SpaceX Starship - Orbital Test Flight - Starbase TX

Launch Date: April 20
Launch Window: 8:28am CDT (6:28am PDT, 13:28 UTC) - 62 minute window
Launch site: LC-1? - Starbase, Boca Chica Beach, Texas
Core Booster Recovery: Expended in Gulf
Starship Recovery: Water landing near Hawaii
Booster: Super Heavy Booster 7
Starship: Starship 24
Mass: No mass simulator mentioned
Orbit: LEO-ish
Yearly Launch Number: 26

A SpaceX Super Heavy and Starship launch vehicle will launch on its first orbital test flight. The mission will attempt to travel around the world for nearly one full orbit, resulting in a re-entry and splashdown of the Starship near Hawaii.

Webcast:

 

[zoomer0056]

At 9:35 he says,

"the booster rotation is beneficial anyway as it has to start rotating anyway to start the belly flop maneuver to reduce speed by air friction"

Huh? How could he get confused with the belly flop maneuver of Starship and with the traditional landing of booster? Doesn't bode well on how much I should take the rest of his explanation seriously..

View attachment 942538

Good point.

 

[ecarfan]

How could he get confused with the belly flop maneuver of Starship and with the traditional landing of booster?

Yes, I noticed that too, but the booster does come in at an angle to increase aerodynamic drag, so while it’s not really the same bellyflop maneuver, as starship, there is some similarity.

 

[Electroman]

The F9 booster does that today?

 

[ecarfan]

The F9 booster does that today?

Yes.

 

[JB47394]

the booster does come in at an angle to increase aerodynamic drag

Also to produce lift to provide cross-range capability. I would consider "belly flop" to be a poor term to use for the booster's maneuver. I believe "skidding" is the term use in aerodynamics.

 

[JohnnyEnglish]

Yes, I noticed that too, but the booster does come in at an angle to increase aerodynamic drag, so while it’s not really the same bellyflop maneuver, as starship, there is some similarity.

Whilst the booster is at an angle to the vertical it is not at any significant angle to the direction of airflow post entry burn. Aerodynamic drag is not significant prior to entry burn. The booster orientation (and direction of the airflow) becomes closer to the vertical post entry burn as the booster horizontal velocity component bleeds off due to the drag generated by the grid fins.

 

[Electroman]

Whilst the booster is at an angle to the vertical it is not at any significant angle to the direction of airflow post entry burn. Aerodynamic drag is not significant prior to entry burn. The booster orientation (and direction of the airflow) becomes closer to the vertical post entry burn as the booster horizontal velocity component bleeds off due to the drag generated by the grid fins.

That’s what I thought, which makes the observation by that YouTuber on Booster’s orientation inaccurate.

 

[mongo]

Could they have just had a slip of the tongue and meant to say 'boost back' instead of 'belly flop'?

 

[Electroman]

Could they have just had a slip of the tongue and meant to say 'boost back' instead of 'belly flop'?

More like it.

 

[JB47394]

Could they have just had a slip of the tongue and meant to say 'boost back' instead of 'belly flop'?

Except that he said "belly flop maneuver to reduce speed by air friction". To me, that says "I confused Starship with the booster". For someone who is focused on the physics of two separating stages during rotation, I'll give him a break on that. It doesn't factor into the explanation, which I quite enjoyed. He underscored the importance of the change in center of mass of the system and how that plays a role in where the two stages go during the maneuver. Nicely done.