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Comment by ForHackernews | Hacker News Reader

> however the software in the capsule did not include any provisions for parachute deployment in this situation.

That seems like a pretty significant oversight?

It wasn't an oversight. It was intentional. The Dragon v1 is designed solely for cargo. It has no launch escape system and its software does nothing while it's going up[1]:

> The software in this cargo version of Dragon (Dragon 1), Musk explained, is inert on ascent and was not programmed to release the parachute in the event of a failure. Software in the version of Dragon under development for taking people into space (Dragon 2 or Crew Dragon) is programmed to do just that.

While it sounds like simple thing, remote control of the 'chutes would add significant complexity and cost.

1. http://www.spacepolicyonline.com/news/failed-strut-likely-ca...

Also, you generally want as many systems "off" as you can manage during the flight. There's just less that can go wrong if there is less going on.

And remember to set your SCE to aux.

I know what that is!!!!

That was actually a very interesting read.

http://motherboard.vice.com/read/john-aaron-apollo-12-curios...

"But Bean, who was sitting in the right seat, just in front of the switch, remembered it from the sim the previous year."

I guess we can forgive Bean for frying the color TV camera, then.

No one expected Dragon to survive those conditions, so they never bothered adding that code. It's just a cargo ship, so it doesn't really matter.

After having learned in real world conditions that it can handle those sorts they figured, what the heck... might as well add it.

The crewed Dragon (Dragon 2) uses powered thrusters to push itself away from a failing rocket.

Water landings only work if you design for them which is a lot of extra weight. Catching the thing in the air is difficult because you get very little warning and they can land in a huge area.

Net result, failed launches are not really worth trying to recover unless it's people. Though, deploying parachutes may have marginally reduced the risks to a passing boat.

Dragon already lands on water, so there's no technical reason it couldn't do it after a launch vehicle failure, if the event was survivable. Now we know that such a scenario exists, but that was not obvious before.

My understanding is Dragon 1 does not float fully loaded. It can get 3,10 kg ISS used and dispose of 3,10 kg of waste, but only to recover ~2,500 kg. https://en.m.wikipedia.org/wiki/Dragon_(spacecraft)

Make that "3,310 kg ISS" not "3,10 kg"

I believe the difference between up and down cargo is because the trunk is dropped and burns up on entry, only the pressurized capsule itself lands.

> Though, deploying parachutes may have marginally reduced the risks to a passing boat.

Didn't it fall in the range safety exclusion zone, which ships were warned away from?

It wasn't an oversight - they launched the mission with the understanding that their parachute software wasn't ready and the risk was acceptable since it was uncrewed. I seem to remember reading that their parachute hardware was ready to go if absolutely necessary, but they wanted to make sure the software was locked down.

Not necessarily, if there was no reason to recover it

(I'm not sure if there was a reason or not)

Move fast and crash things!

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