investigating New Landing Gear and Tires Problems

[stuart666]

2 hours ago, Art-J said:

Nah, both my tracks are recorded in OB after Tuesday patch.

The point I emphasized in my post is, after taxiing, you WILL roll fast at 3-point for a dozens of seconds during every takeoff and landing. So whether you want it or not, the tailwheel assembly will be cumulating damage. My fast taxiing was just simulating beginning of a takeoff roll, or standard roll-out after landing. The strut may or may not fail in a mission where you perform only one takeoff and landing in a row (depending on which map and airbase we're trying), but with more of these it will fail eventually and I'd hazard a guess Mossie maintenance technicians didn't have to fix or replace tailwheel units every 3 missions or so in real life  .

I specifically avoided rolling over grass-concrete boundary, as this one has been known for causing failures in previous DCS versions already, I also avoided grass strips in my tests, 'cause concrete / asphalt ones should in theory be smoother (?). Last but not least I avoided Marianas map, which also has some rough surface mesh issues at Anderson. Just chose stock mission at Kutaisi for this very reason, not getting beyond the runway.

The only grass strip takeoff and landing at Normandy I did once was at Detling and they went OK, but that's obviously not enough reference data. Your observations from other grassy airfield there are interesting, will try them when I have time.

 

It might, just might, be the difficulty in VR in determining how far from the ground you are, hence him landing a bit harder than I want. I dont know. I certainly can say that operating off dirt strips and runways, there is significant occelation, more than on concrete.

Anyway, please try it, Id be curious what others think. Im thinking its less the fault of the aircraft, than some maps modelling rough ground more aggressively, which is creating a problem with this aircraft. Just a personal observation.

[4eyes]

35 minutes ago, stuart666 said:

It might, just might, be the difficulty in VR in determining how far from the ground you are, hence him landing a bit harder than I want. I dont know. I certainly can say that operating off dirt strips and runways, there is significant occelation, more than on concrete.

Anyway, please try it, Id be curious what others think. Im thinking its less the fault of the aircraft, than some maps modelling rough ground more aggressively, which is creating a problem with this aircraft. Just a personal observation.

The most difficult airfield is Manston on Normandy Map. 

[stuart666]

Thanks, Ill try that.

[Slippa]

10 hours ago, Art-J said:

Nah, both my tracks are recorded in OB after Tuesday patch.

I couldn't load it today, something my end I think, must be, this is my first forray into the track system.

I've tried it out on the Channel map now as well as N2. I don't think it's the maps, it's the Mos. I can manage it but it isn't pretty and can spin out at lower speeds. thankfully It's fine in the air.

The thing is it's bouncing about like I'm trying to taxi over marbles before I've had any input, other than to roll it out. The tailwheel isn't breaking but I can't see the reasoning behind tinkering with it. I'm not keen at all as it is, I'm already choosing other birds to fly. Incidentally, the Spit and Pony are fine from the same fields.

Saved a little track, Not as bad now as I'm aware of it hopping about but still almost slid it into traffic. Hope it gets put back as it was, I can't see any sense in it as it is. Somebody took the wooden wonder for a little Christmas drinky and she's come home with perpetual hiccups.

MosOntheLashN2.trk

[4eyes]

I break the rear wheel almost every landing at Manston. On the Normandy Map.  Crossing the threshold 110-125 mph.  Dirt strips in Normandy, no problems. 

[stuart666]

9 hours ago, Slippa said:

I couldn't load it today, something my end I think, must be, this is my first forray into the track system.

I've tried it out on the Channel map now as well as N2. I don't think it's the maps, it's the Mos. I can manage it but it isn't pretty and can spin out at lower speeds. thankfully It's fine in the air.

The thing is it's bouncing about like I'm trying to taxi over marbles before I've had any input, other than to roll it out. The tailwheel isn't breaking but I can't see the reasoning behind tinkering with it. I'm not keen at all as it is, I'm already choosing other birds to fly. Incidentally, the Spit and Pony are fine from the same fields.

Saved a little track, Not as bad now as I'm aware of it hopping about but still almost slid it into traffic. Hope it gets put back as it was, I can't see any sense in it as it is. Somebody took the wooden wonder for a little Christmas drinky and she's come home with perpetual hiccups.

MosOntheLashN2.trk 6.37 MB · 0 downloads

But they havent modelled suspension yet. Thats why we need to evaluate this, which is basically the tech demonstrator, because all the others sooner or later are going to get the same tech. If you think the Mosquito is bad, just wait till they put it on the Me109K and the spitfire.

 

If you are spinning out at lower speeds, arguably thats modelling correctly. The Mosquito in real life suffered from exactly the same problem. The mosquito arguably SHOULD be a handful on the ground. Its just a question of how much is reasonable from what we know of how it peformed in that environment, compared to how its modelled. Considering that the surviving mosquito prototype cracked the fuselage twice in landing accidents, shows you this was not the cute and cuddily performer on the ground we have all gotten used to. On the ground it should be a bitch.

 

[Yo-Yo]

I have not Normandy map, just Dover and Caucasus and I have some questions to the surface noise we have now. New suspension model is much more accurate and, thus, more sensitive to the stimulus, and watching the tail wheel movement in details I can say that bumps seems to be like cobblestone road..

Dover map shows no significant issues for us. It was a fun testing it hardly :).
 

 

 

[Art-J]

20 hours ago, Yo-Yo said:

No, wheels do not cumulate damages.

OK, maybe it's semantics or language thing. What I meant is, in my 2nd replay track I got "Central / tail strut drive inoperable" event registered at 2:23 and the strut was still visually OK when looked outside. Two minutes and some extra bumps later, however, it half-collapsed.

Thanks for further testing and cool videos. I understand that tail strut sensitivity is greater and more accurate now, but that leaves us with a wider problem affecting both ED and 3rd party devs - how many airports on various maps should be tested and reworked with better surface mesh, when even some Caucasus runways can cause such tailwheel issues (as my Kutaisi test showed).

Edited December 22, 2023 by Art-J

[stuart666]

I think the tailwheel always has been a problem. I never had an issue with the tailwheel in the 109 or the Fw190, or the Spitfire. I sometimes broke the mosquito one even before this upgrade.

I think its a case of this upgrade has made breaking tailwheel is more likely. Why is that, I think is the bounce making the tail whip, which brings it up enough for the tailwheel to break. But I think its is perhaps only something lots of tracks can prove. I still think a lot of is people trying to taxi or fly it like they used to, and becoming surprised that taxing at 20mph is a bad idea.

I think personally this upgrade is a step in the right direction. There is probably some adjustment to be made, but whether that should be the bounce, at least on certain maps, or just making the tailwheel a bit more capable of standing up to abuse, im not quite certain. Perhaps a mix of the two.

Just now, Art-J said:

OK, maybe it's semantics or language thing. What I meant is, in my 2nd replay track I got "Central / tail strut drive inoperable" event registered at 2:23 and the strut was still visually OK when looked outside. Two minutes and some extra bumps later, however, it half-collapsed.

Thanks for further testing. I understand that tail strut sensitivity is greater and more accurate now, but that leaves us with a wider problem affecting both ED and 3rd party devs - how many airports on various maps should be tested and reworked with better surface mesh, when even some Caucasus runways can cause such tailwheel issues (as my Kutaisi test showed).

Well yes, you are right. They all are going to have to be tested presumably. If we could be certain everyone used the same mechanics as the ED maps it would be no problem, but it would seem some of them do appear rougher.

Probably ought to try the falklands, that might be interesting.

[Art-J]

Oh, don't get me wrong, I can see the new model is a big step in good direction. I like how both mains behave now, it makes takeoffs and landings more challenging and, looking at these real life vids, mains seem to be quite bouncy indeed.

It's just the tailwheel strut behaviour that raises some concerns for me. I'm sure further tweaks will come, but it becomes clear now that it's going to be a combined aircraft and map development problem. 

I only own Nevada, Channel and Normandy as payware maps, so my testing capabilities are limited.

Edited December 22, 2023 by Art-J

[Yo-Yo]

39 minutes ago, Art-J said:

Oh, don't get me wrong, I can see the new model is a big step in good direction. I like how both mains behave now, it makes takeoffs and landings more challenging and, looking at these real life vids, mains seem to be quite bouncy indeed.

It's just the tailwheel strut behaviour that raises some concerns for me. I'm sure further tweaks will come, but it becomes clear now that it's going to be a combined aircraft and map development problem. 

I only own Nevada, Channel and Normandy as payware maps, so my testing capabilities are limited.

 

To avoid differences between DCS versions (our trunk and release) could you test Channel map and airfields there? My tests were performed using Caucasus and Channel.

By the way, compare the Mosquito tail wheel with 10 cm tyre profile and the same rubber strut travel loaded with about 1000 kg and car suspension for 250-500 kg load

[Art-J]

OK, will probably be able to do more playing after Christmas, maybe other guys can help in the meantime as well.

If you did spend lot of time on Channel already, I think my tests would just be unnecessary duplication of yours because I would guess runways surface properties are the same in your internal DCS version and the public one (?). But sure, I'll try do do some more flying off grass and concrete strips when I can.

Channel versions of Detling and Manston seemed to be rather OK, although I only took off and landed on each of them once so far.

It all reminds me similar problems that race and rally sim developers face. No matter how good tyre and suspension simulation is, if there are problems with track surface mesh modelling the final effect shows unforseen issues.

Edited December 22, 2023 by Art-J

[Slippa]

Looking at it I’m asking myself what’s causing the jolt? Where’s the massive boulder or sleeping policeman? The tailwheel looks as if it’s being driven over cobbled stones. There aren’t any, so what physics are causing the vertical oscillation? I wouldn’t mind but the surface isn’t a rally track, especially Manston. It’s tarmac. I’m all for improvements in suspension or anything else but as it is you could taxi around an ice rink and still give yourself a headache from the vibrations.

I can’t make sense of it as it is.

[stuart666]

Just tried the Manston map on Normandy, and I agree its a bit bumpier than the one on Channel. Not much, but enough to perhaps make a difference. If you can land at say 100mph and plant a 3 pointer, you get away with it. But I just did a landing right now (I should have saved the track, sorry) that was just a little harder, and it bounced, slamming the tail down and pegging out the tailwheel. So yes, it does happen. I think tbh this always did happen if you landed a little rought, but it seems harder to land now, so people are noticing it more.

Gut instinct, Normandy runways are bumpier and rougher which compounds this problem. Broadly Channel are a bit smoother, so its a bit easier to pull off a decent landing.

32 minutes ago, Art-J said:

OK, will probably be able to do more playing after Christmas, maybe other guys can help in the meantime as well.

If you did spend lot of time on Channel already, I think my tests would just be unnecessary duplication of yours because I would guess runways surface properties are the same in your internal DCS version and the public one (?). But sure, I'll try do do some more flying off grass and concrete strips when I can.

Channel versions of Detling and Manston seemed to be rather OK, although I only took off and landed on each of them once so far.

It all reminds me similar problems that race and rally sim developers face. No matter how good tyre and suspension simulation is, if there are problems with track surface mesh modelling the final effect shows unforseen issues.

 

TBH, I probably spent more time on Normandy, looking to replicate what others have seen. Id personally welcome someone comparing it to channel as I did. All opinions are subjective, so Id appreciate my theory being tested out in comparing the two.

[Art-J]

Oh, youre right, there's definitely something to it (Normandy map I mean). As shown in my replay track No. 1, during takeoff attempt at Normandy Manston, while taxiing from the furthest western parking spot I got a "central / tail strut drive inoperable" failure already before I even started a takeoff roll  . Granted, that was a fast taxiing and lining up, but if it happened there and then, it would happen during takeoff roll anyway. Failure happened on the western light-grey section of the runway, but I don't know if that one has a different physical mesh compared to dark-grey section, or if it's only a different texture.

There was no such problem during Manston takeoff on Channel map.

Edited December 22, 2023 by Art-J

[stuart666]

Just tried landing at Mount pleasant in the falklands. Landing was ok, but I notice during fast taxiing on what is nominally a flat surface that the tail was porpoising a little. I can entirely see why fast taxining can cause damage. On psp plating or grass, yes thats justifiable. But you would think things ought to be a bit different on a concrete taxiway. Its almost like there is some kind of feedback loop on the tailwheel that causes bounce, even when there shouldnt be.

Ill try the grass strips here and see if anything else shakes loose.

[stuart666]

Funny thing, landed badly and bounced on Goose green, slammed the tail down. And... no broke tailwheel. I also had a noseover, something ive not done on the other airstrips. Weird....

Ok, second time I did bust it. But it seems somewhat harder to make it happen than the grass strips in Normandy.

Incidentally, dont try to land a mosquito at goose green. Its way too short...

Edited December 22, 2023 by stuart666

[stuart666]

Yeah, landed in a few airports in South Atlantic, broadly seems good. Ironically the surface being fairly good shows up the tailwheel bouncing quite a bit by itself. I think that probably ought to get looked at.

One thing I should add, I dont know how you land your mossies, but I find slightly nose up if not a three pointer is good, try and touch down about 100mph as the book says. If you control your rate of descent with the throttle you tend to get a much softer landing.

[Slippa]

Attached is a track. In it, I'm testing both the Mossie, radios, Mission Editor and track saving system.

At least, I was, until something happened that both confused then tickled me. I think I've blotted my copybook, though to be fair, I hadn't looked at it so no matter.

I'm on the Normandy map, at St. Pierre Du Mont. I roll off the apron onto the taxi-way and the shaking started, albeit minimally. I stopped and watched the ground vehicles I'd just placed to see how they behaved. (Badly). I pushed on to make my way to the runway when a popup in red told me a soldier had been killed. I'd no idea who by as I'd only plotted a couple of things and thought they'd be fine. I hadn't counted on Captain Psycho having a game of chicken starboard and definitely didn't have a chance of doing anything about it.

I wonder if the message I got telling me my whole record would be wiped holds up?

I've removed Captain Psycho from the mission and will continue my tests with the phantom fuselage frictions. This isn't what they mean by having a 'Frat party'.

Once the deed was done I carried on toward the runway. I'm on the verge so expect a little bumpiness but once I'm on the track the tailwheel starts doing it's exercises with little or no encouragement. Twitchy and bouncy.

 

MosTstFrat-How.trk

[zcrazyx]

Having flown light vintage tail draggers IRL, my two cents is that slow speed taxiing seems more bumpy then it should be, at least around needs oar point on the normandy 2.0 map. I would expect bouncyness at higher speeds from the rear end but not while slower. Another reason it may seem more bouncy then it should be is because IRL our heads self filter our vision much in the same way a camera has a stabelisation mode. 

Edited December 26, 2023 by zcrazyx

[Tea-Pig]

I hadn't flown the Mosquito for a while until yesterday and initially forgetting about the new suspension upgrade I felt it was much bouncier and harder to keep straight than I remembered. I have a motion chair rig and it really bumps about while taxiing, even very slowly. I broke the tail wheel several times just taxing at walking pace round the tight bends to the runway on the Normandy hot start instant action. The tailwheel also breaks extremely easily on landing. It's like it's made of glass. 

I've attached a short track of the Take-off Practice instant action at Manston on the Channel map. The landing is the interesting bit. It's certainly not one to be proud off as I flared too high but the touchdown was at least a three pointer. Notice the huge puff of smoke from the tailwheel but not the mains. Also notice that the tailwheel seems to survive the dodgy touchdown and the subsequent bounces but then fails in several stages during the rollout which gets progressively bouncier as the plane slows down. I didn't touch the brakes during the rollout.

I can't comment on the historical accuracy of this but I find it hard to believe that the real thing was so fragile.

tail wheel.trk

[NineLine]

12 hours ago, Tea-Pig said:

I hadn't flown the Mosquito for a while until yesterday and initially forgetting about the new suspension upgrade I felt it was much bouncier and harder to keep straight than I remembered. I have a motion chair rig and it really bumps about while taxiing, even very slowly. I broke the tail wheel several times just taxing at walking pace round the tight bends to the runway on the Normandy hot start instant action. The tailwheel also breaks extremely easily on landing. It's like it's made of glass. 

I've attached a short track of the Take-off Practice instant action at Manston on the Channel map. The landing is the interesting bit. It's certainly not one to be proud off as I flared too high but the touchdown was at least a three pointer. Notice the huge puff of smoke from the tailwheel but not the mains. Also notice that the tailwheel seems to survive the dodgy touchdown and the subsequent bounces but then fails in several stages during the rollout which gets progressively bouncier as the plane slows down. I didn't touch the brakes during the rollout.

I can't comment on the historical accuracy of this but I find it hard to believe that the real thing was so fragile.

tail wheel.trk 6.26 MB · 0 downloads

Interesting, I saw what you were probably talking about that seemed to damage the tail wheel after landing (although I am sure some of that damage was incurred during landing).

If I take control of the track at this point it smooths out... which is odd as well.
 

 

 

On 12/19/2023 at 7:10 PM, 4eyes said:

When landing, the Mosquito's tires sink into the ground.  

 

 

Just to answer the original post, flat tires are still represented like this. The animation for flat tires is still a work in progress. This is the same as before the update. Thanks. 

[Tea-Pig]

7 hours ago, NineLine said:

Interesting, I saw what you were probably talking about that seemed to damage the tail wheel after landing (although I am sure some of that damage was incurred during landing).

 

If I take control of the track at this point it smooths out... which is odd as well.
 

 

 

 

Just to answer the original post, flat tires are still represented like this. The animation for flat tires is still a work in progress. This is the same as before the update. Thanks. 

There's clearly something gone a bit wonky with the track in the first video. It looks bouncy but credible on my computer.

I don't know how to bring up that status panel in your videos, but I did notice that if I abort the replay immediately after touchdown the debrief says the central strut is damaged, and I would say that's credible given that the landing was far from perfect, but the subsequent collapse while rolling out seems a bit off and mirrors other taxiing incidents I have noticed. I will see if I can replicate and get a track for the slow speed collapses I had on the Normandy map.

[Art-J]

^ Nineline has access to extra damage assesment tool in their internal game build, that's where this panel window comes from.

It seems tail unit damage has two separate phases: 

1) an audible loud metal thud (with corresponding strut inop event registering in post-mission briefing), but with strut still seemingly more or less functional and visually OK in external view;

2) strut collapse (half-way at first, progressing to complete, some bumps & bounces later).

Didn't have time for playing much through Christmas break unfortunately so haven't tried many airfields. Checking the Normandy 2 hot start missions at Vilalcoublay and West Malling, these runways appear to be OK, ie. bumpy, but not to the point of causing strut damage.

[Night Owl]

@Yo-Yo

You can also check out this thread in CB forum, there I was using Syria map and it very clearly shows an exaggerated, self-propagating bouncing of the tail wheel. Also included a real life video as an example. 

It's unlikely to be a map issue. 

 

Edited December 29, 2023 by Night Owl