Behind The Black – Robert Zimmerman

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.