[ad_1]
Over the past week, SpaceX’s South Texas Starship plant appears to have shifted into high gear and is now assembling the first prototype orbital-class Super Heavy booster at a breakneck pace.
While the assembly of the Super Heavy known as Booster 4 (B4) was not much different from what CEO Elon Musk described as a “very difficult” version of Booster 3 until last week, work on the rocket has visibly accelerated. As of January 2020, the process of building Starships and Super Heavy boosters has been fairly straightforward. On and off site, raw materials (mostly steel sheets) are cut, folded and welded into relatively small pieces which then travel to (or around) Boca Chica by truck, forklift or crane.
Using jigs and a fair amount of automation, the resulting material is then welded to form domes, collecting tanks, transfer tubes, tank drums, shutters, etc. Once the sub-assembly is complete, these integrated rocket sections are reinforced with spars, ribs and baffles and fitted with mechanisms, anchor points, brackets, plumbing, etc. Finally, the final assembly – better known as stacking and by far the most visible step – can begin and technicians stack each of these prefabricated segments on top of each other to form a complete Starship or Super Heavy. .
While making parts and integrating subassemblies alone takes weeks or months, these first steps can be done more or less simultaneously, meaning SpaceX can prepare sections for several different ships and boosters. at the same time. Over the past six months or so, at one point, SpaceX has had over 40 to 60 rings in operation as part of over 15 to 20 different “sections” of rings visible throughout Starbase.
Respectively, each Starship and Super Heavy thruster requires 20 and 36 rings each, while each of the propellant storage tanks that SpaceX is building for the rocket’s first orbital launch pad requires 12-15. All told, SpaceX typically has a combination of around 3-5 GSE ships, boosters, and tanks at some stage of assembly. Unsurprisingly, some assemblies are more difficult than others, and building the first in a series of prototypes almost invariably took significantly longer than the later average that develops.
| Booster 3 | Booster 4 | |
| Starting the LOx tank | May 20 | July 16 |
| LOx tank finish | June 18 | July 31 ? |
| Starting the CH4 tank | June 24 | July 28 |
| CH4 tank finish | June 27 | July 29 |
| Final pile | June 29 | 1st of August ? |
In this sense, it is not a huge surprise that SpaceX’s Booster 4 assembly quickly exceeded the pace set with Booster 3 less than a month earlier. SpaceX began stacking Super Heavy B3s around May 20, starting with the rocket’s rear liquid oxygen (LOx) tank. Five separate stacks are needed to turn the 23 steel rings of the LOx tank into a single structure – a process that took SpaceX about a month with Booster 3.
The assembly of the methane tank (CH4) Booster 3 started a few days ago after the completion of the LOx tank but proceeded much faster, ending a few days later. Two days later, these two tank sections were then mated and welded together to complete the ~ 65 m (~ 210 ft) high cell of the Booster 3.
Now, just four weeks after Booster 3 was deployed to the launch pad for stress and static fire testing, Super Heavy Booster 4 is on track to reach its full height of ~ 65m almost twice as fast. As the work started around July 16, only one (extremely complex) engine section is missing from the B4 oxygen tank and the booster’s methane tank has been stacked until the end – 13 rings high – in less than two days. This leaves SpaceX’s first potentially airworthy orbital-class Super Heavy booster just two stacks from completion within two weeks of starting assembly.
If SpaceX can keep that pace for a few more days, the Booster 4 assembly will be the fastest of any full-height prototypes ever built at Starbase, most of which are Starship prototypes that are about half to about three-quarters in size. the size of the Super Heavy.
[ad_2]
Source link