Satellite mystery solved

It took three satellites, and 8 years to solve it, but the mystery of the failures of Telstar 14, Telstar 14R, and Intelsat 19 has finally been solved. All three satellites suffered solar array failures during/after launch. It was initially thought they were unrelated, but the investigation proved they were related after all.

Space Systems/Loral revealed that the cause was an inadvertent solar array pressurization/decompression during launch that led to the failures. The initial failure was Telstar 14, when an explosive event was detected during the Zenit 3-SL (Sea Launch) flight. This led to the failure of the North solar array, and a lot of suspicion to fall on Sea Launch.

The second failure was Telstar 14R, on a Proton M Breeze M launch vehicle. The initial cause was put down to a clip snagging the array, but it was later determined that a similar explosive event caused the clip to snag the array.

The final failure led to the discovery of the problem, after Intelsat 19 had a difficult deployment of the array, and power loss. Investigators found another intra-fairing "pressure event".

The cause was found to be a manufacturing problem that led to the arrays becoming pressurized as the rockets climbed higher in altitude. This led to an explosive decompression, which led to a failure of the arrays.

I'm pretty sure I can hear Sea Launch cheering that the blame and suspicion have been lifted off them after all these years.

An obscure mechanism which caused three Space Systems/Loral-manufactured satellites, Telstar 14, Telstar 14R and Intelsat 19 to have solar array failures during their launches/deployments has finally been discovered. In an interview conducted in the space newspaper Space News (7 January 2013), John Celli, President of the US spacecraft manufacturer Space Systems/Loral, revealed that the eight-year-old mystery into why three satellites had major solar array failures had been solved by an independent investigation team. It found that it was inadvertent solar array pressurisation and exposive decompression that was the underlying cause.

Specifically, during the launch phase, the satellites' solar arrays had actually become pressurised relative to their ambient environment as the launch vehicle rose in altititude. This eventually led to an explosive event which damaged the array's deployment mechanism and structure. It was a manufacturing defect that was found to be the root cause including overly pinching the ends of the panels which would not let gasses vent from the honeycomb structure, and having insufficent bonding of the layers of the panel making it more susceptible to explosive depressurisation.

www.flightglobal.com...

Satellites are such complex things , and then the g-forces and vibration of launch not to mention the pressure changes , (not sure if that happens at deployment or earlier) I can see where one or two things can be overlooked .

What really amazes me is how everything can be done by the book (many books) with checklist after checklist of every single fiddle-winking thing thousands of some of the most intelligent people on earth can think of , and it still happens .

that's the same reason why they don't let astronauts eat taco bell before liftoff.

So in other words, the Solar arrays had...trapped wind.

Violently belched, and then died.

They had that happen to a few monkeys and dogs in the early days of the space race.

Oops.