SpaceX Sets Launch Date for Starship Integrated Flight Test

SpaceX has updated the official Starship webpage to include the timeline for Starships Integrated Flight Test. A SpaceX tweet, which can be found here, stated that the launch is targeted for "next week", and a now deleted official livestream page stated April 17th as the targeted date. The livestream will begin 45 minutes before liftoff. SpaceX has also confirmed that Booster 7 will attempt a water landing in the Gulf of Mexico, and that Ship 24 will not perform a powered descent, only the bellyflop manuever.

Days Leading Up to OFT

While SpaceX is yet to receive the launch license for the Starship-Super Heavy vehicle, launch teams are still targeting April 17th, 2023 as the first attempt for liftoff for the rocket. SpaceX have a plethora of planned backup dates (can always get more), with dates April 18th to April 22nd available for backup as stated on the most recent FAA Advisory. Currently, only dates April 17th -> 19th have possible road closures on the Cameron County website, but getting more closures will not be difficult. If the vehicles complete fueling before a scrub is called, it will likely take three days to replenish the necessary propellant for a second attempt.

There is still work to be done around the launch site that still remains to be completed. This includes but is not limited to: clearing out the launch site, water spraying launch site, painting the Orbital Launch Mount, fitting Ship 24 with flight termination hardware, and posting evacuation and overpressure (OP) notices. These steps are likely to be seen within the next couple of days leading up to April 17th.

Countdown to Launch

In the webpage update, SpaceX has posted the countdown sequence and major events leading up to flight. 

• T-99 minutes: Booster Liquid Methane and Liquid Oxygen Load Begins

• T-82 minutes: Ship Liquid Methane Load Begins

• T-77 minutes: Ship Liquid Oxygen Load begins

• T-45 minutes: SpaceX livestream goes live

• T-16 minutes: Raptor Engine Chill on Booster begins

• T-8 seconds: Booster Ignition Sequence begins

• T-0 seconds: Liftoff (Excitement Guaranteed)

Liftoff to Landing

After liftoff, Starship will begin its hour and a half journey to space and back. All 33 booster engines will power the rocket during its first phase of flight. At T+55 seconds, the rocket will experience Max-Q, the period of highest pressure on the rocket. This is caused by the resistive force of air with the increasing thrust of the vehicle as it marches to orbit. Reaching Max-Q is a major structural milestone for all rockets and is a common point of failure for many inaugural launches. The booster will continue to push the upper stage towards orbit until T+3 minutes, when the vehicles will separate. Following this, the booster will reorient in preparation for landing. The Starship upper stage will ignite its six raptor engines five seconds after separation. The upper stage will continue on to the final partial orbit for the rocket. The booster will continue down to earth, following a similar trajectory to that of the Falcon 9 booster on RTLS launches. The booster will be attempting to land just east of the launch site in the Gulf of Mexico at T+8 minutes.

At T+9 minutes, the second stage engines will turn off, having reached orbital velocity. The Starship upper stage will intentionally stop short of a true low earth orbit, allowing the stage to reenter naturally without needing to perform a reentry burn. The upper stage will then perform its reentry and landing sequence starting at T+1 hour 15 minutes, targeting just north of the Hawaiian islands as the anticipated landing area. The upper stage will perform a “bellyflop” aero-manuever seen in the Starship prototype test flights, in which the upper stage reenters on its leeward side to induce high drag while falling through the atmosphere, slowing it down. However, Ship 24 will not perform a powered landing, commonly referred to as the "Flip Manuever" that we've seen in previous suborbital flight tests (SN8-SN15, some successful, some not). The upper stage will splashdown in the Pacific ocean after 90 minutes of flight, nearly completing one orbit around earth.

This is the proposed flight plan for the inaugural launch, but there is a high likelihood of technical issues to appear on this flight. Depending on the severity of the issue and the phase of flight, there are multiple different approaches that SpaceX will be able to take. If at any time the vehicle poses a threat to either endangered or harm the public, the ship and booster are fitted with a flight termination system that will be able to safely abort the vehicle during the course of its flight. This safety precaution is present on all US-based rockets, including Starship.