Space Travel

Part 5 - Apollo 8, Nasa's boldest mission

It was the early evening of January 27th 1967.  Gus Grissom, Ed White and Roger Chaffee had been in the Apollo capsule for six and a half hours conducting a full scale dress rehearsal of the Apollo 1 launch, due in 3 weeks time, when the fire started. This was no normal fire it was a fire in 100% oxygen 1 atm. environment, such fires burn very hot and they are almost impossible to extinguish. The astronauts were dead very quickly.

Although playing catch-up in the first half of the decade, the US goal of getting a man on the moon before 1970 (and before the Ruskies) was starting to look good up to that point. The Russians still had a timetable that would put men on the moon in September 1968 (not that the Americans knew that) – but whilst the American programme had started to gain serious momentum, the Russians had suffered a major loss the year before when Sergei Korolev, the brilliant Soviet Rocket designer, had died.

The Apollo command and service module was being built by North American Aviation (NAA), unlike the Gemini and Mercury capsules that were built by McDonnell Aircraft. North American were probably chosen for political reasons by NASA (didn’t want to be seen to favour one company) – and NAA weren’t making a great job if it. Frank Borman, a NASA astronaut, was sent to their production plant to oversee the design and construction and found a number of issues including technicians standing on the existing wiring during manufacture and even more bizarrely deciding to implement the control joystick with opposite sense to those used in all aircraft and all other spacecraft. But it wasn’t just the command and service modules that were causing delays the other equipment was too: The Saturn V booster that was to make the trip to the moon possible had been suffering lots of delays (Apollo 1 was to launch on a much smaller Saturn I) – in particular problems with combustion instability in the giant F1 engines were holding it up. The Lunar module (LEM) was also suffering repeated delays and problems in particular in trying to get the weight down.

Some relief was provided when ten months after the Apollo 1 disaster the next launch in the series, Apollo 4 was a success. Apollo 2 & 3 having been cancelled Apollo 4 was the unmanned first launch of a Saturn V.

NASA folk started to believe again as the Apollo Capsule was significantly redesigned; including a quicker opening hatch – but more importantly, a thorough removal of anything combustible from the cabin (e.g. Velcro on the flight suits) and a 60/40 Oxygen/Nitrogen mix rather than pure Oxygen.

Despondency returned though in 1968 when in April the second launch of a Saturn V on the (again unmanned) Apollo 6 mission when the Saturn V experienced problems in all three stages – in particular a dramatic pogo-ing on stage 1 that would probably have destroyed the delicate LEM if one had been aboard. As it was, two of the second stage engines failed to operate properly due to damage from the pogo-ing made worse by the fact that the wiring between the two engines had, at least in part been cross-connected meaning they didn’t properly respond. To add to the problems the third stage engine failed to relight when it was needed to adjust the Orbit

To add to the depression, the very same day as Apollo 6 launched, a CIA report came from Russia stating that the Soviets could probably do a lunar orbit mission in the next few months and do a lunar landing in 1969.

As summer turned to autumn, George Low the manager of the Apollo progamme sat on the beach on a family holiday pondering the problems the agency had – in particular the delays in the LEM development –  and how those delays  would mean the incremental missions NASA were planning would push out into 1970. This would mean a lunar landing missed the deadline set by JFK and probably behind the soviets. He came back from holiday to propose to a couple of his colleagues a dramatic change in the schedule – instead of making apollo 8 a conservative low earth orbit test with the LEM, send it around the moon without a LEM and do that in just 16 weeks time (16 weeks because that was the best time for such a mission given lunar position for having proposed landing sights sunlit).

This was incredibly bold; bold because the Saturn V had only flown twice and only with a 50/50 success rate and bold because neither it nor the Apollo capsule had ever flown a manned flight at that moment, bold because preparation for any manned space flight normally took much longer than 16 weeks, bold because any failure of the Apollo CSM engine would leave three dead astronauts orbiting the moon forever, bold because no one had attempted the type of skip-re-entry that was required to slow the craft down on return to earth – but above all bold because no human had ever left earth orbit before.

Five days after his return from holiday Low had managed to persuade his colleagues that this was a good idea and Frank Borman was summoned from the simulator in California to a meeting with Deke Slayton where he was asked if he and his crew would fly the mission Borman was a military man with a strong sense of duty (it is safe to say he would not have locked himself in his car during the westminster attack), he agreed immediately.

He and his crew of Jim Lovell and Bill Anders then started hectic preparations for the flight. Apollo 7 was launched next month on the smaller Saturn 1 rocket, so that at least the Apollo had got some manned crew time. Apollo 7 went well apart from a minor crew mutiny (they refused to don spacesuits for re-entry and as a result none of them ever flew again).

During the preparations for the flight of Apollo 8 Marilyn Lovell privately asked Chris Kraft (director of Flight Operations) what he honestly thought Frank’s survival chances were after a pause Kraft replied “I think about 50/50”.

Ross, Going Postal
Apollo 8 on the launchpad

Apollo 8 and the first manned flight on a Saturn V launched on December the 21st1968. Three hours after launch the third stage engine was fired again on a burn to take the astronauts to the moon. They became the fastest humans ever at that point (25,500mph) and hardly had the burn finished when they broke the previous altitude record which at the time stood at only 853 miles.

The trip to the moon took three days and required celestial navigation that seems incredibly primitive – effectively the same as 18thcentury sailors they take sightings of known stars and measure angles – i.e. they use a sextant. Here is Jim Lovell aboard Apollo 8 taking a position reading from the Apollo sextant…

Ross, Going Postal
Apollo Sextant

Amazingly this is still the method used (albeit more automatically) on interplanatery space craft today. Jim lovell learnt a pro-tip on this trip though, one that would be really useful experience for his later flight on Apollo 13 – when travelling between the Earth and the moon don’t mis-enter the nav command to the spacecraft and tell it that its really back on the launchpad. That sinking feeling as you press the ENTER key and know you shouldn’t have! He had to re-align the guidance computer from first principles as a result.

When they arrived at the moon they had to burn their SPS engine on the Apollo spacecraft  first to drop them into orbit and then to circularise the orbit.

They spent the next 20 hours photographing the moon – and famously the earth in the much used picture called Earthrise – it wasn’t just the picture it was the word “earthrise” used on the TV broadcast, practically no-one outside of science fiction readers had ever heard such a word.

Ross, Going Postal
Earthrise

Yes BapH and Wolf we know you think this is CGI no need to tell us again.

After 20 hours orbiting the moon they had to burn again to get them home – a burn that everyone was anxious about. In some ways more difficult was the return to earth itself as the craft was travelling a lot faster than regular orbital craft returns when it hit the atmosphere. The craft had to fly a really odd profile, never attempted before by NASA, called a skip re-entry. The spacecraft entered the atmosphere and then after starting to slow had to go BACK UP for a bit to cool off and then a second re-entry, this was tricky as the spacecraft had dumped its engine at this point and neither did it have any aerodynamic control surfaces – it achieved this trick by having a slightly odd CofG and rotating by 180 degrees to change the angle of attack of the craft into the airflow.

The craft landed in the pacific and after a delay (for it to get light – NASA was genuinely worried about a shark attack!) the crew were recovered to the USS Yorktown. The Astronauts became the setters of many records including –

  • First to leave earth orbit
  • First to fly on the Saturn V
  • First to enter Lunar orbit
  • Fastest humans
  • Fastest re-entry
  • Furthest humans from earth (beating the old record by about a factor of 250)

So although Apollo 11 and Apollo 13 got much attention in subsequent years – I think this mission of all the Apollo missions was the boldest step and biggest gamble they took.
 

© Ross 2018
 

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