B7.1

This article is about Test Tank B7.1. For Booster 7 (B7), see Booster 7 (B7).

B7.1 was a booster test tank. It was tested extensively at the launch site on the structural test stand with the cap. First parts were spotted on 22 March 2022.

Booster test tank B7.1 used a revised thrust puck design, which was later used on Booster 9. It was thrust ram tested in order to verify the design, thus B9 wouldn't need additional testing.

## 16 June 2022 - Roll out

Timeline according to LabPadre discord:

* 20:23 B7.1 exited high bay
* 21:22 Entered hwy 4
* 22:35 Arrived at launch site

## 28 June 2022 - Cryo proof testing #1

Timeline according to LabPadre discord:

* 11:37 Road closed
* 13:59 Pad cleared
* 14:43 OLS tank farm venting
* 14:45 Venting on B7
* 15:25 Cars to pad
* 15:44 Pad cleared again
* 17:02 Frost line started to form
* 17:57 B7.1 fully loaded with LN2
* 22:55 Road opened

## 19 July 2022 - Cryo proof testing #2

Timeline according to LabPadre discord:

* 09:36 PA: "Attention to the pad, Orbital pad clear at 9:45"
* 09:51 Road closed
* 10:52 Pad cleared
* 14:19 OLS tank farm venting started on LOX side
* 16:01 Cars to pad
* 16:30 Pad cleared again
* 16:58 Frost forming
* 18:23 Fully frosted and filled with LN2
* 20:03 Detanking started
* 21:23 Road opened

## 21 July 2022 - Cryo proof testing #3 and S24 spin prime

Timeline according to LabPadre discord:

* 10:01 Road closed
* 10:18 PA: "Attention on the pad, all personnel should leave the launch site"
* 10:43 Pad cleared
* 11:12 OLS tank farm LOX side active
* 12:10 B7.1 frost appeared
* 13:07 B7.1 fully frosted, filled with LN2
* 13:53 QD arm tested
* 14:21 SoLS tank farm venting
* 14:55:?? Engine chill, frost forming on LOX tank
* 15:09:32 S24 Spin prime test #4, likely only with one enginee
* 15:31:14 Spin prime test #5, likely two engines
* 15:35 S24 Depress vent
* 16:13 S24 detanking, Depress vent
* 16:59:32 Load ban heard at B7.1 crush testing, ice fell of, visible buckling on external stiffeners appeared
* 18:30 B7.1 detanking started
* 19:55 OLM venting started
* 20:28 Road opened

## 27 July 2022 - Cryo proof testing #4

Timeline according to LabPadre discord:

* 10:00 Road closed
* 10:12 PA: "Attention on the Pad, Clearing Orbital and Suborbital Pad in 30 minutes"
* 12:24 Pad cleared
* 12:31 OLS tank farm LOX side venting started
* 13:05 Venting from top vent
* 13:20 Frost started to form
* 14:24 Full frost reached
* 14:36 Vents valves closed
* 16:17 Frost receding, detanking
* 16:33 Depress
* 17:58 Repressed, test continued
* 18:14 Frost receding, top vent stopped venting

## 29 July 2022 - Roll back

Timeline according to LabPadre discord:

* 08:45 Vent stack removed from top
* 09:11 LR11000X picked up load spreader
* 09:25 B7.1 attached to LR11000X
* 11:18 Lifted by LR11000X
* 11:35 Touched down on transport stand
* 14:15 LR11000X detached from B7.1
* 14:32 Started to move
* 14:43 Entered hwy 4
* 15:29 Arrived at build site

## 01 September 2022 - Cryo proof testing #4

On 01 September 2022 SpaceX continued testing test tank B7.1 after it reconfigurations and work at the production site and roll back on 25 August 2022.

It was speculated that S24 could do a static fire as well as a Overpressure notice was issued, but only its forward flaps were tested. Timeline according to LabPadre discord:

* 08:38 Road closed
* 09:56 Pad cleared
* 10:44 Venting on B7.1 and frost forming
* 12:36 Top vent valve closed
* 12:46 Pistons on can crusher were pulling down
* 13:49 Main vent valve reopened
* Road closure extended until 10 pm
* 20:34 Road opened

The testing was photographed on a flyover by RGV:

## 06 September 2022 - Cryo proof testing #5

Timeline according to LabPadre discord:

* 10:03 Road closed
* 12:42 Pad cleared
* 13:43 Cryo load and venting
* 15:25 Top vent turned off
* ?? Cars to pad

## 09 September 2022 - Lifting

Timeline according to LabPadre discord:

* 02:39 LR11000X attached to structural test stand cap
* 06:12-21 Can crusher cap lifted off B7.1 by LR11000X
* 08:24 Can crusher cap entered hwy 4
* 10:11 Structural test stand "can crusher" top/cap arrived at production site
* 14:03 Lifted off structural test stand
* 15:12 LR11000X unhooked from B7.1

1. ↑ https://twitter.com/RingWatchers/status/1606763376029405185
2. ↑ https://twitter.com/RGVaerialphotos/status/1565400306480971778