Bailey, Stephen — Page 2 | Engineering Papers

NASA NTRS1992

Artemis: Common lunar lander project status

Information is given in viewgraph form on the Artemis Common Lunar Lander project status. The plans are to start the Space Exploration Initiative (SEI) with lunar robotic missions that can demonstrate the NASA cultural change and provide a catalyst for human exploration of the moon and Mars. The Artemis Common Lunar Lander Concept developed by the Johnson Space Center (JSC) has been accepted as the centerpiece of this lunar robotic exploration program. Topics covered include the anticipated program structure, a concept overview, lander value as a function of payload mass, the approach of the JSC in-house study, an example launch vehicle packaging concept, and the use of the Delta 2 launch vehicle.

Bailey, Stephen↗

NASA NTRS1991

A Common Lunar Lander (CLL) for the Space Exploration Initiative

Information is given in viewgraph form on the Artemis project, a plan to establish a permanent base on the Moon. Information includes a summary of past and future events, the program rationale, a summary of potential payloads, the physical characteristics of experiments, sketches of equipment, design study objectives, and details of such payloads as the Geophysical Station Network, teleoperated rovers, astronomical telescopes, a Moon-Earth radio interferometer, very low frequency radio antennas, the Lunar Polar Crater Telescope, Lunar Resource Utilization Experiments, and biological experiments.

Bailey, Stephen↗

NASA NTRS1990

A GNM mission and system design proposal

Here, the author takes an advocacy position for the proposed Mars Global Network Mission (GNM); it is not intended to be an objective review, although both pros and cons are presented in summary. The mission consists of launches from earth in the '96, '98, and '01 opportunities on Delta-class launch vehicles (approx. 1000 kg injected to Mars in 8 to 10 ft diameter shroud). The trans Mars boost stage injects a stack of small independent, aeroshelled spacecraft. The stack separates from the boost stage and each rigid (as opposed to deployable) aeroshell flies to Mars on its own, performing midcourse maneuvers as necessary. Each spacecraft flies a unique trajectory which is targeted to achieve approach atmospheric interface at the desired latitude and lighting conditions; arrival times may vary by a month or more. A direct entry is performed, there is no propulsive orbit capture. The aeroshelled rough-landers are targeted to achieve a desired attitude and entry flight path angle, and then follow a passive ballistic trajectory until terminal descent. Based on sensed acceleration (integrated to deduce altitude), the aft aeroshell skirt is jettisoned; a short later a supersonic parachute is deployed. The ballistic coefficient of the parachute is sized to achieve terminal velocity at about 8 km. However the parachute is not deployed until a few Km above the surface to minimize wind-induced drift. The nose cap descent imaging begins, a laser altimeter also measures true altitude. Based on range and range rate to the surface, the parachute is jettisoned and the lander uses descent engines to achieve touchdown velocity. A contact sensor shuts down the motors to avoid cratering, and the lander rough-lands at less than 5 m/sec. The remaining aeroshell and a deployable bladder attenuate landing loads and minimize the possibility of tip over. Science instruments are deployed and activated, and the network is established.

Bailey, Stephen↗