Missile laboratory received FAA approval after its electron missile failed on July 4 and lost half a dozen satellites on board. "This was a very, very sneaky and tricky problem," said CEO Peter Beck. “However, the team understood the problem well. We are really looking forward to being on the pad again. "
The failure, Beck said in a press call, was nowhere near as catastrophic as many such incidents. While the payloads were lost during the uncontrolled descent of the vehicle, the missile did not suddenly explode or break, as sometimes happens, but appears to have quietly shut off during the second stage combustion due to "a single abnormal electrical connection".
"We were just on our way into orbit and were driving at a speed of around 4 km / s," Beck explained when a single part had a higher resistance than usual, which resulted in a heat build-up that led to safety systems breaking in and turned it off. “The shutdown was fully automated – of course we would do anything to try to put it into orbit and the vehicle has made an enormous amount of corrections to try to do so. But when you pull the plug, you pull the plug. "
This meant that, although the launch failed – threateningly the company's 13th – failed to send valuable information about what went wrong, which undoubtedly contributed to the quick resolution by the investigators.
"The mistake was very graceful, so we were able to get huge amounts of data," said Beck. "Literally 15 minutes after we saw the anomaly, the team started investigating it and they didn't stop."
Rocket Lab's own account of what happened is as follows:
On July 4, 2020, the Electron launch vehicle successfully launched from launch complex 1 and, as planned, underwent a nominal engine fire of the first stage, a stage 1-2 separation, a stage 2 ignition and a fairing release. A few minutes after the second stage was burned, the engine stopped safely, resulting in the orbit not being reached. Due to the controlled manner in which the engine was turned off, Rocket Lab continued to receive telemetry from the vehicle and provided the engineers with extensive data to conduct a thorough investigation of the problem. After reviewing more than 25,000 data channels and performing extensive tests, Rocket Lab's AIB was able to safely isolate the problem to a single abnormal electrical connection. This connection was temporarily secured during the flight, creating an increasing resistance which caused heating and thermal expansion in the electrical component. This caused the surrounding casting compounds to liquefy, which led to the interruption of the electrical system and the subsequent switching off of the engine. The problem could not be identified before the flight because the electrical connection remained secure during standard environmental impact assessments, including vibration, thermovacuum and thermal cycle tests.
Incidentally, for safety reasons and for other reasons, it is not advisable to have the vehicle try to “drive out” with a blown fuse. Precision is paramount. If the payloads are not delivered correctly, there is a risk of collision with another orbital object. And there is little appreciation for fulfilling a mission with the skin of your teeth – as a major start-up provider, Rocket Lab must show caution and professionalism, and scrubbing a mission when it is no longer nominal is the only true way to do it .
Beck said the part failure had escaped rigorous testing, but future testing would be even more rigorous.
"It was incredibly unusual. We have built over 720 of these components and this is the only one that has shown abnormal behavior, ”he said. "We can actually mitigate it very easily by slightly changing production processes, but more importantly, we can test it in existing vehicles in stock through more thorough testing."
He added that the team made a number of improvements during the month-long investigation process that were intended to further improve the vehicle without the need for major design or manufacturing changes.
"Electron deserved its stripes and we put 53 customers into orbit without errors," said Beck, but admitted, "this is the start-up industry, and these things happen." The reality is that anyone who now flies with Electron will fly with an even more reliable vehicle than before. "
After Rocket Lab has submitted its results to the FAA, it will now take on its next mission in August if there are no further delays. Although the start-up mistake meant a financial setback, Beck (though he didn't comment on insurance or customer reimbursement issues) seemed fairly calm.
"If you own a rocket company and want to launch vehicles, you have to be prepared for such things," he said, noting that the company "had a large chunk of capital in the bank for … bad things. It's not something we didn't plan. "
The plan to open the US-based Launch Complex 2 and to achieve a monthly starting rate this year has not yet been completed.