[Fixed] Loss of control on long missions

[gmangnall]

I have a very odd issue which happens on long missions. Here I was trying to find the maximum range of the harrier, however after about 400 miles the aircraft starts to veer right as if some rudder is applied....this gets worse and worse and by 500 miles or so you lose complete control.  This is the video for the final few seconds of the MIZ file and as you can see the aircraft is yawing right and I am having to roll left to try and counter is...within a few seconds the aircraft completely loses control and explodes.....I tried this test at Syria and Caucasus.

 

Harrier loss of control.trk

[Aernov]

This can probably be explained, but still, this departure should be looked at, just in case. Also, in the video you have strange AoA readings on HUD, those can't be correct IMO.

NATOPS mentions cases of high-speed departures caused by simply rolling the plane (one example - 25k ft at 0.89 Mach indicated), and states SAAHS departure resistance effectiveness loss proportional to altitude and Mach number ("At 0.85 IMN at 20,000 feet there is roughly half the dynamic pressure acting on the jet as there is at the same IMN at 5,000 feet. In practical terms, that means that the aircraft has half the stability at 0.85 IMN at 20,000 feet than it has at 0.85 IMN at 5,000 feet due to decreased control power"). If you had flaps in cruise mode, this could have made the situation worse (0.87 M is the speed limit for that mode, flaps should be placed in AUTO, this will gradually retract them to less than 5 degrees). Rudder deflection is prohibited at >0.80 Mach. Thrust vectoring is prohibited above 30k ft at AoA near stall. And engine ratings above 102% RPM are limited to 15 minutes uninterrupted, but this probably won't cause such departure.

Also, I flew 600+ nm mission, only problem I encountered was running out of oil, which is correct since standard oil tank filling for Harrier is for 4 hours of flight, and I got low oil pressure warning at roughly 4 h 10 min. I wasn't flying higher than 32000 ft and faster than 0.8 Mach though, and engine rating timing was closely monitored and not exceeded.
 

Edited June 9, 2022 by Aernov

[gmangnall]

It's nothing to do with normal flight....it's a bug. The aircraft flies fine in autopilot for a few hundred miles and then starts to yaw slowly  and then quickly excalates until you need ot take manual control and roll the aircraft to maintain straight flight (which is where the recording starts) and within a few seconds it goes completely out of control..

 

[AlphaJuliet]

Wow that's weird as <profanity>, seems like some errors of calculation are accumulating over time.

I'm reporting it, we'll investigate and see where this is coming from.

Thanks for the report,

Cheers

Censoring profanities, come on we're not 5 years olds ED

[AlphaJuliet]

Should be fixed for next update, issue was infinite dumping of water was lowering the CG to like 5m below the aircraft lol. No surprise it was a tad unstable at that point.

[Kappa]

Il 10/7/2022 at 16:11, AlphaJuliet ha scritto:

Should be fixed for next update, issue was infinite dumping of water was lowering the CG to like 5m below the aircraft lol. No surprise it was a tad unstable at that point.

No sign of this fix in change log, is it fixed?

[AlphaJuliet]

Yup