As a member of the Government-Industry team that helped launch Apollo 11 40-years ago today I can’t help but write something about that day and the mission.
I was fortunate enough to be there, 3 ½ miles away from the Saturn 5 rocket, to witness the launch of the first men to walk on the moon. Why 3 ½ miles you may ask? For safety reasons NASA cordoned off a blast zone based upon the explosive energy in the launch vehicle. The calculations showed that an explosion of the rocket on the pad could throw 100 lb pieces of shrapnel 3 miles. The VIP stands were set at 3 ½ miles away.
One remarkable thing about that launch was that it went off perfectly, on time and with no glitches. Usually there are some minor things that go wrong but this launch left everyone waiting for that other shoe to drop.
The Apollo computers were considered very powerful at the time yet they had less processing power than today’s cell phones.
I take it for granted that people know the details of the moon mission simply because I do but then I remember it happened 40 years ago and most people around today don’t. So here is a little technical rundown of the Apollo 11 mission.
The launch itself was exciting and scary at the same time. The Saturn 5 Launch Vehicles engines are fired and the rocket is held in place for 3 seconds while full thrust develops. . The 5 engines are actually fired 0.3 seconds apart to lessen the acoustic vibration experienced by the astronauts and the vehicle. It takes the rocket a full 11 seconds to clear the launch tower. Engine failure during this phase would likely result in loss of the crew.
There were 3 ways the astronauts could escape potential disaster. If they were faced with a potential explosion before lift-off they could exit the Apollo capsule, run along the swing arm and either jump into an escape slide that brought them to a bunker under the launch pad or they could use the slide wire that delivered them to a protected bunker beside the launch pad. After lift-off the Apollo capsule had an escape rocket on it to lift the capsule up and away so it could parachute to safety.
After reaching orbit the next big event is translunar injection. The 3rd stage of the rocket provides the energy to send the vehicle away from earth orbit in such a manner that the Apollo capsule will encounter the moon with the proper orbital plane alignment for the Lander to reach the landing site. The astronauts are now traveling at 24,000 mph.
The translunar coast takes 3 days to cover the 240,000 miles to the moon. During this period the Command and Service Module ( CSM ) separates from the 3rd stage, rotates, and couples with the Lunar Module (LM) and backs away from the 3rd stage . Rendezvous and docking techniques were first demonstrated by the earlier Gemini Program to prepare for the moon mission.
When the capsule reaches the moon it must fire it’s rockets the enter a lunar orbit. Interestingly this burn occurs when the astronauts are out of communication with the earth. For 45 minutes on each lunar orbit there is no signal from the craft. This provides for a period of high anxiety at mission control in that grey area where the signal should appear again and great rejoicing when all is well.
Then comes the big event. The LM with 2 guys in it separates from the CSM and begins its final descent to the landing site. We learned later that the LM was sounding 2 program alarms starting about 7 miles above the moon. The astronauts were assured it was OK although the cause wasn’t learned until much later. The problem occurred because they had the unneeded rendezvous radar operating during descent and it was overloading the computer.
Then at about 300 ft Neil Armstrong noted the lander was heading for an enormous crater surrounded by boulders. He very nearly exhausted the fuel supply maneuvering to a smoother area to land. It was later determined that the cabin of the orbiter wasn’t fully depressurized when the LM separated from it and the effect (sort of like popping a cork on champagne) caused the LM to land 4 miles away from the desired landing site.
Everyone’s familiar with the landing and moon walks but you may not know that Neil landed so softly that the landing struts didn’t depress. His one small step was really pretty big. He had to jump 3 ½ feet from the ladder to the surface. I almost forgot. Once landed the astronauts were supposed to stay inside and take a nap—right. Do you think you could nap when you were the first ones on the moon? Theey did stay inside--I don't know if they slept.
Some other interesting facts: planting the flag proved more difficult than expected. The surface of the moon was a lot harder than they thought. The flag (made by Sears) was just barely planted. Buzz had to make sure he left the LM door unlocked when he came out. There is no outer handle on the door and AAA doesn’t cover lockouts on the moon. We don’t have Neil’s boots from the first moonwalk. Weight considerations and fears of dust contamination resulted in them leaving their boots behind.
After about 22 hours on the moon it was time to go. During this time astronaut Collins was orbiting the moon alone and experiencing those 45 minute blackout periods when he was out of touch with all of mankind. Could you be any more alone? The top part of the LM ascends by firing its rocket motor leaving the base and legs on the moon (along with the boots).
Back in lunar orbit the crucial rendezvous and docking is executed flawlessly. Before leaving lunar orbit the LM is ejected and left in lunar orbit. The CSM then fires its engine for trans-earth injection and the long ride home.
Before entering Earth’s atmosphere the Service Module is separated leaving only the Apollo Command Module to return to earth. These were the days of splashdown in the water and pickup by an aircraft carrier. Reentry angle must be controlled within a tenth of a degree for success. By this time we were getting pretty good precision in our landings and the capsules were usually spotted while they were still in the air with their parachutes. In the early days it was rare to see one with parachutes.
The astronauts were put in isolation after returning to assure they didn’t bring back any unknown dangerous moonbugs.
Whew! That’s enough for this year.
Back on earth today I did get the bed headboard and footboard assembled. We also got a paint color tab from Lowe’s to make sure Bistro White is the correct color. I matched it to the bed rails I made 2 years ago and it is the correct color. The bed should be finished this weekend.