Monday, October 18, 2010

A Little Joe II for those who hate to build towers

Under a General Dynamics/NASA proposal, the Little Joe II/Lunar Excursion Module (LEM) would have boosted an Apollo LEM to close to 200,000' where the descent engines could be tested in near vacuum and zero-G conditions.  This interesting configuration featured an interesting, bulbous payload section and, obviously, no escape tower.  The LJ II/LEM was wind tunnel tested with two different nose shrouds as shown in the attached diagram [1].  One source [2] indicates that the configuration was proved to be feasible, while another [3] indicates it was found to be unstable without the addition of larger fins.  Either way, the concept was scrapped in favor of a orbital, Saturn 1B-boosted test.  I like fat rockets and this is on my short list of future builds (but, it's been there a long time). More scale data can be found in ref. [4].

[1] Rogers, Charles, Apollo Little Joe II, High Power Rocketry, Vol. 13 No. 6, August 1998, p. 79, 82, 84.
[2] Data and Analysis of an 0.03 Scale Model of a Little Joe II/LEM Configuration (Langley 8-Foot Transonic Pressure Tunnel Test No. 288), Convair Report GDC-63-243, December 1963.
[3] Little Joe II, Encyclopedia Astronautica.
[4] Harris, C. D., Luoma, A. A., Static longitudinal aerodynamic characteristics of a hammerhead-shaped Little Joe II - Lunar module model at Mach 0.30 to 1.2,  NASA-TN-D-4139, Langley Research Center, October 1967.