>> Thursday, January 7, 2010
Aron asked: What does this mean? Orbiter: OV-105 / ET-134 / SRB BI-141 / RSRM 109 (VAB HB-1)
Let's break it down:
The first bit, OV-105, is the Orbiter Vehicle Designation, the one that tells us which Orbiter it is (as we still have three). In this case, OV-105 designates, for instance, Endeavour, the newest Orbiter, constructed as a replacement for Challenger in 1992. Only five space-worthy operational Orbiters were built: OV-099 (Challenger), OV-102 (Columbia), OV-103 (Discovery), OV-104 (Atlantis) and OV-105 (Endeavour). There were two other developmental prototypes: OV-098 (Pathfinder - a structural model) and OV-101 (Enterprise). Enterprise was designed to be the original Orbiter design, but without engines or heat shield; i.e. not spaceworthy. However, they did tests with Enterprise, including vibration tests, mated (to the Boeing) flight tests, and detached landing tests.
Why "Orbiter" and not "Shuttle" - well the part that comes back, the plane-like part, that lands some 4-24 days after launch is technically called an Orbiter in the Shuttle world. The whole system, Orbiter, External Tank, Solid Rocket Boosters, is called the Shuttle Transport System (hence the STS in the flight designation: STS-107, for instance). Just so you know
That leads us to the ET-134. That designates which External Tank it is. Each flight requires a new ET (they are not reusable and burn up in reentry). I think they are just numbered in order of construction, though they are not always flown in that order.
Similarly, I believe the SRB (which stands for Solid Rocket Booster) now called the RSRM for Reusable Solid Rocket Motor (also Redesigned Solid Rocket Motor) are just listed by number. I often hear the terms RSRM and SRB used interchangeably (even in technical circles), but, technically the RSRM is a redesign of the original SRBs. The SRBs/RSRMs have always been reusable and the cases are plucked from the drink not long after launch, refurbished, reloaded with solid rocket fuel and reshipped to KSC.
The last bit, I believe, has to do with where it sits in the Vertical Assembly Building (VAB), as in which High Bay (HB). But I'm speculating there.