You're confusing "plan" with "reality". Plan is for block 5 to be the final revision. But no one (not even SpaceX) knows if that will be "reality" yet. Wait and see. Perhaps the first block 5 will live up to expectations in every possible way.
When will the first block 5 fly? Also, is the first block 5 Falcon Heavy being built, yet?
Quote from: Robotbeat on 12/31/2017 01:04 pmWhen will the first block 5 fly? Also, is the first block 5 Falcon Heavy being built, yet?Unknown and unknown. There is some L2 insight as to which core will be the first Block 5 but it is very speculative right now as to which launch will use that core.
...My sources at SpaceX tell me that SpaceX has (significantly) more than three Block 5 boosters in various stages of construction, with many more to come....
SpaceX has already explored the flight envelope pretty thoroughly with Block 3/4. They won't be asking Block 5 to fly much hotter reentries than the GTO missions they've already landed (because FH). They have a decent sample of post-GTO landed boosters to evaluate in order to set requirements for Block 5. I'd be surprised if they underperform on Block 5 reusability. Customer acceptance is a somewhat different story, but because of how surprisingly well Block 3/4 performed on those marginal GTO landings, SpaceX really has no excuses for failing to deliver a workhorse Block 5.
Quote from: cppetrie on 12/31/2017 02:24 pmQuote from: Robotbeat on 12/31/2017 01:04 pmWhen will the first block 5 fly? Also, is the first block 5 Falcon Heavy being built, yet?Unknown and unknown. There is some L2 insight as to which core will be the first Block 5 but it is very speculative right now as to which launch will use that core.Once they do fly Block 5 they will probably want to fly only that until crew dragon launches, in order to build up flight history, then use up as many block 3/4 as practical before retiring them.
So Musk said the STP FH mission will be all Block 5, but they haven't announced the first F9 mission unless I missed it. That's what I'm most excited for now. To see what a rocket looks like that is built rugged, with expensive materials because they know they can amoritize the cost. Musk made it very clear how expensive the titanium grid fins are, how it's only reliable reuse that makes their use economical. I want that first reflight, then the 2nd, 3rd, 4th... and to find out how many boosters they really need.
How many boosters they need will largely depend on how fast they can turn them around. The faster they can turn them around the less they need.I'm sure they'll start out slow and cautiously to start with the Block 5's.Seems like maybe May before we see a Block 5 fly.
I want that first reflight, then the 2nd, 3rd, 4th... and to find out how many boosters they really need.
Quote from: Norm38 on 02/07/2018 05:08 pmI want that first reflight, then the 2nd, 3rd, 4th... and to find out how many boosters they really need.I wonder if they take the "self-insurance" opportunity with Starlink payloads to just run up gaudy numbers of same-core reuses and turnaround times to get real empircal results on the books to prove what they have.
Quote from: butters on 12/30/2017 04:45 pmSpaceX has already explored the flight envelope pretty thoroughly with Block 3/4. They won't be asking Block 5 to fly much hotter reentries than the GTO missions they've already landed (because FH). They have a decent sample of post-GTO landed boosters to evaluate in order to set requirements for Block 5. I'd be surprised if they underperform on Block 5 reusability. Customer acceptance is a somewhat different story, but because of how surprisingly well Block 3/4 performed on those marginal GTO landings, SpaceX really has no excuses for failing to deliver a workhorse Block 5.Hotter ?I think Block 5 re-entries will be cooler.Re-entry burn starts a few seconds sooner plus the higher thrust, so peak heating is lower, even if re-entry starts a bit faster.AMost extra performance is used on the way up, but certainly some is saved for re-entry.The upper stage also has more performance too. All of that goes to the payload orbit.The whole point of Block 5 is no more re-entries too hot to reuse.
Quote from: macpacheco on 12/31/2017 11:25 pmQuote from: butters on 12/30/2017 04:45 pmSpaceX has already explored the flight envelope pretty thoroughly with Block 3/4. They won't be asking Block 5 to fly much hotter reentries than the GTO missions they've already landed (because FH). They have a decent sample of post-GTO landed boosters to evaluate in order to set requirements for Block 5. I'd be surprised if they underperform on Block 5 reusability. Customer acceptance is a somewhat different story, but because of how surprisingly well Block 3/4 performed on those marginal GTO landings, SpaceX really has no excuses for failing to deliver a workhorse Block 5.Hotter ?I think Block 5 re-entries will be cooler.Re-entry burn starts a few seconds sooner plus the higher thrust, so peak heating is lower, even if re-entry starts a bit faster.AMost extra performance is used on the way up, but certainly some is saved for re-entry.The upper stage also has more performance too. All of that goes to the payload orbit.The whole point of Block 5 is no more re-entries too hot to reuse.I think you have understood wrongly where the extra performance comes from.The engine thrust increase won't give big extra performance because the amount of fuel is not increasing, it only gives slight decrease in gravity losses.AFAIK considerable part of the "increased performance" of block 5 comes comes from less fuel used for re-entry and landing.
Quote from: hkultala on 02/08/2018 07:47 amQuote from: macpacheco on 12/31/2017 11:25 pmQuote from: butters on 12/30/2017 04:45 pmSpaceX has already explored the flight envelope pretty thoroughly with Block 3/4. They won't be asking Block 5 to fly much hotter reentries than the GTO missions they've already landed (because FH). They have a decent sample of post-GTO landed boosters to evaluate in order to set requirements for Block 5. I'd be surprised if they underperform on Block 5 reusability. Customer acceptance is a somewhat different story, but because of how surprisingly well Block 3/4 performed on those marginal GTO landings, SpaceX really has no excuses for failing to deliver a workhorse Block 5.Hotter ?I think Block 5 re-entries will be cooler.Re-entry burn starts a few seconds sooner plus the higher thrust, so peak heating is lower, even if re-entry starts a bit faster.AMost extra performance is used on the way up, but certainly some is saved for re-entry.The upper stage also has more performance too. All of that goes to the payload orbit.The whole point of Block 5 is no more re-entries too hot to reuse.I think you have understood wrongly where the extra performance comes from.The engine thrust increase won't give big extra performance because the amount of fuel is not increasing, it only gives slight decrease in gravity losses.AFAIK considerable part of the "increased performance" of block 5 comes comes from less fuel used for re-entry and landing.Amount of fuel loaded depends on LOX and helium load times among other factors, we don't know that it won't be higher than Block 3&4.