Eva1 Deploying The Rover And The First Traverse

The two astronauts got an early wakeup call from Houston at 115.5 hours into the mission. They checked out a minor pressure drop in the descent stage oxygen tank,

On the right side of the Control and Display Console was affixed a plaque identifying the men who brought the LRV to the Moon. It reads: "Man's First Wheels on the Moon. Delivered by Falcon. July 20, 1971'', with the signatures and names of David R. Scott, Alfred P. Worden, and James B. Irwin (NASA)

On the right side of the Control and Display Console was affixed a plaque identifying the men who brought the LRV to the Moon. It reads: "Man's First Wheels on the Moon. Delivered by Falcon. July 20, 1971'', with the signatures and names of David R. Scott, Alfred P. Worden, and James B. Irwin (NASA)

and went through their check list for the morning in preparation for their first EVA. They also had breakfast. It took over four hours to complete all the preparations but once their suits were on, they depressurized the cabin, opened the hatch, and Scott made his way out to the Lunar Module's "porch." He activated the Lunar Surface TV camera and CapCom Dr. Joseph P. Allen reported getting a good picture. The audience for the images being beamed back to Earth was the largest since Apollo 11. Also watching with the greatest of interest was Saverio Morea and his team in Huntsville, the entire Boeing LRV team and their subcontractors, and Dr. Wernher von Braun, who was witnessing yet another piece of the Apollo lunar exploration puzzle being put into place. The LRV was really the focus of attention. The entire mission, in fact, hinged upon it. It had to perform or Scott and Irwin would have to resort to the walking traverse plan. Scott pulled a D-handle to retract the three pins holding the LRV to its attachment points, in preparation for its deployment. A spring-loaded push-off rod moved the folded rover away from the LM by about 12 cm until it was stopped by two deployment cables. Scott descended the ladder to the Lunar Module's footpad and then stepped onto the lunar surface.

''Okay, Houston,'' Scott radioed to Mission Control, ''As I stand out here in the wonders of the unknown at Hadley, I sort of realize there's a fundamental truth to our nature. Man must explore. And this is exploration at its greatest. Well, I see why we're in a tilt ... There's so much hummocky ground around here [and] we're on a slope of probably ten degrees. And the left-rear foot pad is probably about two feet lower than the right-rear foot pad. And the left-front's a little low too. But the LM looks like it's in good shape. The Rover's in good shape.''

Scott's last comment on the condition of the LRV produced a collective sigh from the rover team on Earth after the Falcon's hard landing, but there were still concerns about what effect the landing may have had on the condition of the rover's many systems. No one would know the condition of the batteries until the vehicle was unfolded, its chassis locked in position and then powered up. Irwin soon joined his colleague on the surface of the Moon. In order to view the rover's deployment, Scott set up the Ground-Commanded Television Assembly (GCTA) tripod roughly ten meters away from the LM, then moved the TV camera from its place in the Stowage Mount Assembly of the MESA to the tripod. Scott mentioned to Houston that pointing the TV camera toward the LM would have it looking almost directly into the Sun, so he moved the tripod and camera into Falcon's shadow and the problem was solved.

Both astronauts then began deployment procedures, but before doing so, Scott discovered one of the deployment walking hinges was unlatched. Irwin noticed the other was also unlatched and in this condition, the rover would not properly deploy. So the astronauts reset the walking hinges, something they had practiced many times on Earth. Scott and Irwin then walked several meters away from the LM and began pulling on their respective deployment tapes. The rover began its descent. Just past 45 degrees, the rover's rear chassis and wheels deployed, somewhat startling the astronauts. Scott advocated caution as they continued slowly pulling on the tapes but soon the rear wheels were on the surface. Shortly thereafter the front chassis and wheels deployed. Because the LM was at an angle on the lunar surface, the rover was not ideally positioned in this phase of deployment, and Irwin had to pull more than Scott. The two astronauts had to lift the rover and pull it away from the LM to release it from the supporting saddle, but on the Moon, because it weighed a mere /6 of its weight on Earth, both astronauts found it easy to move.

They then continued pulling on the deployment tapes and the LRV settled completely on the surface. Scott and Irwin checked that the chassis locking pins were properly seated and that the instrument and control console was also locked in position. The two men then picked up the rover and turned the front end away from the LM so it would be in position to drive away. Then the toe holds were inserted, the seatbacks and foot rests erected, fender extensions moved and locked into position, seatbelts released, and the docking pins and latches removed from the rover.

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