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It crashed and the aftermath was photographed. https://www.space.com/mars-perseverance-rover-photo-sky-crane-crash A moment of respect for the descent stage. Within two minutes of safely delivering me to the surface of Mars, I caught the smoke plume on one of my Hazcams from its intentional surface impact — an act that protected me and the scientific ...


22

This NASA doc explains fairly clearly why the skycrane system was used: Why not rockets, like the Viking missions? "With a payload this size, the rockets could kick up enough dust to compromise the rover and its instruments," explains Sell. "And the rockets could excavate craters Curiosity would have to avoid as it drives away. Add to that the risk of a ...


13

tl;dr: With technology, anything can potentially go wrong at any moment. Simplify and minimize wherever possible. Keep your eye on the prize. Run away! As soon as the "cord is cut" the crane represents an imminent threat to the \$2.75 billion rover in several ways. It's hydrazine monopropellant engines have hot, nasty, reactive, horrible exhaust ...


12

That's correct, they're hydrazine monopropellant thrusters. Per Wikipedia: Each rocket thruster, called a Mars Lander Engine (MLE), produces 400 to 3,100 N (90 to 697 lbf) of thrust and were derived from those used on the Viking landers. The citation links to an Aerojet press release which contains a little more information: After deployment of a ...


7

Retrorockets could accelerate dust particles and smaller stones to a lot higher velocities than highest recorded wind gusts on the surface of Mars that reached 500 to 600 km/h (300 to 375 mi/h). For example, the Apollo Lunar Modules' descent engines blew out high-velocity lunar particles estimated to have reached speeds of between 0.6 and 1.5 miles per ...


6

The skycrane fed the cables out from a spool contained in the Bridle and Umbilical Device (BUD). As the DS maintains a constant vertical velocity of 0.75 m/s, the rover is lowered on a triple bridle to 7.5 m below the DS through the use of an electromagnetic brake connected to a spool containing the three bridles. All of the bridles pass through a ...


4

Yes, the skycrane was able to fly in a certain direction. Once the rover was on the surface and the bolts were cut, the skycrane was programmed to angle itself forwards or backwards, whichever way was closer to North, and fly that way. This was to ensure that the rover wouldn't be damaged by the rockets going over it. You can hear Al Chen, the EDL lead, ...


3

The novel solution the MSL team has developed is what they refer to as a “sky crane.” After reducing its speed through a combination of atmospheric friction, parachute, and retrorockets, a descent stage with Curiosity hanging from it in a bridle of nylon tethers will use its thrusters to essentially hover as it lowers the rover to the surface— “a way of ...


3

The sky crane engines were tested individually. This is common practice for small thrusters like the ones used in almost every launch vehicle and satellite, where test firings of the whole assembly are impractical. Other subsystem tests looked at the interaction between the engine exhaust and Mars' soil, for instance. Full-up tests are difficult. You need ...


2

What was going to on Mars was only the rover, all the remaining parts were "support garbage" to be disposed. Sycrane/descent stage does not even have a flight computer: it was driven by rover brain! After umbilical cut, a very simple logic onboard DS was activated: "fly up for some seconds, then turn." Engine is not even controlled, it ...


1

A lowering system was present on the SC. So the cable doesn't interfere with Perseverance. Also, you can see on Perserverence's pictures thoses cables cutted. This picture is from Curiosity but the technique was the same. From What was the use of these cutted cables? click for larger


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