Crew Station Subsystem

The Crew Station Subsystem included the folding seats, seatbelts, folding foot rests, hand controller, arm rest behind the hand controller, inboard and outboard hand holds, toe holds, floor panels, the Control and Display Console (CDC), and the wheel fenders. Much of the Crew Station Subsystem was refined as a result of Air Force KC-135 flights simulating zg -G for astronaut training. The toe holds and hand holds in particular were essential in allowing the astronauts to properly ingress and egress the rover during these flights. The folding seats, inspired by aluminum beach chairs, were lightweight and folded into a compact envelope. Nylon webbing acted as the seating surfaces. The seat bottom could fold up to permit access to the stowage compartments under each seat.

The hand controller was a marvel of multi-function operation. The design of the hand controller was initially conceived as a pistol grip, and remained so well into the

The LRV was a complex spacecraft, as this illustration shows. (NASA)

LRV development program. However, astronauts John Young and Charlie Duke pointed out to Boeing and MSFC that the vertical pistol grip design was extremely difficult to use in a pressurized suit. The subtle movements of the wrist required to accomplish steering, accelerating and braking could not be achieved with desired results.

"We worked with the Marshall Space Flight guys on the way the hand controller worked,'' said Capt. John Young during an interview with this author in 2003. "They had designed it so that you moved it like a control stick in yaw with your wrist. In a pressure suit, you couldn't move your wrist a lot. The wrist would be so tired you wouldn't be able to drive after two or three minutes.''

A late design change ordered just months before delivery of the first flight unit resulted in the amended horizontal grip that the astronaut could rest his hand on and which allowed him to use his forearm to perform the LRV functions. Inputs from the hand controller were sent to the Drive Control Electronics located in the forward part of the LRV. These interpreted the mechanical movements of the hand controller into the appropriate signals to change speed or direction, or to apply braking. Moving the hand controller progressively from its spring-loaded central position resulted in greater acceleration or steering angle. Pivoting the hand controller either left or right beyond a half-degree would commence steering. The hand controller could pivot nine degrees either left or right before encountering a soft-stop and progressive resistance to get ever-greater steering angles. Moving the controller rearward from its central position applied the braking action and moving it rearward

7 to 8 cm applied the parking brake. This could be released by moving the controller hard left. Reverse was achieved by the astronaut pushing up on a knob just below the grip and moving the controller rearward.

The Control and Display Console was the nerve center of the LRV. The panel was divided into two main sections. The upper section contained the navigation heading, speed and vehicle attitude information, the navigation gyro torquing and the system reset button; the lower section contained vehicle electrical power controls for batteries, drive and steering controls, and the systems temperature indicators. All vehicle information visible to the astronauts would be radioed in real-time to Mission Control. On top of the CDC was the Sun Shadow Device, which helped to determine the LRV heading with respect to the Sun and worked in conjunction with the directional gyro to indicate the LRV position for the navigation system. Visibility in the harshest conditions was vital, either in shadow or direct sunlight, so the panel itself was black with panel markings irradiated with promethium 147.

The fenders were vital to controlling dust, as tests had proved. Due to the compact envelope of the folded LRV, the front and rear wheels pressed against each other when stowed in the LM. Sliding fender extensions were designed to permit this contact and these were moved by the astronaut along their mounting rails and locked into their fully extended position after the rover was deployed on the Moon. There is an interesting story regarding details of the fender design. Eric Jones, respected author of the online Apollo Lunar Surface Journal, was contacted by Bill Kimsey, who was an engineer with Boeing during the Apollo years. He was closely involved with the design of certain aspects of the LRV as presented in Boeing's proposal to MSFC.

"There were quite a few of us sent from New Orleans to Huntsville to work on the proposal,'' Kimsey told Jones for the ALSJ. "One of the other fellows, Waine Borne, and I had been working together from 1961. We had gotten to be good friends. We both had Model A Fords that we had restored. The Model A has beads around the fenders. I was joking with Waine and drew a bead on the fenders of the Rover. The project manager asked me why I put the bead on the fender and I told him it was to stiffen the fender. The bead remained on the fender. Now it's sitting on the Moon. It is the same width as a Model A Ford. No one but the two of us really knew the story.''

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