fixed Mosquito landing gear strut incorrect operation..

[Terry Dactil]

Had an interesting talk with ChatGPT about the Mosquito landing gear.

Here is the interesting bit ...

  

So you are saying that the rubber blocks resist expansion more than compression?

Yes, that's correct. In the context of the Mosquito aircraft's landing gear system, the rubber blocks are designed to resist expansion (or rebound) more than compression.

Here's why:

1. Material Properties: The rubber blocks used in the landing gear system are engineered with specific material properties that make them more resistant to deformation during rebound compared to compression. This involves selecting rubber compounds with suitable elasticity, resilience, and internal friction characteristics.

2. Design Considerations: The design of the landing gear system takes into account the need for controlled damping during both compression and rebound phases of the landing process. By engineering the rubber blocks to provide greater resistance to expansion, the system effectively dampens the rebound motion, preventing excessive bouncing or oscillations of the aircraft upon landing.

3. Shock Absorption: During compression upon landing, the rubber blocks deform to absorb the initial shock and dissipate kinetic energy. However, during the rebound phase as the aircraft weight is lifted off the landing gear, the rubber blocks resist expansion, thereby damping the upward motion of the landing gear and ensuring a smooth transition to the fully extended position.

4. Optimization: The damping characteristics of the rubber blocks are optimized through careful selection of materials, dimensions, and configuration to achieve the desired level of damping performance while maintaining the structural integrity and longevity of the landing gear system.

Overall, the design of the rubber blocks in the Mosquito's landing gear system prioritizes greater resistance to expansion during rebound to effectively dampen the motion and provide a stable landing experience.

 

Item 3. Surely the landing gear does not rebound to the fully extended position, as it is now supporting the weight of the aircraft.

 

You're absolutely correct, and I appreciate the clarification. I misspoke there. Let me correct that.

During the rebound phase after landing, the landing gear does not fully extend to its initial position. Instead, it partially extends as the aircraft's weight is transferred off the wheels and the landing gear strut decompresses. The damping action provided by the rubber blocks slows down this extension, preventing rapid bouncing or oscillations of the aircraft.

So, to amend point 3:

3. Shock Absorption: During compression upon landing, the rubber blocks deform to absorb the initial shock and dissipate kinetic energy. However, during the rebound phase, as the aircraft's weight is partially lifted off the landing gear, the rubber blocks resist expansion, thereby damping the upward motion of the landing gear and controlling the extension to maintain stability.

 

 

( It is a bit of a worry when you find yourself saying/typing please and thank-you to an AI program on your computer ) 

 

 

Edited May 10, 2024 by Terry Dactil
typos

[Holbeach]

On 5/9/2024 at 7:15 PM, NineLine said:

There are some changes coming, but I believe Yo-Yo is trying to describe that the changes won't do everything that is expected here. 

This is what I expect to see and Yo-Yo has already said that this is what will happen.

The static position of the strut will look like this. The strut lowered to the position as shown.

An FM to go with it.

If this doesn't happen, then were wasting our time here and this thing will go on for ever.

A lot of people have said they won't fly this excellent model any more, which is a shame, because the bad experience is caused by this update.

 

 

 

..

[Magic Zach]

Holbeach is showing that the static compression distance of the MLG strut is not matching that of real life examples, which I think is a bottom-line example that shows something within DCS's Mosquito struts is incorrect.  We can assume that since DCS represents aircraft in new or near-new condition, that our strut should react more stiffly than some of these real world examples and perhaps not compress as much, but I do doubt it would be so significant as to dramatically change the landing characteristics of the aircraft as we are witnessing.
As far as this effecting bounce characteristics...
A handful of other factors aside, one thing that would influence the tendency to bounce is how stiff the struts would or wouldn't be.  The rate of change in vertical velocity changes the amount of force pushing back up on the airframe from the ground, and creating a torque around the aircraft's CoG.  Having struts that are extremely rigid like these new ones in DCS does have an effect on the bounce characteristics, not just how low the aircraft squats while parked.
I think it's fair to say that something, is wrong with how the Mosquito's struts compress in DCS at the moment.  Specifically just how much "pressure" (for lack of a better word, I know the struts use rubber not air/fluid, but you get the idea) is within the struts, which does appear to be too high.  Lower the "pressure" and it should simultaneously solve the issue with the aircraft squatting too high while parked, and it's tendency to be too springy during by-the-book landing configurations.

[Slaobladder]

On 5/11/2024 at 7:55 AM, Holbeach said:

This is what I expect to see and Yo-Yo has already said that this is what will happen.

The static position of the strut will look like this. The strut lowered to the position as shown.

An FM to go with it.

If this doesn't happen, then were wasting our time here and this thing will go on for ever.

A lot of people have said they won't fly this excellent model any more, which is a shame, because the bad experience is caused by this update.

 

 

 

..

Agreed

[Skewgear]

I organised a 6-ship raid the other night. Said to the squadron, "how about we take up a flight of Mossies tonight and smash something?" They said yes, so we did.

For all that we really want to see the gear bugs fixed, I don't think people are abandoning Mosquitoes just yet.

[Skewgear]

I run one of them. Numbers are not down. In fact we're adding more Mossie slots because at peak times demand outstrips supply.

[Holbeach]

I've been asked to put a big "tick" on the final solution, but until "The Management" come up with a definitive answer to the strut question, I don't think there is one yet.

So far we have:

This is what we will do;

We might not do that,

We're doing stuff, so stop keep whining, (or words to that effect).

Nothing specific about the actual bug report. The animation and stiffness of the gear strut.

I've used every tool I can think of, to hammer this nail in, but I need an answer, in order to award that all important, big tick.

Thanks.

..

[Holbeach]

Sneaky devils!

They've fixed it and didn't tell anyone.

Perfect.

I tried my new Normandy map today and my first landing was at Biggin Hill.

That was easy I thought. I took a picture for posterity and noticed straight away it was sitting more level. (11.5).

Bugger me, the strut is at the correct length.

Time to see if this translates into better landings.

Sorted !!

 

 

.

[Slippa]

Hmmm.

Promising, though I’m a skeptical bugger .

I know what I’ll be flying later then and I don’t mind a bit. I’ve spent a while binding buttons and learning cold starts in jets and helis so it’ll be a break to go test flying. Hopefully . Would be chuffed if it’s better.

Due to ‘unforeseen circumstances’ someone in this thread succumbed to temptation last night after seeing some ‘suggestive pictures with RAF roundels on’ that may have been posted by someone else in this thread. Jester will have to wait in dispersal, I’ll have to check our Mossie out first .

Hope springs eternal eh? Fingers crossed. Cheers for the pointer.

 

[Holbeach]

Mosquito gear animation, updated by DCS..

 

Mosquito struts are back to normal, with ample movement and correct amount of static tube showing.

Biggin Hill and 50% fuel as in previous video.

A good result.. ..

 

 

..

Edited May 29, 2024 by Holbeach

[Art-J]

I praised beefed-up 2.9.5 tailwheel unit a bit too early perhaps. Just took the Mossie for a spin around Marianas and noted that Tinian International is still too bumpy for it and causes strut failures during taxiing and rollout. But then, it generally seems to be an airport with a rather rough mesh for DCS standards and it's not usual place to fly Mossie from so I guess I'll have to live with it for now and just operate from smoother strips.

I like non-documented revision of  main landing gear, however!

[Bozon]

23 hours ago, Holbeach said:

Sneaky devils!

They've fixed it and didn't tell anyone.

Perfect.

I tried my new Normandy map today and my first landing was at Biggin Hill.

That was easy I thought. I took a picture for posterity and noticed straight away it was sitting more level. (11.5).

Bugger me, the strut is at the correct length.

Time to see if this translates into better landings.

Sorted !!

 

 

.

A sneaky ninja update?

ED, why not putting this into the update notes and score some positive PR points? 

I will test this tonight for sure.

[Holbeach]

13 hours ago, Art-J said:

I praised beefed-up 2.9.5 tailwheel unit a bit too early perhaps. Just took the Mossie for a spin around Marianas and noted that Tinian International is still too bumpy for it and causes strut failures during taxiing and rollout. But then, it generally seems to be an airport with a rather rough mesh for DCS standards and it's not usual place to fly Mossie from so I guess I'll have to live with it for now and just operate from smoother strips.

I like non-documented revision of  main landing gear, however!

Tailwheel hasn't been touched, it still does a Jig down the runway, but I believe it's being looked at.

I've had a go at Eastchurch and here atTinian.

All good so far.

 

Next it's time to up the pucker factor and try out my new Normandy map, with some grass from my native Sussex. Friston and Deanland.

 

..

[BIGNEWY]

Tail wheel is a different issue and reported. 

Thank you for the feedback on the gear struts, happy to see it resolved.