The first entirely private sector mission to the International Space Station (ISS) lifted-off from the SpaceX Falcon launch facilities at Pad 39A, Kennedy Space Centre (KSC) on Friday April 8th, 2022, carrying a crew of four to the station aboard the Crew Dragon vehicle Endeavour.
The launch took place at 16:17 UTC, with the Falcon 9’s first stage making a flawless ascent prior to upper stage separation, then completing a boost-back manoeuvre and a successful return to Earth to land on one of the SpaceX autonomous drone ships. It marked the 5th successful flight for the core stage, which coincidentally was the same stage that launched the first all-private mission to Earth orbit – Inspiration4 (see: Space Sunday: Inspiration4 and Chinese flights) in September 2021.
Ax-1 has been seen by some as just another jolly jaunt into space by those who can afford it; however and in fairness, it is slightly more than that. Axiom Space was founded to create the world’s first commercial space station. While others have since entered this arena, Axiom has been granted access to the forward port of the ISS’ Harmony module, to which Axiom plans to dock the Axiom Orbital Segment; a complex that could grow to five pressurised modules after 2024.
In order to help finance their plans, Axiom plan to offer a series of fare-paying flights to the ISS, with the 8-10 day Ax-1 being the first. However as a part of these flights, those paying for seats will also help Axiom pave the way towards their goal in bringing their first module to the ISS in 2024 and carry out a suite of selected on-orbit studies and experiments.
Commanding the mission is Michael López-Alegría, who was one of NASA’s most experienced astronauts prior to retiring in 2012. He holds the US record for the most EVAs undertaken by a NASA astronaut (10 totalling 67 hours and 40 minutes) and is also (and quite separately) licensed to officiate at wedding ceremonies. In 2017, he joined Axiom Space as their director of Business Development, and allowing him to regain his space flight status. Joining him on the mission are US entrepreneur Larry Connor, Israeli businessman and former fighter pilot Eytan Stibbe and Canadian philanthropist and businessman Mark Pathy, each of whom paid an estimated US $55 million to join the mission.
Endeavour took a gentle path up to the space station over a 20 hour flight; however, docking was delayed by some 45 minutes due to an issue with the video system used by the ISS crew to monitor docking operations.
Following post-docking checks, the hatches between Endeavour and the ISS were opened, and the Ax-1 team were welcomed aboard the station by the 7-person crew. During a brief ceremony-come-video press briefing, López-Alegría – who had become the first former astronaut to return to the ISS – presented his three fellow crew members with astronaut pins. Whilst not official US astronaut pins, those presented to Stibbe, Connors and Pathy have been designed by the Association of Space Explorers, which encompasses a lot of members from 38 different countries that have flown astronauts.
Alongside of their work in support of Axiom Space, the Ax-1 crew will take part in a multi-discipline science programme of some 25 different research experiments sponsored by the ISS U.S. National Laboratory in collaboration with the Mayo Clinic, the Cleveland Clinic, Canadian Space Agency, Montreal Children’s Hospital, Ramon Foundation (named for Ilan Ramon, the Israeli astronaut killed in the Space Shuttle Columbia disaster of 2003) and Israel Space Agency.
As a fully private mission to the ISS, Ax-1 not only features a non-government crew launched aboard a private sector space vehicle and rocket, it is also being managed through the SpaceX flight control centre, Hawthorne, California and Axiom’s own mission control centre in Houston, Texas.
Artemis WDR: Further Issues and Delay
The Wet Dress Rehearsal for the Artemis 1 Space Launch System (SLS) vehicle at KSC’s Pad 39B continues to hit niggling problems, with a resumption of testing now pushed back until April 12th.
As I noted in my previous Space Sunday report, while it had been hoped this full test of a launch countdown procedure, including fuelling the massive rocket’s liquid propellant tanks, could be completed in a 3-day period between April 1st and April 3rd, the test ran into a series of issues that caused efforts to be scrubbed on two occasions.
The issues were now with the rocket itself, which performed flawless during the tests up until the scrubs were each called, but with support systems within the vehicle’s mobile launch tower. However, after the second set of issues on April 3rd caused a scrub, the plan had been to investigate and correct the issue in time to resume the countdown on April 4th and complete the tests ahead of the launch of the SpaceX / Axiom Ax-1 mission reported above – a launch that had already been postponed from April 3rd.
As the investigations took longer than planned, on April 4th, the decision was taken to stand down WDR operations to allow the Ax-1 to go ahead, and to resume the tests on April 9th. But on April 7th, during a check on the rocket’s systems, engineers found a problem when trying to maintain helium purge pressure in the Interim Cryogenic Propulsion Stage (ICPS), the upper stage of the rocket itself.
The ICPS is based on the second stage of the Delta 4 launch vehicle. It uses a single RL10 engine to propelled the payload carrying section of the rocket – although it will be replaced by the more powerful and purpose-built Exploration Upper Stage from the third SLS flight (Artemis 4) onwards. This particular ICPS was one of the first to be completed, and had been in storage for several years awaiting the completion of the Artemis 1 core stage and boosters.
The issue was traced to a check valve intended to prevent helium – used to purge propellant lines and drain propellant – from escaping the rocket., the valve failing to function as intended. To allow time for a possible fix for the problem to be developed and attempted, the decision was taken to push test resumption by to April 12th. Unfortunately, by April 9th, it became clear that the valve would need to be replaced; but rather than cancel the WDR completely, NASA has decided to complete the test as planned on the 12th – but to only perform a “minimum fill” of the ICPS tanks; enough to prove the propellant loading system works. This, with a full load of the core stage tanks is seen as sufficient for the WDR to be completed.
Replacing the check valve will be carried out once the rocket has been returned to KSC’s Vehicle Assembly Building as a part of the post-WDR checks. However, this means that any chance of Artemis 1 making the hoped-for May launch window is now out of the question, whilst NASA is confident replacing the valve will correct the issue, it is also unlikely the turn-around can be completed in time for the rocket to make the June 6th through 16th launch window, potentially making July the earliest Artemis 1 launch opportunity.