Rocket Lab CEO reflects on company's humble beginnings as a drainpipe Rocket Lab CEO Peter Beck spoke at the SmallSat 2022 conference and offered up words of wisdom for anyone pondering an entry into the lighter end of the launch market. After apologizing for his virtual presence – Beck had sensed an imminent propulsive emission of his own before boarding and wisely swapped a 20-hour flight for …
There aren't enough small satellites for the currently operational small rockets. The more alert small rocket companies are now talking about medium sized rockets. Perhaps a couple of them will reach orbit before the rest realise they have to talk about large rockets...
Running engines over 100% is common in rocketry. The early designs and prototype engines set the 100% mark, so it's quite common for later revisions to be better. The power outputs are still referenced to the original designs, meaning 110% isn't unusual.
The shuttle used to regularly throttle the engines to 107%.
Engine output is also calculated at a specific altitude at optimal fuel/oxidizer ratio and the turbo pumps running at designed optimal head pressure and flow. By increasing the rocket chamber pressure and thus making the pumps run at slightly above optimal settings engine efficiency (specific impulse) is slightly increased lower in the atmosphere. IIRC the space shuttle engines were designed to run at 500.000 lbs of thrust, but design optimization resulted in them running at aprox. 540.000 lbs (108%) and they could actually throttle to 115% (Which they would only do if the shuttle lost the center engine in the later stages of launch for a once around abort or abort to orbit).
However, in sport (just like in design), you should revise your design output at the point where you regularly (and consistently) exceed your design output to the margin you waffle on about :-)
There's only so long you can waffle on about having given 110% before it starts to sound awfully clichéed.
On gas turbines, 100% is usually the continuous rating where exceeding it comes with rapidly dimininishing lifespans due to heat/blade stress in the turbines
On electric motors, 100% is usually the continuous rating where exceeding it comes with thermal penalties and you risk melting down the windings/insulation breakdown if the motor overheats(*)
(*) My ancient EV's motor is rated for 24kW continuous, 48kW for 5 minutes or 64kW for one minute. People have tweaked it to get significantly higher output (over 100kW) by bumping up cooling flow and/or limiting peak power duration and/or tighter thermal management - the ultimate limitation is how much torque the gearbox can transmit before self-destructing - it's impressive for being a bog-standard heavy-duty forklift motor at heart)
“A high-voltage connection was not quite perfect. Good enough to pass testing but, when the rocket was flying, the potting compound around the joint melted and liquefied. A short resulted in an electrical spike and "that was the end of that.”
I’m always astonished at the level of detail possible in these post “ the rocket blew up “ events and curious as to how they manage to analyse the exact cause.
Lots and lots of very precise data logging on almost every single channel at multiple points of the vehicle with accurate and synced timing. This makes it possible to trace which signals start getting lost at what time and position relative to one another. This would probably get them close to where they need to be. Then it becomes a deep dive into all data logged during production (measurement reports, photos, etc) to find anything that stands out and formulate theories on what might have failed for what reason. Put all of that together and they can quite accurately tell what is the most likely thing that happened, possibly performing some extra testing to prove or disprove the theories. Sometimes it remains guesswork though.
That too, but I don't think recovery of the fragments from RUD at later stages of flight is usually an option (What with them landing in some of the most remote and deepest bits of ocean of our planet and spreading out over several square kilometers as they tumble down from several dozen kilometers up)
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