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Timmons, J. D.

Publications and source records attributed to Timmons, J. D..

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Viking balloon launched decelerator tests

The Viking Project utilized a 16.2M diameter disk-gap-band parachute to successfully land two research spacecraft on the surface of Mars during the summer of 1976. Unique specifications were imposed upon both the decelerator system and the balloon systems which were employed to provide a high altitude launch platform for a rocket powered test vehicle. The performance and stability of the balloon system and the predictability of the test vehicle trajectory offered interesting challenges. Descriptions of the development work for suitable materials, fabrication techniques and peculiarities, and testing requirements for both the decelerator and balloon systems will be presented.

Timmons, J. D.↗
NASA NTRS1973

Qualification flight tests of the Viking decelerator system.

The Balloon Launched Decelerator Test (BLDT) series conducted at White Sands Missile Range (WSMR) during July and August of 1972 flight qualified the NASA Viking '75 decelerator system at conditions bracketing those expected for Mars. This paper discusses the decelerator system design requiremnts, compares the test results with prior work, and discusses significant considerations leading to successful qualification in earth's atmosphere. The Viking decelerator system consists of a single-stage mortar-deployed 53-foot nominal diameter disk-gap-band parachute. Full-scale parachutes were deployed behind a full-scale simulated Viking vehicle at Mach numbers from 0.47 to 2.18 and dynamic pressures from 6.9 to 14.6 psf. Analyses show that the system is qualified with sufficient margin to perform successfully for the Viking mission.

Moog, R. D.↗