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'Creeping and Unpleasant': The Near-Space Experience of Soyuz 18A
By Ben Evans, on September 29th, 2013

In April 1975, cosmonauts Oleg Makarov (left) and Vasili Lazarev endured one of the most harrowing missions in the annals of human space exploration. Photo Credit: Joachim Becker /

Thirty years ago, Soviet cosmonauts Vladimir Titov and Gennadi Strekalov came within a whisker of death when their booster exploded on the Baikonur launch pad. Only the rapid extraction of the Soyuz T-10A spacecraft by the rocket’s escape system saved their lives, as discussed in yesterday’s AmericaSpace history article. Yet theirs was not the first brush with death experienced by cosmonauts in the secretive years of the Cold War. In April 1975—ironically, during a time of relative East-West transparency and friendship, coming just three months ahead of the Apollo-Soyuz joint mission—the crew of Soyuz 18A suffered their own launch mishap. Today innocuously described as “The 5 April Anomaly,” it remains one of the world’s most harrowing near-death (and near-space) experiences.

Cosmonauts Vasili Lazarev and Oleg Makarov were destined for a two-month expedition to the Salyut 4 space station when they blasted off from Baikonur in today’s Kazakhstan—then a satellite state of Soviet Central Asia—on 5 April 1975. Their ascent toward orbit proceeded without incident, until they reached an altitude of about 90 miles, when things began to unravel with horrifying rapidness. Ordinarily, two sets of pyrotechnics should have fired to separate the core of the booster from its upper stage and six latches should have blown. It did not happen. “An excessive degree of vibration caused the relay in half of the upper sequencer to close down and to signal three of the six latches to fire prematurely,” explained Rex Hall and Dave Shayler in their book Soyuz: A Universal Spacecraft, “with the lower core and upper stages still firmly attached. This was activated only seconds prior to the planned separation, but with the latches armed. The connection that triggered was in the same location as the electrical link between the upper and lower segments of the structure. Therefore, when the electrical contacts were severed due to the premature explosions, so [too] were all links to the lower latches, causing an uneven linkage between the core and upper stage as the vehicle continued to climb.”

Cosmonauts Vasili Lazarev (left) and Oleg Makarov flew together on Soyuz 12 in September 1973, which was the first flight since the Soyuz 11 re-entry disaster. On their second flight together, they came face-to-face with the dangers of launch and the implications of a launch vehicle failure. Photo Credit: Joachim Becker /

The upper stage ignited on time … but the central core was still attached. Although the thrust of the upper stage engine broke the remaining locks and separated the stages, within seconds the unanticipated strain threw the booster off its intended trajectory. The on-board gyroscopes detected a deviation beyond the mandated safety limit and automatically commanded an abort. Two hundred and ninety-five seconds into Lazarev and Makarov’s mission, the escape tower fired to pull the Soyuz orbital and descent modules away from the booster.

All at once, the Sun disappeared from sight and a loud siren sounded. On the instrument panel, the red “Booster Failure” light illuminated. For a few moments, the cosmonauts wondered what was happening as the sound of the rocket ceased and they became temporarily weightless as their forward velocity faltered. Now on the fringes of space, Lazarev and Makarov could only grit their teeth as the abort system automatically released the bell-shaped descent module to plunge back to Earth. Normally, they could have expected an acceleration of 15 G in such an emergency, but since Soyuz 18 was already pointing directly downward, its rate increased and the two men were subjected to a punishing 21.3 G of deceleration. “We began to experience a creeping and unpleasant pull of gravity,” Lazarev recounted later. “It increased rapidly and its rate was much greater than I had expected … Some invisible force pressed me into my seat and filled my eyelids with lead … Breathing was becoming increasingly more difficult … ” The two men could barely communicate with one another, scarcely able to utter more than a few grunts, wheezes, and puffs under the immense loads.

The descent module’s parachutes deployed as intended and Soyuz 18 came down in the snow-covered Altai Mountains, about 510 miles north of the Chinese border. It landed on a slope and began to roll toward a sheer precipice. Thankfully, the parachute snagged on some vegetation. In temperatures of -7° C, the cosmonauts donned their cold-weather clothing and clambered outside. Having radioed a request for tracking information during the descent, but met with silence on the airwaves, Lazarev was afraid that they had landed in China, and one story relates that he burned a pile of classified papers for a military experiment which he would have performed aboard Salyut 4.

In fact, their flight path passed to the northwest of Xinjiang, which had entered the headlines in March 1974 when a Soviet helicopter landed there in error and its pilots were captured by a Chinese military patrol. At length, Lazarev and Makarov encountered friendly locals who spoke Russian, and a helicopter rescue team quickly made radio contact.

The landing of the latest Soyuz crew on 11 September 2013 shows that despite launch accidents such as Soyuz 18A and Soyuz T-10A, the spacecraft and its launcher remain one of the most reliable in the world. Photo Credit: NASA

“Oleg calculated the landing place almost precisely,” Lazarev said later of the flight engineer’s navigational prowess during the descent. “We landed a bit to the side of the place he had indicated. It was painfully disappointing and somewhat unpleasant. We had prepared ourselves for the mission for so long, only to wind up like this … The very fact of failure was quite discouraging.” They had touched down close to the town of Aleysk, about 125 miles south of Novosibirsk, in southern Siberia—well within Soviet territory.

However, it was the next day, 6 April, before a rescue team, battling the terrain, the chest-deep snow drifts, and the high altitude, was able to reach them. Plans to drop a team of doctors onto the mountain were called off by Lazarev—a veteran parachutist himself—after deciding that it was too dangerous. Next morning, it was hoped to extend a ladder from a helicopter, but the instability of this option made it impractical; another effort led to a group of would-be rescuers getting stuck in an avalanche. Finally, a civilian helicopter dropped a forest guide next to the two cosmonauts to render assistance, and a military helicopter arrived and extracted all three of them.

The Soviet news agency Tass revealed the shocking truth when it announced that the booster had “deviated from the pre-set values” and “an automatic device produced the command to discontinue the flight.” Veteran cosmonaut Vladimir Shatalov, then chief of the cosmonaut corps, made a statement asserting that Lazarev and Makarov were in good shape and ready to fly again. This was far from accurate. “Makarov says that under the G forces which they experienced, they could easily have first lost vision and then consciousness,” wrote Hall and Shayler. “Although this did not happen, they experienced black-and-white vision and then tunnel vision.” Makarov did make a full recovery and flew two more missions, but Lazarev suffered undisclosed internal injuries and never flew again. In the days after the flight, a rumor circulated that the two cosmonauts had died in the accident. This was quickly suppressed when they were ordered to play football with some Americans, simply to prove that they were still alive. …

The flight—which became known as “Soyuz 18A,” as another Soyuz 18 mission successfully boosted cosmonauts Pyotr Klimuk and Vitali Sevastyanov toward Salyut 4 in mid-May 1975—was effectively suborbital, reaching an apogee of 74 miles and lasting 21 minutes. With the joint Apollo-Soyuz mission looming in July, many U.S. senators vocalized their criticism of the Soviets’ safety record. It was declared that Lazarev and Makarov had flown an older version of the Soyuz booster, which would not be used on the joint flight, but Senator William Proxmire of Wisconsin remained skeptical. NASA Administrator James Fletcher wrote to Proxmire, stressing that the fault lay with the booster and not the Soyuz. “The mission plan calls for a U.S. Apollo launch only after a fully satisfactory Soviet Soyuz launch,” Fletcher explained. “Therefore, the U.S. safety concerns focus on spacecraft, rather than launch vehicle questions.”

Since April 1967, Soyuz and its launch vehicle have delivered dozens of crews from various nations—including the United States—perfectly into orbit. Photo Credit: Bill Ingalls / NASA

For Proxmire, this explanation missed the point. Whether a rocket failure or a spacecraft failure, the reality was inescapable. The Soviets had now launched 17 manned Soyuz spacecraft, of which two had ended in disaster—Vladimir Komarov’s ill-fated Soyuz 1 flight in April 1967 and the tragic re-entry of Soyuz 11 in June 1971—and now Lazarev and Makarov had cheated death by a hair’s breadth. Of the other 14 flights, two others had experienced docking problems and could hardly be considered successes. Effectively, Proxmire concluded, that meant five manned missions (more than a quarter of the total) had either totally failed to achieve their objectives or had ended with a loss of human life. By early July 1975, only two weeks before the Apollo-Soyuz joint launches, he made public the testimony of the CIA’s deputy director of science and technology, Carl Duckett, who had raised questions in June about the ability of the Soviets to control two manned missions simultaneously. At the time, the Soyuz 18B crew was aboard Salyut 4 and their two-month mission was expected to overlap Apollo-Soyuz.

“This warning from the nation’s top scientific intelligence expert,” Proxmire said, “should not be taken lightly.” In his testimony, Duckett expressed concern that Soviet communications capabilities and central management facilities were inferior to those of the United States and operating two missions in tandem offered a disturbing indication that Apollo-Soyuz might not receive the full support for success. Proxmire urged NASA to postpone the launch until after the Salyut crew had returned to Earth. Responding to Proxmire’s letter on 3 July 1975, Fletcher noted that the Soviets would employ two control centres—one at Yevpatoria in the Crimea for the Salyut flight and a newer complex in Kaliningrad, just outside Moscow, for Apollo-Soyuz.

The senator remained unconvinced. On 11 July, a few days before launch, he entered anti-ASTP articles in the Congressional Record, and on the 14th cited CIA data which seemed to indicate that the Soviets had encountered “severe problems” in space and that their technology was fundamentally inferior to that of the United States. Specifically, he cited the fallibility of their docking apparatus, their general lack of preparedness for the ASTP mission, the poor standard of training facilities, and a history of failings in both their Soyuz and lunar programs.

As circumstances transpired, Apollo-Soyuz flew perfectly, as did the Soyuz 18B mission and its expedition to Salyut 4. However, the calamity which engulfed Vasili Lazarev and Oleg Makarov that April day in 1975 would underline the sheer gutsiness which has always been demanded of spacefarers. It demonstrated the resilience of the Soviets in their ability to rebound from failures, and, today, in 2013, the descendents of Soyuz 18A remain operational and have secured their place as one of the most reliable and long-lived launch vehicles and crew-carrying spacecraft the world has ever known.