Elevator damage not detected by aircraft systems?

[Worrazen]

Not sure if this is for proper bug report, it may be known because it's early access and just not done yet, but some of the AAA Zu23 shot my right elevator off, it wasn't moving, but the airplace FCS reported zero problems and all of the numbers were moving normally as if nothing happened, but again, the thing was 95% missing and was not moving up or down, it was still, whatever was left of it. The left elevator had bullet hole marks but was working normally.

 

There were no cautions, no advisories, nothing.

 

Unfortunately I crashed it due to my lack of focus (late at night) just before landing, I wanted to do a FCS bit test and other stuff to make something show up.

[unknown]

Question - FM behavior after battle damage

 

Hi @ll,

i have a quick question about the FM after i got hit by 23mm shells that ripped off my right Elevator. I would have thought that the FA-18(or every aircraft with that layout) would roll to the right because the "lift surface" on the right side is smaller now. But my FA-18 was rolling to the left. :suspect:

Do i have a mistake here in my thinking? Is this a bug?

 

Edit: I run the latest DCS OpenBeta version.

[Flamin_Squirrel]

The damage model is work in progress I believe.

 

Don't expect warnings to be foolproof even when it's complete though. Remember that the FCS monitors the performance of the control system, not the structural integrity of the control surfaces themselves.

[David OC]

The FCS is still possibly pulling up to hold 1G flight.

 

Example: To go up the air pushes down on the elevator(s) deflecting the tail down.

 

In this case it's pushing down on only the left elevator causing you to roll to the left.

 

[unknown]

Hm, that could be an explanation. But why does it want to roll to the left if i roll left/right or pitch up/down? My brain has problems to understand that. :D But thank you for your help. :thumbup:

[macedk]

Also I don't think BD is done yet ..by far

[Sabadin]

If the airfoil on the horizontal stabilizers is like most traditional ones, they actually generate a downward force, so losing the right stabilizer would result in the left stabilizer generating an unopposed downward force on the left side. Sorry I'm on mobile so can't really throw together a good diagram

[NineLine]

This is correct and an aspect of an FBW system in which the FCS will use other control surfaces to compensate.

 

There was one Hornet pilot that lost a vertical stab but did not realize until after he landed.

[Vilab]

unless you pull quite high AoA ( which i don t think you can with only 1 elevator left ), the F-18 is still stable, that means the center of lift/drag is behind the center of mass, so the elevator Always need to build some downforce to keep the nose up.

 

if you pull the stick, the elevator will build more downforce ==> roll to the left, if you pusch it it will build upforce ==> roll to the right

 

 

if the FCS would actually play its role, the plane would not be rolling to the left, or to the right at all when pulling/pusching the stick ==> the pilot would not notice the loss of the elevator ( if that story is truly true, and if the F-18 FCS actively try to keep the plane at 0°/s in roll even when building Gs with assymetric load for eg )

 

if the F-18 FCS works the way you describe NineLine, that means ED forgot a few thing in the way they modeled the FCS

Edited October 2, 2018 by Vilab

[Worrazen]

The damage model is work in progress I believe.

 

Don't expect warnings to be foolproof even when it's complete though. Remember that the FCS monitors the performance of the control system, not the structural integrity of the control surfaces themselves.

 

Understood, indeed about the integrity. I was thinking some other caution

 

I was under the impression maybe some kind of system that would detect "unexplained behavior" if the airplane is computerized and it kinda knows what to expect, what about the autopilot.

 

I suppose the the graphics/geometry isn't finished and didn't reflect to the changes. Or if it's some oddbal chance that the structural attachement was damaged and made it sealed shut, but I doubt that's a feature yet.

[NineLine]

This is incorrect, the ailerons should counter this.

[unknown]

First, thanks all to help me understand the behavior. :thumbup:

 

This is correct and an aspect of an FBW system in which the FCS will use other control surfaces to compensate.

 

There was one Hornet pilot that lost a vertical stab but did not realize until after he landed.

 

I noticed immediately that something is wrong, i had to constantly push my stick to the right 1/3 to 1/2 deflection to counter the left roll.

If i understand David OC, if i push the nose down it should end in a right roll instead of the left roll? That is what i would expect, like Vilab described it. BUT i had only that left roll, no matter pushing the nose up/down which i had to counter with a constant right stick deflection. It was controllable until i lowered my gear/flaps for the landing. At this point the left roll tendency was more pronounced and i had to fight to get the FA-18 down. On the runway it tipped to the left, broke my left wing off but after some wiggle runway - lawn - runway i could stop the plane.

 

It's too bad that the track is not replaying correct, it's showing me crashing into a hill(which did not happen) before the interesting part. :cry: I guess this is because i paused the game to take the screenshots.

[aceofspades9963]

Not sure if this is for proper bug report, it may be known because it's early access and just not done yet, but some of the AAA Zu23 shot my right elevator off, it wasn't moving, but the airplace FCS reported zero problems and all of the numbers were moving normally as if nothing happened, but again, the thing was 95% missing and was not moving up or down, it was still, whatever was left of it. The left elevator had bullet hole marks but was working normally.

 

There were no cautions, no advisories, nothing.

 

Unfortunately I crashed it due to my lack of focus (late at night) just before landing, I wanted to do a FCS bit test and other stuff to make something show up.

 

 

You won't get a caution if the flight control surface itself gets damaged, there's nothing in the surface to detect that , all the FCS signals come from the servo that moves the surface, only way you would know if that takes a hit.