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You'd think they'd want some redundancy though. Do they really do it only based on GPS, or do they have other optical/radar/radio systems? Also does the US gov
by tlrobinson 11y ago
You'd think they'd want some redundancy though. Do they really do it only based on GPS, or do they have other optical/radar/radio systems?
Also does the US government give SpaceX access to the military GPS signals?
- jccooper 11y agoIt has very good inertial guidance as well. The GPS is probably the best available; considering they launch GPS satellites, I'd expect they aren't restricted. However, civilian GPS use isn't really much different anymore; intentional degradation was turned off in 2000, though certain dynamic limits still apply on the receiver side.
- mikeash 11y agoI don't know if they care too much about redundancy. The landing is still very much optional, after all. They have no redundancy in case of engine failure for this phase, which is probably much more likely. GPS is kind of inherently redundant anyway, as long as you have multiple receivers. You need four satellites for positioning, but way more than that are visible at any given time.