fixed F-5 can fly without wings and still be controllable

[VPS_Zen]

Hi,

I over G in a pull and broke my 2 wings. I was still able to fly and land the aircraft. Maybe I'm wrong, but I think that I shall not be able to control my aircraft anymore without wings.

 

Steps to reproduce:

-DCS Open Beta: version (2.7.9.17830)

-Dive fast (speed around the red triangle) and pull hard until the wings break

f5nowingsLanding.trk

[VPS_Zen]

the track is broken at the end but here are 2 pics of the landing

[Flappie]

Many thanks for the track.

Issue reproduced and reported.

EDIT: actually, the issue was reported in November.

Edited January 10, 2022 by Flappie

[Xhonas]

Hi there, as the title says. You can get it down to speeds of ~200 knots and land it just fine.

 

wingless F5.trk

[nairb121]

It's kind of a weird situation... theoretically the fuselage and wing stubs can still provide some lift, and you still have elevators for pitch and the rudder for roll. There are no fuel tanks in the wings to leak fuel when damaged, so the engines should still run. As long as the damage is symmetrical, maintaining stable flight theoretically should be possible. The main problem (and I haven't thought to check this in game) would be loss of hydraulic pressure - I'd think losing the wings should drain the hydraulic systems (since there are lines to the ailerons), I don't think they have any sort of cutoff valve in case of damage like that.

[Flappie]

You are right. I'll edit the internal report and see what devs think of it.

[=475FG= Dawger]

8 hours ago, nairb121 said:

It's kind of a weird situation... theoretically the fuselage and wing stubs can still provide some lift, and you still have elevators for pitch and the rudder for roll. There are no fuel tanks in the wings to leak fuel when damaged, so the engines should still run. As long as the damage is symmetrical, maintaining stable flight theoretically should be possible. The main problem (and I haven't thought to check this in game) would be loss of hydraulic pressure - I'd think losing the wings should drain the hydraulic systems (since there are lines to the ailerons), I don't think they have any sort of cutoff valve in case of damage like that.

Generally the ailerons and rudders are on separate hydraulic systems. The question is which system the HStab is on. 

[nairb121]

13 hours ago, =475FG= Dawger said:

Generally the ailerons and rudders are on separate hydraulic systems. The question is which system the HStab is on. 

There are 2 systems, the flight control and utility hydraulic systems. Both redundantly serve all flight control surfaces, while the utility system also controls wheel brakes, gear, speedbrakes, stability augmentation, and the gun doors.

[=475FG= Dawger]

Absent hydraulic fuses where the hydraulic lines enter the wing, all the fluid should be pumped overboard in a very short period

1 hour ago, nairb121 said:

There are 2 systems, the flight control and utility hydraulic systems. Both redundantly serve all flight control surfaces, while the utility system also controls wheel brakes, gear, speedbrakes, stability augmentation, and the gun doors.

 

[Flappie]

You mean that in the case of a ripped off wing, the plane detects lack of pressure and protects itself agasint a hydraulic fluid leak?

[nairb121]

3 minutes ago, Flappie said:

You mean that in the case of a ripped off wing, the plane detects lack of pressure and protects itself agasint a hydraulic fluid leak?

He means that, unless it has that capability to protect itself, it would be correct to rapidly lose all the hydraulic fluid.

I personally have not been able to find evidence either way, my documents don't have much detail on the hydraulic systems. I would guess though, that there wouldn't be a cutoff system like that. If damage is severe enough to cause leaks in both hydraulic systems - then odds are that much more is damaged and the airframe is lost anyway.

[=475FG= Dawger]

1 hour ago, Flappie said:

You mean that in the case of a ripped off wing, the plane detects lack of pressure and protects itself agasint a hydraulic fluid leak?

Hydraulic fuses exist as a protection feature in many hydraulic systems.

However, any such protection designed to preserve hydraulic fluid in the case of ripping the wings off would get laughed out the engineering Christmas party.

For the F-5, there is no evidence a wing has ever catastrophically failed, so we can safely say we have crossed over into never never land with this particular issue.

The fact that both wings fail precisely simultaneously, generating this issue repeatedly, is further evidence of the silliness of the whole situation. Wings just don't fail that way in flight.

At the G level required to crack the wings off, there should be many, many other associated failures. Its likely the engines would fall off their mounts and control surfaces would rip off.

Everything should be broken and the only course of action available to the pilot would be ejection before the G forces of the out of control aircraft GLOC'd him.

Just instantly shut down everything electrical and hydraulic when the wings come off and call it a day.

No need to spend time researching systems. The whole scenario is a bit far out there in arcade land.

[Flappie]

I strongly agree with you and I reported the wings fragility issue a while ago.

But in the meantime, the wingless scenario happens a lot. And being able to fly this wingless aircraft is unreal, which is why I try to get both issues fixed. Of course, if devs were to fix the wings fragility issue first, the wingless high controllability issue would get a lower priority.

[=475FG= Dawger]

12 hours ago, Flappie said:

I strongly agree with you and I reported the wings fragility issue a while ago.

But in the meantime, the wingless scenario happens a lot. And being able to fly this wingless aircraft is unreal, which is why I try to get both issues fixed. Of course, if devs were to fix the wings fragility issue first, the wingless high controllability issue would get a lower priority.

 

20 hours ago, =475FG= Dawger said:

 

Just instantly shut down everything electrical and hydraulic when the wings come off and call it a day.

No need to spend time researching systems. The whole scenario is a bit far out there in arcade land.

I suggested the most appropriate fix, in case you missed it.

Tell the devs If wingsoff then electrical = false and hydraulics = false and thrust = 0

[Flappie]

This was fixed with today's update.