Strange tendency to prop strike after latest patch ?

[Anatoli-Kagari9]

Crumpp complained about something weird with the pitch behavior of the Fw190, now it's me, who killed 4 props today at the AGS server while just trying to taxi and as the canopy is closed.

 

I noticed latter that my pitch trim was almost fully forward, while during engine start it was correctly placed. Apparently this happens when the canopy starts to close, and even made me believe we now had a bug with an extra-heavy canopy...

 

Tried a quick mission and didn't find that same effect, but the nose does feel heavier, and some sort of pitching down moment is noticeable during the takeoff run ?

 

Any of you noticed the same ?

[Captain Orso]

First off, I can't say I've noticed any difference between 1.2, 1.5 and 2.0 with regards to take off and landing.

 

What I don't understand a couple of things from your post. How do you kill a prop while taxiing? Unless you hit the breaks hard and nose-over, how is the prop going to touch the ground?

 

I noticed latter that my pitch trim was almost fully forward

My stupid comment would be, well then don't trim the nose down .... :huh:

 

Without more clarification, you seem to be insinuating that the nose-trim-wheel is moving forward all the way by itself.

 

Apparently this happens when the canopy starts to close, and even made me believe we now had a bug with an extra-heavy canopy...

I don't understand. Does the nose seem heavy to you from the way the aircraft is handling? or is the nose-trim moving when you close the canopy? Are you closing the canopy while taking off? How else would you notice the aircraft becoming nose-heavy while closing the canopy, because while sitting with all 3 wheels on the ground, unless you're doing ground-loops, there's no way to tell how much weight is anywhere on the aircraft--which tanks are full or empty (wing tanks?), how much ammo (bombs and rockets) are loaded, nor how anything is trimmed, which has no affect what so ever until the aircraft has reach flight speed.

[Anatoli-Kagari9]

[...]

 

 

I'll have to test further, but I found that in the online mission I experienced that problem whenever I started taxiing and the canopy was closing, without touching anything ( and I know I have my axis and buttons all properly set ! ) the pitch trim wheel stepped all the way forward.

 

A slight increase of throttle will then cause a prop strike.

 

When it first started happening yesterday, after the latest patch, I was first tempted to believe there was some bug, causing the weight of the canopy to shift drastically the CoG, because the prop strike caused by the nose pitching down without any input, happened only when the canopy started to close. Also I knew, from my taxi checklist, that all of the trims had been properly set, so...

 

But at the 4th time it occurred I started searching for the reason more carefully, and it was only at that moment that I saw the pitch trim wheel suddenly moving fast fwd to the max nose heavy position...

 

I have tried takeoffs in single player mode, both in 1.5.1 and in 2.0 Alpha NTTR and there is no such weird behavior.

 

So, I'm not insinuating anything, just pointing out what seems to be a problem with a specific online mission scenario ? Or maybe something else ?

[Captain Orso]

I'll have to test further, but I found that in the online mission I experienced that problem whenever I started taxiing and the canopy was closing, without touching anything ( and I know I have my axis and buttons all properly set ! ) the pitch trim wheel stepped all the way forward.

 

Can you see it actually moving? What if you set it back to neutral?

 

A slight increase of throttle will then cause a prop strike.

 

So with a slight increase in throttle you start nosing over?

 

I'll try setting nose-trim all the way forward manually and then see how much throttle I have to push before the tail starts to lift, but I expect the tail only to start to lift once I've gotten up enough speed.

 

When it first started happening yesterday, after the latest patch, I was first tempted to believe there was some bug, causing the weight of the canopy to shift drastically the CoG, because the prop strike caused by the nose pitching down without any input, happened only when the canopy started to close. Also I knew, from my taxi checklist, that all of the trims had been properly set, so...

 

Try watching the nose-trim-wheel while closing the canopy and see if it's moving. It's got to be happening at some point in time.

 

But at the 4th time it occurred I started searching for the reason more carefully, and it was only at that moment that I saw the pitch trim wheel suddenly moving fast fwd to the max nose heavy position...

 

Huh? What? When did you see it moving? What were you doing at the time?

 

I have tried takeoffs in single player mode, both in 1.5.1 and in 2.0 Alpha NTTR and there is no such weird behavior.

 

My experience too.

 

So, I'm not insinuating anything, just pointing out what seems to be a problem with a specific online mission scenario ? Or maybe something else ?

 

Well, you said that the nose-trim was adjusted all the way to fully nose-heavy without your having done the adjustment yourself. The only logical conclusion is that either it's happening by itself, or that you are doing it inadvertently.

[Solty]

I just flew in MP. No problems on my end. Smooth take off and easy to fly plane.

[Crumpp]

Jcomm,

 

I had a similar experience online when my elevator trim suddenly went full tilt nose down as well.

 

I was in flight when it happened. I have been having some controller issues for the last week or so.

[Crumpp]

Crumpp complained about something weird with the pitch behavior of the Fw190,

 

Maybe I jinx'd you.....

[Anatoli-Kagari9]

Maybe I jinx'd you.....

 

Tonight, if I get the time slot at the home PC, I'll try to fly at another server, and then back at the same where it happened, and will report back the results

[Anatoli-Kagari9]

Ok,

 

follow up to this strange problem that was always happening when picking the Mustang at the BURNING SKIES Mission Alpha server / mission (DCS 1.5.1 )...

 

I set the fuel level to 58% and asked for auto-start ( RWIN HOME )

 

As the engine started ( with my help from priming and mixture ) and I started taxxing, the nose dipped and I always had a tail strike...

 

I believe this was fixed by yesterday's patch, although apparently it was **only** an updater patch ?

 

Truth is it doesn't happen today - the autostart sequence was applying 2 º nose down at the end of the startup which coincided with me starting to taxi. Today I can taxi perfectly without experiencing this.

 

Could this also be related with what Crumpp and other have reported regarding an apparent different feel ( lighter / changed pitch response ) of the P51d when flying online ????

 

Anyway, all is OK now !

Edited December 6, 2015 by jcomm

[Anatoli-Kagari9]

Well....

 

after all the problem persists :-(

 

At the Online BURNING SKIES Mission Alpha, using 58% fuel and 100% amno, autostart ( RWIN HOME) as I start taxiing and 2º nose down pitch are applied the nose deeps and a tail strike results :-/

 

My positive test was done with 100% fuel...

[OutOnTheOP]

Possibly related issue: I discovered that in an online server (I do not recall which), a "cold start" Bf109K4 spawned in with the landing gear button pressed in to "retract". Not a problem, unless you start the engine with the button still pushed in, but if you do, it'll pull in the gear and drop the aircraft on it's belly.

 

Similarly, the cold-start P-51D starts with battery and inverter turned on via the right side electrical panel, where it really should not. This one doesn't cause problems, but *does* further prove that the starting switch settings area not the same in 2.0 as in 1.5 or 1.2

[Echo38]

My stupid comment would be, well then don't trim the nose down

 

I would think that, at taxiing speeds, trim shouldn't make a noticeable difference, even with a burst of propwash over the tail. It's possible that there is more than one issue here.

[Anatoli-Kagari9]

I would think that, at taxiing speeds, trim shouldn't make a noticeable difference, even with a burst of propwash over the tail. It's possible that there is more than one issue here.

 

Please notice that I'm not the "trimmer agent" on this event :-) - it's done automatically when you press RWIN-HOME for "START Cheat"...

 

Of course since most of the time I start my taxi asap, even before the auto startup process arrives the canopy close, followed by setting 2º nose heavy pitch trim, it happens when I am already rolling along the tarmac, and then, as the trim is applied, the aircraft noses down and a prop strike is the necessary outcome :-/

 

This is either related to some problem with online missions, or some modification to the flight dynamics, at least of the p51d, in terms of tail surface and or prop effects, CoG ? I don't know what is causing it, but it's there, and yesterday when it did not happen and I thought it was solved I then found that I was using 100% fuel ( hence full fuselage tank ) and the problem is only evident at 60- % fuel settings ( I usually set it at 58% for my missions online ).

 

Or, might it be due to any refinements in the turning performance of the Mustang, that some users are also noticing, and would result from flight dynamics changes ?

Edited December 7, 2015 by jcomm

[Captain Orso]

I would think that, at taxiing speeds, trim shouldn't make a noticeable difference, even with a burst of propwash over the tail. It's possible that there is more than one issue here.

 

I haven't tried it on the ground, but I did test it out in the air. You can trim the nose down so hard that with the stick pulled all the way back you cannot maintain level flight.

[Captain Orso]

Please notice that I'm not the "trimmer agent" on this event :-) - it's done automatically when you press RWIN-HOME for "START Cheat"...

 

Whaaaa? "START Cheat"??? Who does such things? :ermm:

 

I think over the last year I've only done it once or twice, just to see how it works.

 

Time you've learned to do it by the manual :pilotfly:

 

:smilewink:

 

Of course since most of the time I start my taxi asap, even before the auto startup process arrives the canopy close, followed by setting 2º nose heavy pitch trim, it happens when I am already rolling along the tarmac, and then, as the trim is applied, the aircraft noses down and a prop strike is the necessary outcome :-/

 

This is either related to some problem with online missions, or some modification to the flight dynamics, at least of the p51d, in terms of tail surface and or prop effects, CoG ? I don't know what is causing it, but it's there, and yesterday when it did not happen and I thought it was solved I then found that I was using 100% fuel ( hence full fuselage tank ) and the problem is only evident at 60- % fuel settings ( I usually set it at 58% for my missions online ).

 

Or, might it be due to any refinements in the turning performance of the Mustang, that some users are also noticing, and would result from flight dynamics changes ?

 

Seems it's a combination of impatience and ED not having kept the "START Cheat" up to date.

 

I could suggest a solution, but I wouldn't want to spoil your fun :music_whistling:

[Anatoli-Kagari9]

:-)

 

I know how to properly start any of the ww2 warbirds, as well as the uh-1h and even the mi-8, but I am usually in a rush when I start DCS because my flight simulation sessions never last long... so, I am an admirer of the start / shutdown cheats, as much ass I love the "E" key in IL-2 Battle of Stalingrad....

 

And, I don't think using the cheat should make any difference, unless the trim wheel get's turned more than it should for 2º nose down after one of the last updates....

 

Anyway, I'll try to make a manual start and trim it manually as well for takeoff and see what happens, but....

 

- I really don't know if a real p51d, even fully trimmed down, would prop strike at taxiing power settings when not even a burst of power is used ?

[Captain Orso]

8<

 

- I really don't know if a real p51d, even fully trimmed down, would prop strike at taxiing power settings when not even a burst of power is used ?

 

I've tried setting my trim to fully nose-heavy and trying to get the tail to lift off the ground. I can only get it to do so by hitting the breaks too hard, accelerating really hard, or picking up speed to where the trim starts to take affect, close to takeoff speed--or at least where aerodynamics start to take affect.

 

At taxiing speeds I'm on glued to the ground

[Echo38]

I haven't tried it on the ground, but I did test it out in the air.

 

That's a big difference, in flight vs. taxiing. Trim is effective at flight speeds. Trim is irrelevant, however, when airflow is very low, as when taxiing. Remember, in real life, all trim does is to reduce stick forces. There are no stick forces to speak of, when taxiing, even if you give a solid burst of power.

 

Edit: I wrote that before I saw your later posts. You seem to have come to the same conclusion within the sim.

Edited December 8, 2015 by Echo38

[Anatoli-Kagari9]

and it has always been like that for me too until the latest patch.