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by sbierwagen 1730 days ago
>highest speeds only at altitudes where the atmosphere is more individual particles than a continuous gas (it's apogee of 62 miles [...] )

Isn't velocity lowest at apogee?

2 comments

I misspoke a bit here. For an orbital vehicle, yes absolutely. Since this vehicle has a relatively shallow suborbital trajectory, I assumed the vehicle has a 1st burn to reach an apogee of ~100km. Upon reaching apogee it orientates itself towards it's earth-bound target, and then executes a second burn. Thus accelerating under thrust towards it's target. Ergo it's maximum speed would occur somewhere between it's apogee and when it re-enters the atmosphere. At least that was my interpretation of the text in the article.
If you assume the Earth is a point mass, then this is relevant. Otherwise, not really.