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Friday, April 28, 2023

Between Games of a Double Header

The baseball analogy is the best I can think of for the situation right now.  We were set to get a rare combination this evening: two launches by SpaceX within two hours and small change.  

  • Falcon 9 Block 5 carrying O3b mPOWER 3 & 4 from SLC-40 at Cape Canaveral SFS at 5:12 PM ET  followed by 
  • Falcon Heavy carrying ViaSat-3 Americas & Others from Kennedy Space Center at 7:29 PM ET. 

Two launches two hours and 17 minutes apart from two launch complexes 3.6 miles apart.  

This has been a bad week for good weather and thanks to the resulting launch scrubs, these two launches have rolled here from Wednesday.  After other problems moved them to Wednesday from earlier in the month.   

The first launch was delayed an hour until 6:12 PM and went as smoothly as can be.  The booster landed nine minutes later on Just Read The Instructions.  The well-used booster's landing marked the 188th successful landing of the orbital-class Falcon 9 boosters.

The second part of the double header is a Falcon Heavy launch of the ViaSat-3 communication satellite, intended to provide increased coverage over North and South America, at up to Terabit/second rates. The launch is also carrying two other payloads, a telecommunications satellite named Arcturus, built and operated by Astranis Space Technologies to provide internet coverage in the remote regions of Alaska. The third is a cube sat called G-Space 1 that will host multiple payloads.  

This will be the fully expendable configuration of Falcon Heavy, which has never flown before.  A close look at the side boosters will reveal they have no grid fins or landing legs.  

The Falcon Heavy dedicated to the ViaSat-3 mission during an interval when it wasn't raining or cloudy.  Richard Angle photo for Teslarati.

Readers can't tell this but there's about a 20 minute gap in writing this from the bottom of the first picture to here.  The reason was to watch the Falcon Heavy launch, but that went into a hold called by the software controlling the countdown at T-59 seconds.  

The second game of the double header has been called off.  Hey, that happens in baseball (I think).  It will probably be rescheduled for 24 hours, and more likely tonight's original 7:29 than the 8:28 it turned into. 



4 comments:

  1. At least there was no big oops. Better a delay than a failure since this is a first flight for this configuration of Falcon Heavy.

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  2. And from what I see, the booster landed dead center in the landing circle.

    I remember a bit about control systems, from an earlier life. Finding the ship in the ocean is one thing, actually executing a landing on a moving target in the ocean is simply amazing but to hit the circle dead center is almost beyond belief.

    This is the future that I want to live in.

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    1. Part of the system makes it even more remarkable. Falcon 9 can't hover - even one engine at partial throttle is too much thrust and they can't be throttled any lower. Which says they can't slow to zero, hover above the deck, make sure they're where they want to be and then turn down thrust a little. Maybe slide sideways, a little as they gently go the last few yards. It's moving the whole way down.

      What they do is calculate where they should slow to the point they have to turn off the engine. Ocean swells can't be accounted for, so sometimes the ship is higher than calculated for and they slam into the deck before they expect to; other times its lower than expected and they drop more than expected.

      I think their accuracy is really pretty amazing.

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    2. Don't forget, they also maintain the Z axis when landing. Have you noticed?
      That is why they can reach out with the chopsticks and grab the Starship and or Booster when they "land" - they have that much control!

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