The Wide Area Display (WAD) in Gripen E is a panoramic high-resolution screen that allows intelligent presentation of information. The single screen replaces three large displays and presents the pilot with a large panoramic view of the area surrounding the aircraft. The information display includes mission routes, approaching threats and a lot more coming in from sensors, radars and data feeds from other aircraft. Credit: Saab.

Electronic warfare, or EW, plays a vital role in today’s air force combat tactics.

Essentially, a fighter jet must be able to find and destroy enemy targets in an electromagnetic environment that is jamming its electronic radars.

This may include the use of X-rays, visible light, infrared, microwaves and radio waves.

For instance, the US Air Force is now arming F-15C fighter jets with a new kind of sensor targeting pod that can find and ultimately help destroy targets otherwise undetectable to standard fighter-jet radar detection, National Interest reported.

It is called the Legion Pod, an Infrared Search and Track (IRST) targeting technology recently tested by the Air Force in Alaska during the Northern Edge 2021 wargame. 

Now ready for operational service, it identifies targets beyond the typical scope of electronically scanned radar by virtue of using an “out-of-band” sensor, or a method of detection outside of the frequency bands employed by standard radar.

Meanwhile, Swedish defense and aerospace company Saab, which manufactures Gripen fighter jets, has come up with a novel way to prevail in high-tech air-to-air engagements in GPS-denied areas, The EurAsian Times reported.

Jonas Jakobsson, an experimental test pilot with Saab, explained the importance of platform position in a challenging EW environment.

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Jakobsson emphasized the need for pinpoint accuracy and how even mere meters make all the difference in combat.

In today’s air operations, the margin for error remains incredibly low and even a minor one may have far-reaching consequences resulting in collateral damage.

Recent wargames in Scandinavia have also highlighted how the jamming of GPS can be a gamechanger.

So, what is Saab proposing?

According to the EurAsian Times, the aerospace giant intends to pool inputs from its existing TERNAV terrain navigation system using a real-time odometry imager from a camera installation coupled with a 3D mapping surface model supplied by Maxar Technologies (a leading space technology and intelligence company).

If that sounds complicated, it definitely is.

The company claims that this will provide a far more significant positional accuracy than using traditional inertial measurement systems in GPS-denied areas.

The key highlight is the aircraft can perform its own navigation without relying on outside systems like fixed towers or satellites etc.

Following a demonstration in 2018 with a pod mounted camera, in 2020 a further demonstration was carried out integrating the algorithms on a Gripen E fitted with an electro-optic sensor installed in the fuselage. Credit: Saab.

Saab’s TERNAV backbone is an algorithm fed by radar and laser altimeter. It is the company’s own version of the Inertial Navigation System (INS).

Currently, positioning systems are based on INS, IN which drift is corrected by Global Navigation Satellite System (GNSS) data when these are available; manual support where the pilot inputs a fix, as well as conventional Navaids such as VOR, DME and TACAN, are seldom used.

In short, without the GNSS help the position error will increase with time due to the inherent drift of the INS. Saab is therefore replacing the loss of a GNSS fix with data provided by a fusion of terrain navigation and image-based navigation.

All of that crucial data is fed into the Gipen pilot’s Wide Area Display (WAD), a panoramic high-resolution screen packed with information.

The single screen replaces three large displays of the older version and presents the pilot with a large panoramic view of the area surrounding the aircraft.

The information on the WAD includes mission routes, approaching threats and a lot more coming in from sensors, radars and data feeds from other aircraft.

It also suggests handling of the aircraft such as deployment of Gripen’s counter measure systems, weapon selection etc.

The TERNAV employs a radar altimeter that compares the measured height profile with the terrain database. This technology is well proved and has already been flight tested in the JAS39 Gripen. Credit: Saab.

As Saab test pilot Robin Nordlander told The Drive, the Gripen E was designed keeping the pilot in mind.

The advanced human-machine collaboration is meant to ensure that the platform and pilot work together seamlessly.

“When it comes to sensor fusion, this is all about maintaining the absolute maximum situational awareness. You can have the greatest kinetic performance in the world, but without situational awareness, you’re a sitting duck,” he said.

“In Gripen E we talk about transparent fusion. I need to know what sensors/platforms are providing which data and what the quality of that data is, to be able to make the best possible decision!

“It is also crucial to know what the opponent knows about me, in the decision making.”

Saab and Maxar have carried out flight testing in 2018 with a pod mounted camera.

In 2020 a further demonstration was carried out integrating the algorithms on a Gripen E/F demo aircraft fitted with an electro-optic sensor installed in the fuselage, the system processing the scenery in real time.

Full operational capability is expected within three to five years, the company said.

Is there a drawback to TARNAV?

Indeed, there is.

Experts say that TERNAV is an active system with radar altimeter emissions that risk giving away the aircraft presence to the opponent.

Nevertheless, existing Gripen users have reportedly expressed interest in the novel technology, which may not be merely limited to the jet fighter.

Such navigational innovations may even see potential incorporation in the GlobalEye and unmanned air vehicles, plus air-launched weapons.

The Pakistan Air Force uses the Saab-2000 Airborne Early-Warning & Control aircraft,  which gives rise to the possibility that it might adopt Saab TERNAV for its aerial fleet.

India might not be a potential customer as it uses the NAVIC system.

Sources: The National Interest, The Eurasian Times, European Defense Review, Saab Group, The Drive