Good morning everyone. At the end of Part-II we left Neil Armstrong piloting the first orbital Dynasoar mission into orbit. Let's see how he got on, in...
Part III Post #2: Proof of Concept
10th November 1966 saw US Air Force astronaut Neil Armstrong circling the Earth aboard the spaceplane
Aura on mission DS-6. Coming over two years after Armstrong’s last space flight as part of the joint Mercury-6/7 mission, the Dynasoar spacecraft represented a quantum leap in capabilities over the old capsules. Soon after reaching orbit, Armstrong began testing those capabilities by using the RCS thrusters of the Dynasoar glider and Mission Module to turn the ship in all axes. The ship displayed crisp control, which Armstrong reported as being far more responsive than Mercury. He next demonstrated Dynasoar’s ability to modify its orbit, using the Mission Module engines to raise his apogee by 60 km and shift inclination by just over 2 degrees. This ability was something beyond Mercury’s capabilities, and proved that the USAF could now match, and perhaps exceed, the on-orbit manoeuvrability of the Soviet Zarya and Orel spacecraft.
With the basic capabilities of the Dynasoar spacecraft to manoeuvre and support its pilot demonstrated, day two of the mission saw Armstrong work to validate the system’s ability to perform a militarily useful function when he opened the doors of
Aura’s small payload bay, exposing her top-secret cargo to space for the first time. On this first test flight,
Aura carried a relatively simple visible and infra-red imaging system provided by the NRO, code-named EPOCH, which Armstrong was able to control through a workstation at the rear of his cockpit. Over the course of three orbits, Armstrong used EPOCH to image locations in North America from both directly overhead and at slant angles, allowing analysts on the ground to assess the images post-flight against targets with known characteristics. The payload bay also contained three smaller payloads (two Air Force, one NRO) containing components and materials being considered for use on future satellites which Dynasoar would test for the effects of exposure to space. This phase of the mission was kept top-secret, and Air Force press releases simply noted that Armstrong was engaged in unspecified “Tests of the craft and its equipment”.
After three days aloft - almost ten times longer than the previous US space endurance record - Armstrong fired the Mission Module’s engines one last time and put the glider on a trajectory that would re-enter Earth’s atmosphere over the US Pacific coast. The Mission Module was discarded to burn up in the atmosphere, whilst the
Aura glider was re-orientated to enter the atmosphere belly-first. Unlike on the suborbital test flight to Fortaleza earlier that year, this time the water wall cooling system worked flawlessly, maintaining a comfortable temperature inside the cabin as the ship plunged through the upper atmosphere. As the plasma sheath dissipated, Armstrong jettisoned the cockpit window heat shield and piloted
Aura through a series of energy-dumping S-turns, before finally guiding her in for a triumphant landing at White Sands.
In February 1967,
Aura was followed into orbit by her sister Mk.I glider,
Rhene. Piloted by Mercury-4 veteran Bob White, the DS-7 mission marked the first launch of a Dynasoar from Vandenberg Air Force Base. Launching into a 250 x 500 km polar orbit,
Rhene carried in her payload bay a large deployable antenna designed to monitor Soviet air defence radars as she passed over northern Russia. As with Armstrong’s earlier mission, White’s electronic intelligence duties were kept secret from the public, although the Air Force did release a blurry video transmission of White inside his spacecraft to TV news outlets, after it had been screened for images of sensitive instrumentation. Most networks featured a ten-second clip of the video on the evening’s news bulletins, usually as the second or third-run story, but beyond that it failed to make much of an impact.
Perhaps the most significant experiment of DS-7 was a first attempt to perform a “synergistic plane change”. On day four of the mission, White fired the manoeuvring engines of his Mission Module to lower
Rhene’s perigee to just 80 km. As it entered the upper atmosphere, White used
Rhene’s aerodynamic surfaces to pull her through a 0.2 degree plane change, before skipping back into space and raising his perigee again with a propulsive manoeuvre. The manoeuvre worked, but confirmed that for such minor corrections the propellant expended to compensate for the loss of orbital altitude due to drag was actually higher than if the entire manoeuvre had been made on rocket power alone.
Rhene finally returned to Earth on day five of her mission, close to the limit for the fuel cells carried in her Mission Module. When making his final approach, the heat shield protecting the cockpit windows refused to jettison, and White was forced to make an instrument landing at White Sands with his visibility restricted to just the two side windows. This was a contingency that all of the Dynasoar pilots had trained for, and White brought his ship down to a successful landing despite his impaired view.
After their first Orel mission in July 1966, the Soviets had failed to follow up with more Raketoplan missions. Though Shelepin was pleased to be able to point to Orel as having beaten the Americans to fielding the world’s first spaceplane, he did not have Khrushchev’s drive to seek publicity for its own sake. Shelepin’s main concern at this time was consolidating his grip on power, ensuring that the “Collective Leadership” established after Khrushchev’s ouster would be firmly “collected” under the Party he now chaired. His main rival for power was his erstwhile ally, now Chair of the Council of Ministers, Leonid Brezhnev, and Shelepin quickly moved to sideline his former comrade and ensure the support of the bulk of the Politburo. In particular, Shelepin made sure to get the Red Army on-side, and to that end began a large ramp-up in military spending. Both Shelepin and the new Chairman of the Supreme Council of the National Economy, Dimitry Ustinov, felt that the cuts to conventional forces under Khrushchev had been a grave error, and they immediately set about reversing this trend. Khrushchev’s regional economic councils were summarily disbanded and resources that had gone into expanding the civilian economy were diverted back into tank and jet production. Tentative talks with the US on limiting the deployment of nuclear weapons were cut off and a new programme of expansion of the Rocket Forces was begun. Anyone who raised a voice against this course of action was liable to receive a visit from one of Vladimir Semichastny’s KGB officers.
For the Soviet space industry this surge in defence spending was for the most part a considerable boon. Yangel in particular found his resources expanding as he was charged with doubling the production of long- and medium-range combat missiles. Funding for Mishin’s military communications and spy satellites was also increased, and the development of his military space station programme (now re-named “Chasovoy”, or “Sentry”, since its reallocation from Chelomei) was accelerated.
In contrast, Chelomei’s OKB-1 was left short-changed. Ustinov had not forgotten the Chief Designer’s earlier arrogance, and funding for further Orel flights was curtailed, limited to a single mission in May 1967. This flight, piloted by Yury Artyukhin, used the same Orel spaceplane as Shatalov’s 1966 mission. This allowed Chelomei to claim another ‘first’ in re-usable spacecraft technology, but as a military mission it provided even less operational value than the first flight when the antennas of the primary ELINT payload became stuck and refused to deploy. Consideration was given to ordering Artyukhin to make a spacewalk to unstick the antennas - after all, what was the point of flying a manned spacecraft if not to take advantage of the adaptability of a human being? - but in the end it was decided that this would be too big a risk. Artyukhin had no co-pilot who could help him should he run into difficulties. Artyukhin was able to duplicate on a smaller scale DS-7’s synergistic plane change manoeuvre, shifting his orbit by a tenth of a degree through aerodynamic forces, but Soviet engineers quickly reached the same conclusion as their American counterparts that such manoeuvres were of limited value. With his jammed antennas leaving him unable to fulfill his primary mission of monitoring US Navy radars in the eastern Mediterranean, Artyukhin was ordered to return to Earth after two and a half days aloft. To add insult to injury, the Orel’s jet engine again failed to start in mid-air, leaving Artyukhin to glide the plane down to an unpowered landing. Whilst the Soviet media reported the mission as another triumph for Socialism, amongst the military leadership the old joke “Chelomei builds crap” was becoming less and less funny.
Chelomei’s suffering only became worse in June, when Mishin launched the twin spacecraft of Kosmos-52 and Zarya-8. A re-try of the on-orbit rendezvous mission previously attempted with Zarya-6 and Kosmos-45, this time cosmonaut Aleksei Leonov was able to pilot his ship to a successful docking with the unmanned target vehicle after a three-day orbital chase. Leonov then used Kosmos-52’s engines to raise the orbit of the joined spacecraft by fifteen kilometres. This achievement was not only a minor propaganda coup for Mishin and the USSR, but it also proved the techniques and equipment that would be needed in support of the Chasovoy space station. When Leonov returned to Earth at the end of his five-day mission, he was met at the landing site by Mishin himself, who embraced the cosmonaut and gave him a slug of vodka from a hip flask in celebration.
In the US, the managers of the Dynasoar project had hoped by this stage to have been able to demonstrate the re-use of one of their Mk.I gliders. Unfortunately, upon their return to Earth
Aura and
Rhene were both found to have suffered more severe stress from re-entry than had been anticipated. In particular, some sections of the Rene-41 skin on the upper surfaces of both gliders were found to have warped slightly. Although the distortion was not enough to have caused any problems on their first missions, there was concern that repeated re-entries could result in a break in the hull, and so it was decided that the affected areas would have to be replaced between flights. In addition, detailed inspections of the entire spacecraft were carried out to ensure no other unexpected damage had occurred. All this led to a delay in the return to flight of either of the two Mk.I gliders, and so it was the Mk.II ship
Athena that was the next Dynasoar on the pad.
Launching from Cape Canaveral on a Minerva-22, mission DS-8 was the first multi-man launch for the US, with pilot Pete Knight joined by Paul McEnnis and Edward Karski. To support the enlarged crew, the DS-8 Mission Module carried almost a tonne more consumables than on either of the Mk. I missions, as well as 200 kg of externally mounted experiments for exposure to the rigours of space.
Despite the careful preparations and the experience built up on the previous two launches, mission DS-8 almost ended before it had fully began. Following a successful lift-off and LRB separation on 2nd October 1967, the guidance system of the Minerva core stage began to drift from the planned trajectory. After an attempt by Mission Control to correct the problem failed, Knight took manual control of the booster and steered it back to the proper course. Less than a minute later staging occurred as planned, and the hydrogen-oxygen upper stage performed perfectly with no further input needed from Knight. The final orbit was just over two kilometres short of the mission plan, an impressive achievement for the world’s first manually piloted orbital launch. It was not to be the last such achievement of the mission.
After four days aloft, the crew of DS-8 had demonstrated the ability to successfully live and work in the cramped conditions of
Athena’s cabin. Now it was time to demonstrate their ability to leave that cabin. After all three astronauts had donned their spacesuits, the cabin pressure was allowed to slowly bleed into space until the interior of the ship was reduced to a vacuum. Paul McEnnis then opened the hatch above the pilot’s position and, with his two crewmates watching, pulled first his torso, then his whole body out into space. Still attached to
Athena via twin tethers, McEnnis drifted against the backdrop of Earth as Knight took photos of America’s first spacewalker. After pausing for this photo-op, McEnnis quickly moved on to the primary objective of his space walk (or “Extra-Vehicular Excursion”, EVE, in the jargon adopted by the Air Force). From their position inside the glider, Knight and Karski passed a jointed, telescoping pole through the hatch, attaching it to a fixture on the rim of the hatchway. McEnnis pulled himself back to the hatch using his tethers, then proceeded to extend the pole (or “Mobility Assist Device”, an acronym originally suggested in jest by the astronauts themselves) along the outside of
Athena, attaching extra segments from inside the cabin until the entire structure was almost nine metres in length. McEnnis then used “this Mad Pole” to pull himself along the ship to the Mission Module, with the aim of retrieving one of the externally mounted experiments for return to Earth. Unfortunately, the pressure inside his suit gloves hampered McEnnis’ dexterity to a far greater degree than anticipated, and after five minutes of struggling with the simple (on Earth) fixture mechanism, Mission Control decided to cancel the attempt. His exertions were causing McEnnis to burn through his oxygen supply at a faster rate than anticipated, so the call was made for him to return to the cockpit immediately. Frustrated, McEnnis obeyed, and five minutes later the three astronauts were re-united at the hatch. After a minor scare when it appeared the MAD might be jammed in place, blocking the hatch from closing, Knight was able to force the pole free and push it into space, before closing the hatch and repressurising the cabin. The next morning, the triumphant trio returned to White Sands as heroes.
Paul McEnnis becomes the first American to walk in space, 6th October 1967.
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Special thanks to
Shevek23 for his excellent analysis of the synergistic plane change.