With a turnaround time of 4 weeks you only need 4 S1s 1046-1050 to provide for launches for an entire year period. During the next year we may see just a couple more S1s built. This includes a center core FH version and another core possibly a second FH as insurance or for customer that demands a new core (and pays extra for it).
Quote from: oldAtlas_Eguy on 09/11/2018 10:54 pmWith a turnaround time of 4 weeks you only need 4 S1s 1046-1050 to provide for launches for an entire year period. During the next year we may see just a couple more S1s built. This includes a center core FH version and another core possibly a second FH as insurance or for customer that demands a new core (and pays extra for it). They're not going to shut down because an ASDS breaks down or for any other reason they don't recover a core. They're also not going to ignore the possibility that the methane fleet could take longer than anticipated. There will be plenty of boosters built.
I kinda figure on a someday fleet of about 12 active boosters and 4 more inactive...2 - NASA Crew and RTLS only... dedicated usage2 - NASA Cargo and RTLS only... dedicated usage2 - FH cores (one active, one spare)2 - FH side boosters (one pair always set up as needed)2 - East coast GTO active fleet...2 - West coast SSO active fleet...4- inactive in heavy overhaul or as new or rebuilt spares for last 6 above...A Starlink launch campaign would likely add 4 more boosters and really amp up the flight rate...May never see a booster number 1080 or beyond is my guess... Plenty of S2's flown I bet by 2026 or so... (will not end up reusing S2 except MAYBE a Starlink dedicated setup)BFR/BFS slowly take on all the work and the F9 fleet shrinks to a handful active...2 cents on subtopic...
The booster moving on 401.
From the images shown in this post of the recent returned B5 booster:Quote from: cygnusx112 on 09/15/2018 07:06 pmThe booster moving on 401.It seems the transporter ring at the back does not support a transport with legs still attached. The clearance between the rocket body and the transport ring seems too small. It doesnt look like this should be a big problem but maybe there are aspects that are more complicated than just changing the metal ring.
Quote from: Semmel on 09/15/2018 07:24 pmFrom the images shown in this post of the recent returned B5 booster:Quote from: cygnusx112 on 09/15/2018 07:06 pmThe booster moving on 401.It seems the transporter ring at the back does not support a transport with legs still attached. The clearance between the rocket body and the transport ring seems too small. It doesnt look like this should be a big problem but maybe there are aspects that are more complicated than just changing the metal ring.This has been discussed before and the consensus always has been that there is clearance. The ring is outward from the body at that point. Did you see those prior discussions? what do you think is flawed in their analysis? or are B5 legs bigger?
If you zoom in, this is a great closeup of a Block 5 engine section. Source: https://imgur.com/gallery/ASbfdA5#QNCfKaG - It really is in MUCH better shape than previous cores. - the flexible engine skirt material seems to have changes, look like fabric before but now it is different.
Quote from: Lars-J on 09/18/2018 12:27 amIf you zoom in, this is a great closeup of a Block 5 engine section. Source: https://imgur.com/gallery/ASbfdA5#QNCfKaG - It really is in MUCH better shape than previous cores. - the flexible engine skirt material seems to have changes, look like fabric before but now it is different.I wonder if they are heatshield plates made from the same or similar material as the base of the f9, you can see on the opening for the two nearest engines that they are fixed to the engine and the move with it (top left you can see a gap then the closest the plate overhangs the opening), i suspect those fabric boots still exist but behind this new plate which prevents most of the prolonged reentry gas on the fabric.
Northrop Grumman installs the OmegA first stage aft skirt in preparation for a full-scale static test in Promotory Utah.
IIRC an element of Block 5 is the device atop the Falcon first stage that pushes against the Vacuum Merlin engine to assure clean stage separation. I don't recall seeing any mechanical subsystem like that on other rockets. (Please post something if you know of it.)Page 15 of May 20 SpaceNews has a photo with the caption QuoteNorthrop Grumman installs the OmegA first stage aft skirt in preparation for a full-scale static test in Promotory Utah.In the "first stage aft skirt" are three mechanical subsystems.They look a lot like the Falcon stage separation pusher.So not only is the Air Force allowing NG to compete against SpaceX for launches with their still undeveloped rocket, and giving NG money to develop that competitor to SpaceX's Falcon, but NG is in turn copying some of SpaceX's innovations.Albeit in an expendable systemAt the very least this is ironic.
Quote from: Comga on 05/29/2019 08:40 pmIIRC an element of Block 5 is the device atop the Falcon first stage that pushes against the Vacuum Merlin engine to assure clean stage separation. I don't recall seeing any mechanical subsystem like that on other rockets. (Please post something if you know of it.)Page 15 of May 20 SpaceNews has a photo with the caption QuoteNorthrop Grumman installs the OmegA first stage aft skirt in preparation for a full-scale static test in Promotory Utah.In the "first stage aft skirt" are three mechanical subsystems.They look a lot like the Falcon stage separation pusher.So not only is the Air Force allowing NG to compete against SpaceX for launches with their still undeveloped rocket, and giving NG money to develop that competitor to SpaceX's Falcon, but NG is in turn copying some of SpaceX's innovations.Albeit in an expendable systemAt the very least this is ironic.Can you post a picture of the Falcon 9 separation system? The picture you refer to doesn't look like the tripod that's on the Falcon 9.
Quote from: Comga on 05/29/2019 08:40 pmIIRC an element of Block 5 is the device atop the Falcon first stage that pushes against the Vacuum Merlin engine to assure clean stage separation. I don't recall seeing any mechanical subsystem like that on other rockets. (Please post something if you know of it.)Page 15 of May 20 SpaceNews has a photo with the caption QuoteNorthrop Grumman installs the OmegA first stage aft skirt in preparation for a full-scale static test in Promotory Utah.In the "first stage aft skirt" are three mechanical subsystems.They look a lot like the Falcon stage separation pusher.So not only is the Air Force allowing NG to compete against SpaceX for launches with their still undeveloped rocket, and giving NG money to develop that competitor to SpaceX's Falcon, but NG is in turn copying some of SpaceX's innovations.Albeit in an expendable systemAt the very least this is ironic.Those look like hydraulic TVC actuators, not for stage separation. And Falcon 9 is the not the first rocket to use pneumatic actuators for stage separation (Delta IV is one example). However, F9 may be the first to use a center actuator that pushes on the second stage engine bell.
Pneumatic actuators have extensive spaceflight experience, most notably on the Delta launch vehicle stage separation system. Pneumatic actuators possess larger specific force capability (N/kg) than mechanical springs, giving 4 to 5 times the kickoff force of springs of the same mass.
