Snatching Victory from the Jaws of Defeat
Commander Guy Larosse and Navigator Malcolm Leyton-Arnold become the first men to ride the Constellation Launch Vehicle when they liftoff from Rainbow Beach on the 31st March. The ascent to orbit is near-perfect and the crew describe the first ECPS burn as a "very smooth ride". They achieve an Earth orbit at 188km.
An intensive period of checks and calibration begins 14 minutes after liftoff. Crew and controllers work together to verify the performance of the ship's main systems while they are in the comparative safety of low Earth orbit. If anything is wrong, they can complete an Earth-orbit backup mission and re-enter at any time. Everything checks out and at T+4:43, ground controllers give the “GO” to proceed with the sequence for translunar injection. Five minutes 22 seconds later, the ECPS guidance system re-ignites the engine. All goes exactly to plan for the next 62 seconds.
The caution alarm sounds on board the spacecraft and alert lights flash in mission control. Fault indicators glow red showing a warning of low hydraulic pressure on the ECPS stage. Working calmly and professionally but with sinking hearts, over the next 50 seconds booster controllers see the pressure steadily drop in the SVV control system; the very same system that failed on CLV-5.
At T+4:50:14, the pressure drops below the red line programmed into the ECPS control system and it responds by shutting down the engine. The spacecraft and the now useless ECPS stage are left in a 188x11,330km orbit around the Earth. The crew are quite safe, their ship is functioning normally, but they are falling over 200,000 miles short of the Moon.
With no reason to stay attached to the ECPS, the crew separate their ship, the “Harmony”, at T+5:18 as originally planned, pitch up and photograph the stage to record any visible damage [there is nothing immediately obvious].
Mission controllers debate what to do next. There is still a glimmer of hope, buried in the details of a backup mission plan. Although Selene 2 was never intended as a landing mission, the VDL carries a full load of fuel and it is quickly calculated that there is enough on board to reach the Moon – if crew and controllers act quickly.
To reach the Moon, the ship would have to complete a loop in its current elliptical orbit, then make an additional TLI burn using the VDL’s on board engine. Another manoeuvre would then be needed once away from the Earth in order to help correct for the later departure time. Three days later, the VDL could perform the lunar orbit insertion manoeuver as planned and the existing flight plan could be resumed. The PROM itself has sufficient fuel on board to return to Earth from lunar orbit, and it was always planned to return from the Moon in this way.
The next opportunity to complete TLI is near the orbit's perigee, which will occur at T+8:26. Two hours of rapid recalculation and checking using the computer facilities at Biscarosse allow controllers to relay the parameters of the new burn up to the crew as their orbit carries them back down towards Earth. Flight medics are concerned that the additional time in high Earth orbit will expose the crew to additional radiation exposure in the Van Allen belts, however the predicted doses are still below overall crew and mission limits.
Having seen the Earth recede and approach in their elliptical orbit, the crew ignite the VDL's engine shortly before perigee. Thirteen minutes of thrusting uses up two-thirds of the VDL's fuel, but succeeds in putting them on a course towards the Moon.
Analysis of the ECPS failure begins immediately the VDL separates, just over 5 hours after liftoff. Booster controllers command a series of valve and actuator movements to try to gather more information on the fault before the stage's batteries run down.
Early press reports surrounding the "failure" of Selene 2 are very mixed, as it soon becomes apparent that the mission will still go to the Moon. Very negative reports in both Soviet and US press are clearly rushed and speculative. British and French media focuses on the efforts being made to resume the mission and praises both the crew's determination and the remarkable "real time computation" being carried out at mission control. TV news in Europe, and to a lesser degree elsewhere, gives continuous (if rather confused) updates on what is happening.
At T+30:06, a course correction is made using the VDL’s main engine, a manoeuvre that completes the process of realigning the trajectory to allow for the Moon being a few hours further along in its orbit than in the original flight plan. It is now possible to revert to something close to the original mission, albeit with a four hour delay added. At T+82hrs the crew make a colour TV transmission showing their ship and the crescent Moon, still 50,000km away from them.
The technical and managerial skills displayed by the drastic changes in the flight plan are not lost on several NASA observers. Many of their confidential reports back to the US state that this supposed "failure" actually shows that mission planning and operations within the Selene Project are of the highest quality, even if the bugs have not yet been worked out of the launchers and hardware. As one NASA flight controller later wrote “If we’d had a problem on the way to the Moon, I hope we would have done as well as these guys…”
The next day, at T+97:50, Harmony disappears behind the Moon, fifteen minutes before the lunar orbit insertion burn is due. When it is complete, only the crew will know if they are in lunar orbit or not. Mission controllers and the rest of the world must wait for the signal to reappear at the right time. Too soon, and the ship may not be in lunar orbit, too late and the ship might be heading for a collision with the surface.
When it appears at exactly the right time, T+98:21:06, Mission Control erupts in cheers and applause. The first Selene crew to orbit the Moon are in a 95x355km orbit, very close to plan. After two revolutions, they fire their engine again to circularise to the 115km orbit they will use for their lunar observation mission.
The first full day in lunar orbit is spent in testing the procedures that will be used for future landings, checking guidance solutions and setting up the systems. Larosse and Leyton-Arnold make the first ever spacewalk conducted outside of Earth orbit, out to Harmony’s external control cockpit. After a "night" in the VDL's Hab, the crew repeat the descent checkout procedures before photographing one of three possible prime landing sites.
Day 3 in orbit includes a third spacewalk to practice the attachment of refuelling lines using a new fitting, designed after the problems encountered on Aurora 11. No actual fuel transfer is planned, but the test of the new lines is a success. Photographs of a second potential landing site are taken later in the day.
The final day around the Moon sees more photographs of sites further west and two interviews, carried live on British and French TV. The PROM is separated from the VDL at T+212:15 and once again, the crew check their navigation systems before using the PROM’s engine to boost themselves onto a course back towards Earth.
A 1.4s correction at T+262:16 is all that is needed to target the ship for re-entry. RM separation is at T+301:38 and the crew feel the first effects of the atmosphere 12 minutes later, travelling at 11,008m/s (just over 24,600mph). They splash down within five miles of the recovery ship under two parachutes to complete a 12 day 14 hour mission.
What could have been a near-total failure was saved by the flexibility and training of the Selene Project’s crews and controllers. Despite the booster failure, the mission proves that the PROM/VDL-C flies as intended, and should be capable of attempting a landing later in the year.
Selene 2
Commander Guy Larosse and Navigator Malcolm Leyton-Arnold become the first men to ride the Constellation Launch Vehicle when they liftoff from Rainbow Beach on the 31st March. The ascent to orbit is near-perfect and the crew describe the first ECPS burn as a "very smooth ride". They achieve an Earth orbit at 188km.
An intensive period of checks and calibration begins 14 minutes after liftoff. Crew and controllers work together to verify the performance of the ship's main systems while they are in the comparative safety of low Earth orbit. If anything is wrong, they can complete an Earth-orbit backup mission and re-enter at any time. Everything checks out and at T+4:43, ground controllers give the “GO” to proceed with the sequence for translunar injection. Five minutes 22 seconds later, the ECPS guidance system re-ignites the engine. All goes exactly to plan for the next 62 seconds.
The caution alarm sounds on board the spacecraft and alert lights flash in mission control. Fault indicators glow red showing a warning of low hydraulic pressure on the ECPS stage. Working calmly and professionally but with sinking hearts, over the next 50 seconds booster controllers see the pressure steadily drop in the SVV control system; the very same system that failed on CLV-5.
At T+4:50:14, the pressure drops below the red line programmed into the ECPS control system and it responds by shutting down the engine. The spacecraft and the now useless ECPS stage are left in a 188x11,330km orbit around the Earth. The crew are quite safe, their ship is functioning normally, but they are falling over 200,000 miles short of the Moon.
With no reason to stay attached to the ECPS, the crew separate their ship, the “Harmony”, at T+5:18 as originally planned, pitch up and photograph the stage to record any visible damage [there is nothing immediately obvious].
Mission controllers debate what to do next. There is still a glimmer of hope, buried in the details of a backup mission plan. Although Selene 2 was never intended as a landing mission, the VDL carries a full load of fuel and it is quickly calculated that there is enough on board to reach the Moon – if crew and controllers act quickly.
To reach the Moon, the ship would have to complete a loop in its current elliptical orbit, then make an additional TLI burn using the VDL’s on board engine. Another manoeuvre would then be needed once away from the Earth in order to help correct for the later departure time. Three days later, the VDL could perform the lunar orbit insertion manoeuver as planned and the existing flight plan could be resumed. The PROM itself has sufficient fuel on board to return to Earth from lunar orbit, and it was always planned to return from the Moon in this way.
The next opportunity to complete TLI is near the orbit's perigee, which will occur at T+8:26. Two hours of rapid recalculation and checking using the computer facilities at Biscarosse allow controllers to relay the parameters of the new burn up to the crew as their orbit carries them back down towards Earth. Flight medics are concerned that the additional time in high Earth orbit will expose the crew to additional radiation exposure in the Van Allen belts, however the predicted doses are still below overall crew and mission limits.
Having seen the Earth recede and approach in their elliptical orbit, the crew ignite the VDL's engine shortly before perigee. Thirteen minutes of thrusting uses up two-thirds of the VDL's fuel, but succeeds in putting them on a course towards the Moon.
Analysis of the ECPS failure begins immediately the VDL separates, just over 5 hours after liftoff. Booster controllers command a series of valve and actuator movements to try to gather more information on the fault before the stage's batteries run down.
Early press reports surrounding the "failure" of Selene 2 are very mixed, as it soon becomes apparent that the mission will still go to the Moon. Very negative reports in both Soviet and US press are clearly rushed and speculative. British and French media focuses on the efforts being made to resume the mission and praises both the crew's determination and the remarkable "real time computation" being carried out at mission control. TV news in Europe, and to a lesser degree elsewhere, gives continuous (if rather confused) updates on what is happening.
At T+30:06, a course correction is made using the VDL’s main engine, a manoeuvre that completes the process of realigning the trajectory to allow for the Moon being a few hours further along in its orbit than in the original flight plan. It is now possible to revert to something close to the original mission, albeit with a four hour delay added. At T+82hrs the crew make a colour TV transmission showing their ship and the crescent Moon, still 50,000km away from them.
The technical and managerial skills displayed by the drastic changes in the flight plan are not lost on several NASA observers. Many of their confidential reports back to the US state that this supposed "failure" actually shows that mission planning and operations within the Selene Project are of the highest quality, even if the bugs have not yet been worked out of the launchers and hardware. As one NASA flight controller later wrote “If we’d had a problem on the way to the Moon, I hope we would have done as well as these guys…”
The next day, at T+97:50, Harmony disappears behind the Moon, fifteen minutes before the lunar orbit insertion burn is due. When it is complete, only the crew will know if they are in lunar orbit or not. Mission controllers and the rest of the world must wait for the signal to reappear at the right time. Too soon, and the ship may not be in lunar orbit, too late and the ship might be heading for a collision with the surface.
When it appears at exactly the right time, T+98:21:06, Mission Control erupts in cheers and applause. The first Selene crew to orbit the Moon are in a 95x355km orbit, very close to plan. After two revolutions, they fire their engine again to circularise to the 115km orbit they will use for their lunar observation mission.
The first full day in lunar orbit is spent in testing the procedures that will be used for future landings, checking guidance solutions and setting up the systems. Larosse and Leyton-Arnold make the first ever spacewalk conducted outside of Earth orbit, out to Harmony’s external control cockpit. After a "night" in the VDL's Hab, the crew repeat the descent checkout procedures before photographing one of three possible prime landing sites.
Day 3 in orbit includes a third spacewalk to practice the attachment of refuelling lines using a new fitting, designed after the problems encountered on Aurora 11. No actual fuel transfer is planned, but the test of the new lines is a success. Photographs of a second potential landing site are taken later in the day.
The final day around the Moon sees more photographs of sites further west and two interviews, carried live on British and French TV. The PROM is separated from the VDL at T+212:15 and once again, the crew check their navigation systems before using the PROM’s engine to boost themselves onto a course back towards Earth.
A 1.4s correction at T+262:16 is all that is needed to target the ship for re-entry. RM separation is at T+301:38 and the crew feel the first effects of the atmosphere 12 minutes later, travelling at 11,008m/s (just over 24,600mph). They splash down within five miles of the recovery ship under two parachutes to complete a 12 day 14 hour mission.
What could have been a near-total failure was saved by the flexibility and training of the Selene Project’s crews and controllers. Despite the booster failure, the mission proves that the PROM/VDL-C flies as intended, and should be capable of attempting a landing later in the year.
