What is the cost to NASA per launch to ISS of Starliner vs Crew Dragon?
According to a 2019 report by NASA's Office of the Inspector General (OIG), the launch costs are (in million\$):
cost per astronaut
cost per launch
SpaceX Crew Dragon
Boeing CST-100 Starliner
So, out of the three vehicles currently being used to ...
Crew Dragon uses the regular Draco thrusters for the deorbit burn, and in fact for any burn during a regular flight. The Superdracos are only used for launch escape.
The main reason is that the Superdracos are too powerful. A deorbit burn with the Superdracos takes only a couple of seconds, which means that if they burn a little bit too long or too short, ...
Say a Falcon 9 experiences an in-flight failure where four core engines shut down prematurely. Would it still be feasible to jettison the upper stage and attempt to reach orbit, while trying to land the booster?
It's unclear to me, given the phrase "attempt to reach orbit", if you mean discard the upper stage or separate it as usual. As Jörg W ...
A big part of the problem is that the first stage is also very close to exiting the communications range from the Cape, and is losing altitude rapidly, tucking itself behind the horizon in the process.
Note that the second stage comms has by then already been handed over to Bermuda, as it is a good bit further downrange.
When the Falcon 9 is returning to ...
Let's look at what umbilicals are on SLS, a fairly traditional and very large rocket. It has two stages and two boosters and a crewed capsule. It uses cryogenic liquid oxygen and hydrogen for fuel.
Two aft skirt electrical umbilicals, or ASEUs, will connect to the SLS rocket at the bottom outer edge of each booster and provide electrical power and data ...