Loosing a primary INS

Olympic Supersonic operations.
Post Reply
User avatar
OAL269 Kyprianos Biris
Global Moderator
Global Moderator
Posts: 331
Joined: Sat Aug 14, 2010 4:25 pm
Name: Kyprianos Biris
Callsign: OAL269

Loosing a primary INS

Post by OAL269 Kyprianos Biris »

Loosing #1 or #2 INS will fail the subsequent attitude indicator which leads to autopilot 1 (or 2 respectively) disconnect.
If you don't react fast the aircraft at FL500+ and Mach 2 can get easily out of control by hand flying.

It happened to me at dark (minimal sense of visual horizon) crossing from Lebanon to Syria over desert !

If it happens this is a quick remedy before you loose control:

If you fly on Autopilot 1 and and loose INS1
Flip all captain side switches to the other side, engage Autopilot 2 (using INS2) and Authrottle 2 and from there onwards fly as copilot (i.e. starboard side HDG controller for heading) and monitor copilot's HSI, not the captain's. Captain's Attitude Indicator will be fed by No.2 INS.

If you fly on Autopilot 2 and loose INS 2 do the opposite from the above, flip copilot's side switches and continue flight with Captain's instruments on Autopilot 1 and Autothrottle 1.

The subject flight:
PIREP:
http://www.oav.gr/pages/fskeeper/PIREPD ... ?ID=208745
Map:
http://www.oav.gr/oavacars/map/index.asp?id=208745
VATAWARE:
http://www.vataware.com/flight/5613e6435352333ac500000a

CIVA INSs have their own failure factors that can not be disabled like the failures of FSLabs for the aircraft. Once in a while they may fail but its rare !
Image
P3Dv5.4 - CPU i9 10900 / GPU RTX 3070
OAL109 Mike Ionas
Administrator
Administrator
Posts: 1276
Joined: Mon May 31, 2010 6:09 pm
Name: Mike Ionas
Callsign: OAL109

Re: Loosing a primary INS

Post by OAL109 Mike Ionas »

It happened to me today while flying from Petropavlosk to Anchorage. I lost INS1 and immediately AP1 was disconnected while cruising at Mach 2. I was lucky because the flight was stable at the moment, giving me time to perform all necessary actions while not losing control. Last time it happened, having to fly with the right hand and trying to open the various panels with the mouse and the left hand (I am right handed) did not end up very well..

And this was only the beginning of a bad day as arriving in Anchorage in a not so ideal weather condition, while getting 10-15 frames as I haven't disabled some stupid traffic options from the scenery manager, ended up in a go around followed by a missed approach and a heavy landing. Check the flight map here.
Image
Post Reply