Lunar Landing Research Vehicle—the book
Unconventional, Contrary, and Ugly: the Lunar Landing Research Vehicle, Gene J. Matranga, C. Wayne Ottinger and Calvin R. Jarvis with D. Christian Gelzer, 2005, Monographs in Aerospace History #35/NASA SP-2004-4535, 220 pp.
Landing on the moon seems so simple. Gravity about 17% of Earth so less engine power and fuel. No air resistance, so no need for streamlining the design. No other “air” traffic” so no need for even looking about. Just flying to a landing with a machine designed for just that one landing–once.
All the above is correct.
But it had to fly on Earth first—hence the birth of the Lunar Landing Research Vehicle (LLRV) leading to the Lunar Landing Training Vehicle (LLTV)–see this post for images of the LLRV).
That is when the reality, the details and the physics set in.
Unconventional, Contrary, and Ugly: the Lunar Landing Research Vehicle explains the latent though significant physics which required discovery and understanding. The multitude of people who came to be involved became a management story of itself—working for the common as well as outstanding goal to put people on the moon and bring them safely back.
The authors were more than intimately involved and write details that are likely not literalized elsewhere. Their understanding and writing abilities combine synergistically for a book to be treasured by history buffs as well as those who study practical physics or managing large teams of people.
The apparent problem of simulating moon gravity was addressed by a jet engine providing about 83% of the thrust required in flight which left the rocket power to fly the craft. Fuel flow to the engine produced a yawing motion, side thruster propellant had to be balanced as it was consumed asymmetrically which increased the yaw and decreased pilot authority. Weber had to design an especially light weight zero-zero ejection seat and this is explained in detail. These seats saved three lives over three crashes so their design is iconic. Pioneering is expensive after all is said and done. Unlike other designs, these seats required each pilot’s weight, density and center-of-gravity to be calculated in order to custom make seat cushions for each pilot. Subtle physics which made the difference between life and death three times.
Flying the LLRV was much unlike a helicopter, though it would seem to be similar, since it required as much as 28º forward tilt to produce motion where a helicopter demand a mere 5º to come out of hover. All the while 4º tilt was needed to compensate for aerodynamic drag. Helicopters fly and the LLRV opposed gravity with thrust alone. Using a jet engine to counter most of Earth’s gravity was complicated as well since fuel burn reduced the LLRV’s weight during flight—so the main engine thrust had to be reduced commensurately. But how to accomplish this when the LLRV could not be weighed on a scale in real time? The clever engineering answer—accelerometers. The temperature of the hydraulic fluid also required its own calculation. These amazing insights and so much more are contained within this publication. Equally amazing is this publication is free to download here as a PDF. This story of the people who united to create a paradigm in this unique flying machine is captivating in its breadth and excitement as are the physics which had to be discovered and met.