INS fix at sea

[DJReedoo]

Does anyone know how F-14 crews would realign their INS during long missions in the middle of the ocean ?

[speed-of-heat]

see the section on INS drift chucksguides.com/aircraft/dcs/f-14b/#[538,"XYZ",0,540,null] which has a couple of approaches.

but my guess would be via tacan , radar maybe if you can find something in range 

Edited January 4, 2024 by speed-of-heat

[DJReedoo]

The problem with TACAN and radar fix is that you wouldn't have enough range if you operate in the middle of the Pacific Ocean for example. But maybe you can use the carrier as the fix point for a radar or TACAN fix.

[RustBelt]

TACAN can reach pretty far at high altitudes. And unless it’s a hard ferry flight, you’re never going blue water for too long, or you’re flying with something with a more robust INS that can Link4 with you like a tanker every couple hundred miles. 
 

And there’s also the good old handheld Garmin GPS to poop out LAT/LON for you.

 

The important thing is setting up and being gentile with the INS and pulling a fix as late as you can before a long stretch. 

Edited January 5, 2024 by RustBelt

[QuiGon]

9 hours ago, DJReedoo said:

The problem with TACAN and radar fix is that you wouldn't have enough range if you operate in the middle of the Pacific Ocean for example. But maybe you can use the carrier as the fix point for a radar or TACAN fix.

How is that supposed to work as the carrier is a moving object with no fixed coordinates?
 

8 hours ago, RustBelt said:

And there’s also the good old handheld Garmin GPS to poop out LAT/LON for you.

That wasn't a thing for most of the Tomcat's service time.

Edited January 5, 2024 by QuiGon

[draconus]

21 minutes ago, QuiGon said:

How is that supposed to work as the carrier is a moving object with no fixed coordinates?

https://heatblur.se/F-14Manual/general.html#data-link-update

There's also https://heatblur.se/F-14Manual/general.html#fighter-to-fighter-navigation-update

[AKarhu]

I'd take a practical guess that for most missions spent entirely over blue water, the accuracy of the inertial was mostly really just good enough. If you are supposed to keep station over the deep blue, being thereabouts within some miles would do just fine for practical purposes. And if navigating into somewhere, you'd just need to get close enough to be in range of navigation aids near the said somewhere and more or less where you'd expect to be, and then get a more accurate fix from thereon.

[speed-of-heat]

1 hour ago, draconus said:

https://heatblur.se/F-14Manual/general.html#data-link-update

There's also https://heatblur.se/F-14Manual/general.html#fighter-to-fighter-navigation-update

I had forgotten DL update

[Sideburns]

Bear in mind the RIO was typically also doing manual navigation techniques as a backup, the AWG9 was not 100% reliable!

[RustBelt]

16 hours ago, QuiGon said:

How is that supposed to work as the carrier is a moving object with no fixed coordinates?
 

That wasn't a thing for most of the Tomcat's service time.

 

Most of the tomcat’s service was puttering around a boat for an hour or two.