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Tester
February 20, 1997

AH-1W Cobra Night Targeting System improved

By Ted Gross

PROJECT ENGINEER

An improved variant of the Night Targeting System (NTS), is under going developmental test at the Naval Rotary Wing Aircraft Test Squadron at the Naval Air Warfare Center Aircraft Division (NAWCAD) on the US Marine Corps AH-1W SuperCobra attack helicopter.

Designated NTS "A", the new system detects, acquires, tracks, ranges and laser designates tactical targets under daytime, nighttime or adverse conditions. Other capabilities include the ability to fire and guide BGM-71 tube launched, optically-tracked, wire-guided (TOW) missiles; fire and laser self-designate for AGM-114 Hellfire anti-armor missiles; laser designate for NATO compatible laser-guided ordnance; and control the M197 20mm turret.

The NTS, a modification to the M-65 Telescopic Sight Unit designed by Hughes Aircraft Corporation in the early 1970's, is the sensor suite currently being installed on fleet AH-1W Cobras.

The M-65 employs a two field of view, direct view optics (DVO) system that can be slewed vertically and horizontally for target acquisition and tracking. The two fields of view provide 2X and 13X magnification to the operator in the front seat of the aircraft.

The NTS improved upon the basic M-65 by incorporating an onboard laser designator/rangefinder, a forward looking infrared (FLIR) sensor adjacent to the gimbal mounted optics, and a charge coupled device (CCD) camera mounted within the M-65, about midway in the optical relay tube (ORT) that extends into the forward cockpit. The CCD camera and FLIR images are displayed to the operator on either a 1 square-inch cathode ray tube within the ORT, or on a 5 square-inch multifunction display (MFD), both of which are monochromatic.

The original M-65/NTS optics reduce about 70 percent of the light available at the objective lens through the optical train. Therefore, the low light level (i.e., dusk/dawn) performance of the DVO and CCD is degraded. Furthermore, the relatively low magnification of the DVO requires the attack helicopter pilot to close with the target to efficiently employ his weapons, reducing aircraft survivability by decreasing standoff from enemy weapons.

The NTS "A" program intends to improve upon the basic NTS by completely removing the DVO and replacing them with high resolution, gimbal mounted CCD cameras. The NTS "A incorporates two CCD camera heads mounted on the slewable gimbal in the space vacated by the optics.

The ORT has been removed from the forward cockpit, leaving only the 5 square inch monochrome MFD for sensor display to the operator. The two camera head arrangement provides four fields of view and an order of magnitude increase in magnification. Since more light is provided to the CCD, a substantial increase in low light level performance is anticipated. The responsiveness of the CCD to near infrared wavelengths is also expected to improve sensor performance through obscurants, such as haze, dust, etc., and possibly provide the capability to view the downrange location of the onboard laser designator spot.

Ground testing on the system installed in the AH-1W has consisted of an aircrew systems cockpit survey, an electromagnetic environmental effects (E3) evaluation, laser performance, and forward looking infrared (FLIR) and television camera (TVC) performance.

Flight testing has been conducted in the Pax River area for evaluating FLIR and TVC airborne performance, and at Ft. A.P. Hill, Va., for the NTS "A" TOW and 20mm live fire performance evaluation. To date, nine BGM-71C-1A improved TOW and three BGM-71E-5B TOW2A missiles have been fired during testing. TOW and Hellfire live fire flights and further sensor performance flights are still slated. According to project officer, Maj. Paul Schreck, and lead engineer, Wes Brubacher, the system**,** is performing as advertised so far and promises to be a key weapons system upgrade for the Cobra.

Some immediate improvements include: the removal of the ORT, which has been an obstruction to the operator in the front cockpit, and could inflict serious injury in the event of a hard landing or crash; doubling of the TVC magnification with the two CCD cameras from the current NTS TVC in narrow field of view ; and incorporation of a video thermal tracker (VTT) that serves as an alternate TOW missile guidance tracking loop in the event that the optical guidance loop becomes compromised by smoke, dust or infrared countermeasures (IRCM). The new system design saves roughly 50 pounds in weight over the current NTS and improves the baseline software.

The test aircraft recently completed a phase inspection and has just returned to flight status. Testing will resume with a TVC resolution flight, a NTS/NTS "A" side-by-side comparison flight with a second NTS equipped Cobra, followed by Hellfire and 20mm live fire flights.

The side-by-side comparison flight and Hellfire live fire flight are scheduled to be conducted at the Aberdeen Proving Ground. Successful VTT testing will complete the developmental test phase here. Test team members are: Maj. Paul Schreck, project officer; Col Paul Martin, Maj. Troy Caudill and Maj. Ken Loy, project pilots; Gunnery Sgt. Albert Stiney, Range and Ordnance Detachment OIC; Wes Brubacher and Ted Gross, project engineers; and Dale Vallandingham and Steve Soaper, project technicians.


Last updated: 2.20.97