Saturday, February 13, 2016

A Song of Ice and Firing Stands

Ice cares not if you have AWD, Mr. Subaru.
I love Huntsville, Alabama. Really, I do. In fact, it's one of my favorite places to visit, and were it not for me being so far along in my career, I'd likely be looking to call 'Rocket City' home. However, the city that helped build America's manned space program hides a sinister secret - a "monster" who looks to snatch unsuspecting motorists from the apparent safety of the elevated arterial roadway and hurl them willy-nilly into the concrete barriers separating travel lanes from the near interminable drop to the ground below.

I know this monster. I've met this monster. I've *survived* this monster. On my birthday, of all days, this beast chose to rear its ugly head and attempted to add me to its collection of broken and charred victims. But not this day. My trusty steed - the venerable Forester - quickly leapt into action, deftly dodging left...then we were locked in an epic battle with Huntsville's silent killer: snowy roads.

OK, perhaps it wasn't quite so dramatic...but I *did* do a bit of dodging to the left and right...mostly because I started sliding on the ice and was doing all I could to keep from hitting the wall, or the other cars sharing the road with me. I don't care how good a driver you are, or what kind of car you drive, ice is the great equalizer. With the 'pucker factor' having risen to dangerous levels after my brief, but near-catastrophic, encounter with the icy roads, I decided to get the heck off the 'skyway' and move down to the surface streets, which I hoped would be clearer.

I liked the framing of this shot. That's it.
So, what dragged me out of a safe and warm hotel room in a city nearly four hours from home? NASA was hosting a Social event at many of their Centers across the country to mark the 2016 'State of NASA' address by Administrator Bolden. Marshall Space Flight Center (MSFC) in Huntsville was one of those sites, and had invited nearly twenty social media participants to visit the Center.

I know that I've visited MSFC many times - often writing about the trip here in my blog - and I almost feel like it's "my" Center. In fact, I had been to Marshall a scant two months prior to report on the near-completion of the stand meant to stress-test SLS's massive liquid hydrogen tank. Nevertheless, my passion and interest in our nation's space program is such that I could likely visit the Center weekly and not tire of it, or feel jaded about the major role Marshall has played - and continues to play - in America's space flight heritage.

Being the Center responsible for designing, testing, and validating SLS, one would expect any Social event at MSFC to focus heavily on that vehicle...and this day was no exception. Marshall's newly-appointed Center Director - Todd May - greeted the group, welcoming us to the Center and gave us a brief overview of Marshall's activities over the past year, and then took a moment to answer questions.

Marshall Space Flight Center Director Todd May
With the possibility Congress could direct NASA to launch the proposed 'Europa Clipper' mission on SLS, I asked May if the Michoud Assembly Facility (MAF) - which operates under Marshall's "umbrella" - could accommodate that need along with the tentative flight date of EM-2. According to May, though the nominal production rate for SLS will support a cadence of one flight per year, capacity at MAF will allow for a surge rate of two SLS launches per year, and a 'spike' capacity of three per year. Any cadence higher than that, or a sustained rate of two-plus vehicles per year, would require expansion at MAF.

After a few more questions, the group heard from two engineers working on the SLS program - Michelle Tillotson and Nick Case - before heading to the avionics area. There, engineers and programmers are 'tweaking' SLS's flight computers, followed by simulated launches, to gather data about how the rocket will perform throughout nominal - and off-nominal - flight profiles. Even a shortened simulated launch can generate several terabytes of data for the engineers to examine. As various components of SLS move from design to testing to qualification stages, that real-world performance data is integrated into the testing regime. In fact, shortly after the successful test of the new 5-segment booster in March 2015, Orbital ATK had delivered the raw data to the SLS engineers in Huntsville.

Yes, I took a selfie at a rocket test stand. Not ashamed.
Departing the avionics area, the group boarded the bus to travel to the test stand area at Marshall. This part of the Center has a rich history - here, von Braun and his team tested many of the rockets which would carry America's astronauts to Earth orbit...and beyond. Situated between the two SLS test stands currently under construction is the massive firing stand used to test the mighty Saturn V rocket. It's hard to imagine the sound which must've roared through the Tennessee River Valley when those engines were tested.

Though quiet this day, the stand nonetheless presented an imposing sight: its massive concrete and steel structure stood as a testament to the power it was built to restrain. With snow continuing to fall in fits and spurts, and a healthy wind chill to boot, the group was invited to take an elevator ride midway up the structure to get a view of the two SLS stands being built nearby. Once complete, those stands will push, pull, and twist the core stage's liquid hydrogen and liquid oxygen propellant tanks, stressing them to flight limits, and beyond, to ensure SLS will be the safest vehicle to launch crew and cargo.

Les Johnson - Dep Mgr, NASA's Advanced Concepts,
compares the thickness of the sail to one's hair (or lack thereof).
Thoroughly chilled to the bone, we dutifully boarded the bus to head to the 'flat floor' facility to meet with some engineers working on secondary payloads which will fly on SLS. One of the more interesting payloads is a solar sail. This 86 square-meter sail is made out of a material the thickness of a human hair - 2.5 microns. The 'pressure' of sunlight will push on this material, accelerating the sail at a slow, but steady, pace without requiring fuel or engine. Smaller sails have been tested previously, but SLS will give these smaller secondary payloads the unprecedented opportunity to go beyond their usual "playground" of low-Earth orbit (LEO) and operate in cislunar space. Without the drag of Earth's atmosphere, thin though it may be in LEO, the sail should be able to accelerate slightly more rapidly (though 'rapid' is definitely a relative term when one is talking about the pressure of sunlight), providing more meaningful data to scientists.

Our final stop of the day was back at the US Space and Rocket Center. There, the group was given a tour of the new International Space Station (ISS) exhibit, which includes a scaled-down version of the real-life Payload Operations Center (POC) at Marshall, along with a "high fidelity" replica of many of the ISS modules. Save for the lack of cables, computers, and various clutter one many expect to find on an operational space station, the ISS mock-up is an accurate analogue to the real deal.

This is on the ISS. Really.
One of the more amusing stories came from 'Paycom Penny' (Penny Pettigrew). The astronauts on-station can speak with the ground operations not only through the expected ISS-ground radio communications, but also through more traditional means - a.k.a., a phone call. Pettigrew recounted an instance when she was heading home from a shift at the POC only to have her cellphone ring as she was on the highway. CallerID doesn't identify it as 'Space Calling' (though how awesome would *that* be?!?), so she wasn't necessarily expecting there to be an ISS-based astronaut on the other end of the call. Penny said when an astronaut calls, you'd better believe that's a situation when one pulls over to the side of the road to give the caller one's undivided attention.

Knowing that I had to take the long route back home in order to avoid the snowy conditions through the mountains, I excused myself from the last, optional bit of the day and headed home. As always, the Social was thoroughly enjoyable, and it's always nice to meet fellow space enthusiasts.

I would like to thank the people at Marshall, and at the Space and Rocket Center, for inviting the group out to take part in this NASA Social event. It's incredible to consider that a "normal person" like me has the opportunity to participate in something like this.