The Nedelin catastrophe or Nedelin disaster was a launch pad accident that occurred on October 24, 1960, at Baikonur Cosmodrome during the development of the Soviet R-16 ICBM. As a prototype of the missile was being prepared for a test flight, it spontaneously exploded on the launch pad, killing over 100 military personnel, engineers, and technicians working on the project. Despite the magnitude of the disaster, it was covered up for many years by the Soviet government and did not emerge until the 1990s.

Prequel to Disaster

Designed by experienced rocket scientist Mikhail Yangel , the R-16 develepment program was commanded by Strategic Rocket Forces Marshal Mitrofan Nedelin . In October of 1960, the rocket was nearing completion, and Yangel and Nedelin hoped to produce a successful launch before the November 7 anniversary of the Bolshevik Revolution. A prototype of the rocket was ready on the launchpad at Site-41 at Baikonur Cosmodrome, and the numerous tests that had to be undertaken before launch were commenced without delay. Despite their extensive experience with the R-12 and R-14 missile programs, neither Nedelin nor Yangel recognized the danger associated with rapidly preparing a prototype rocket.

October 23

On October 23, the prototype R-16 was ready on the launch pad and was only awaiting a few final tests before launch. The rocket had already been fuelled with its hypergolic UDMH-nitric acid fuels. These chemicals are extremely toxic, and, when burned, produce toxic gas; but they were used for their reliable characteristics in rocketry. As well, the nitric acid component was extremely corrosive. All of these risks were accounted for in the safety procedures for preparing the rocket, but late that day the pyrotechnic membranes on the first stage fuel lines were accidentally blown up, allowing fuel to move to the combustion chamber. While this did not cause immediate danger, the nitric acid fuel component was so corrosive that it could not remain in the fuel lines for more than two days without irreparably damaging the rocket. Thus, the rocket team had to either launch the R-16 the next day, or completely drain the rocket and rebuild the engine - delaying the program by several weeks. The decision was made to launch the next day, and preparations for launch were ramped up to a breakneck pace. Nedelin also notified military dignataries of the launch so that they could come and observe it. Several other components of the rocket were tested that day and replaced or adjusted as per the usual launch procedures.

October 24

On October 24, preparations continued. So many procedures were left to carry out that many had to be performed simultaneously. As the day wore on, Nedelin grew impatient with the delays and left the viewing area where the military dignitaries were seated a safe distance away. Nedelin returned to the launch pad to personally oversee the preparations, setting up a chair right beside the rocket.

During the course of the pre-launch operations, a Programmable Current Distributor, or PCD, was left switched to the post-launch position. It was supposed to be returned to the pre-launch position from whence it would issue series of timed electrical commands to the rocket during launch to blow up the appropriate pyrotechnic membranes to coordinate the engines and stage separation. Later, an engineer noticed that the PCD had not been returned to zero and switched it back. However, the rocket’s onboard batteries had been powered up and connected since the PCD test. Thus, upon moving the PCD back along its path, the first setting the PCD encountered blew the pyrotechnic valves to fire the second stage of the rocket engine.

The second stage engines fired immediately, the flames cutting into the fuel tanks of the first stage immediately below them. A massive explosion and fires resulted. Those near the rocket were instantly incinerated, while those further away burned to death or were killed by the resulting toxic gases. Nedelin and over 100 others were killed, but ironically, Yangel survived. He had left the area for a smoking break where he was discussing the possibility of abandoning the launch with the chief technicians.

Aftermath

Complete secrecy was immediately imposed on the events of October 24th by Nikita Khrushchev. A news release stated that Nedelin had died in a plane crash, and the families of the other engineers were advised their loved ones had died of the same cause. Khrushchev also ordered Leonid Brezhnev to assemble a commission and head to the launch site to investigate. Among other things, the commission found that many more people were present on the launch pad than should have been — most were supposed to be safely offsite in bunkers.

After the committee presented their report, the R-16 rocket program was resumed in January 1961 with its first successful flight that November.

References

• Khrushchev Sergei. Nikita Khrushchev and the Creation of a Superpower. Pennsylvania State University Press, Pennsylvania, 2000. Translated by Shirley Benson. pp 416-425.
• Harford, James. Korolev – How One Man Masterminded the Soviet Drive to Beat America to the Moon. John Wiley & Sons, Inc., New York, 1997. pp 119-120.

External Links

• Nedelin Disaster on RussianSpaceWeb.com
• Video Cosmos