 - 120 mph. You can come down at 130 mph, then at final, lift the nose to slow down to 120 and then touchdown at 110 mph. It takes some practice but works well, for the Mossie, Spitfire, P-51 and P-47. But remember, don't cut the engine, keep it with a little bit of throttle until you touchdown, to arrest your descent rate.

 

[Terry Dactil]

On 10/4/2021 at 6:22 AM, No1sonuk said:

I keep getting tail strut failure messages in the debrief.
Is that because of this, or am I just landing too heavily?

The excessive nose-up pitch on touchdown is probably part of the problem too.

[Basco1]

16 minutes ago, Terry Dactil said:

The excessive nose-up pitch on touchdown is probably part of the problem too.

Terry one of the things you must do on landing the Mossie is to alter your trim pitch to counteract this.

[Nealius]

2 minutes ago, Basco1 said:

Terry one of the things you must do on landing the Mossie is to alter your trim pitch to counteract this.

How much trim are we talking, because I land with greater than 1.0 nose down. Probably 1.5. 

[Basco1]

47 minutes ago, Nealius said:

How much trim are we talking, because I land with greater than 1.0 nose down. Probably 1.5. 

I'm not sure how much,I don't tend to check the amount,just enough to counteract,but as soon as you extend your flaps you must be in a nose down pitch attitude,to counter act the nose up attitude that becomes very apparent once the flaps are extended.

It's in all the tutorials I have watched and I'm pretty sure it's mentioned in the DCS Mosquito Landing training tutorial you know,the one where you have to fly down through the boxes.

Once in this attitude just use your stick pitch control to fly in straight and level,approach speed at 120mph and flare slightly as you cross the final threshold,well that's how I control my landings anyway,right or wrong.

Edited October 21, 2021 by Basco1

[Nealius]

Is this after the recent update? I've flown her a lot prior to the recent update and hardly noticed any pitch up moment when deploying flaps. I'll drop gear just below 180, drop flaps between 140 and 160. If I keep power on I might get some pitch up, but I keep a very low throttle setting and neither the nose nor the VVI does much when the flaps come down. I don't recall ever touching pitch trim in the pattern. 

[Basco1]

3 minutes ago, Nealius said:

Is this after the recent update? 

No,I've always adjusted my nose trim down once flaps are extended on landing.