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jacquesm

History was being made today. Super, congratulations to all of SpaceX. Now let's see the landing :)

STUCK THE LANDING :) :) :)

Apologies to my neighbors who I surely woke up.

Hah :) Incredible! Now, will they fly this one again?

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That cut to black nearly gave me a damn heart attack haha. Satellite connection lost because rocket exhaust is basically a giant ionized cloud of noise.

Elon looks like he hasn't been getting enough sleep or showers, and like he's about to back flip and start happy crying.

You could see the flicker of the rocket exhaust reflecting on the panel at the back of the drone ship in the split feed so it was at least extremely close when it cut off. Probably the rocket exhaust interfering with the transmission as well as the blast simply pushing the platform out of alignment.

My heart attack moment was during the launch when I started seeing flame flickering around the tops of the engines... and then I thought to look at the altitude indicator, and realised they were at about 10km, and it was just the plume expanding as the atmospheric pressure dropped.

I got extremely worried when I saw that happen too. I didn't even think to look at the altitude indicator.

I got extremely worried as well and it wouldn't have made a difference looking at the altimeter because I have no idea about how rocket engines behave.

The flames around the top of the engines is normal, it's the exhaust from the turbo pumps feeding the main engines.

Check this page, the Merlin uses an open cycle, where fuel/oxidizer used to fuel the pumps is just dumped overboard.

https://en.wikipedia.org/wiki/Gas-generator_cycle

This picture clearly shows both exhausts: https://en.wikipedia.org/wiki/Merlin_(rocket_engine_family)#...

For some reason that effect was much more pronounced during this flight (at least in the video) than in previous launches that I watched. Maybe it was because of the camera angle looking more at the side of the rocket when usually you are looking more at the bottom.

Yeah, it's normal, and it usually ends up getting sucked backward, presumably due to the turbulent airflow in the space between the end of the vehicle and the engine nozzles:

Echostar: https://youtu.be/zEfEBJfD_RE?t=18m23s

JCSAT: https://youtu.be/QZTCEO0gvLo?t=17m38s

CRS-9: https://youtu.be/ThIdCuSsJh8?t=17m45s

Bit worried myself, One of those grid stabilisers on the first stage was definitely melting on the way back (@26mins on Youtube) just before first stage camera went on the fritz.

It just got covered in soot from the ablative protection (okay, probably some Al2O3 too, from the subsequently burning grid fin) on the grid fins burning off. GTO/GEO missions come in _really_ hot!

> Apologies to my neighbors who I surely woke up.

Of Course They Still Love You ;).

Nicely done there! Gotta love that a company turning science-fiction into less fiction and more science would name their drone ships after the Culture series. Pretty sure Elon Musk is far for the only person there finding these books inspiring.

> Now, will they fly this one again?

Probably not. For starters, Elon has said they only intend to get a few flights out of the Block 3 rockets. Additionally, the CTO of SES said Gwynne promised them some bits of the rocket for posterity.

The Block 5 rockets (to fly later this year) are the ones Elon expects to fly more or less indefinitely, with regular servicing and part replacement.

Elon gave more details regarding reusability during the post launch press conference:

10 launches without maintenance

100 launches with moderate maintenance

They are aiming for 1000 launches for their upcoming ITS.

In the Post-Mission Press Briefing [1] Elon Musk said SpaceX will gift the stage to "the cape" (so either NASA Kennedy Space Center or the CCAFS) because it's historic. Also, they don't need to keep the Block 3 cores, they want to transition to Block 5 as soon as they can to get the 7 flights of a frozen configuration of Block 5 to get certified for flying people.

1 - https://www.youtube.com/watch?v=jC3LQFpuzqs

My Dad who is his seventies calls me every time they launch and tells me how the landing went. I get the feeling he might be waking the neighbors too. I honestly think my nephew dreams of rockets because of his grandpa.

And they caught it again. Truly amazing.

Sitting here smiling ear to ear :) Also interesting how many references there were to the Mars mission in the lead up to the launch.

Amazing. But the video seemed to cut out right before landing.

They warned that would happen, the real time coverage is a good show of confidence.

It always happen right after you can barely see the fire reflecting on the barge. The vibrations from the rocket screws with the satellite connection.

We don't have the technology yet to have internet in the middle of the ocean without satellites.

Why not have a small secondary ship parked about a mile away, that can act as a satellite relay? Should be able to maintain a good link over that small distance.

Ultimately they're a space launch company, not a TV channel :)

That's adding a lot of extra cost just to keep a live feed for going for the missing ~15 seconds around the landing.

Wonder if they will be able to launch it a third time, though, since it seemed it did get a bit more damage on entry this time around. Either way, impressive.

Btw, does anyone know how reusable these things are expected to be in the near term? As in, would a perfected Stage 1 be expected to be able to fly 10 missions? 100? 1000?

Headed to a museum, probably, after some testing.

I'm pretty sure the plan is to put this one in a museum. Later variants are supposed to be easier and more reliable to re-fly.

Something to think about: pretty soon there will be nothing strange about a rocket that has flown before. Contrast it with the feeling you have for a 737 that has done 2500 starts and landing prior to you going on board, it's a sign of confidence that it did that. Now it will be many many years before there will be boosters with numbers of take-offs and landings > 20 or so but at some point insurance premiums for unflown hardware will be higher than for hardware that has been flown before.

Huge game changer this, also in the frequency of launches.

"Flight tested" rockets is an interesting spin on this

As is, on the other end of the spectrum, "lithobraking" :)

>737 that has done 2500 starts and landing

You can probably add another zero there. 737 airframes don't even need a special inspection and maintenance program until they hit 60,000 takeoff/landing cycles. [1]

[1] http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf...

On the prelaunch video, they suggeste a try for at least 10x.

... for Block 5, which is the next version after this one. They've learned stuff since they started landing and examining them. First Block 5 launch is perhaps the end of this year.

They covered it in the webcast, they said they expect 10 cycles. Not sure which block/version they are talking about though.

This comment was very informative https://news.ycombinator.com/item?id=13999791

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