SpaceX Falcon 9 historic landing thread (1st landing attempt & most recent missions)

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boatgeek

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I 100% forgot that the NS is intended to separate not too long after MECO. According to a flight test video here, it separates at ~1760 MPH and 240K feet in normal flight. So the top of the booster is obviously designed for supersonic flight without the capsule, though in very thin air. Incidentally, Max Q for NS is subsonic, at 565 mph at 23K feet.
 

Mushtang

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I 100% forgot that the NS is intended to separate not too long after MECO. According to a flight test video here, it separates at ~1760 MPH and 240K feet in normal flight. So the top of the booster is obviously designed for supersonic flight without the capsule, though in very thin air. Incidentally, Max Q for NS is subsonic, at 565 mph at 23K feet.
Yep, the "very thin air" you mentioned is the key difference. New Shepard separated in that video at 240,000 feet up where Dragon and Falcon 9 will separate on this test around 65,000 feet. Air is much thicker, stresses will be much higher, fireball will be.... ?
 

georgegassaway

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And if not Sunday, them Monday, same timeframe.

Webcast:
 

pyrobob

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Managed to tune in about 45s into launch. Very cool.
 

les

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Success!
And nice CATO of the booster.........
 

BEC

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Will be interested to hear if they blew the booster or it blew naturally. My guess was they blew it.
According to the commentary they expected it to start to tumble and then break up under aerodynamic forces. They were not planning to use the FTS. And it certainly looked like it wasn’t necessary.
 

0011001100

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Will be interested to hear if they blew the booster or it blew naturally. My guess was they blew it.
According to the commentary they expected it to start to tumble and then break up under aerodynamic forces. They were not planning to use the FTS. And it certainly looked like it wasn’t necessary.
If you watch with a large screen carefully the booster begins to bend about 1/3 of the way from the top before exploding.
 

Mushtang

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Whenever I read about the upcoming Dragon Abort Test everything said it was going to fire at Max-Q. This morning Max-Q happened about 60 seconds in, and the Dragon didn't pull away until about 30 seconds later, and after they'd throttled back up. It seems like the test was at a much lower pressure by that time.

So I wonder if the abort signal was sent late for some reason, or if maybe the pre-flight articles reported on bad information given out before hand and the test was always planned for that far after Max-Q?
 

MichaelRapp

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Scott Manley did a decent video on the event.
"Of course, portrait video is a crime against humanity, so I am going to rotate this 90 degrees...." lol

I only discovered Scott's videos just yesterday when I was researching background for this launch. I like his stuff!
 

Chad

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Scott Manley did a decent video on the event.

is it me or was the water deluge system late to turn on at launch? The motors were completely lit and throttled up before they came on 100%. My understanding is the water protects the rocket from sound waves echoing off the pad just as much as it protects the pad from the exhaust.
 

cvanc

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is it me or was the water deluge system late to turn on at launch? The motors were completely lit and throttled up before they came on 100%. My understanding is the water protects the rocket from sound waves echoing off the pad just as much as it protects the pad from the exhaust.
I watched it again and it seems you are correct; the water system had a different timing than past launches. It was much later in the ignition sequence and had a strong 'startup surge' that I don't recall seeing before?

...And yeah it really looked like it started quite a bit later than would be ideal.
 

dhbarr

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I watched it again and it seems you are correct; the water system had a different timing than past launches. It was much later in the ignition sequence and had a strong 'startup surge' that I don't recall seeing before?

...And yeah it really looked like it started quite a bit later than would be ideal.
This would be a great test to run on a booster you weren't planning on getting back.
 

OverTheTop

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Maybe they turned the deluge on later so there was less steam blowback and the venturi effect kicked in earlier. This would potentially be easier on the tail end of the rocket.
 

mpitfield

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T +38:43, what is up with the sudden velocity change of stage two? Did they do a quick burn or was that just a counter reset.
 
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