Tag: spaceflight

STS-135 Atlantis NASAtweetup Writeup

Last Atlantis Launch for STS-135 by plemeljr
Last Atlantis Launch for STS-135, a photo by plemeljr on Flickr.

Here is my writeup for the STS-135 Atlantis NASAtweetup, an excerpt:

Once above the tower, the Shuttle elongates to a dark blob on the end of a matter-defying streak of pure light. It is unbelievably, eye-searing, bright. Then the sound of five engines drift over the water from three miles away. A force so strong, that if you were 400 yards away from the pad you would be incinerated and 800 yards away the acoustical wave would kill you. Three miles away, this force merely pushes you back; a low and steady bass which befuddles your mind into trying to figure out how the streaking blob and the animalistic scream fit together.

This is joy; joy of hearing a safe throttle back to relieve the astronauts of the massive gravity force; joy of hearing the throttle up command but knowing that in 1986 six astronauts and one teacher lost their lives at about this point; joy in hearing the CAPCOM call out in successive moments abort locations, knowing that the violent thrust behind the astronauts both increase altitude, and brings them into a safer orbit; joy that eight minutes and thirty seconds later the call, Press to MECO, is confirmed and the main engines cut off for the last time and the astronauts are in a safe, stable orbit.

STS-134 Space Shuttle Endeavour Post-scrub Briefing

Today’s STS-134 Space Shuttle Endeavour launch was scrubbed due to a malfunction of the heating elements on an Auxiliary Power Unit (APU) which controls the hydraulics which controls movement of the main engines (SSME), aero surfaces, basically everything on the orbiter. This was a main system, which had some redundancy, but an ascent and decent it is a critical part of steering the orbiter. So it makes sense that the launch was scrubbed. You can watch a snippet of the press conference above, or watch the whole Post-scrub Briefing (warning, long).
They won’t know until tomorrow how serious the issue is – it will take a bit more time to safe the Shuttle: mainly the ET hydrogen takes 24 hours to fully remove, burn-off then purge the tank with helium to make it safe to work on the Shuttle.
Right now STS-134 is set to launch no earlier than Monday at 2:33 pm, which will undoubtably be adjusted when they can get into the rear avionics bay to repair the heating system. According to Space Flight Now:

NASA managers do not yet know what it will take to resolve the problem, but they are hopeful a faulty thermostat in a heater circuit is to blame. If so, the shuttle could be ready for another launch attempt as early as Monday at 2:33:56 p.m.
But if the problem requires a cockpit fuse panel swap out, or installation of a replacement electrical box in the shuttle’s aft engine compartment, Endeavour’s launch on its 25th and final mission could be delayed until May 9 or 10, after the planned May 6 launch of an Atlas rocket carrying a missile early warning satellite.

Personally this is a disappointment as I had contingencies for both a 24 and 48 hour scrub, but a Monday launch basically is out of the question due to money, but also time: I would be back at work no earlier than Tuesday. And frankly the thought of waking up again at 5am to wait in a series of lines again wasn’t to appealing. Additionally, Monday isn’t a lock and I have other commitments. So I will be watching the ascent on NASA TV (which is pretty awesome, by the way).