What is the maximum apogee a Crew Dragon can reach in a highly elliptical orbit (by both the Falcon 9 and the Falcon Heavy)? There is a planned touristic mission in which the current apogee record of 1,368 km (788 mi) set by Gemini 11 is to be broken.

  • $\begingroup$ Gemini 11 was Altitude: 1368.9 km (739.2nm) (from science.ksc.nasa.gov/history/gemini/gemini-xi/gemini-xi.html) What kind of miles are the 788 mi? $\endgroup$ – Uwe Jun 29 '20 at 9:22
  • $\begingroup$ @Uwe What a question. Statute miles (land miles) of course. I wonder why they (and the WP article too) use nautical miles. $\endgroup$ – LoveForChrist Jun 29 '20 at 10:12
  • $\begingroup$ first: Seeing as it could be lifted into a flight path such as the RedRoadster has, maximum apogee has little meaning. Second, please don't post multiple "max apogee" questions when one question regarding basic rocket and orbital mechanics equations would suffice. $\endgroup$ – Carl Witthoft Jun 29 '20 at 11:04
  • $\begingroup$ There is a long tradition at NASA to use nautical miles and not land miles. Navy and airforce use nautical miles too. The first NASA astronauts were aircraft test pilotes and used to nautical miles. $\endgroup$ – Uwe Jun 29 '20 at 11:07
  • $\begingroup$ @CarlWitthoft Apogee is concerning the Earth's orbit. The Tesla Roadster is in orbit around the Sun where you'd say aphelion/perihelion. The car is lighter than a Crew Dragon so that it can be put at escape velocity but the Crew Dragon is a different story. I dunno whethere it can be flown to escape velocity by the Falcon Heavy. It are different rockets/orbiter than the STS, and therefore can't be put into the same question. $\endgroup$ – LoveForChrist Jun 29 '20 at 11:07

Crew Dragon with Falcon Heavy can theoretically be sent to a lunar free return trajectory, so pretty much any apogee could be done. As for just a Falcon 9, it's hard to know for certain. Putting in a desired orbit of 2000 km with the NASA Performance Vehicle Calculator, I got the following plots. Note that 9000 km is the launch mass of Crew Dragon.

enter image description here

The problem is that the flight profile for a human rated spacecraft has the potential to interfere with this. I'm going to make the assumption that if you can do a RTLS, you can do a human rated trajectory with a drone ship landing. The real answer is probably somewhere between the lines.

So I'm going to guess they can set the record, but probably not by a huge margin. Definately less than 2000 km, probably around the 1400-1700 km range.


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