Behind The Black – Robert Zimmerman

Based on the present hurricane track, NASA managers are considering the possibility of leaving SLS on the launchpad so that they can go for a launch on October 2, 2022.

NASA managers will meet this evening to evaluate whether to roll back or remain at the launch pad to preserve an opportunity for a launch attempt on Oct. 2. The exact time of a potential rollback will depend on future weather predictions throughout the day and could occur Monday or very early Tuesday morning.

If they stay on the launchpad, it means the flight termination system is questionable at launch. If the rocket goes out of control during its first test launch — a not-unreasonable possibility for a new rocket — there is a chance the range officer will not be able to destroy it.

If they roll back to the assembly building, it means the rocket’s two solid strap-on boosters will either have to be replaced, delaying the launch months more, or the rocket will launch with two boosters that are questionable.

Every choice they face is a bad one, simply because this rocket is really not well designed for practical use.

In a briefing today, NASA officials confirmed that they are proceeding with their September 27, 2022 first launch of the SLS rocket, having obtained a waiver from the Space Force’s range office on testing the batteries for the flight termination system that would destroy the rocket should it begin flying out of control.

During a Sept. 23 teleconference, NASA announced an extension for the flight termination system battery certification, which expired after 25 days on Sept. 6. Now the Space Force’s Eastern Range has granted a waiver to allow the rocket to launch as late as Oct. 2 before needing to be returned to the Vehicle Assembly building to recertify the batteries.

The flight termination system is only used in the event the rocket veers off course during a launch anomaly.

Note that the 25 day use-by limit was actually an extension itself, as these batteries had been previously required testing every 20 days. Now the range is willing to let them go for as long about 50 days without testing, a two and half times increase.

If the rules before — based on engineering — said the batteries were not reliable after 20 days, why are those batteries now considered reliable up to 50 days? What facts or data does NASA or the Space Force have to allow this waiver? And if they have no data, it seems almost criminal to allow the go-ahead of this launch of a giant untested rocket on its first lift-off. Should something go seriously wrong — which is not that unlikely — and the flight termination system fails to work, we could see a very big rocket careening out-of-control into populated areas.

We all hope SLS launches with no problem on September 27th. We now have a really serious reason for that desire.

Regardless, the launch is now scheduled for a 70-minute launch window that opens at 11:37 am (Eastern) on September 27th, with a back-up launch window on October 2nd of 102 minutes beginning at 2:52 pm (Eastern).

Meanwhile, a developing tropical storm could put a kabosh on all these plans, forcing NASA to roll SLS back to the assembly building anyway. NASA managers plan to meet again before launch to make a decision.

NASA engineers today successfully completed the tanking test of the agency’s SLS rocket, completing all objectives after successfully dealing with a hydrogen fuel leak at the beginning of fueling.

The four main objectives for the demonstration included assessing the repair to address the hydrogen leak identified on the previous launch attempt, loading propellants into the rocket’s tanks using new procedures, conducting the kick-start bleed, and performing a pre-pressurization test. The new cryogenic loading procedures and ground automation were designed to transition temperature and pressures slowly during tanking to reduce the likelihood of leaks that could be caused by rapid changes in temperature or pressure. After encountering the leak early in the operation, teams further reduced loading pressures to troubleshoot the issue and proceed with the demonstration test. The pre-pressurization test enabled engineers to calibrate the settings used for conditioning the engines during the terminal count and validate timelines before launch day to reduce schedule risk during the countdown on launch day.

Teams will evaluate the data from the test, along with weather and other factors, before confirming readiness to proceed into the next launch opportunity. The rocket remains in a safe configuration as teams assess next steps. [emphasis mine]

The highlighted words are key. NASA has proposed a September 27, 2022 launch date. For that launch to occur, the rocket must remain on the launchpad, where it is impossible to check the batteries for operating the flight termination system used by the military range office to destroy the rocket should it go wildly out of control during launch. To check the batteries they need to roll it back to the assembly building, and one week is simply not enough time.

The vagueness of the highlighted language suggests that NASA has not yet gotten a waiver from the range for that date. Nor should it. Those batteries normally have a 20-day limit. On September 27th they will been unchecked for about 42 days, well past their use-by date.

This will be the first test launch of this rocket. Such first launches very frequently go wrong, and if SLS goes wrong, it would go wrong in a very big way, considering the size of the rocket. To do such a risky launch with a questionable flight termination system would not simply be improper it would be downright criminal.