The mission

Skif-DM’s FSB section was delivered to Baykonur in May 1986, followed by the Payload Module in July 1986. Amazingly, the latter had been built virtually from scratch in less than a year’s time. Final assembly of the spacecraft took place in the Proton area of the cosmodrome. The originally planned launch date of September 1986 turned out to be overly optimistic and initially slipped to 15 February 1987 and later to April. In late January 1987 both Energiya 6SF and Polyus were transferred to the MZK, where they were mated on 3 February. Roll-out to the UKSS, which had been quickly modified to serve as a launch pad, took place on 11 February 1987.

Meanwhile, the political tides in Moscow had been turning against Skif-DM’s intended mission, which did not fit in with Mikhail Gorbachov’s propaganda campaign against America’s SDI program. During a US-Soviet summit in Reykjavik in October 1986, Gorbachov and Reagan had come close to striking a radical arms reduction deal, but the talks had finally stalled over Reagan’s refusal to abandon SDI. Despite all the carefully concocted cover-up stories for Skif-DM, the Russians were probably well aware that it wouldn’t take Western analysts long to figure out what the spacecraft’s real mission was. Clearly under political pressure, the State Commission in charge of the flight decided in February to cancel all the “battle station’’ related experiments—namely, deployment of the targets, tests of the laser-pointing mechanism, and release of the xenon and krypton gas. Save for the technological and geophysical experiments, Skif-DM would now essentially fly a passive one-month mission before deorbiting itself above the Pacific. One wonders if this type of mission wouldn’t have spawned even more rumors than it was supposed to avoid.

The Energiya-Skif-DM stack (also known as 14A02) spent more than three months on the pad, braving temperatures between —27° and +30°C. Finally, by early May all the tests and preparations had been completed. Actually, the launch could have taken place earlier, were it not for the fact that it was timed to coincide with a visit to Baykonur by Gorbachov in mid-May. Cosmodrome workers were not informed of the impending visit, but became suspicious when they were asked to repeat the same checks over and over again. There is conflicting information as to whether Gorbachov was supposed to watch the launch or not. One version has it that he was offered the opportunity to witness the launch, but declined. Other sources say

Skif-DM/Polyus on the UKSS (source: www. buran. ru).

Gorbachov touring Baykonur facilities in May 1987 (source: www. buran. ru).

the State Commission in charge of the mission decided not to push its luck and delayed the launch from 12 May to 15 May, by which time Gorbachov would have returned to Moscow. Officially, Gorbachov would be told the launch had been postponed for technical reasons.

Gorbachov arrived at the space center’s Yubileynyy runway on 11 May and watched the launch of a Proton rocket with a Gorizont communications satellite later that day. On 12 May he was treated to a tour of the Energiya-Buran facilities. After inspecting the Energiya-Polyus poised for launch on the UKSS, Gorbachov was taken to one of the Energiya-Buran pads, where an Energiya rocket with the OK-MT Buran model strapped to its side had been erected for a series of tests. He also visited the Energiya and Buran assembly buildings.

As Boris Gubanov recalls in his memoirs, Gorbachov made several remarks during the tour that raised serious doubts about his support for the program and left a bitter aftertaste among the space officials accompanying him. He openly questioned whether Buran would have any future applications and on several occasions voiced his opposition to the militarization of space, of which Buran was supposed to be part and parcel. He even expressed skepticism about the readiness of Energiya, although later that day he informed the launch team that the Politburo had given its official approval for the launch. He also approved Glushko’s suggestion to officially call the rocket Energiya. Up till then the rocket had received no individual name, with “Buran” being used to refer to the combination of the rocket and the orbiter and “Buran-T” for the combination of the rocket and an unmanned payload canister. On 13 May, Gorbachov was on his way back to Moscow, after having watched the launch of a Zenit rocket with a Tselina-2 electronic intelligence satellite.

In another demonstration of glasnost, the TASS news agency issued a statement on Gorbachov’s visit later that day, saying:

“Right now preparations are underway at the cosmodrome to launch a new universal rocket carrier, capable of placing into near-Earth orbits both reusable orbital ships and large-size spacecraft for scientific and economic purposes, including modules for long-term space stations.’’

This was the first confirmation by TASS of the existence of a new heavy-lift launch system and a Soviet shuttle vehicle. However, there were still limits to openness when it came to the launch of an untried launch vehicle. While Soviet television and radio had begun carrying live coverage of manned Soyuz launches in March 1986, the exact launch date for Energiya was kept secret and TV images of the launch would not be released until after it had taken place.

The launch of Energiya was targeted for 15 May at 15:00 Moscow winter time (12: 00 gmt). Fueling of the rocket got underway at 8: 30 with the loading of liquid oxygen in the core stage and strap-on boosters. However, problems with the gaseous helium supply to one of the strap-on boosters and also a stuck valve in the core stage’s liquid hydrogen tank pushed back the launch 5.5 hours. By that time the sun had set at Baykonur, but, since the payload did not impose any launch window constraints, the launch team decided to press ahead. At T — 10 minutes the countdown entered the so-called “pre-launch phase’’, with all operations being controlled automatically. Any hold during this final part of the countdown would automatically lead to a scrub. A major malfunction did occur with less than a minute to go in the countdown, when the sound suppression water system could not be activated. Although this would lead to higher than usual thermal and acoustic loads on the vehicle and the pad, tests conducted at NIIkhimmash had shown that Energiya could safely lift off without the sound suppression water. Therefore, computers had been programmed not to stop the countdown in the unlikely event such a failure took place.

With about 9 seconds left in the countdown, Energiya’s four RD-0120 engines roared to life. As the huge cryogenic engines built up thrust, the four RD-170 engines of the strap-on rockets were ignited at T — 3 seconds and, with all engines having reached full thrust, Energiya 6SL leapt off the pad at 21: 30 Moscow time (17: 30 gmt), lighting up the night sky at Baykonur. Just moments later onlookers saw to their consternation how the rocket significantly leaned over in the direction of Polyus, only to stabilize itself as it cleared the tower. Energiya’s automatic stabiliza­tion system had been programmed to remain inactive until T + 3 seconds to ensure that it would not command the engine nozzles to gimbal as they emerged from the Blok-Ya launch table adapter. Therefore, the deviation from the trajectory had been more or less expected, but not everyone watching the launch was aware of this and for a few hair-raising moments it seemed as if Energiya would befall the same fate as its

illustrious predecessor, the N-1. For the next launch the stabilization system was programmed to kick in earlier to prevent a repeat of this scenario.

Having cleared the tower, Energiya initiated a roll and pitch maneuver to place itself on the proper azimuth for a 64.6° inclination orbit. There had been some debate in the months prior to launch whether to put Polyus into a 50.7° or 64.6° orbit. A launch resulting in the lower inclination would have allowed Energiya to be about 5 tons heavier, but at the same time would briefly carry the rocket over the territories of Mongolia, China, and Japan. An argument against a 64.6° inclination orbit was that launches were not possible between mid-May and August because the strap-on boosters and Polyus’ payload shroud would impact in the nesting grounds of the pink flamingo, a protected species that has its breeding season during that time of the year. In the end, concerns about Energiya debris raining down on foreign territory seem to have outweighed any environmental arguments.

Managers breathed a sigh of relief at T + 30 seconds, by which time Energiya 6SL had moved far enough downrange to prevent damage to the UKSS in case of an explosion. Also, the objectives of the originally planned combined static test firing of the core stage and strap-on boosters had now been achieved. Any success beyond that was a bonus as far as managers were concerned. To their delight, Energiya continued to perform outstandingly. The four strap-ons were separated from the core stage at T + 2m26s, and at T + 3m34s Polyus shed the shroud that had protected its upper FSB section against the aerodynamic pressures experienced during the early stages of launch. At T + 7m39s the RD-0120 engines shut down, followed moments later by the separation of Polyus from the core stage, which according to unconfirmed reports came down relatively intact in the Pacific Ocean [12]. The Energiya control room at Baykonur erupted into applause, but while Energiya had completed its job, Polyus still had some critical maneuvers to do.

Not having reached orbital velocity yet, Polyus now was to perform two burns of its FSB main engines to place itself into a circular 280 km orbit. With the FSB section placed on top (as during a TKS launch on Proton), Polyus first had to carry out a 180° flip maneuver around its z-axis so that the engines would face aft for the burns, followed by a 90° roll around its v-axis. Unfortunately, due to a programming error, the FSB’s thrusters failed to stop the flip maneuver and by the time the main engines were ignited Polyus was not oriented properly and as a result deorbited itself. Later analysis showed that the thrusters had been deactivated by a command usually issued during a TKS launch that somehow had not been erased for the Polyus launch.

The official TASS launch statement released the following day acknowledged the failure to place the payload into orbit:

“The second stage of the rocket delivered a satellite mock-up to the required point, but due to a malfunction of its on-board systems the mock-up did not go into the planned orbit and splashed down in the Pacific.’’

The day after the launch Soviet television viewers were treated to spectacular shots of the super-booster on its launch pad. One of the television shots offered a side view of the payload, revealing it to be a black pencil-shaped object. However, photographs

released subsequently only showed the aft part of Energiya, hiding Polyus from view. It was not until many years later that detailed photographs and descriptions of the payload became available.

The loss of Polyus was a bitter pill to swallow, especially for the designers and engineers of KB Salyut and Khrunichev, who had managed to get the improvised payload ready for launch in such a short period of time. Another setback was the significant damage to the UKSS launch pad, caused by the problem with the sound suppression water system and the rocket’s deviation from its trajectory shortly after lift-off. The Blok-Ya launch table adapter, designed to support at least 10 launches, was rendered useless because thermal protection covers had been either torn loose or closed too late.

Still, the primary goal of the launch had been to test Energiya and demonstrate its capability to carry a heavy payload and both these objectives had been accom­plished. Particularly useful for the subsequent Buran mission was the use of the same systems needed to separate the vehicle from the core stage. Moreover, all the four technological experiments and even some of the geophysical experiments planned for launch and the post-separation phase were actually carried out successfully. Energiya had performed better than anyone could have hoped and was declared ready to carry Buran on its next mission [13].