Structural Failure

[MiloMorai]

What flying testing was done before the modules are released to the public?

[philstyle]

I have one main question (split into two parts) at the moment about the wings failing.

 

Is the wing-failure primarily determined by how much "G" force it can take, and if YES, why is the pilot not affected by the G-force?

In Hiromachi's videos there is no indication of a blackout (indicative of high G) yet the snaps wing loose... I have also noticed this. Do the wings (at almost the same point on the longitudinal axis as the pilot) experience vastly different G than the pilot in a pitching maneuver?

Edited January 19, 2017 by philstyle

[Whisper]

For me, the most important point to clear up first would be to be sure and confirmed if the stick forces are currecntly properly simulated in the Spit or not, tbh. That would be a very first step toward clearing the issue.

I don't think there's been any acknowledgement or refutal on the fact there's currently no stickforce simulated.

[Hiromachi]

I'm no specialist, for the first question I'd say Yes. In regard to pilot, he is affected but it seems in rapid pulls the effects become apparent only after some time. I'm not entirely convinced this should be the case.

Again, I bring P-51D Galloping Ghost accident at Reno where the vertical acceleration peaked at 17.3 G. The characteristics of the airplane’s pitch changes during the upset were such that the pilot’s time of useful consciousness was likely less than 1 second.

Here in Spitfire pilot exceeds 10 G yet remains conscious and able to break wings.

[rel4y]

The brain has an oxygen reserve of ~4-6 seconds. So in the first seconds you can take a very high G load and wont black out. Afterwards there should be a rather rapid onset of the GLOC.

 

For slow onset Gs cardiovascular reflexes increase G tolerance by about 1 G, but only after more than 10 seconds.

[philstyle]

The brain has an oxygen reserve of ~4-6 seconds. So in the first seconds you can take a very high G load and wont black out. Afterwards there should be a rather rapid onset of the GLOC.

 

Yes, of course.. I forgot about that. That certainly explains why a structural failure could occur before a pilot blackout.

[Krupi]

It does appear that the spitfires manouverability is a double edged sword of sorts.

 

We simply don't have the feeling of dread that stopped pilots in any aircraft from going right up to the limit

[HeadHunter52]

So, there is agreement that the wing strength is fine, and that the real problem is not sensing Gs properly (cuz we ain't really flying)?

[Whisper]

So, there is agreement that the wing strength is fine, and that the real problem is not sensing Gs properly (cuz we ain't really flying)?

 

Or that stick forces are not properly rendered

[HeadHunter52]

Or that stick forces are not properly rendered

 

Might be. I pulled wings off at mid point (both at the same time) in a liesurely fight last night, twice. Never blacked out, and I used the heavy breathing as an indicator of stress amount and duration.

 

I don't know what to think at this point. It got to where I pulled the P-51 out of the hanger for the first time since October, and killed a few AI.

[philstyle]

So, there is agreement that the wing strength is fine, and that the real problem is not sensing Gs properly (cuz we ain't really flying)?

 

Dietrich, over on the Storm of War website, has done some analysis of one of Hiromachi's videos to calculate the likely G and it seems that the structural failure occurred in the 11-13G range.

 

See here: http://stormofwar.org/phpBB3/viewtopic.php?f=36&t=5934#p45431

 

So yes, it would seem that "visually" (plus some math) the wing-breaking is occurring at a sensible loaidng.

[Art-J]

Failure treshold is modelled correctly then. However, putting the elevator forces simulation aside for a minute, one has to ask the question - what can be done to provide the G-limit information to the player? Realistic blackout doesn't help - if the note about a couple of seconds oxygen supply for pilot's brain is correct, it would mean the short period G-resistance was comparable or could exceed structural limits of an airplane.

 

Should we, for example, go for a realism-compromise solution then, with linear blackout appearing smoothly earlier than it probably should, just to warn the player that he is closing to the 10-11 G figure?

[Krupi]

Thanks for the link, it ties up well with what Yo-Yo stated.

 

After seeing the video showing the aircraft going above 10G I have adjusted my diving to be gently when above 400mph.

 

Interestingly there is a chapter from Jeffrey Quil "Spitfire a test pilots story" where he goes into a detailed discussion about the elevators and stability he had an accelerometer in his aircraft and would routinely take the spitfires to 7-8 g at 480 mph

 

I will post the chapter here later today, they used a Bob weight at first to stop the elevator movement at higher g and then replaced it with the change to the elevators horn balance.

 

From this paragraph I now believe that the stick forces are not fully implemented at present.

Edited January 23, 2017 by Krupi

[Hiromachi]

Should we, for example, go for a realism-compromise solution then, with linear blackout appearing smoothly earlier than it probably should, just to warn the player that he is closing to the 10-11 G figure?

 

All of this will be a part-solution. About as much as using mild curvature on joystick. The only way to actually "feel" the thing would be if one would use similar size joystick with similar range of movement as in real one.

 

That is real issue for so many flight sim pilots, regardless of price of stick, without extension you have to work your way around to try to match real thing.

[Krupi]

All of this will be a part-solution. About as much as using mild curvature on joystick. The only way to actually "feel" the thing would be if one would use similar size joystick with similar range of movement as in real one.

 

That is real issue for so many flight sim pilots, regardless of price of stick, without extension you have to work your way around to try to match real thing.

 

+1 the spitfires control column is ~1 meter long and moves 11° forward and aft :joystick:

[Tomsk]

That is real issue for so many flight sim pilots, regardless of price of stick, without extension you have to work your way around to try to match real thing.

 

Very much true, a sim is never going to feel like the real thing. So the question is how can we make the sim to behave in a similar way. Clearly going into a 400mph dive, gently pulling on the stick and shearing the wings clean off isn't a sensible way for the sim to behave.

 

Perhaps it's possible that in a real spitfire you could pull hard enough on the real stick to rip the wings off before you blacked out ... but it seems pretty unlikely. It's also not something you could do by accident or just by being slightly ham fisted ... so it should be the same in the sim.

 

I would suggest that the stick force modelling is not yet implemented. Because being able to pull 11Gs in an instant and shear the wings off is probably something a human pilot simply would not be able to do ... and it's definitely not something they'd ever try to do. There's no doubt in my mind, the current behaviour is wrong however you look at it. Which isn't at all surprising given the Spitfire is a Beta release :)

Edited January 23, 2017 by Tomsk

[Hiromachi]

The real life combat is not limited by structural integrity of an aircraft but pilots ability to withstand loads. All those ultimate G-load factors were way beyond pilots body capability to withstand them, especially during combat where your body is experiencing constant acceleration and deceleration - one simply gets tired.

We dont get really tired since no desk can pull G's.

 

Yet virtual pilots break their wings since the early days of virtual aviation. Realism in virtual environment simply has its limits.

 

I believe that for the most the only solution for now is proper curvature and a decent stick. Maybe Yo-yo could add something on current status of implementation of stick forces.

[Combat Wombat]

In this book Which is a great read btw He talks about a time when all the Typhoon's in his Squadron were destroyed or out of service So they were issued with Spitfires for the time being ! On his first flight he was so used to manhandling the Typhoon around having to use massive amounts of input at times He pull both wings right off his spitfire without blacking out !!

https://www.amazon.com/Soldier-Cockpit-Typhoons-Stackpole-Military/dp/0811733688

[Krupi]

Wow

https://books.google.co.uk/books?id=AKIG14mPb0AC&pg=PT183&lpg=PT183&dq=spitfire+A+Soldier+in+the+Cockpit:+From+Rifles+to+Typhoons+in+WWII&source=bl&ots=-uC0MHWgpG&sig=WyPikMKoGtszJasc1d1g1S9PH-8&hl=en&sa=X&ved=0ahUKEwix87KBz9rRAhXI8ywKHWDkBx4Q6AEIGjAA#v=onepage&q=Spitfire%20tore&f=false

 

You really have to re learn how to fly in the spitfire, incredibly manoeuvrable but you have to be gentle!

 

Thanks for sharing + rep!

[Combat Wombat]

Wow

https://books.google.co.uk/books?id=AKIG14mPb0AC&pg=PT183&lpg=PT183&dq=spitfire+A+Soldier+in+the+Cockpit:+From+Rifles+to+Typhoons+in+WWII&source=bl&ots=-uC0MHWgpG&sig=WyPikMKoGtszJasc1d1g1S9PH-8&hl=en&sa=X&ved=0ahUKEwix87KBz9rRAhXI8ywKHWDkBx4Q6AEIGjAA#v=onepage&q=Spitfire%20tore&f=false

 

You really have to re learn how to fly in the spitfire, incredibly manoeuvrable but you have to be gentle!

 

Thanks for sharing + rep!

 

Thankyou :smilewink:

[Pocket Sized]

https://forums.eagle.ru/showpost.php?p=3064495&postcount=3

[NineLine]

Just a simple question, do any of you have your G Simulation set to anything other than Simulation in the sim? Under gameplay options?