Monday, February 20, 2012

50 Years Ago Today - Friendship 7 Orbits the Earth! A First for the American Space Program

Mercury Atlas 6 blasts off from LC-14.

by Mark Daymont
Space Center Educator

After several disappointing weather delays and equipment failure postponements, NASA finally had a good day and launched the third mission of the Mercury program. The previous two missions launched Alan Shephard and Gus Grissom on short sub-orbital flights over the Atlantic. The Redstone rocket used on the previous flights were simply not powerful enough to place the Mercury capsule into an orbital flight, so the heavier Atlas ICBM was converted and "man-rated" to lift the astronauts into space.

Launch Complex 14 at Cape Canaveral Air Force Station.

The Mercury-Redstone missions had taken place from Launch Complex 5. With the more powerful Atlas rocket, operations were established at Launch Complex 14. Mission Control was performed from blast-proof domed bunkers near the pad. For this mission, radio ships at sea joined with radio stations around the world to maintain NASA's communications with the orbiting astronaut.

Astronaut Glenn enters the capsule. In the background is "pad leader" Gunther Wendt, overseeing launch tower operations.

John Glenn was a Marine officer who had flown combat missions in World War Two and the Korean War. As a test pilot, he had flown many types of aircraft and set speed records in the F-8U-1 Crusader jet. His backup for this mission was Scott Carpenter, a naval aviator who had served in the Korean War and flew surveillance missions near Soviet installations.

The ride to orbit was a bumpy one, but after the escape tower jettisoned with the booster engines the ride smoothed out. At last the capsule separated and Glenn became the first American to orbit the Earth at 17, 544 miles per hour. Mission Control gave him the positive outlook that he was "go" for seven orbits at least.


In-flight picture of Glenn in the capsule.

During the flight, Glenn reported on his visual range of the Earth' surface, and at one moment was startled to see hundreds of tiny bight objects swarm around the capsule. He described them as like "fireflies" which the press picked up on immediately and speculated about possible life in space. The fireflies would be an object of investigation on the next Mercury flight. In the photo above, you can also see a curved mirror placed on Glenn's chest. This was included so that the camera in the capsule could also see the reflection of the capsule instrument panel. Also during the flight, there were problems with the temperature warming up too much in Glenn's spacesuit. He had to carefully maintain a balance between suit control settings and the temperature settings inside the capsule.

After an orbit, controllers determined a possible problem with the landing bag system. A computer light indicated that the landing cushion bag had deployed. If true, this could have cause problems with the positioning of the heat shield necessary for re-entry. Flight Director Chris Kraft consulted with flight engineers and they determined that Glenn should not eject the retro-rocket pack, attached to the heat shield with metal straps. Jettisoning the pack could cause the heat shield to slip off, and Glenn would be killed as the capsule experienced severe re-entry heat. Mercury pilot Wally Schirra, one of the astronauts yet to fly, was capsule communicator stationed at California, delivered the procedure plan to Glenn, who fully understood the possible danger.


Computer-generated model of Friendship 7 as it would have looked in orbit. The retro-engine pack with its straps visible on the left of the craft. Image by James R. Bassett.

During re-entry, the retro pack heated up and melted. Glowing pieces flew past the window, as Glenn exclaimed that "that's a real fireball outside." Glenn worried at times that he might be seeing pieces of the heat shield melting and falling away, but the heat shield held fine. As scientists would later determine, the landing bag indicator itself had been faulty, and there never was real danger to the craft. But the mission controllers did not know this at the time.

The parachutes opened as expected and Friendship 7 landed in the Atlantic Ocean. Glenn was about 40 miles from the expected landing zone. Not bad for America's first re-entry after orbit. The destroyer USS Noel quickly found glenn and hoisted him and the capsule out of the water.

Glenn would later receive a ticker-tape parade in New York and would received by President Kennedy and given a medal. But stepping out of the capsule onto the deck of the destroyer, his words were "It was hot in there!"

Normally I would have a bunch more NASA photos of the event in this blog. Unfortunately, the NASA image archives are compromised today, perhaps due to unusually high Internet traffic on this very memorable occasion. SO, I've decided to place a few pics from my trip to KSC last year and I'll post more pictures later.


Memorial plaque and sign at LC-14. As the sign points out, all the Mercury-Atlas flights took place from this complex.


At the Mercury Seven Sculpture. This location is located at the entrance road to the launch complex. That's me on the left, and my Uncle John Daymont, who patiently posed with me while the tour bus driver graciously took the picture. The Cape Canaveral AF Base tour is fantastic, but they only do it once per day IF there are no launches that day.


Distant picture of what's left of LC-14. The Atlas rocket would be trucked up the ramp from the right and then tilted into position into a large Gantry tower on the left. Compare this with the LC-14 picture previous.


Control bunker at LC-14. Supposedly blast proof in case the Atlas missile were to explode on the pad. Sometimes they did during testing!

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