This night, NASA held a media occasion to supply an replace on the newest developments for an Artemis 1 launch try on November 16. Jeremy Parson, EGS Program deputy supervisor, and Mike Sarafin, Artemis 1 mission supervisor introduced an image of a launch automobile that is able to finish the 50 12 months hiatus of NASA exploring past low-Earth orbit.
Jeremy Parson started the press briefing by noting that the launch staff was on consoles at 1:24 AM EDT, Nov. 14. He additionally mentioned that every little thing going effectively and that the launch countdown is on schedule.
Mike Sarafin adopted Parson within the briefing. He famous that there was a launch -1 day MMT assembly that lasted for 1 ½ hours and was main centered on two particular points attributable to Nicole. The LH2 electrical connection cable and the climate striping on Orion spacecraft.
Parson started his a part of the briefing by gaving an replace of what has occurred because the Artemis 1 mission administration staff’s, or MMT’s, convention on the night of Nov. 13.
On Nov. 13, the Artemis 1 automobile was powered-up and a sequence of program particular engineering exams, or PSET’s, which is mainly built-in automobile testing. An intensive check-out of the automobile was accomplished and every little thing is wanting good. On the cell launch platform (MLP), crews are getting panels and valves all prepared for cryo loading. The sound suppression and ignition over-pressure tank stuffed with water. And energy was brought-up on Orion, ICPS, and Core Stage and they’ll stay powered by way of launch countdown.
Going ahead with what to anticipate tonight and tomorrow, starting with Monday night time. Crews will start to cost all of the flight batteries on the automobile. Pressurizing the Core Stage composite over-wrap strain vessels shall be accomplished. There shall be ultimate walk-downs Monday night time and into Tuesday morning. The launch staff will conduct a sequence of comm. check-out’s with Orion.
For tomorrow, the schedule picks up:
12:04 PM EST, Decide-up with blast hazard space clear.
1:14 PM, Air to GN2 switch-over.
2:04 PM, Clear-out launch hazard space for all personnel.
2:24 PM (T-6:40), New built-in maintain.
3:24 PM, Launch Director offers a go, no-go for cryo loading.
The brand new built-in maintain is similar built-in maintain that beforehand lasted 2:30 however with an hour added in for cryo loading idea of operations modifications. That is the “Kinder Gentler Cryo Loading” idea that NASA’s cryo loading staff adopted from that utilized by the Stennis people in fueling-up the SLS Core Stage for its Inexperienced Run. An hour was added to do a slower, extra mild loading of cryo, starting with 17-20 min for LH2 chill-down and adopted by 32 minutes for fast-fill. Parson additionally mentioned that LOX and LH2 loading now being achieved in parallel.
The launch window, or T 0, is at 1:04 AM Nov. 16, Wednesday and there’s a 2-hour launch window.
Turning to the 2 points on the Artemis 1 automobile as a result of Hurricane Nicole, in the course of the storm alerts going by way of {the electrical} cable on the MLP tail service mast liquid hydrogen umbilical began having transient, or transient, points.
At a top-level, what the launch staff has been seeing with the LH2 umbilical electrical cable are measurement transients throughout power-up that might exit of anticipated ranges for a bit bit when first powering-up after which come again right down to nominal ranges. The Artemis 1 launch automobile is already in a powered-up configuration with Orion, ICPS, and Core Stage, so all of those are at a traditional, steady configuration. Nonetheless, the staff went by way of the launch commit standards which can be related to the measurements to find out criticality, redundancy, and pre-planned contingency procedures, which mainly permits the staff to take failures on these measurements understanding that there are redundancy on these measurements and might proceed to launch. There’s redundant information coming throughout that interface from the rocket and spacecraft to the ground-side.
The staff charged with engaged on the LH2 umbilical electrical cable set to work late final Sunday night time to the MLP tail service mast to change-out the LH2 electrical cable and carried out a sequence of wring-out exams on that cable. When that didn’t appear to treatment the “momentary transient alerts” points that solely happen on power-up, the bottom recepticle aspect, positioned on the again of the LH2 tail service mast umbilical plate, was changed-out, adopted by a sequence of retests. That didn’t resolve the difficulty. Nevertheless, the Mission Administration Workforce, echoing feedback within the earlier night time’s briefing, believes that these points don’t violate a launch commit standards.
The staff working this, in accordance with Parson, “… did a extremely good job wringed-out all the information figuring out the chance posture, all measurements going by way of there, the place redundancy happens, and what launch commit standards are related to them.” Tonight, the J8 connector on the Core Stage shall be changed-out, to be adopted by exams.
Throughout immediately’s Mission Administration Workforce assembly, the standing of the LH2 umbilical electrical connector positioned on the J8 port was reviewed. The MMT when by way of the standing of the elimination and alternative and the work that was accomplished and any findings on account of that; the publish elimination and replacements programs standing checks. There are not any modifications within the posture as they head into the launch try. The launch commit standards have been reviewed and the staff agreed that the as-written launch commit standards have been the suitable posture to have heading into the subsequent launch try. That’s largely as a result of there’s loads of programs redundancy because it pertains to the alerts which can be wanted to be verified as a part of the launch commit.
The unanimous suggestion of the staff was that it was in a very good place to proceed with launch countdown with the measurements it has, which was based mostly on the criticality and redundancy posture that they’ve. They assume they’ve a extremely sturdy system with the variety of measurements in different areas.
Requested when he may really feel a way of aid, Parsons mentioned that the load shall be lifted from his shoulders when fast-fill of LH2 begins and doesn’t trigger hassle. The work achieved in the course of the cryo loading check on September 21 led to loads of understanding of what’s going on on the LH2 4” and eight” quick-disconnects that connect to the bottom of the launch automobile. The cryo staff is extra assured that even that the loading procedures will work, that they know the right way to load LH2 whereas placing the least quantity of strain on the seals of the 4” and eight” LH2 quick-disconnects. There’s a purge can round every of the quick-disconnects that’s constantly flooded with helium and accommodates hazardous gasoline measurements coming by way of that space. Launch necessities enable for “momentary transients”, or small spike, of LH2 leakage of hydrogen to concentrations of as much as 10% as LH2 strain will increase within the umbilical as long as that leak is for less than a small period of time. Throughout the cryo tanking check, there was a momentary spike of LH2 as much as a focus of 10% when the strain within the LH2 umbilical elevated from 2 psi, but it surely rapidly got here down. That the difficulty didn’t final leaves Parson with a reasonably good feeling that issues are dialed-in.
The one open motion that was taken out of the launch -2 day overview pertains to the Orion RTV materials delaminating seen throughout Hurricane Nicole on the east-side of the automobile, or roughly the 270 diploma mark within the Orion coordinates, on the Orion automobile’s aerodynamic shell, or ogive (pronounced “o-jive”), the place it meets up with crew module adapter. There was a ten foot lengthy strip of the RTV delaminated in the course of the storm.
The aim of that RTV materials is to fill the hole that exists between the LAS ogive and the crew module adapter. There’s a small space the place the 2 meetup the place there’s an aerodynamic barrier that might trigger a little bit of air circulation underneath the LAS ogive as a result of turbulent move because the Artemis 1 automobile ascends that might end in aerodynamic heating. To get rid of that small hole, the RTV materials is put in to create a flush, streamlined, aerodynamic floor.
There’s a small chance, larger than non-zero, that extra RTV comes-off of the automobile throughout ascent. At a prime stage, the “threat posture” hasn’t elevated. The Mission Administration staff believes it has a robust flight rationale to help that time. To have an opposed occasion in flight, extra RTV wants to return off that impacts the a part of the launch automobile, that a part of the automobile must expertise “essential harm”, and there are restricted elements that might be uncovered to that due the particles transport and their location to the place the RTV could be liberated.
The RTV is prone to tear-off, breaking-off in smaller items. RTV materials could be very pliable and has a low-lift coefficient aerodynamically. There was a witness pattern within the MMT assembly immediately that was 12” lengthy. The fabric could be very skinny, lightweight, and really pliable. NASA has loads of expertise with this RTV materials, which has been flown on many earlier automobile, together with Exploration Check Flight 1 in 2014 and Ascent Abort Check 2 in 2019. RTV materials was put in in a really related space in these check flights and materials within the interface of the LAS ogive and crew module adapter was not seen to liberate throughout aerodynamic flight.
The one time frame the place there’s an publicity to have sufficient vitality the place the mass of any RTV that have been break-off and comply with a really particular trajectory and affect the automobile downstream is within the Mach 2-3.5 vary, or 80-100 seconds in flight. That’s the slim window of publicity the place the rocket is accelerating quick sufficient however there’s sufficient environment to slow-down something coming off the automobile sufficient that there’s peak affect vitality.
The almost definitely space that RTV may affect is on the launch automobile stage adapter, or LVSA. There have been considerations about areas of the interior stable rocket boosters, the bottom of the boosters, and cable trays that run alongside each the ICPS and Core Stage.
The LVSA is a tall, conical function that sits on between the highest of the SLS Core Stage and the bottom of the ICPS. It takes the diameter of the Orion spacecraft and extends it out to the diameter of the SLS Core Stage.
The LVSA is a really sturdy piece of {hardware}. It weighs about 10,000 lbs and is used to translate the 8.8M lb of thrust at lift-off of the boosters and Core Stage’s 4 RS-25’s into the ICPS, which at 45 ft weighs 71,605 lbs, and Orion spacecraft stack, which itself is 67 ft and weighs-in at 72,000 lbs. It’s an inert piece of {hardware}–it doesn’t have gas, avionics, or different mission essential {hardware}, and performs solely a structural position.
A further space that might be impacted is the interior areas of the stable boosters subsequent to the Core Stage. The danger of this was thought of average relative to the LVSA.
The Core Stage and the ICPS have been thought of low-risk. The at-risk areas for each the ICPS and Core Stage have been the programs tunnels, that are small aerodynamic protrusions the place cables are run for communications.
The stable rocket boosters have been thought of a average threat as a result of particular areas the place there are separation motors on the very base of every booster.
Yesterday, when the Mission Administration Workforce met, there was a overview of the standing of that delamination and the chance of a reoccurance throughout flight. The MMT determined at the moment that it wanted a bit extra time to overview the flight rationale. The launch staff got here again with a flight rationale based mostly on a confirmed methodology termed, “The Seven Components of Good Flight Rationale”. The MMT regarded throughout the complete automobile stack, from the Orion spacecraft to the bottom of the stack, and the MMT agreed that the chance was bounded by present hazards–there are different identified particles sources and hazards–and hazards experiences the staff had that have been established effectively earlier than the company flight readiness overview.
Mission Lack of Automobile: 1/125 (0.008) might develop by larger than two decimal factors as a result of Hurricane Nicole, nonetheless, Launch Commit Standards (LCC’s), of which there are 489, haven’t modified as a result of hurricane.
Mission Supervisor Sarafin requested the Mission Administration Workforce members if there have been any dissenting opinions, there have been none, and the flight rationale of leaving the lacking RTV materials was accepted.
There are 10 cubesats positioned within the Orion Stage Adapter. 4 of the cubesats had their batteries topped-odd when the Artemis 1 automobile was within the Automobile Meeting Constructing (VAB). There’s one cubesat with a science mission to map the lunar volatiles that has a low cost on its battery which will affect its capacity to perform its mission. The remaining 5 cubesats have sufficient cost to final their full mission period and achieve their missions.
There are three manikins positioned within the Orion spacecraft that by way of mass the identical as an precise crew member, leaving the spacecraft one crew member mild. There are mass simulators and scientific and know-how demonstration payloads on the Orion spacecraft to simulate the meals and different consumables, gear, and kit that might be on a lunar mission.
Additionally positioned throughout the Orion spacecraft are lively and passive radiation dosimeters to tell the flight atmosphere that astronauts will expertise because the Orio spacecraft leaves low-Earth orbit to deep area. Because the Orion spacecraft transits from low-Earth orbit, by way of the Van Allen radiation belts the place there are concentrations of areas of deep area radiation, and into deep area the place there isn’t a shelter from deep area radiation equivalent to that supplied by the Van Allen radiation belts. The Orion spacecraft will then upon return transit by way of the Van Allen radiation belts earlier than rendering the Earth’s environment and splashing-down.
One final payload is the zero-G indicator, Astro Snoopy, in partnership with the Schultz Basis, who’ve been staunch advocates of the nation’s area program. The Silver Snoopy is awarded for flight security.
Tidbit: The Orion spacecraft mass will go from 72,000 lbs on launch to 58,000 upon LAS jettison, to 12,000 lbs on splashdown.
The MMT is continuing to the subsequent choice gate to set-up for the Nov. 16 launch try and there’s no change to aim the Artemis 1 launch at that date. The MMT is comfy launching with the identified points.
There are three buckets of standards that might change a launch try from go to no-go. There are the launch commit standards which can be the 489 LCC technical must-meet standards, climate standards, and vary security standards.
The subsequent choice gate for the Mission Administration Workforce happens on Nov. 15 at 2:30 EST with the start of tanking of LH2 and LOX.
