[MISSING TRACK FILE] Loss Of Engine And Avionics While Maneuvering

[Emmy]

This has happened twice since the latest update came out and it's got me stumped...

 

Working on a MP mission for our squadron flight night this week and just for fun, I decided to "Bait and Bail" on an SA-8 that I have defending Qesham Airbase. Lazy turn in at around 16,000' feet, get locked up, eyeball the launch, punch out some chaff, chop the throttle and roll/pull to beam the missile in about a 70 to 80-degree nose down attitude. The missiles don't have a chance of connecting.

 

Both times I've done this, I've had an engine shut down (first time right, second time left), my avionics all went off line (blue screens on both MFCDs), all four channels of SAS disconnected, my NAV alignment went away completely and I lost all the hydraulics on the dead engine side.

 

The first time I thought "Bird Strike?" or maybe unseen AAA? But in the F2 view, there is no external damage of any kind. I just exited the mission the first time but the second I got curious and decided to work through the problems to try and wake everything back up. Was able to re-start the dead engine and also performed an In Flight INS re-alignment Other than my NAV points being off by a bit due to the IFINS, everything eventually returned to normal.

 

I don't have a Track File to share simply because I'd already been flying for well over two hours so the resulting file would be YUGE! but I just wanted to post this to see if there's something "new" in the Hog that precludes excessive nose down attitudes and whether or not anyone else has encountered this?

 

For the record, AFAIK, I never put negative Gs on the jet.

 

Like I said, I've never encountered this particular behavior before so I wanted to open this up to the collective Hog Mind.

[Canada_Moose]

When you “chop” the throttle are you inadvertently shutting the engine down?

 

Calibration / mapping issue?

 

Open beta (if you are using it) sometimes does odd things to control assignments.

[Yurgon]

It was in a similar situation (trying to get to low level quickly, without overspeeding the airframe) when I discovered that the Hog absolutely doesn't like high airspeeds in combination with throttles set to idle. Not sure what the recommended throttle setting is in this situation; I try to give it at least about 1/3 and make sure not to overspeed by pitching up (or using the airbrake if the dive is really urgent).

 

As I understand it, the engines are prone to flame-out in this type of situation and to the best of my knowledge the behavior is correct.

 

However, I'm not sure why your instruments shut down; with one engine still operational, nav alignment should have remained okay and the remaining generator should have been able to provide sufficent AC power. When I had this happen, I had a dual engine shutdown and the resulting avionics failure was to be expected, running only from the battery. If you manage to repeat it, a track would be most interesting to figure out why some of the avionics failed with one engine still running.

[Emmy]

Interesting thought Yurgon. I’ll have to keep that in the back of my mind.

[Emmy]

Had to spoof an SA8 in the same fashion today while working on a mission. Left a few hundred extra RPMs on the engines and had no issue. Just had to pull level a little more aggressively but otherwise, all good.

[Sierra99]

Emmy you're not in a negative gee dive are you? I've had the same thing happen a few times screwing around diving straight at the ground to go as fast as possible only to have both engines flame out...just a thought.

[Emmy]

Emmy you're not in a negative gee dive are you? I've had the same thing happen a few times screwing around diving straight at the ground to go as fast as possible only to have both engines flame out...just a thought.

 

Nope. Definitely did not “push” at all. Rolled over and pulled. It is possible however, that in a very steep dive, you might put negative Gs on one engine if you roll aggressively while pointing pretty much straight down.

 

Hmmm......

[Gruw]

Yurgon said:

It was in a similar situation (trying to get to low level quickly, without overspeeding the airframe) when I discovered that the Hog absolutely doesn't like high airspeeds in combination with throttles set to idle. Not sure what the recommended throttle setting is in this situation; I try to give it at least about 1/3 and make sure not to overspeed by pitching up (or using the airbrake if the dive is really urgent).

 

As I understand it, the engines are prone to flame-out in this type of situation and to the best of my knowledge the behavior is correct.

 

However, I'm not sure why your instruments shut down; with one engine still operational, nav alignment should have remained okay and the remaining generator should have been able to provide sufficent AC power. When I had this happen, I had a dual engine shutdown and the resulting avionics failure was to be expected, running only from the battery. If you manage to repeat it, a track would be most interesting to figure out why some of the avionics failed with one engine still running.

 

 

Same, it's happened to me 15 days ago during a dive45, throttle in idle.

Edited December 5, 2020 by Gruw

[Gruw]

This issue seems to be solved to me.

[Emmy]

This issue seems to be solved to me.

 

 

Yeah, I haven't experienced this lately either.

[Gruw]

Here we are!

 

This issue seems to be alive again, 2 times tonight during HADB45 with the IDLE throttle.

Someone noticed the same behaviour ?

[Adamastor]

Same here.

This time I was sure I wasn't in negative G in a 35/45° dive, roll, and only 1 engine shut down.

 

I agree with @Yurgon hi speed and throttle combination has some effect in this situation and also like @Emmysays, much more frequent now since last update.