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A new flight research vehicle, the Rotorcraft-Aircrew Systems Concepts Airborne Laboratory (RASCAL), is being developed by the U.S. Army and NASA at Ames Research Center. The requirements for this new facility stem from a perception of rotorcraft system technology requirements for the next decade together with operational experience with the Boeing Vertol CH-47B research helicopter that was operated as an in-flight simulator at Ames during the past 10 years. Accordingly, both the principal design features of the CH-47B variable-stability system and the flight-control and cockpit-display programs that were conducted using this aircraft at Ames are reviewed. Another U.S. Army helicopter, a Sikorsky UH-60A Black Hawk, has been selected as the baseline vehicle for the RASCAL. The research programs that influence the design of the RASCAL are summarized, and the resultant requirements for the RASCAL research system are described.

Future aircraft cockpits may be equipped with both collision avoidance systems and cockpit traffic situation displays. This paper summarizes a series of experiments investigating a pilot's ability to make a variety of traffic related decisions with a traffic display. Some of the key findings were: Pilots were not able to accurately judge the future position of an aircraft unless the display contained predictor symbols. Pilots' subjective judgements of threat were inversely proportional to time to closest approach but generally were not sensitive to small changes of other parameters of the encounter. When pilots were asked to make avoidance maneuvers based solely on the traffic display, they began their maneuvers well before a CAS advisory would have been triggered. Provided sufficient time was available, pilots preferred horizontal avoidance maneuvers.

Piloted, moving-base simulations have been performed in the evaluation of several VTOL control system concepts during landings on a destroyer in adverse weather conditions. All the systems incorporated attitude control augmentation; most systems incorporated various types of translational control augmentation implemented either through aircraft attitude or, more directly, through the propulsion system (thrust magnitude and deflection). Only one of the control systems failed to provide satisfactory handling qualities in calm seas. Acceptable handling qualities in sea state 6 seem to require a system with control augmentation in all translational degrees of freedom.

The first step in verifying the design of the rodent Research Animal Holding Facility (RAHF) as a barrier to environmental contaminants was successfully completed at NASA Ames Research Center (ARC) during a 12-day bio-compatibility test. Environmental contaminants considered were solid particulates, microorganisms, ammonia, and odor-producing organics. The 12-day test at ARC was conducted in August 1988, and was designed to verify that the rodent RAHF system would adequately support and maintain animal specimens during normal system operations. Additional objectives of this test were to demonstrate that: 1) typical particulate debris produced by the animal, i.e., feces and food bar crumbs, would be captured by the system; 2) microorganisms would be contained; and 3) the passage of odor-producing organics and ammonia generated by the animals was adequately controlled. In addition, the amount of carbon dioxide exhausted by the RAHF system was to be quantified.

An integrated engineering breadboard subsystem for the recovery of potable water from untreated urine was designed, fabricated and tested. It was fabricated from commercially available components without emphasis on weight, volume and power requirement optimization. Optimizing these parameters would make this process competitive with other spacecraft water recovery systems. Unlike other phase change systems, this process is based on the catalytic oxidation at elevated temperatures of ammonia and volatile hydrocarbons to innocuous products; therefore, no urine pretreatment is required. The testing program consisted of parametric tests, one month of daily tests, and a continuous run of 165 hours. The recovered water is low in ammonia, hydrocarbons and conductivity and requires only adjustment of its pH to meet drinking water standards.