The Target Acquisition and Designation System, Pilot Night Vision System
(TADS/PNVS) is the combined sensor
and targeting unit fitted to the AH-64 Apache helicopter
. It comprises two independent systems, described below:
Target Acquisition and Designation System (TADS)
TADS contains stabilised electro-optical sensors, a laser rangefinder
and laser target designator. The TADS assembly can rotate +/- 120 degrees in azimuth
, +30/-60 degrees in elevation
and can move independently of the PNVS. The movements of TADS can be 'slaved' to the head movements of the helicopter
crew to point where they are looking. This allows images from TADS to be projected onto the crew helmet
-mounted optical sights
, overlaid upon their view of the cockpit
and battle space.
TADS contains a thermal imaging infrared camera and a monochrome daylight television camera. With the improvements planned with M-TADS in the block III level AH-64D, the monochrome TV-camera is planned replaced with a full color camera.
It also used to contain direct-view optics (DVO) which the copilot/gunner (CPG) could see through the Optical Relay Tube (ORT). But in recently fielded models of the AH-64D the ORT along with the DVO has been removed as it was rarely used. It has been re-placed in the co-pilot's cockpit by a third Multi Purpose Display.
Mounted above the TADS, the PNVS contains an infrared camera
slaved to the head movements of the pilot
. PNVS can rotate +/- 90 degrees in azimuth and +20/-45 degrees in elevation. PNVS has a high rate of movement (120° per second) so as to accurately match the head movements of the pilot.
A program is under way to upgrade the U.S. Apache fleet to the Modernized-TADS/PNVS (M-TADS/PNVS) standard, also known as Arrowhead. This upgrade is claimed to give a 150% performance and reliability improvement.