How do jet fighters navigate?

[barryward12345]

Considering the wide areas around the world in which they operate, I guess they don't use the "normal" domestic aircraft navigation facilities that are available - or do they??

Barry

 

[Bone]

The GPS system, for worldwide ops, which the US government owns. The US government has a 1 meter navigation performance locked for it's own use, and for it's allies use. About a decade or so ago they made a "detuned" GPS function available to commercial and private operators, but it's a 16 meter navigation performance. Before GPS, it was inertial navigation, before that, celestial nav. I'm not sure if the military used the Omega nav system or not. They still use the TACAN system, which is a militarized VOR/DME network, but it has limitations. The TACAN system goes back to at least the early 1960's.
The Russians have a system that is comparable to GPS.

 

[PRB]

FA-18s still have and use an INS, it's just constantly updated by GPS. They can still use the INS the "old way" without the GPS input if the GPS reciever goes on the fritz. Air forces of many other countries use the civilian VOR system also, rather than the US practice of using TACAN instead. Always thought it was odd that US military planes don't make use of the civilian VOR/DME system that's out there.

 

[Bone]

Always thought it was odd that US military planes don't make use of the civilian VOR/DME system that's out there.

Well, they do actually. Military flights that are on an airway can use VOR stations that are used to define that airway. Not every station is a VORTAC, so they have to be able to tune a VOR or VOR/DME station. But, that's not tactical navigation. They're just flying in the system like the rest of us. An interesting thing about navigating with a GPS, is that in most cases you are just using it to navigate to a ground station or intersection along the airway, without tuning in the ground station frequency. You input the identifier for the station into the box, and the GPS directs you to the physical location. I've been cleared direct to a nav station that was temporarily out of service. It was legal because the controller could see that we were equipped with GPS.

 

[PRB]

So... (this has always been so confusing to me) If a TACAN station is "co-located" with a VOR station, we have "VORTAC". But not all VOR stations have TACAN, and I'm assuming some TACAN stations don't have VORs, and those are just TACANs? But in the FA-18 at least, there is no means to tune a plain VOR station. You can only select TACAN "channels". So if they are flying an airway defined by VOR stations that are not VORTACs, they can't tune in the VOR station. Maybe with the ADF feature of the comm system, which lets you get a bearing on any radio you can dial in a frequency for, but that wouldn't get you distance...

 

[Bone]

You can use the GPS to navigate to a ground station without actually being able to tune it in with a VOR reciever. Take another look at the response above, I ammended it while you were asking this question. If your GPS is not working, you have to be able to tune in a VOR or identify it through other means...ie intertial nav.

 

[harrybasset]

I thought I had read somewhere that all GPS is now to the precise military standard. This was in a Techno/Spy thriller genre novel, perhaps that was just Authors licence?

Where I live it seems that F-15s from Lakenheath use a prominent ruin for visual updates on their track.