Mar 08

Space Rocket History #200 – Luna 15

In February of 1969, the first launch of the Soviet Moon Rocket, the N-1, exploded.  By April, the Soviets still did not have a clear program of subsequent piloted Soyuz fights. In May, the Soviets watched the successful US lunar orbital flight and practice landing of Apollo 10. In June, a Lunar Sample return mission failed when the Block D stage refused to ignite. On July 3rd the second N1 launch failed with a spectacular explosion…

Soviet Luna 15 was designed to take a sample of Lunar soil and return it to Earth

Ye-8 lunar sample return spacecraft – detail of re-entry vehicle
Credit: Mark Wade

Ye-8 Sample Return method

Mar 01

Space Rocket History #199 – The Second Test Flight of the Soviet N1 Moon Rocket

On July 3, 1969, the same month as the the Apollo 11 Moon landing, The Soviet Union made another secret attempt to fly their giant Moon rocket.

N1-5L Rollout to pad. Credit Russia Space Web

Raising N1-5L

Escape system activated for N1-5L. Credit Russian Space Web.

Feb 22

Space Rocket History #198 – Apollo 10 – Snoopy Returns and a Successful Dress Rehearsal

“Hey, Apollo – Houston, this is Apollo 10. Look, I know you ran some studies, but by golly, we can see Snoopy, and he isn’t too far away! He’s catching up with us. Can you talk to the FIDOS? He’s right down below us. We can occasionally see him tumbling end-over-end down below there, and he’s coming in closer each pass. That’s Snoopy’s descent stage. We can see him right down below us now, and he’s right – I thought he was a little out-of-plane, but now he’s looking more in-plane with us.” Tom Stafford Apollo 10

Relative Orbits of the Command Module and the Descent Stage

Cernan, Stafford & Young arrive on the Carrier USS Princeton

Apollo 10 Command Module at the Science Museum in London

Feb 15

Space Rocket History #197 – Apollo 10 – Ascent Stage Rendezvous, Docking & Jettisoning

As the lunar module approached, Young saw it through his sextant at a distance of 259 kilometers. Stafford and Cernan got a radar lock on the command module shortly after the insertion burn and watched with interest as the instrument measured the dwindling gap between the vehicles and demonstrated the theories of orbital mechanics in actual practice. Cernan especially liked the steady communications that kept both crews aware of what was happening.

Ascent stage of Apollo 10 LM viewed from CM.

Apollo 10 re-docking plan

CM and LM pre-jettison attitude

Feb 08

Space Rocket History #196 – Apollo 10 – Lunar Module Out of Control

The abort system had two basic control modes, “attitude hold” and “automatic.” In automatic, the computer would take over the guidance and start looking for the command module, which was certainly not what the crew intended to do at that moment. While correcting for a minor yaw-rate-gyro disturbance, the astronauts  accidentally switched the spacecraft to the automatic mode, resulting in frantic gyrations.

Apollo Lunar Module

CM viewed from LM after separation

LM Topsy-turvy during staging

Lunar Module Staging Video

Feb 01

Space Rocket History #195 – Apollo 10 – Lunar Module Testing

When Stafford and Cernan were ready for undocking they discovered the Lunar Module had slipped three and a half degrees out of line with the command module at the latching point, possibly due to loose mylar collecting on the docking ring…

Events planned for revolution 12

LM upper hatch locking handle and overhead cabin relief dump valve handle

View of Apollo 10 LM from the CM

Jan 25

Space Rocket History #194 – Apollo 10 – Acquisition of Signal & Lunar Orbit

The six-minute retrograde maneuver seemed interminable, just as it had to Borman’s crew on Apollo 8, but the engine kept firing and the Apollo 10 crew’s confidence in it kept growing. When the engine finally shut down and they were sure that it had done its job, Stafford and Cernan had time to look at the lunar surface. They likened one area to a volcanic site in Arizona. Shortly, Stafford forced his attention back inside the cabin and told his crew-mates that he thought the best thing to say when they got back in radio contact with mission control was, “Houston, tell the earth we have arrived.”

Apollo 10 photographed Sistes 1, 2, & 3

Site 1 was on the eastern side of the Sea of Tranquility

Site 2 was on the southwestern part of the sea

Jan 18

Space Rocket History #193 – Apollo 10 – Coasting to the Moon & Loss of Signal

Stafford, Cernan, and Young were the first Apollo astronauts to be free from illness during the mission, although Cernan experienced a slight vestibular disturbance. Like all their colleagues who had flown before, once they unbuckled from the couches they had a stuffy feeling in their heads. This lasted for 8 to 10 hours for Stafford and Young; Cernan gradually lost the sensation over the next two days.

Apollo 10’s View of Earth seen in MCC

Color TV from Apollo 10

The Patch for Apollo 10