Loss Of Engine And Avionics While Maneuvering - ED Forums
 


Notices

Reply
 
Thread Tools Display Modes
Old 03-26-2019, 07:47 AM   #1
Emmy
Senior Member
 
Emmy's Avatar
 
Join Date: Oct 2016
Location: Arizona
Posts: 2,125
Default Loss Of Engine And Avionics While Maneuvering

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.
__________________

http://www.476vfightergroup.com/content.php
High Quality Aviation Photography For Personal Enjoyment And Editorial Use.
www.crosswindimages.com
Emmy is offline   Reply With Quote
Old 04-30-2019, 12:38 PM   #2
Canada_Moose
Member
 
Join Date: Jan 2018
Posts: 146
Default

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.
Canada_Moose is offline   Reply With Quote
Old 04-30-2019, 02:24 PM   #3
Yurgon
Campaign Tester
 
Yurgon's Avatar
 
Join Date: May 2010
Location: Germany
Posts: 7,801
Default

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.
__________________
Yurgon is offline   Reply With Quote
Old 04-30-2019, 06:24 PM   #4
Emmy
Senior Member
 
Emmy's Avatar
 
Join Date: Oct 2016
Location: Arizona
Posts: 2,125
Default

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

http://www.476vfightergroup.com/content.php
High Quality Aviation Photography For Personal Enjoyment And Editorial Use.
www.crosswindimages.com
Emmy is offline   Reply With Quote
Old 05-01-2019, 02:28 AM   #5
Emmy
Senior Member
 
Emmy's Avatar
 
Join Date: Oct 2016
Location: Arizona
Posts: 2,125
Default

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.
__________________

http://www.476vfightergroup.com/content.php
High Quality Aviation Photography For Personal Enjoyment And Editorial Use.
www.crosswindimages.com
Emmy is offline   Reply With Quote
Old 05-01-2019, 03:02 AM   #6
Sierra99
Beta Tester
 
Sierra99's Avatar
 
Join Date: Apr 2012
Location: Orlando Florida
Posts: 2,292
Default

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.
__________________

Primary Computer
ASUS Z390-P, i7-9700K CPU @ 5.0Ghz, 32GB Patriot Viper Steel DDR4 @ 3200Mhz, ZOTAC GeForce 1070 Ti AMP Extreme, Samsung 970 EVO M.2 NVMe drives (1Tb & 500 Gb), Windows 10 Professional, Thrustmaster Warthog HOTAS, Thrustmaster Warthog Stick, Thrustmaster Cougar Throttle, Cougar MFDs x3, Saitek Combat Rudder Pedals and TrackIR 5.

-={TAC}=-DCS Server
Gigabyte GA-Z68XP-UD3, i7-3770K CPU @ 3.90GHz, 32GB G.SKILL Ripjaws DDR3 @ 1600Mhz, ZOTAC GeForce® GTX 970.
Sierra99 is offline   Reply With Quote
Old 05-01-2019, 03:41 AM   #7
Emmy
Senior Member
 
Emmy's Avatar
 
Join Date: Oct 2016
Location: Arizona
Posts: 2,125
Default

Quote:
Originally Posted by Sierra99 View Post
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......
__________________

http://www.476vfightergroup.com/content.php
High Quality Aviation Photography For Personal Enjoyment And Editorial Use.
www.crosswindimages.com
Emmy is offline   Reply With Quote
Old 05-02-2019, 05:58 PM   #8
AMVI_Groove
Member
 
AMVI_Groove's Avatar
 
Join Date: Nov 2017
Location: Italy
Posts: 116
Default

Quote:
Originally Posted by Yurgon View Post
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, thrust in idle.
AMVI_Groove is offline   Reply With Quote
Old 10-17-2019, 06:49 PM   #9
AMVI_Groove
Member
 
AMVI_Groove's Avatar
 
Join Date: Nov 2017
Location: Italy
Posts: 116
Default

This issue seems to be solved to me.
AMVI_Groove is offline   Reply With Quote
Old 10-17-2019, 10:21 PM   #10
Emmy
Senior Member
 
Emmy's Avatar
 
Join Date: Oct 2016
Location: Arizona
Posts: 2,125
Default

Quote:
Originally Posted by AMVI_Groove View Post
This issue seems to be solved to me.

Yeah, I haven't experienced this lately either.
__________________

http://www.476vfightergroup.com/content.php
High Quality Aviation Photography For Personal Enjoyment And Editorial Use.
www.crosswindimages.com
Emmy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT. The time now is 09:35 AM. vBulletin Skin by ForumMonkeys. Powered by vBulletin®.
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.