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Landing touch-down pitch up moment is too great.


Terry Dactil

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The preferred method for landing tail wheel aircraft is often tail up, main wheels only.

Like this ...

However, this is impossible to do with the DCS Mosquito at present as no matter how little the vertical velocity is on touchdown there is a huge nose up pitch moment that cannot be counteracted.

It seems that the full aircraft weight is being applied immediately at touchdown instead of ramping up slowly as weight is gradually transferred onto the wheels.

I have flown many tailwheel aircraft in real life and all that is required is a minimum sink rate and to nudge the stick forward a bit when you feel the wheels touch.

I would love to be able to do the same here.

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I just did some circuits and concur, it is not possible to wheel land the Mossie. It seems like the suspension is too bouncy like it used to be on the P-47 before it was fixed. 

 

The tail will come up at around 90-100mph on takeoff, so to make a wheel landing you must touch down with higher speed, maybe around 120mph. Full flaps, pitch trim 2 notches nose down, touching down at -50ft/min, the impact on the mains forces the tail down. With the sudden increase in AoA and having touched down at a higher speed, you're now forced back up into the air, stall out, and plop down on all threes. Attempting to apply more forward stick on touchdown results in a high bounce without the increased AoA and results in a similarly nasty landing.


Edited by Nealius
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I just want to say, landing like this wasn't the norm back in the 1940s. They were taught to do a three point landing into wind.

 

Watch this video from about 10:50... He alludes to why they wheel it. 

 

 

To be honest watch it all, great clip. 

 

Also if you look at the notes the landing gear system is an area that they are working on, it is quite different to other aircraft we have so far. 


Edited by Krupi
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Windows 10 Pro | ASUS RANGER VIII | i5 6600K @ 4.6GHz| MSI RTX 2060 SUPER | 32GB RAM | Corsair H100i | Corsair Carbide 540 | HP Reverb G2 | MFG crosswind Pedals | Custom Spitfire Cockpit

Project IX Cockpit

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Here you go... Wasn't in the notes it was in the news segment. 

 

"Phase 2 features we are working on:

  • Operator's AI for multi-crew

  • Tire and shock absorber dynamics

  • Operable drift recorder device

  • Engine failures

  • Fire-extinguishers

  • Rockets armament

  • More liveries" 

https://www.digitalcombatsimulator.com/en/news/2021-09-17/


Edited by Krupi
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Windows 10 Pro | ASUS RANGER VIII | i5 6600K @ 4.6GHz| MSI RTX 2060 SUPER | 32GB RAM | Corsair H100i | Corsair Carbide 540 | HP Reverb G2 | MFG crosswind Pedals | Custom Spitfire Cockpit

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General technic is the same as usual:

 

Approach at 120mph or above

maintain 110/120 mph with a bit of engine

trim down

at touch down 100/110 mph push a bit forward.

 

Compare with a real thing is useless we are in a game and aeroligy is not implemented at all.

 

With more practice you will be able to do it,and stop to wait for a patch or something like that ,which give you ability,

Do it yourself.

Before waiting for a shock absorber patch we need a lot of priority fixes more importants.

 

Good game:)

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2 hours ago, cromhunt said:

at touch down 100/110 mph push a bit forward.

 

This isn't currently possible, as the tail will only come up at 100mph with forward stick. If you touch down at 100mph the tail will not produce enough lift to stay up, as you will be rapidly decelerating. 

 

After 10 attempts, there's a combination of sever tail-down moment and overreaction of the struts. Touchdown average 90-110mph, vertical velocity average -100fpm; softest -60fpm. That's 10~20 inches per second which is practically nothing. Three-point landings tend to bounce more than in other warbirds as well. The tail I could only keep up below 100mph if I kept power on for touch and goes. Landing at idle or near idle and the tail wouldn't stay up until I applied power and gained speed. With stick well forward and two notches nose down trim.

 

Like Krupi mentioned, the strut physics are probably WIP. Same thing happened with the Tbolt:

 

 


Edited by Nealius
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Between 100 to 110 i said and it's not mandatory just have you to adapt from circomstancies.

You forgotten the bit of engine/throttle to maintain level of flight:)

Even if you are playing on a computer the things in simulator are not also systemics than you are thinking.

We have to thanks the autors/devs who made something a little bit random.

 

I did something like that below after 30 minutes of training:

Players are always requesting something more real.

OK?:)

In real flight nothing is written definitly.With that in your mind maybe you could be understanding what is fly .

And if the devs trying to make the same feeling as real flight don't be surprised if it's a little bit difficult.

Practice is your friend😉

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1 hour ago, cromhunt said:

You forgotten the bit of engine/throttle to maintain level of flight:)

 

After two hours I finally got it thanks to this, plus one other thing I figured out: If I wait for the gear to touch, I will have a severe bounce no matter how gentle my touchdown. If I settle just above the runway then shove my stick forward to forcefully plant the gear, I won't bounce and I can keep the tail up. 

 

My approaches are always too high, so I floated halfway down Manston before saying "f**k it" and pushed the stick forward. 

 

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7 hours ago, Nealius said:

If I settle just above the runway then shove my stick forward to forcefully plant the gear, I won't bounce and I can keep the tail up.

Yep, that's actually how you make a wheeler, so fix that in you mind. Have a go with some other warbird if you have any, or TF at least, you'll see.

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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8 hours ago, Nealius said:

 If I settle just above the runway then shove my stick forward to forcefully plant the gear, I won't bounce and I can keep the tail up. 

1 hour ago, Ala13_ManOWar said:

Yep, that's actually how you make a wheeler, so fix that in you mind.

 

No it's not!

In real life doing that will kill you.

You fly the aircraft smoothly onto the runway; you don't just dump it there.

(I have 1000+ hours in taildraggerrs from Pawnees to DC-3s so I do know a bit about how it is done).

This is supposed to be an accurate simulation, not a cheap arcade game.


Edited by Terry Dactil
Getting grumpy
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2 hours ago, Ala13_ManOWar said:

Yep, that's actually how you make a wheeler

Not in the Spitfire. You need neither power on nor stick forward. I get stable wheelers with stick almost neutral, and a buttery smooth touchdown with little to no bounce. I don’t have to force her down onto the runway like the Mossie, which seems very suspect from a safety standpoint as Terry mentioned. 

 

Point is, the aircraft should not be launching itself back into the air after touchdown with a -50fpm descent rate. 


Edited by Nealius
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🤣🤣🤣🤣🤣

 

Yeah mates, whatever. I suppose all my taildragger pilot friends are alive just by chance, and myself I guess since every tail dragger I've flown in was landed like that as the book says. But you know better 😉.

 

S!


Edited by Ala13_ManOWar

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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Track with four touch-and-go's and a full-stop. Two of the touch-and-go's were trash, two plus the full stop were smooth as silk yet still had a bounciness and tail drop that felt excessive. It's like the oleo strut is animated, but doesn't actually absorb any impact. In this video, my first touchdown was at -17ft/m or -24ft/m according to Tacview, and still bounced. My second touchdown was at -30ft/m according to Tacview, and caused a large bounce. Touchdown speed was around 85~88kts.

 

 


Edited by Nealius
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The problem we have is that the pitch-up moment should be proportional to the sink rate on touchdown.

Take the extreme limit case where you are such an ace pilot that you have reduced the sink rate to zero just as the wheels touch.

  • The aircraft is still flying with the lift supporting all the weight,
  • As there is no weight on the wheels there can be no vertical reaction force from the ground, so there cannot be any pitch up moment. .
  • In fact, there should even be a slight pitch down moment from the drag on the wheels required to overcome the inertia of the wheels spinning up.
  • As the the aircraft slows weight settles onto the wheels  the pitch up moment should increase gradually in response to the oleo compression parameter.

It appears that we are getting the full pitch up moment as soon as the wheels touch.

3 point landings are no problem at all, but wheelers are bloody difficult and they shouldn't be.

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Found this on learning to do wheel landings...

Note

  • The stick is moved forward after touchdown; you don't need to stuff the aircraft down onto the runway as some people suggest.
  • Extra speed on the approach for better control of gusts, wind shear, crosswinds, and better visibility in single engine types

 

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1 hour ago, Terry Dactil said:

The problem we have is that the pitch-up moment should be proportional to the sink rate on touchdown.

 

Having zero experience with real life tail draggers, I can say this is precisely how it feels in the sim. no matter how well I can grease the tires, it still bounces/pitches up disproportionately. Neither the Spit nor Anton exhibit this behavior with wheel landings. 

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  • 2 weeks later...
  • ED Team
On 10/6/2021 at 9:56 AM, Terry Dactil said:

The problem we have is that the pitch-up moment should be proportional to the sink rate on touchdown.

Take the extreme limit case where you are such an ace pilot that you have reduced the sink rate to zero just as the wheels touch.

  • The aircraft is still flying with the lift supporting all the weight,
  • As there is no weight on the wheels there can be no vertical reaction force from the ground, so there cannot be any pitch up moment. .
  • In fact, there should even be a slight pitch down moment from the drag on the wheels required to overcome the inertia of the wheels spinning up.
  • As the the aircraft slows weight settles onto the wheels  the pitch up moment should increase gradually in response to the oleo compression parameter.

It appears that we are getting the full pitch up moment as soon as the wheels touch.

3 point landings are no problem at all, but wheelers are bloody difficult and they shouldn't be.

And there is the last but not the least factor - aircraft mass. As usually nobody thinks about it, they try to land the plane with default ME weight, full fuel and ammo.
But the higher is the mass the lower must be vertical speed at touchdown.
Generally, even for WWII planes, landings were with low fuel. Modern variants of WWII planes are way lighter, so 2 wheels landing is easier.
And, by the way, at least for German fighters during WWII, 2-wheels landing caused ***** from the squadron leader. 🙂 As unsafe.

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Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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  • ED Team
1 hour ago, Yo-Yo said:

they try to land the plane with default ME weight, full fuel and ammo

Just as a small note to this, default fuel in the ME is:
image.png

That said, this is why its important to include all details, we shouldn't assume your weight, but if given nothing we can't assume anything but default loads. (also note that on the landing practice mission, this is the weight as well.

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  • ED Team

It is full MAIN fuel that I meant.

 

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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