correct as is Viper INS Alignment stuck at 10

[creme_fraiche]

Reproduction steps:

 

1. Engine start

2. INS to "NORM ALIGN"

3. Wait for the alignment quality to tick down

 

Expected Result:

Alignment quality should hit 6 on "NORM ALIGN"

 

Actual Result:

Alignment quality stays at 10 and goes no further

 

Track was bigger than 5MB:

https://www.dropbox.com/s/lrv02mgigvsenig/viper_ins.trk?dl=0

[Tholozor]

At work so I can't check the track, but did you confirm the starting coordinates on the DED with the ENT button on the ICP? If not the system will flag the alignment as degraded.

[AlexCaboose]

2 hours ago, Tholozor said:

At work so I can't check the track, but did you confirm the starting coordinates on the DED with the ENT button on the ICP? If not the system will flag the alignment as degraded.

Haven't checked the track either, but I believe my buddy did this as well and mentioned that confirming the coordinates doesn't seem to matter.

[Conroy]

Same here, stuck at 10.

[BIGNEWY]

This is correct as is at the moment. 

 

Status 10 is the minimum it will reach, there is not enough detailed information on how to reach status 6. 

 

thanks

[Frederf]

Status 6 should be reachable with an enhanced interrupted alignment (EIA). The requirements are:

• Perform a normal alignment with or without interruption to status 10
• Filter mode set INS (DED menus, updates invalidate EIA)
• Knob set to NAV
• Taxi of no more than 80 kts
• On new heading >70 degrees from first knob set NORM for 4+ additional minutes (status counts from 10 to 6)
• Time spent in knob NAV <10 minutes between additional alignment times
• Additional alignments repeat as necessary (best is 0 degree, 180 degree, 90 degree for three sessions)

Remember to set INS filter mode back to auto after status 6 and performing zero velocity/position update (after GPS online a plus) improves INU trimming the most.

[JabbyJabara]

12 hours ago, BIGNEWY said:

This is correct as is at the moment. 

 

Status 10 is the minimum it will reach, there is not enough detailed information on how to reach status 6. 

 

thanks

@BIGNEWYIf there was an open source document that described it would that be enough to bring it back

[creme_fraiche]

As long as A/G weapon accuracy isn’t degraded by not going down to 6. Thanks @BIGNEWY

[kotor633]

Hello,

a question: 10 or 6. What is the difference? What is the benefit for me in DCS when status 6 is reached in the alignment?

[BIGNEWY]

Hi all

 

to clarify this issue our Viper is INS + GPS, not EGI. 

 

We will be cleaning up our manual to reflect this. 

 

thank you

[Dee-Jay]

1 hour ago, BIGNEWY said:

to clarify this issue our Viper is INS + GPS, not EGI.

 

Hi!

 

You mean "IRS + GPS" ?

 

AFAIK, all US F-16 has been equipped with ring laser gyro (RLG) from the Blk30/32 standard. Unless I am wrong, all variants above the 30/32 are equipped with RLG INU.

An RLG INU is called IRS (Inertial Reference System), not INS which are mechanical gyros, not laser gyros.

Same functions are provided, but some details are basically different. An IRS has an much less internal drift is  than a INS, and some stuff are different on align init.

In manuals and panels, acronyms has never been updated.

 

As you said above, most of military IRS are now hybridized with GPS, some are embedded (EGI), the most modern and performant inertial system is now the HRG (Hemispherical Resonator Gyro) we have on Rafale (on F-35?).

 

Regards.

Edited July 25, 2021 by Dee-Jay

[Tholozor]

The whole system of the RLG INU and the INU rack is referred to as the 'INS.'