Sandblaster
DARPA PROGRAM TO GIVE HELOS THE ABILITY TO LAND IN ZERO-ZERO BROWNOUT CONDITIONS.
The Defense Advanced Research Projects Agency (DARPA) Strategic Technology Office is soliciting proposals under a broad agency announcement for the performance of system research, development, design and testing to support the DARPA Sandblaster program. Sandblaster is a high-priority effort to develop and demonstrate effective affordable solutions to the problem of helicopter landing in brownout as well as other degraded visual environments (DVE). Solutions are urgently needed for the brownout phenomenon, which causes deadly accidents during helicopter landing and take-off operations in arid desert terrain. Intense, blinding dust clouds stirred up by the aircraft’s main-rotor down-wash during near-ground flight can cause helicopter pilots to suddenly lose all visual cues. This creates significant flight safety risks from aircraft and ground obstacle collisions, rollover due to sloped and uneven terrain, etc.
Sandblaster is focused on the rapid development and demonstration of sensor/visualization-display systems that will provide an affordable, effective landing capability in brownout/DVE conditions where the visibility is zero with zero landing-zone infrastructure and no ability to observe terrain comprising the landing area. Sandblaster must be affordable and self-contained, and include necessary sensors, instruments and displays to provide robust effective landing guidance to the pilot. Sandblaster must be compatible with upgrading existing military rotorcraft like the UH-60 Black Hawk. System A-Kit must be configurable to integrate with UH-60 A/L/M Black Hawks
DESIRED CHARACTERISTICS
The preferred Sandblaster system will, at a minimum, provide zero-visibility brownout landing capability with warning of lateral, fore and aft drift, of ground obstacles and sloping/uneven terrain in the landing zone that could induce dynamic roll-over, and of potential collisions with other nearby aircraft and building structures. The desired system will be applicable to other DVE (fog, rain, snow). Landing guidance may come from conventional/modified instrumentation, new human-factored, cognitive primary functional displays, or combination of both.
The system must be able to provide the following information: aircraft rate of descent; absolute height above the ground with accuracy goal of 1 foot (when below 50 feet altitude); and drift velocity with accuracy goal of 1 knot and drift direction accuracy goal of 1 degree. The system will also include sensing and display elements that will be able to be fully integrated in the UH-60 Black Hawk platform. It is highly desirable that methods for incorporating the Sandblaster capability into UH-60A/L/M models and other legacy military helicopters,
be identified.
As a baseline, full-scale test data on dust concentrations and particle size distributions of the brownout dust clouds for UH-60 class helicopters (and other legacy helicopters) have been measured at the Yuma Test Center dust range.
EVALUATION
DARPA will conduct range tests and Sandblaster system effectiveness evaluations at government facilities, with appropriate test support from the Sandblaster system developers. Initial assessments of system effectiveness will be evaluated in a government specified flight simulator (such as the NASA Ames VMS) and in the U.S. Army JUH-60A RASCAL test bed. These evaluations will be based on pilot-in-the-loop handling quality ratings (Cooper Harper rating scale) when performing brownout approach and landing as well as other maneuvers (e.g., hover, lateral reposition).
System sensor’s ability to measure and display aircraft rate of descent; absolute height above the ground and drift velocity will be tested. See-through, see-and-remember, and/or synthetic vision estimates of landing zone ground slopes, and recognition and location of dangerous obstacles (such as walls, buildings, ditches, berms, rocks, stumps, fences, posts, power poles, animals, people, other aircraft) will be tested and assessed on the Yuma dust range.
Novel approaches to using cognitive and physiological assessment of pilot workload may be included in the system evaluation to increase our understanding of pilot reactions to the landing environment. Task performance time, sink rate at touchdown, lateral velocity at touchdown (ideally zero), forward velocity at touchdown (ideally minimal) and course/altitude profile deviation during approach will be measured. It is highly desirable that the system provide the desired situational awareness in degraded visual environments other than brownout as well. Rather than using military helicopters and pilots, DARPA may elect to conduct field evaluations of an installed Sandblaster system in a commercial helicopter under brownout conditions using contractor pilots at the Yuma Test Center dust range.
Previous DARPA-sponsored work on Sandblaster has mainly consisted of a highly-productive science-based experiment and analysis effort to characterize the technical factors and phenomenology of the brownout problem, to provide a basis for see-through sensor development. These experiments have included full-scale dust cloud characterization measurements at the Yuma dust range, using six different types of rotary wing aircraft, in which cloud patterns, dimensions, airborne dust density and particle size distributions.
The Yuma tests were followed by laboratory experiments (jointly sponsored by DARPA and the U.S. Air Force Research Laboratory (AFRL)) to measure the effect of these airborne concentrations and size distributions on EO, IR, LADAR and millimeter wave sensors. Additional AFRL work has also addressed the see-and-remember approach, which is a type of synthetic vision technology based on image data collected just prior to brownout onset. ♦