SpaceX F9 : SES-10 with reuse of CRS-8 Booster SN/1021 : 2017-03-30 : DISCUSSION

[ChrisGebhardt]

I don't have the time to read through everything, so was this a one or three engine landing burn, how many three engine landings have they done so far isn't it just one?

I'm gonna give an answer... and then it's gonna be wrong.  I believe I caught on the webcast that it was a single engine 30-sec landing burn.  They didn't do a boost back burn, just a short entry and then landing burn.

[ChrisGebhardt]

debut of Roomba

Is the above true? I have not seen evidence it was used

I listened to the presser all the way through now, and it sounded like Elon indicated that it's really only needed in heavier seas.  Apparently, when the water's in a kinder, gentler mood, the stages aren't likely to be jogging around the ASDS, so you don't have a pressing need to get them remotely locked down.

Yes and no.  There's a risk to sending people onto the ASDS to tie down the legs and secure the booster.  The roomba will allow that to happen remotely... in calm or stormy seas.  Basically, in stormy seas, it's absolutely necessary to have.  In calm seas, it's better to have it and secure the booster remotely to reduce risk to personnel even though it's not 100% needed.

[Lars-J]

Maybe they need to BBQ roll the stage for the high heat part of the descent?

Thaicom 8 (another GTO mission) was rock-steady throughout the descent. They seem to be very tightly roll-controlled during the whole launch and landing.

I'm saying maybe they might want to change that... induce a deliberate roll. But that makes the control algorithms more complex I expect.

But... why? It works as intended. You are trying to solve something that is not a real problem. Besides, the grid fins are already being strengthened for block V.

[MarsInMyLifetime]

I don't have the time to read through everything, so was this a one or three engine landing burn, how many three engine landings have they done so far isn't it just one?

I'm gonna give an answer... and then it's gonna be wrong.  I believe I caught on the webcast that it was a single engine 30-sec landing burn.  They didn't do a boost back burn, just a short entry and then landing burn.

And I heard "just a few hundred feet off the deck of the drone ship" which implies the full-brakes, 3-engine suicide burn. Yet I counted about 21 seconds from announced start of burn until the blackout, which resets that distance some. Listen and see what you deduce:
 https://www.youtube.com/watch?v=xsZSXav4wI8?t=1587

[mme]

debut of Roomba

Is the above true? I have not seen evidence it was used

I listened to the presser all the way through now, and it sounded like Elon indicated that it's really only needed in heavier seas.  Apparently, when the water's in a kinder, gentler mood, the stages aren't likely to be jogging around the ASDS, so you don't have a pressing need to get them remotely locked down.

That was not my interpretation. Rougher seas was the motivation for the Roomba.  But I believe once they have it, they'll always use it. It will always be easier/faster than manually jacking, welding and chaining. And it will always be safer.

My $0.02

[Kaputnik]

So at the presser, Elon talked about putting all the lessons of reusability into the 'BFR', as an eventual Falcon replacement. It sounded as though BFR and ITS are not the same thing. Which was news to me. Have I got this right?

[Zed_Noir]

So at the presser, Elon talked about putting all the lessons of reusability into the 'BFR', as an eventual Falcon replacement. It sounded as though BFR and ITS are not the same thing. Which was news to me. Have I got this right?

The BFR or ITS booster is a part of the Interplanetary Transport System. Which also include the ITS Spaceship, ITS tanker and some sort of Martian propellant depot (Musk reply in the SES-10 presser).

[M.E.T.]

So at the presser, Elon talked about putting all the lessons of reusability into the 'BFR', as an eventual Falcon replacement. It sounded as though BFR and ITS are not the same thing. Which was news to me. Have I got this right?

The BFR or ITS booster is a part of the Interplanetary Transport System. Which also include the ITS Spaceship, ITS tanker and some sort of Martian propellant depot (Musk reply in the SES-10 presser).

And, if it is indeed intended to be a replacement for F9, then presumably also some other upper stage variants optimized for orbital cargo delivery.

[Semmel]

Irene Klotz: Do you have other costumers that weren't as brave as SES that are now signed up?  What is life-limiting factor?

Musk: NASA has been supportive.  Commercial, SES has been most supportive.  Next thing is how to achieve rapid reuse without major hardware changeouts.  Aspirations of zero hardware changes and 24hrs reflight.

And how many pages of useless argument whether the goal is "24 hours reflight" or "24 hours done with refurb"?

People assuming that you can't refly in 24 hours because other processes today take too long - a classic "it can't be done since it isn't currently done".

I guess if the stage can be ready to go in 24 hours, other processes will have to catch up so they DON'T remain the bottleneck.

And even if they don't reach the "aspiration" and it becomes 48 hours or even 72 - still enables 1 flight per day with a set of three boosters.

What a fantastic day. And lets hope the next goal of 24h turnaround will not take 15 years. The scepticism of 24h relaunch comes from the fact that its outside SpaceXs sphere of influence. For their satellite constellation, I can believe its possible because they supply the rocket as well as the payload. So there they have control over the entire process and it might be possible for them to pull it off. Would be a big accomplishment if they do!

With an external customer, the process to allow for a 24h turnaround must also apply to the customer. And this is less obvious to accept.

[Steven Pietrobon]

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

[M.E.T.]

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

So about 25 launches to recover the $1B development costs then based on that calculation. Presuming you can keep charging $62m per launch. Which might be difficult, if customers are insisting on reuse discounts.

[AC in NC]

Aspirations of zero hardware changes and 24hrs reflight.

And lets hope the next goal of 24h turnaround will not take 15 years.

Chris' snippet from the Press Conference buried the lede.  The youtube vid link below is cued up to the exact statement.

Press Conference cued to Elon's Statement on 24hr Reflight Target Timeframe

Roughly:  "Our aspirations will be zero hardware changes.  Reflight in 24h. The only thing that changes is you reload propellent.  We might get there by the end of this year but if not this year I'm confident we'll get there next year."

[Hauerg]

...
What a fantastic day. And lets hope the next goal of 24h turnaround will not take 15 years. ...

15 years from the creation of the company !!!

It did NOT take them long, quite on the contrary.

Look what they have done in the 10 years since receiving their NASA contract for F9/Dragon.

Then check what the others have achieved within the last 10 years: Arianespace, Boeing, Lockheed (=ULA), Japan. In total they brought 1 (ONE!) new rocket, the HIIB. All together.

[manoweb]

Then check what the others have achieved within the last 10 years: Arianespace, Boeing, Lockheed (=ULA), Japan. In total they brought 1 (ONE!) new rocket, the HIIB. All together.

They also made Vega

[AncientU]

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

So about 25 launches to recover the $1B development costs then based on that calculation. Presuming you can keep charging $62m per launch. Which might be difficult, if customers are insisting on reuse discounts.

Development cost is likely already retired (or near retired) from corporate reinvestment of all revenue streams.
Bulk of future savings will also be reinvested.

[M.E.T.]

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

So about 25 launches to recover the $1B development costs then based on that calculation. Presuming you can keep charging $62m per launch. Which might be difficult, if customers are insisting on reuse discounts.

Development cost is likely already retired (or near retired) from corporate reinvestment of all revenue streams.
Bulk of future savings will also be reinvested.

Maybe I'm misinterpreting things, but I was thinking more along the lines of how many launches before they have made more money thanks to reuse than they would have made at that point if they hadn't bothered with it at all.

[kevinof]

Don't see why SX would have to give large discounts. If they can (re)launch reliably and they are still the cheapest gig in town and they have spare capacity  then they are in a great position. 

By re-using S1's they increase their margins, free up production and can get a customers payload into orbit very quickly.   Very good position to be in.

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

So about 25 launches to recover the $1B development costs then based on that calculation. Presuming you can keep charging $62m per launch. Which might be difficult, if customers are insisting on reuse discounts.

[uhuznaa]

So at the presser, Elon talked about putting all the lessons of reusability into the 'BFR', as an eventual Falcon replacement. It sounded as though BFR and ITS are not the same thing. Which was news to me. Have I got this right?

The BFR or ITS booster is a part of the Interplanetary Transport System. Which also include the ITS Spaceship, ITS tanker and some sort of Martian propellant depot (Musk reply in the SES-10 presser).

The ITS booster is much too big to serve as a Falcon or even Falcon Heavy replacement. Also Musk calls the ITS just ITS and not BFR.

I have always thought they will sooner or later downscale the ITS concept for a launcher in a more pedestrian payload class with full reusability for both stages. That's the only way to really get down launch costs.

What they will need is a second stage integrated with a payload adapter and fairing that ejects the payload, closes the fairing again and returns to the launch site in one piece. Falcon is too small to do that and ITS is much too large to use it for launching satellites.

[M.E.T.]

Don't see why SX would have to give large discounts. If they can (re)launch reliably and they are still the cheapest gig in town and they have spare capacity  then they are in a great position. 

By re-using S1's they increase their margins, free up production and can get a customers payload into orbit very quickly.   Very good position to be in.

Some notes I took from the presser.

Fairings cost $6M each.

$1B development spent on reuse. Three quarters of the cost to reduce by an order of a magnitude. Thus for $62M expendable, that gives (0.25 + 0.75*0.1)*62 = $20.15M reusable cost.

So about 25 launches to recover the $1B development costs then based on that calculation. Presuming you can keep charging $62m per launch. Which might be difficult, if customers are insisting on reuse discounts.

I agree with this, and have mentioned it before. If others can launch a rocket for $100m, why should SpaceX launch it for less than say $90m, even if it only costs them $20m. Just rake in the $70m profit and invest it in developing ITS.

[Semmel]

Roughly:  "Our aspirations will be zero hardware changes.  Reflight in 24h. The only thing that changes is you reload propellent.  We might get there by the end of this year but if not this year I'm confident we'll get there next year."

Ohh wow, thank you! But lets see. SpaceX has a fantastic pace, but I remain skeptical when it comes to timelines voiced by Elon. Factoring in the Elon dilation factor, its some time in 2019. But doesnt really matter, the feat alone would be most impressive!