F-14 INS: F/F LINK 4C and Unorthodox Fixes (CVDLHBWP, Pod, NS430)

So far we have seen the details of two INS fix methods: the TACAN Fix and the Visual Update. This article introduces the Fighter-to-Fighter Nav Update (which I dubbed “buddy-INS“, from buddy-lasing) and some.. less SOP-conforming methods.


F/F Navigation Update

This method allows an F-14 to update its position by receiving a set of coordinates from another F-14. This simplifies the nav update of a group of F-14 by having only one aircraft performing an accurate INS fix and then share it to others.
The procedure is very simple. From the manual:

Net aircraft that use fighter-to-fighter data link can update their navigation system in the FF/DL mode. To update LAT/LONG hook the net aircraft symbol of an aircraft that is in close proximity and select F/F NAV UPDATE on the CAP. This will enter the hooked aircraft’s coordinates into the INS as own-aircraft coordinates. To update the nav system on an aircraft that is not close, first obtain a radar STT on that aircraft, hook the STT-ed aircraft on the TID and then press F/F NAV UPDATE on the CAP.

Once set, press the usual FIX ENABLE to download the INS fix. This method uses the Fighter-to-Fighter Datalink mode (LINK4C – Brevity: DOLLY) so make sure that this DL mode is selected and the frequency matches.

From the test I conducted with the 108th vSq, this method is not only easy and quick, it’s also precise. With no radar lock, the position Δ is not taken into account, therefore the INS will be exactly the same as the donor. If the aircraft are flying in close formation, this is not a problem. For nav updates at longer distances, I recommend using the radar as described by the manual.

Remember that if the aircraft position of the donor is heavily degraded, this procedure can cause more harm than good.

Necessity is the mother of invention

As long as the F-14D is not available (AFAIK mainly due to the fact that some information is still classified) we have to find as many methods as possible to solve the issues we run into and shortcomings of our beloved aircraft. This, of course, happens in real life as well but with limitations that in DCS are a non-factor.

Unorthodox method I: LANTIRN

The LANTIRN pod has its own independent GPS and its reading can be used to obtain a constant and precise indication of the position of the aircraft. The RIO simply has to input such data in the CAP, Own Aircraft, and confirm the new set of coordinates.
Since the F-14 is moving, the latlong values must be set according to the future position of the F-14 and ENTER must be pressed as soon as the values match.

rio17-INS-fix-others-LANTIRN
LatLong coordinates from the LANTIRN pod

If well timed and coordinated with the pilot, this method allows to correct the F-14 position in no longer than a few seconds.

Unorthodox method II: LINK4A DL and CV

The Carrier appears as a Datalinked Homebase Waypoint on the TID when the Datalink is tuned to the CV’s frequency (I abbreviated it as CV DL HB WP, as you have correctly guessed from the title 😛 ). Since the CV is a TCN station as well, my first idea was using the TCN fix procedure along with the CV DL HB WP as the TCN station WP but unfortunately it doesn’t work.
The waypoint can still be used in two ways, although none of them is as precise as my initial idea would have been. The procedure is simple: another WP can be created over the position of the CV and quickly used to perform either Visual or TCN update. Considering the intrinsic imprecision of the analog INS of the F-14 and the fact that the CV doesn’t move fast at all (the movement can be compensated by placing the WP at a distance proportional to the speed of the CV, if necessary), this method can be used to achieve decent results, especially in the case of heavily degraded INS, and if no standard methods are applicable.

rio17-INS-fix-others-CV-datalink
CV Datalinked Waypoint

Unorthodox method III: NS 430

I bought the NS 430 module during a sales back when it was available only for the Mi-8. It is now available for almost any module, in a couple of which in its original 3D version, as a 2D overlay for the others (warning, the 2D overlay had or still has issues with VR, as far as I know).
You have probably understood already where I’m going, after the discussion about the LANTIRN: the plan is using the GPS data from the NS430 to update the F-14 position.

rio17-INS-fix-others-NS430
NS 430 and F-14B

On top of that, the NS430 is a useful navigation tool, it provides a moving map and other information and functions. I don’t feel the need of it between TCN and INS, but it can be a handy backup tool indeed.

Fun fact: some F-14 crews have used portable Garmin GPS to help them navigate.

Advertisements

One comment

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.