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Comment by jvanderbot | Hacker News Reader

The two-step sounds precisely like how all forward-moving aircraft land: Rear touch first. The alternative (front touch first) is dangerous for reasons any BMX biker could explain: You're much more sensitive to pitching forward from forward-of-gravity friction.

I wouldn't read too much into that choice.

More likely the velocity was a tad too high.

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But for a propulsive landing, why would they want to have forward velocity at all, unless by design for this type of landing ? I'd have thought the preference would be to kill forward speed and land vertically.

As an experienced KSP crasher, you never completely cancel horizontal component, so you need a way to dissipate it. And it's easier to dissipate if you know which direction your horizontal component is, which is easier to do when its value isn't so close to 0.

That being said I perfectly see how sub-ms automated command could make what I said wrong.

One of two main engines blew off at ~50m and the craft was essentially in a cross-wind landing, likely without de-crab. Having lateral velocity wasn't a part of the plan.

The engine loss was a detail in the article that I hadn't seen anywhere else in the commentary and speculation on the landing. Even now many commenters don't seem to be taking this into account. Even if there was redundancy built in, an engine loss makes things much more difficult. I can see why they're claiming 100% success despite being upside down.

> The two-step sounds precisely like how all forward-moving aircraft land: Rear touch first. The alternative (front touch first) is dangerous

That's why I was never comfortable stopping in rollerskates or ice stakes.

I never understood why those use front-brakes instead of rear-brakes like the roller blades I had as a kid. The latter I could comfortably use almost instantly, the former, I never got comfortable with.

I assume that you just drag the tip of one skate behind you, rolling on the other until you lose momentum. And having the ability to suddenly stop is akin to ice figure skates, with the pointy bits at front.

Taildraggers would like a word....

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