A new targeting system is aimed at giving helicopter pilots the edge during the heat of combat
Peter Gray/ORLANDO, FLORIDA
Getting dangerously close to your enemy and accidentally shooting at your own side are two hazards faced in wartime. To counter both these threats, Lockheed Martin has developed what it and Bell Helicopter Textron claim is the world's most advanced target sighting system (TSS): the Hawkeye.
Hawkeye provides accurate target detection, recognition and identification at long ranges, day and night and in nearly all weather conditions. It ring-fences friendly combatants and so protects them from "friendly" fire.
It does this by placing an electronic fence around the friendly group, be it vehicles and/or personnel. This inhibits weapons from all other friendly aircraft from penetrating the fence. This protected area is clearly marked out on the weapons officers' and pilots' displays.
Hawkeye has been ordered by the US Marine Corps for its latest acquisition, the AH-1Z SuperCobra attack helicopter. Lockheed Martin is under contract to Bell to manufacture one TSS. The equipment is also being designed to fit other helicopters and aircraft such as unmanned air vehicles and the Lockheed Martin C-130 fixed-wing transport (a downgraded version of the TSS for search and rescue). Prospective customers from Turkey, Japan, South Korea, Taiwan, Greece and Slovenia have also had demonstrations. Flight International evaluated the system at Lockheed Martin's Orlando, Florida base.
Attack helicopters are formidable weapons. Designers make use of low-observability features such as fuselages with small cross sections and exhausts which shrink the infrared signature. They fly fast and low in all weathers and make use of available cover, such as buildings or vegetation. However, the helicopter has to come within enemy weapons range for the helicopter occupants to use the sensing equipment on the nose or on top of the main rotor to view, analyse and record the scene around it.
High-performance
Hawkeye is a suite of high-performance electro-optical/infrared sensors packaged in a stabilised turret mounted on the helicopter's nose. The turret contains three apertures within an overall diameter of 520mm (20in). It consists of:
a large aperture, third generation forward looking infrared (FLIR) with four fields of view (FV) - wide, medium, narrow and very narrow. The FLIR enhances the target image to give maximum resolution to the viewer. It can "see" at night, and the only difference from daytime vision is that the images are slightly darker; a colour Sony TV camera with a Canon continuous zoom lens. The lens is capable of high magnification of the target with its fields of view matched with those of the FLIR; a laser rangefinder/target designator. This exceeds the maximum range of the onboard laser-guided weapons (Lockheed Martin AGM-114 Hellfire in the AH-1Z) and has a selectable "eye safe" mode for training and operations in an urban environment; a laser spot tracker. Used to detect and track illumination from another laser source for target cueing/identification and to facilitate the concept known as "buddy lasing" when a helicopter's weapons are guided by another's laser; an inertial measurement unit. It is installed on a gimbal for accurate line-of-sight pointing and location of targets.Hawkeye's other features include multi-target track capability. It can track three active targets simultaneously and store 10 more. As an active target is destroyed, one of the 10 is automatically upgraded to active status as long as it is in the field of view of the sensor in use at the time.
Another capability is the extended range (XR) image-processing technique developed by Lockheed Martin. This extends the FLIR target recognition and identification range performance by more than 60% over the performance of all other current equipment, says Lockheed Martin. Even without the XR feature, FLIR target identification and laser designation ranges exceed the maximum range of the Hellfire missile. This gives the aircraft a greater stand-off capability and its occupants much improved survivability. With older generation FLIRs, you had to get close(4-5km) to identify a target. The TSS's long-range capabilities give a protective zone. Hawkeye can also provide in-flight boresighting of the laser designator/ rangefinder, TV and FLIR. This means they can all be aligned simultaneously. The turret can turn through 360° continuously and rotate up 45°, down 120°.
Modular equipment
The whole system weighs 105kg (230lb). A smaller, lighter, cheaper version is available for smaller platforms - 75% of the performance at two-thirds of the cost, which will still outperform all previous systems, says Lockheed Martin.
For this evaluation, the system was fitted to Lockheed Martin's Bell 222 helicopter. The turret was mounted on the right-hand side instead of on the nose. The equipment is neat, modular and compact. As the system is developed and modified, it can be upgraded by changing a module or modules.
The system I flew was not fully developed, and the zoom facility did not have a continuous motion, while the onboard equipment was not the proposed production model. Off-the-shelf components comprise 73% of the production system, making it price competitive, says Lockheed Martin.
For the flight, I sat in the operator's seat in the passenger cabin. In front of me was a screen which portrays in real time what the sensor is looking at. A mini cyclic stick is used by the right hand to move the sensor, which otherwise points ahead. In the production aircraft the controls on the mini cyclic will be on the aircraft's mission grip.
The stick allows movement left and right, and up and down. With my right thumb I could change the field of view (FoV) between wide, normal, narrow and extra narrow. Finally, there is a trigger. One click keeps the tracking (cross hairs on screen) where you point the sensor; a second click automatically keeps the sensor on the target, even if it is moving. A second set of cross hairs with a box in the middle is for secondary tracking.
I had the FoV set to wide, which is what you would see in real life. I moved the sensor down and saw the individual blades of grass directly in front of us. As the helicopter rose above the tree level I looked out at downtown Orlando, 14km (7.5nm) away. The horizon showed indistinct skyscrapers. The view on the screen was the same. I went to medium FoV and could see a telephone pole and its wires 6-7km away. The skyline buildings were much larger and more distinctive. I aimed the sensor onto one of the buildings and selected "narrow view".
Accurate viewing
The building was now centred and I could just read its name. Selecting "very narrow view" expanded it even further, to the point where I could now place the tracker on an individual window. This is where my missile would enter.
Before TSS, you just aimed at the building at this range. Now you select the entry point. Even though I was in a fairly smooth flying helicopter, all helicopters inevitably vibrate, but the turret mounting system on its gimbal was such that the images on the screen were distinct and vibration free. This is important for accurate viewing and aiming.
We took a half-hour flight round the area, surveying various potential targets. The previous flight had reported a large fire in the area and gave us an approximate position. I swung the sensor around to look for it and found the plume of smoke in the distance using the wide-angle mode. I zoomed in and saw sparks flying. Next I picked up a truck moving right to left and selected the automatic tracker and the crosshairs on the screen stayed on the vehicle. The vehicle disappeared behind a long line of trees, lost to my view. But the system's algorithms had already calculated its speed and as it emerged from behind the trees 10s later, the crosshairs were on it.
The TV camera view of the area near the fire was hazy. The FLIR, however, looked right through the haze and presented a bright image, similar to that of a black and white movie. Using the very narrow range and zoom, I could pick out all the wires in our path. Wires are the low-flying helicopter pilot's worst enemy. What I was seeing on my screen can be projected on to the pilot and weapon's officer's visor in the production model. Swinging the sensor through 360° I could see the front right-hand side of the aircraft and the tail.
This equipment is a major advance on all the other systems I have experienced in combat helicopter test flights. It should enable its crew to keep the aircraft and its occupants beyond enemy fire range and also protect one's own people who may be in the line.
Source: Flight International
