Engineering topics

Hoang, TY

Publications and source records attributed to Hoang, TY.

3 records

NASA NTRS1994

A real-time algorithm for integrating differential satellite and inertial navigation information during helicopter approach

A real-time, high-rate precision navigation Kalman filter algorithm is developed and analyzed. This Navigation algorithm blends various navigation data collected during terminal area approach of an instrumented helicopter. Navigation data collected include helicopter position and velocity from a global position system in differential mode (DGPS) as well as helicopter velocity and attitude from an inertial navigation system (INS). The goal of the Navigation algorithm is to increase the DGPS accuracy while producing navigational data at the 64 Hertz INS update rate. It is important to note that while the data was post flight processed, the Navigation algorithm was designed for real-time analysis. The design of the Navigation algorithm resulted in a nine-state Kalman filter. The Kalman filter's state matrix contains position, velocity, and velocity bias components. The filter updates positional readings with DGPS position, INS velocity, and velocity bias information. In addition, the filter incorporates a sporadic data rejection scheme. This relatively simple model met and exceeded the ten meter absolute positional requirement. The Navigation algorithm results were compared with truth data derived from a laser tracker. The helicopter flight profile included terminal glideslope angles of 3, 6, and 9 degrees. Two flight segments extracted during each terminal approach were used to evaluate the Navigation algorithm. The first segment recorded small dynamic maneuver in the lateral plane while motion in the vertical plane was recorded by the second segment. The longitudinal, lateral, and vertical averaged positional accuracies for all three glideslope approaches are as follows (mean plus or minus two standard deviations in meters): longitudinal (-0.03 plus or minus 1.41), lateral (-1.29 plus or minus 2.36), and vertical (-0.76 plus or minus 2.05).

Hoang, TY↗

NASA NTRS1992

Preliminary design of nine high speed civil transports

Sixty senior design students at Cal Poly, SLO have completed a year-long project to design the next generation of High Speed Civil Transports (HSCT). The design process was divided up into three distinct phases. The first third of the project was devoted entirely to research into the special problems associated with an HSCT. These included economic viability, airport compatibility, high speed aerodynamics, sonic boom minimization, environmental impact, and structures and materials. The result of this research was the development of nine separate Requests for Proposal (RFP) that outlined reasonable yet challenging design criteria for the aircraft. All were designed to be technically feasible in the year 2015. The next phase of the project divided the sixty students into nine design groups. Each group, with its own RFP, completed a Class 1 preliminary design of an HSCT. The nine configurations varied from conventional double deltas to variable geometry wings to a pivoting oblique wing design. The final phase of the project included a more detailed Class 2 sizing as well as performance and stability and control analysis. Cal Poly, San Luis Obispo presents nine unique solutions to the same problem: that of designing an economically viable, environmentally acceptable, safe and comfortable supersonic transport.

Sandlin, Doral↗

NASA NTRS1991

The Eliminator: A design of a close air support aircraft

The Eliminator is the answer to the need for an affordable, maintainable, survivable, high performance close air support aircraft primarily for the United States, but with possible export sales to foreign customers. The Eliminator is twin turbofan, fixed wing aircraft with high mounted canards and low mounted wings. It is designed for high subsonic cruise and an attack radius of 250 nautical miles. Primarily it would carry 20 500 pound bombs as its main ordnance , but is versatile enough to carry a variety of weapons configurations to perform several different types of missions. It carries state of the art navigation and targeting systems to deliver its payload with pinpoint precision and is designed for maximum survivability of the crew and aircraft for a safe return and quick turnaround. It can operate from fields as short as 1800 ft. with easy maintenance for dispersed operation during hostile situations. It is designed for exceptional maneuverability and could be used in a variety of roles from air-to-air operations to anti-submarine warfare and maritime patrol duties.

Hendrix, Mandy↗