NASA details Ares launch pad timeline

The latest estimate for the Hubble servicing mission is September 2008, which – as with all future flights of the Shuttle after next month’s STS-116 – will launch from Pad 39A. However, the rescue Shuttle will sit on Pad 39B, on standby as the LON flight.

That rescue Shuttle will be the next scheduled orbiter to fly on the manifest (yet to be determined) – and once the stand-down for LON requirement is given, it will carry out only the third ever ‘rollaround,’ where the stack will rollback off Pad 39B, head down to the fork in the crawlerway, and then move forward to Pad 39A for its primary mission. That has only ever happened before for Shuttles on STS-35 and STS-61.

Constellation will then take over Pad 39B immediately after the LON requirement is stood down, allowing for the modifications to start in earnest on the pad, ahead of the 2009 test flight of Ares I-1 – the first of up to four test flights of the four segment plus dummy stage ‘stick’. Currently, the Constellation Manifest calls for two test flights and four launch abort tests.

Originally, Constellation was to take over Pad 39B on April 1, 2007, but that was officially reverted by a recent PRCB (Program Requirements Control Board) meeting, that restored the pad to Shuttle funding for the Hubble rescue mission.

Following the decision to keep Pad 39B available for the STS-125 LON flight, Constellation have worked on a plan that will allow some of the modifications to take place to the launch complex that will not impact on Shuttle operations. This has reduced the overall impact to just six months for Constellation work.

Kicking off the morphing of 39B will be the construction of three giant Lightning Protection Towers. These towers will begin to rise out of the ground at 39B next July, and are required given the ‘clean pad’ design for Ares, which differs from the Shuttle’s protection system that is a permanent fixture on top of the current FSS (Fixed Service Structure) – which will be dismantled for Ares.

The ‘clean pad’ also followed Saturn V heritage, meaning the supporting structures such as the LUT (Launch Umbilical Tower) will be a fixture on the Mobile Launch Platform – as opposed to being a fixture at the pad complex.

Work will also take place in the giant Vehicle Assembly Building (VAB) – where modifications will take place for Ares I-1 stacking at the latter part of 2008. Video and images of that stacking process for Ares I-1 is available on L2.

One of the recent ‘cool’ highlights of the modification plans for the launch pad is the construction of a ‘rollercoaster’ Emergency Egress System (EES) – which will begin around September 2008.

Projected to take place ahead of the Hubble mission will be the LH2 (Liquid Hydrogen) Bulk Propellant Storage Tank overhaul, which is expected to start around February 2008.

Around the same time, modifications will take place on MLP-1 – a current Shuttle Mobile Launch Platform – to support the Ares I test flights. This will be a phased modification, with the eventual change to a ML (Mobile Launcher) – and then the construction of a ‘super crawler’ able to carry the huge weight of the Ares V.