Tag: SLS

NASA managers have given the go-ahead to the scheduled launch of the agency’s SLS rocket for 1:04 am (Eastern) on November 16, 2022, despite the existence of some detached caulking that Hurricane Nicole had pulled free.

Engineers examined detailed analysis of caulk on a seam between an ogive on Orion’s launch abort system and the crew module adapter and potential risks if it were to detach during launch. The mission management team determined there is a low likelihood that if additional material tears off it would pose a critical risk to the flight.

Technicians also completed replacing a component of an electrical connector on the hydrogen tail service mast umbilical. While swapping the component did not fully fix the issue, engineers have redundant sources of information supplied through the connector.

The launch window is two hours long. As this is a night launch, it will be quite spectacular, no matter what happens. I will embed the live stream tomorrow in the early evening, for those who wish to watch NASA’s multi-hour propaganda stream. My suggestion would be to find a better use of your time until around 12:50 am (Eastern). Then would be a good time to tune in.

Despite repeated assurances that the November 16, 2022 1:04 am (Eastern) launch of NASA’s SLS rocket remains on target, managers have also noted that damage to a small piece of caulking at the base of the shroud protecting the Orion capsule remains an issue that could cause a scrub.

But high winds from Nicole caused a thin strip of caulk-like material known as RTV to delaminate and pull away from the base of the Orion crew capsule’s protective nose cone at the top of the rocket. The material is used to fill in a slight indentation where the fairing attaches to the capsule, minimizing aerodynamic heating during ascent. The fairing fits over the Orion capsule and is jettisoned once the rocket is out of the dense lower atmosphere. “It was an area that was about 10 feet in length (on the) windward side where the storm blew through,” said mission manager Mike Sarafin. “It is a very, very thin layer of RTV, it’s about .2 inches or less … in thickness.”

Engineers do not have access for repairs at the pad and must develop “flight rationale,” that is, a justification for flying despite the delaminated RTV, in order to proceed with the launch. Managers want to make sure any additional material that pulls away in flight will not impact and damage downstream components.

In plain language, NASA managers would either have to issue a waiver that says this small piece of caulking poses no risk, or scrub and roll the rocket back to the assembly building to fix it. The second option would delay the launch another month, at a minimum.

A waiver however would continue NASA’s pattern with the shuttle (and continuing with SLS) to dismiss potential engineering problems simply to avoid schedule delays. With the shuttle, this pattern twice caused the loss of a shuttle and crew. With SLS, NASA has already waived by more than a year its rules concerning the stacked life of the rocket’s solid-fueled boosters. Agency managers have also waived the full test requirements from the dress rehearsal countdown, so that this test did not test everything it should.

It is expected that NASA managers will announce the waiver today on this problem. Whether it matters when the rocket goes through maximum dynamic pressure shortly after lift-off will likely determine the future of SLS.

NASA’s SLS rocket has apparently successfully survived on the launchpad the hurricane-force winds from Nicole, though engineers will need to inspect the rocket to see if there is any less obvious damage that might delay the now scheduled November 16th launch.

With blastoff on a long-delayed maiden flight on tap next week, sensors at pad 39B recorded gusts as high as 100 mph atop a 467-foot-tall lightning tower near the rocket. But winds at the 60-foot-level, which are part of the booster’s structural certification, peaked at 82 mph, just below the 85 mph limit.

The observed winds were “within the rocket’s capability,” said Jim Free, manager of exploration systems at NASA headquarters. “We anticipate clearing the vehicle for those conditions shortly.”

“Our team is conducting initial visual check outs of the rocket, spacecraft and ground system equipment with the cameras at the launch pad,” he tweeted. “Camera inspections show very minor damage such as loose caulk and tears in weather coverings. The team will conduct additional on-site walk down inspections of the vehicle soon.”

If no issues are found, the countdown will begin on November 14th.

NASA today announced that it will make its next attempt to launch its SLS rocket just past midnight on November 14, 2022.

NASA is targeting the next launch attempt of the Artemis I mission for Monday, Nov. 14 with liftoff of the Space Launch System (SLS) rocket carrying the Orion spacecraft planned during a 69-minute launch window that opens at 12:07 a.m. EST. Artemis I is an uncrewed flight test to launch SLS and send Orion around the Moon and back to Earth to thoroughly test its system before flights with astronauts.

This is the second launch opportunity in the November launch window, as shown in this graph [pdf]. It will result in a 26-day mission for the Orion capsule to and from lunar orbit, returning on December 9th.

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.

NASA managers today decided they will not attempt another launch of SLS during the present launch window that closes on September 6, 2022, and will bring the rocket back to assembly building for more detailed trouble-shooting.

Engineers not only need to solve the hydrogen fuel leak in a fuel line connection that caused today’s launch scrub, they will also have to replace the flight termination batteries needed in case the rocket has to be destroyed during liftoff because it is flying out of control. These batteries only have a few weeks life, and the launch delays this week caused them to reach their limit.

The next launch windows are either from September 19 to October 4, excluding September 29-30, or October 17 to October 31, excluding October 24, 25, 26, and 28.

At that point SLS’s two solid rocket strap-on boosters will have been stacked for about two years, one full year past what NASA once considered their safe lifespan. The agency has waived that rule for SLS, but waiving it for more than a full year might simply be too risky. If the boosters need to be replaced, that will delay the launch by at least another three months, at the minimum.

Right now the odds remain high this launch will not occur in 2022.

NASA has resumed the countdown for the launch of the SLS rocket on Saturday, September 3, with a two-hour launch window beginning at 2:17 pm (Eastern).

The live stream is available here.

NASA engineers have now concluded that the improper temperatures in one engine in SLS’s core stage that forced the August 29, 2022 launch to be scrubbed were caused by a faulty sensor, and that the actual temperatures in the engine were correct.

During a news conference on Tuesday evening, NASA’s program manager for the SLS rocket, John Honeycutt, said his engineering team believed the engine had actually cooled down from ambient temperature to near the required level but that it was not properly measured by a faulty temperature sensor. “The way the sensor is behaving does not line up with the physics of the situation,” Honeycutt said.

The problem for NASA is that the sensor cannot be easily replaced and would likely necessitate a rollback to the Vehicle Assembly Building at Kennedy Space Center in Florida, a few kilometers from the launch pad. This would delay the launch of the rocket at least into October, and the space agency is starting to get concerned about wear and tear on a rocket that has now been stacked for nearly a full year.

With this SLS rocket, NASA management is now trapped between a rock and a hard place. The rocket’s solid rocket boosters has been stacked for just short of two years, almost a full year beyond their use-by date. Moreover, there are batteries on the rocket that only function for about a month before they must be replaced. Their replacement date is September 6th, which means if NASA cannot get the rocket launched by that date it will have to return it to the assembly building, delaying the launch to at least October. If it has to replace the solid rocket boosters the launch will likely then be delayed until next year, which will seriously impact the second SLS launch, set to send astronauts around the Moon and back.

At the moment the launch is scheduled for a two hour launch window beginning at 2:17 pm (Eastern) on Saturday, September 3, 2022. The countdown will be live streamed here. At the moment the weather for Saturday has improved, with s 60% chance the launch can proceed.

NASA will make its next launch attempt of its SLS rocket on September 3, 2022, with a launch window opening at 2:17 pm.

However, the weather might not cooperate. At present forecasters only give a 40% chance for launch.