Featured Image Source: @SpacePadreIsle via Twitter.
SpaceX teams in South Texas are getting ready to conduct the next phase of testing for the Starship SN3 prototype this week. The rocket company is in the process of developing a production line of stainless-steel flight vehicles to conduct a variety of tests. Starship SN3 is the third prototype this year, that will undergo a series of pressure tests in the coming days. Starship SN3 has been transported to the launch pad in Boca Chica Beach, Texas, where its undergoing preparations ahead of a potential debut flight. The Cameron County Texas website announced a series of Highway 4 road closures at Boca Chica which usually indicates SpaceX is going to conduct vital work. A road closure is scheduled for today, April 1st, at 4:00 p.m. to 5:00 p.m. and 8:00 p.m. to 9:00 p.m. CST. local time. Additional road closures are scheduled for April 6 to April 8 from 9:00 a.m to 11:59 p.m. CST every day.
Pressure tests on SN3 will occur later this evening. Road closure time is only indicative of intention to test. #SpaceX #Starship #BocaChica— SPadre (@SpacePadreIsle) April 1, 2020
Visibility should be very good tonite, watch live on SPadre
🎥🚀 4K Starship Cam
The first series of tests are expected to be pressure tests that may be conducted as soon as today. Pressurization tests are conducted to assess Starship's stainless-steel structure and weld strength. According to an email exchange between SpaceX and city officials the road closure today at 4 p.m. will be for "An initial proof test using room temperature nitrogen." If successful, SpaceX will then conduct a cryogenic liquid nitrogen test at 8 p.m. tonight. A cryogenic pressure test will determine if the vehicle is ready to take flight. Previous Starship prototypes were destroyed this year during pressurization tests. The vehicle must withstand a pressure test between 6 and ~8.5 bar in order to be approved for flight.
Big day for Starship SN3! SpaceX is expected to perform a room temperature nitrogen proof test followed by a cryogenic nitrogen proof test.— Michael Baylor (@nextspaceflight) April 1, 2020
Per an email exchange with the county, testing is scheduled to begin at 4 pm CDT, but these schedules are fluid.https://t.co/WFa2LMHorv pic.twitter.com/3ocVXzYmPT
According to a Federal Aviation Administration NOTAM notice, SpaceX has plans to launch Starship SN3 sometime around April 6 to April 9 -that's if the vehicle passes the pressure test. If pre-flight preparations go smoothly, SpaceX engineers will integrate Raptor engines on Starship SN3 and perform a static-fire test to conduct a test flight. It will be the first time a fully-assembled Starship vehicle takes flight. The first launch is expected to be at an altitude of approximately 150 meters above Boca Chica Beach.
The company has only conducted one flight with a scaled-down version of Starship known as Starhopper. Starhopper launched 150 meters and successfully landed with the power of its own engine in 2019. SpaceX will also attempt to land SN3 on a nearby landing pad, but the SN3 vehicle features many changes that will be tested for the first time in flight. Some of those changes are retractable landing legs and aerodynamic fins. Though, its unclear if engineers plan to test out SN3 fins on the first short test because the test will be conducted at a relatively low altitude.
Elon Musk, founder and chief engineer at SpaceX, shared a photograph showcasing the bottom of Starship SN3 which features gear for 6 landing legs.
"The legs extend & telescope out, so are longer than they seem, but not as long as they will be for SN4+."
Musk explained via Twitter. Starship SN4 will be the next prototype to be tested which will feature longer landing legs. SN4 is expected to conduct a higher-altitude test flight of about 20 kilometers to test out the fins and the power of Raptor engines. The next prototype is actively under construction. SpaceX aims to start a Starship production factory to test out many vehicles, each featuring improvements. A high iteration rate speeds up the craft's development.
A 3D-artist made an animation of how Starship's landing legs will deploy -shown below. He asked Musk via Twitter, if his animation was an accurate rendition of how Starship's landing legs will deploy upon landing, to which he responded:
"Yes, v [very] close! Nice work. Those are V0.9 legs, so major upgrades coming. Need wider span, longer stroke & ability to auto-level for uneven ground or leaning into high winds."
Yes, v close! Nice work. Those are V0.9 legs, so major upgrades coming. Need wider span, longer stroke & ability to auto-level for uneven ground or leaning into high winds.— Elon Musk (@elonmusk) April 1, 2020
The weeks ahead will be exciting if the pressure test is a success! Good luck to SpaceX!