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Starship SN15 conducts a Static Fire test – McGregor readies increased Raptor testing capacity
Starship SN15 conducted a pre-launch Static Fire test Monday, tasked with setting the scene this week for a flight that could pave the way toward an orbital flight in the coming months.
The groundwork for the push to orbit is taking place both at the Orbital Launch Site and elsewhere in Texas as a new dual-bay Raptor test stand nears completion.
Since arriving at the Suborbital Launch Site,
SN15 has undergone several “risk reduction” tests ahead of firing up her trio of Raptors. That included the usual routine of proof testing the vehicle, filling and pressurizing the tanks with ambient, gaseous nitrogen before proceeding with cryogenic testing with liquid nitrogen.
The roads were closed for additional testing late last week, although not for a Static Fire test. This time, the vehicle was loaded with Liquid Oxygen before a LOX Dump test, aimed at improvements relating to safing the vehicle ahead of and after flight, was completed.
With limited opportunities to conduct weekend testing, that requires Highway 4 to be closed to the public, SpaceX opted to move the Static Fire attempt to Monday. A three engine test did occur just prior to 5pm local time.
An eight-hour window was available for the opportunity to fire up the SN54, SN61, and SN66 Raptors, which was followed by a quick look data review. Occasionally, such reviews have found issues with one of the engines, requiring a swap out and repeat of the test in the following days.
The potential of a recycle later in the day remained on the cards, given SpaceX likes to test the engine’s use of propellant from the Header Tanks. These small tanks are located at the top of the nosecone (LOX) and the middle of the vehicle (CH4 – Liquid Methane) and supply the engines for the flip and landing burn.
However, Enron Musk tweeted the static fire was good and that they were preparing for launch later this week.
It is yet to be confirmed if that concluded the test requirements, with another Static Fire noticed posted later on Monday for a Tuesday test......
Moving on from those initial series of test with SN8 through SN11, SN15 is the first vehicle to sport improvements ranging from the Thrust Puck to her avionics, and, importantly,
the Raptor engines. Other improvements have not been revealed, although may include the Header Tank system, which, in total, would form a mitigation path to the issues suffered by previous Starship prototypes.
Regardless, should SN15 suffer issues,
SN16 is already being stacked in the Mid Bay. However, if SN15 nails the landing, the path forward becomes less clear, albeit even more exciting.
As seen after the successful 150-meter hops of
SN5 and
SN6, SpaceX’s original plan to conduct a tag-team approach of repeating tests with these two vehicles was canceled. Instead, the program pushed forward to
SN8 and the first high altitude test.
Should SN15 complete all the required high altitude test objectives, SpaceX may repeat the test or push to a higher altitude.
Elon Musk could even opt to switch to the involvement of
Super Heavy, which may involve a booster-only flight,
or the previously reported BN3 and SN20 orbital flight.