NASA has reportedly cancelled a host of planned Shuttle External Tank modifications based on intensive ET study during the period of resummed flight following the Columbia catastrophy.
The change in plans is not related to delays in the delivery of new ETs, delivery of the first built completely after Columbia and already changing the Space Shuttle's accelerating planned flight schedule.
Modifications beyond those already made, scheduled in a second phase of ETs to be built for the last flights of the program, set to end in 2010, are now thought unnecessary.
Whether the modifications will be included in the slightly larger External Tank for Ares V and the smaller upper stage liquid Oxygen and Liquid Hydrogen tank booster on Ares I, set to begin testing in 2009, to be carried aloft using by a similarly enlarged Solid Rocket Booster design, is not yet known.
