SpaceX Falcon 9 : Intelsat 35e : July 5, 2017 : DISCUSSION

[yokem55]

With such performance available, this will not be the last expendable.
 - Ed Kyle

There will be no such heavy payload in the next several months and Falcon Heavy is coming soon.

And it will remain to be seen if reusable falcon heavy is more cost effective than expendable falcon 9. Especially when flying a previously flown booster.

[macpacheco]

As long as F9 boosters are being expended while expanding the F9 performance envelope, I'm actually happy rather than sad.
I look forward to a full Block IV launch with a 7 ton launch and a full Block V with a 7.5-8 ton launch.

[M.E.T.]

With such performance available, this will not be the last expendable.
 - Ed Kyle

There will be no such heavy payload in the next several months and Falcon Heavy is coming soon.

And it will remain to be seen if reusable falcon heavy is more cost effective than expendable falcon 9. Especially when flying a previously flown booster.

Well, in simple terms, if the useful life of a F9 Block 5 turns out to be 10 launches, then a Falcon Heavy fully reusable launch expends 3 of those 10 uses (1 use x 3 boosters = 3 uses), while an F9 expendable launch uses up 10 uses.

Now that equation changes the closer a booster gets to 10 flights. By the time it reaches flight 7, then I guess you could argue that expending it merely costs you the 3 remaining launches in its useful life, which is equal to the 3 uses that the Falcon Heavy rocket uses up between its 3 boosters.

However, if it turns out that the Block 5 can be used 100 times, with reasonable refurbishment after every 10 launches, then it would not make sense to expend an F9 instead of launching a resuable FH until the F9 reaches launch 97 out of 100.

That's my logic, at least. Excluding minimal expenses like fuel costs etc.

[Robotbeat]

If Block 5 is as reusable as SpaceX wants it to be, they can just produce them for a couple years, get a stockpile of them at each launch site, then switch over to just producing upper stages and ITS. When ITS is ready and well tested, just use that. Convert whole factory to ITS and making constellation comm sats and other Mars stuff.

[Nomadd]

If Block 5 is as reusable as SpaceX wants it to be, they can just produce them for a couple years, get a stockpile of them at each launch site, then switch over to just producing upper stages and ITS. When ITS is ready and well tested, just use that. Convert whole factory to ITS and making constellation comm sats and other Mars stuff.

If it's as reusable as they want it to be, they wont need many. Depends on what "minor" refurbishment after 10 flights comes down to.

[alang]

When they've worked their backlog and stop paying penalties then maybe they can focus on reuse more.
Is it possible they are doing deals at the moment where they expend a stage and leave a Comsat with more station keeping fuel in order to reduce the penalties they may be paying?

[Lars-J]

When they've worked their backlog and stop paying penalties then maybe they can focus on reuse more.
Is it possible they are doing deals at the moment where they expend a stage and leave a Comsat with more station keeping fuel in order to reduce the penalties they may be paying?

Hu..what? By that argument they would have done no reuse testing what-so-ever until they were "caught up" with the manifest.

The simple answer is that there is no reuse attempt on this flight because the payload it too heavy. Otherwise they would try to land on a barge.

[meekGee]

Also, am I the only one who likes how the Falcon looks without legs and fins? It's pretty sleek and futuristic, even though it's not recoverable. I don't know, maybe just me.

Yes, I believe you are.

[edkyle99]

Also, am I the only one who likes how the Falcon looks without legs and fins? It's pretty sleek and futuristic, even though it's not recoverable. I don't know, maybe just me.

Yes, I believe you are.

Don't speak for me.

 - Ed Kyle

[edkyle99]

Is 6.7 tons to GTO particularly impressive or unexpected for the Block 3 in expendable format?

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

[meekGee]

Also, am I the only one who likes how the Falcon looks without legs and fins? It's pretty sleek and futuristic, even though it's not recoverable. I don't know, maybe just me.

Yes, I believe you are.

Don't speak for me.

 - Ed Kyle

Yes, but you're a historian...

[Herb Schaltegger]

Is 6.7 tons to GTO particularly impressive or unexpected for the Block 3 in expendable format?

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

[Lars-J]

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

Mass fractions more likely. The F9 upper stage appears to be in a class of its own. 8+ km/s of delta-V is pretty astounding.

[Herb Schaltegger]

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

Mass fractions more likely. The F9 upper stage appears to be in a class of its own. 8+ km/s of delta-V is pretty astounding.

Yeah, true. But face it - that mass-fraction is at least partly due to the use of subcooled prop. It's also a function of designing for first stage re-use (moving dV capability from the first to the second stage).

[macpacheco]

Is 6.7 tons to GTO particularly impressive or unexpected for the Block 3 in expendable format?

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

Except subcooled prop isn't nearly as complex or expensive as full flow hydrogen engines.
For me the Black Magic is how much thrust the M1D has, and the room to stretch/resize the F9 stages there was. I wouldn't be surprised if this was on the radar as the first M1D were being qualified.
Subcooled alone would provided quite limited extra performance, it was the combo of extra thrust, sub cooled, tank resize and minor stretching that created this "Black Magic" beast called F9 Block III/IV !
And to top it all the new F9 stack is quite cheap for its performance and then there's booster reuse. Really mind boggling.

[SLC]

Is 6.7 tons to GTO particularly impressive or unexpected for the Block 3 in expendable format?

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

Except subcooled prop isn't nearly as complex or expensive as full flow hydrogen engines.
For me the Black Magic is how much thrust the M1D has, and the room to stretch/resize the F9 stages there was. I wouldn't be surprised if this was on the radar as the first M1D were being qualified.
Subcooled alone would provided quite limited extra performance, it was the combo of extra thrust, sub cooled, tank resize and minor stretching that created this "Black Magic" beast called F9 Block III/IV !
And to top it all the new F9 stack is quite cheap for its performance and then there's booster reuse. Really mind boggling.

Doesn't the Merlin have a really exceptionally high thrust/weight ratio?  (Can't remember exact numbers)  Is that part of the magic?

[Kaputnik]

Is 6.7 tons to GTO particularly impressive or unexpected for the Block 3 in expendable format?

It is impressive when comparing it to contemporaries.  Atlas 531 can do it, but it takes a staged combustion engine core, a high energy upper stage, and three powerful strap on boosters to get there.  Proton can do it, but it needs four stages (all staged combustion cycle I believe).  Ariane 5 and Delta 4 Heavy and H-2B can do it, but they use boosters and two-stage high-energy cores.  CZ-5 will eventually be able to do it, but we saw today how complicated is that machine.  Falcon 9 does it with just two stages, and no fancy business (RP fuel and straight GG engines).  It seems like black magic or something.

 - Ed Kyle

Subcooled prop (especially lox) = "Black Magic."

Except subcooled prop isn't nearly as complex or expensive as full flow hydrogen engines.
For me the Black Magic is how much thrust the M1D has, and the room to stretch/resize the F9 stages there was. I wouldn't be surprised if this was on the radar as the first M1D were being qualified.
Subcooled alone would provided quite limited extra performance, it was the combo of extra thrust, sub cooled, tank resize and minor stretching that created this "Black Magic" beast called F9 Block III/IV !
And to top it all the new F9 stack is quite cheap for its performance and then there's booster reuse. Really mind boggling.

Doesn't the Merlin have a really exceptionally high thrust/weight ratio?  (Can't remember exact numbers)  Is that part of the magic?

Yes, it's around 150:1, and can go even higher (maybe 200:1?) according to figures Gwynne Shotwell mentioned recently. In a class of its own.

[Comga]

We appear to be wandering from commenting on today's launch

[Kaputnik]

With such performance available, this will not be the last expendable.
 - Ed Kyle

There will be no such heavy payload in the next several months and Falcon Heavy is coming soon.

And it will remain to be seen if reusable falcon heavy is more cost effective than expendable falcon 9. Especially when flying a previously flown booster.

Well, in simple terms, if the useful life of a F9 Block 5 turns out to be 10 launches, then a Falcon Heavy fully reusable launch expends 3 of those 10 uses (1 use x 3 boosters = 3 uses), while an F9 expendable launch uses up 10 uses.

Now that equation changes the closer a booster gets to 10 flights. By the time it reaches flight 7, then I guess you could argue that expending it merely costs you the 3 remaining launches in its useful life, which is equal to the 3 uses that the Falcon Heavy rocket uses up between its 3 boosters.

However, if it turns out that the Block 5 can be used 100 times, with reasonable refurbishment after every 10 launches, then it would not make sense to expend an F9 instead of launching a resuable FH until the F9 reaches launch 97 out of 100.

That's my logic, at least. Excluding minimal expenses like fuel costs etc.

This idea of finite, predetermined number of uses needs to be put to bed. It's a rocket, not a cat.
Every other vehicle (air, sea, or land) is certified fit for use by inspection, not mere hours used. Engines might need deeper level servicing at set intervals, but this doesn't apply to the vehicle as a whole. Subsystems get refurbished or replaced, vehicles get mid-life refits. Retired airframes are parked up in bone yards and used as parts bins.
We already have ample evidence that higher energy flights are more punishing on the rocket. And I for one wouldn't be keen to buy a flight on a rocket that had been deemed ready for its last flight (which is ironic because every other LV out there is always making its last flight...)

[GeneBelcher]

Strongback didn't retract any?