DarkStar (LO HAE UAV) Program


DarkStar, also identified as the Low Observable High Altitude Endurance (LO HAE) or TierIII­ UAV, is intended to provide critical imagery intelligence from highly defended areas. DarkStar trades air vehicle performance and payload capacity for survivability features against air defenses, such as its use of low observable technology to minimize the air vehicle's radar return. Its payload may be either SAR or EO. The air vehicle may be self-deployable over intermediate ranges. The HAE Common Ground Segment (CGS) will provide launch and recovery and mission control elements (LRE and MCE) that are common and interoperable with Global Hawk. DarkStar's prime contractor is the Lockheed Martin/Boeing team.



Air Vehicles (TBD)
1 Common Ground Segment


Sensors: EO or SAR
Deployment: Multiple C-141/C-17/C-5 sorties
Radius: >926 km (>500 nm)
Endurance: >8 hrs (at 926 km/500 nm)
Max Altitude: >13.7 km (>45,000 ft)
Cruise Speed: >463 km/hr (>250 kts)

Funding ($M):

RDT&E (Defense-wide)





Program Status

Following its 1June 1995 rollout and a series of ground tests, DarkStar flew successfully on 29March 1996, a first fully autonomous flight using differential GPS. On its 22 April second flight, however, its "wheel-barrowing" characteristic on takeoff roll increased to uncontrollable "porpoising" oscillations after breaking ground, and the aircraft stalled nose-high and crashed. The accident board identified the cause as inaccurate prediction of air vehicle/ground interaction, which had led to an engineering change to the flight control system before the second flight. Corrective action will include "hiking" the nose gear at rotation during takeoff, simplifying flight control laws during the takeoff phase, and adding the capability to abort takeoffs. Software testing and reconfiguration of AV #2 are currently projected to allow the Phase II flight test program to resume in 3Q/FY1997. Meanwhile, radar cross-section (RCS) test results validated DarkStar's low-observable design.

The Congress has provided an additional $28.5 million for FY 1997, of which $22 million supports design changes and their integration into AV #2, $3.5 million is for further EO sensor development, and $3 million is for long-lead procurement of AV #5. One effect of the program delay has been to realign DarkStar's flight and system test schedules to better support user demos and provide comparable DarkStar-Global Hawk maturity for DARO's force mix study, both of which will be key to a HAE UAV production decision in FY2000.

 Deep-Look Reconnaissance of Highly Defended Areas

 DarkStar's Second Flight, 22 April 1996

 DarkStar's Radar Cross-Section Test

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image size: 31Kb

 Aircraft's porpoising motion increases to a
nose-high stall as it leaves the ground-effect régime

 AV #2 in position on "the pole"
for RCS testing, May 1996


 The high-priority DarkStar program will demonstrate a warfighting capability that the U.S. has not had since the early days of the SR-71 and U-2. While the program experienced an unfortunate setback with the crash last April, I am confident that it will demonstrate outstanding performance as it begins flying again in FY 1997. The DarkStar's ability to penetrate heavily defended areas and collect significant amounts of high-resolution imagery will provide the Joint Forces Commander with unprecedented access to battlefield information.

Larry Lynn
Director, Defense Advanced Research Projects Agency
October 1996

The HAE UAV System

DarkStar and Global Hawk, with their Common Ground Segment (see page26), form the HAE UAV system. The two air vehicles are complementary: DarkStar will provide a capability to penetrate and survive in areas of denied airspace, while Global Hawk's even greater range, endurance and multi-sensor payload will provide broad battlefield awareness to senior command echelons. Their CGS will assure both their interoperability and relay of their sensor products to the C4I infrastructure. Thus, the HAE UAV system will provide the joint warfighter with an unprecedented degree of broad reconnaissance-surveillance coverage and flexibility.