Exhaust plumes emanating from smoke stacks at power plants or other industrial facilities can have adverse impacts on local aviation during periods of calm winds. Adverse impacts can be exacerbated if the temperature is low or the atmosphere is unstable. While low oxygen concentrations and elevated temperatures inside the...

Rotorcraft typically operate near the ground throughout the duration of the operation. For this reason, military rotorcraft are vulnerable to acoustic detection, and public acceptance of civil rotorcraft is limited by annoyance caused by rotor noise radiation. The purpose of this...

Electrical power lines pose a serious crash hazard to helicopters and other air-based vehicles, especially small aerial vehicles such as unmanned aircraft systems (UAS). This is because power lines are so widespread, hard to see, and strung at roughly the same height above the ground at...

Currently, APET includes a modified version of the Rotorcraft Noise Model (RNM, version 7). It also includes the newly developed Spectral Attenuation Method (SAM), which contains the Ray Tracing Program (RTP) and two versions of a Green's Function Parabolic Equation (GFPE) code. The third component...

NASA’s Jet Propulsion Laboratory (JPL) has developed a probabilistic algorithm for hazard detection and avoidance (HDA) that robustly handles sensor noise. Conventional surface characterization methods use fixed hazard thresholds to determine hazardous...

Historically, parachutes have been load-tested by various methods including release from an aircraft, deploying in a wind tunnel, dragging through water, and shooting out of an air cannon. Each type of testing has its own advantages and drawbacks. Due to the loading mechanics particular to parachutes...

Micro aerial vehicles (MAVs) are agile and have unstable flight dynamics. They require a failsafe method to be navigated through areas even without GPS coverage. The approach of this work is to use only the feature matches between two consecutive images, i.e. optical flow...

A safe and precise landing system for Mars will match features seen in descent imagery against a map constructed from orbital imagery. The spacecraft attitude and altitude are known, but lateral position is known only poorly. From attitude and altitude, one can generate a mapping (homography) that...

Accurate measurements of airflow angles are among the most expensive and difficult to obtain in flight testing because of the complexity of the airflow near the aircraft and the consequent need to carefully mount and calibrate the sensors. A novel technique was developed...