• Cosmic Entry

IFT1, Repairs and IFT2 Previews

On April 20, 2023, SpaceX launched the world's largest rocket and it became a record-setting day. People on the outside may have looked at the launch itself including the powerslide off the pad as well as the triggering of the automatic flight termination system as a failure. SpaceX headquarters in Hawthorne, California applauded massively when the flight ended after multiple flips and tumbles in spectacular fashion. Once the dirt, dust, and debris cleared the air, what was left surprised some, and the doomsayers responded with SpaceX will never fly again, SpaceX will not fly for years! Once we see rebar showing under the orbital launch mount the realization is that there will be a multiple month-long delay to get the system ready for the second launch of the superheavy/starship prototype. Following the first launch. the road remained closed for three days while teams from SpaceX assessed the damage to stage zero and the infrastructure at the launch mount. youtube.com/LabPadre Getty Images: Patrick T. Fallon, Contributor Some of the opportunities that SpaceX had to improve their pad infrastructure was due to the Fondag concrete disintegrating due to the exhaust of 27-31 raptors igniting at T-0. Very soon after the launch, it became clear the magnitude of the damage to the pad was significant. In an X space very soon after the launch, Elon Musk said for launch 2 there would be a steel water-cooled plate that was not ready in time for IFT-1 and SpaceX thought that due to the result of the 33-engine static fire that it would hold up to launch of a fully fueled starship and superheavy booster. With every crisis comes an opportunity to improve on a design or in this case to improve the structure to stand up to the load of 33 raptor engines for up to six seconds prior to spooling up all 33 engines to full power. When looking at the video of IFT 1, it took six to eight seconds for the full stack to lift off. According to SpaceX, the concrete began to degrade at T+3 seconds and this will be addressed in IFT2. To help support the pad for the second flight of the starship system, SpaceX drilled vertical supports, put in supports then filled them with concrete. This many supports will give the pad more structural support in the event that a second pad failure would not throw chunks of concrete and debris as high as the full stack and into the Gulf of Mexico. The second and more robust improvement was the addition of the water-cooled steel sandwich plate i.e. water bidet system, this system has water tanks gas tanks to force the water through small holes to divert the force of the exhaust and more importantly, much of the water will be flashed to steam to help with acoustic reverberations on the booster and the ground support equipment. The steel plate has been used twice with a partial capacity with the static fires on August 6th and 25th as well as a test on July 28th and August 19th, and then on August 10th, a third water tank showed up at Starbase, but was not ready for the August 25th static fire. On October 24th during the closure for the wet dress rehearsal, there was a full-volume deluge test after a large amount of detanking had been accomplished. The hope for SpaceX is that this will mitigate all of the destruction of the pad during the second flight of Starship. The argument can be made that the full-scale test that was significantly delayed from the WDR countdown was for Fish and Wildlife to be able to see how much water is released and also how it is collected and where water intrusion ends up. Image Credit: SpaceX Another physical modification to the booster itself is the changing of the chines to all being the same size which now house CO2 tanks to help with engine bay fires as well as an all-electric thrust vector control system which will help because there will be no need for hydraulic power units on the booster. On the first launch, there were multiple problems but two that caused significant issues were engine bay fires that severed communication cables and rendered the thrust vector control system inoperable and then eventually caused the hydraulic power units to fail. Then the flips, turns, and twists of the full stack until flight termination finally did its job. Once the first flight got close to stage separation, there was supposed to be an arc back to allow separation of the ship and booster which never happened due to being down at least 6 engines so every milestone was delayed and by the time it got to staging there was no way that maneuver could be accomplished. Enter a hot staging ring! So this ring is developed to shield the booster and allow the ship engines to fire and get away from the booster. How this all works is yet to be seen and we will all watch in excitement as we hope the booster is not harmed once at least three of the raptors ignite on the ship. Image Credit: SpaceX Outside of physical upgrades and structural repairs to the launch mount there have been procedural updates to how SpaceX is starting up the engines on the second flight will be modified, the goal according to SpaceX is to get all 33 engines to full power by T+0:00:03.00. In their analysis they said the pad failure began T plus 4 through 6 or 7. To get this procedure corrected and perfected they have worked on different start-up procedures including engine venting through the skirt of the booster and spinning up the outer 20 engines using the launch mount. After the first static fire, which only lasted 2.74 seconds out of a planned 5 seconds and only 29 or 30 of the engines fired for the 2.74 seconds there was repeated testing of the launch mount without booster 9 there testing the startup procedures. The second static fire was more successful with 31 out of the 33 firing for full duration with the water deluge plate active. So this brings us to what are the expectations of Starship flight 2. Elon Musk speaking to the IAC in Azerbaijan said if the “engines light and the ship doesn’t blow up there is a decent chance of reaching orbit”. Expectations are still tempered which most reasonable people would probably say staging is a reasonable goal. From what has been released and gathered it seems the trajectory of flight two is the same profile as flight one. Exclusion zones at the time of writing this article had been posted for the Gulf of Mexico to just south of Key West, it has not been posted yet for Hawaii where the ship should re-enter on a ballistic suborbital trajectory on an unpowered splash down. The booster, if everything goes properly, will do a boost back burn and will do a soft landing 100-200 kilometers off the coast of Texas where it will sink or be scuttled at sea. Images Credit: FAA/SpaceX As the space community gets excited about the second flight and looks at flights, hotel reservations, and rental cars, space fans might want to pump the brakes on what needs to happen before a launch can be scheduled. First and most importantly need a sign-off from the Fish and Wildlife Service on the deluge plate, then a launch license from the FAA which SpaceX seems to think is imminent. So what markers are we looking for beyond the announcement of the launch license? There will be notices to mariners and pilots closing airspace. Right now have a notice to mariners in the Gulf of Mexico NET November 6, 2023, but no Hawaii notice as of yet. Also, NASA’s WB57 will be scheduled to do high-altitude imaging of the launch because of NASA’s vested interest in the Starship program for the Human Landing System. As of this writing, there was a placeholder for November 3-10th, 2023. While this is always subject to change, those are the only concrete things we have right now. Other markers will be an evacuation notice of 5 miles around the pad, temporary flight restrictions up to space, not to be confused with the standing Temporary flight restriction up to 10,000 feet, and Hawaii and Gulf of Mexico exclusion zones. Sometimes it's like reading tea leaves. Every step gets SpaceX closer to launch and with it, the excitement builds in the residents of Boca Chica, Port Isabel, and Brownsville but also the guests that will descend on the area. A statement of caution, be careful not to see the FCC approval to communicate with starships during launch. That is not launch-specific and is just renewed periodically. How is success or failure determined? The argument can be made that success will be hot staging, and soft landing of booster in the Gulf of Mexico while a stretch goal might be the ship correctly getting onto a suborbital ballistic trajectory with an unpowered splashdown with Ship 25 intact. If this stretch goal can be achieved it will then avoid the need for an FAA incident report and investigation. Until then, we can all know one thing…. excitement is guaranteed!! Joel Reinking is a professor of Political Science at Florida Southwestern State College and a self-proclaimed space nerd, writer, and photographer his research interests include public-private partnerships in the aerospace industry and researching efficacy in government.

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