posted 09-23-2005 01:28 AM               

I could always identify Columbia by the larger area of black tiles around the wing root.

posted 10-14-2008 03:55 PM               

Challenger: Visual cues to me were the fact that it had LRSI on the wings and below the payload bay doors in the stair step pattern like Columbia had, but it didn't have the black chines. The nose also had white tiles like Columbia as well. Take away the colors of the tiles and both Challenger and Columbia had very similar TPS patterns.

The tile pattern around the side hatch is indeed another distinguishing feature, although the pattern it had for STS-51L didn't pop up until a couple flights earlier. Prior to that it had a side hatch pattern similar to that of Columbia.

Discovery: Biggest visual cue topside is there are some extra black tiles below window number 5 on the pilot side when both Atlantis and Endeavour have white tiles there. Other then that, the three orbiters are practically triplets of one another.

Other things I noticed after the return to flight were Discovery had some of its old RCC panels alongside the new ones resulting in a very distinctive dark, dark, light, dark appearance as you look down the wings. Atlantis and Endeavour still kept uniform appearances to their RCC panels (probably because Discovery had some RCC panels removed for the CAIB testing). The TPS patterns on the bottoms of the orbiters are also pretty distinctive when you see images of their RPM backflips.

Atlantis: Virtually identical to the others. Only really noticeable thing I saw when Atlantis was being prepped for return to flight was the RCC wedge piece just behind the nose RCC cap was bright gray in coloring while Endeavour's and Discovery's was much darker (must have been replaced during OMDP).

Endeavour: Early in the program, Endeavour was easy to identify since it was the cleanest looking orbiter for about its first 6 flights. It took about ten flights to really get a grungey appearance in its TPS pattern. Endeavour was the first shuttle built with a drag chute housing on the tail and this is the easiest feature to spot during the NASA wurm era marking period. But both Atlantis and Discovery (and Columbia) had the dragchute housings retrofitted to them in the early to mid 1990s as well during OMDPs.

Now looking at the bottom of Endeavour, Discovery and Atlantis during RPM manuevers, there are some noticeable patterns to them that I have seen. One thing to keep in mind about shuttle TPS is it is constantly evolving. New tiles replace older ones and while new tiles start out black in color, they gradually fade to various gray shades over the course of several reentries. As such, you tend to see a gray bottom with some darker gray patches and a few black ones, depending on what tiles were replaced when. But since we didn't really begin to see images of the bottom until STS-114 anyway (both RPM and from the ET cameras), the patterns of gray shades tend to be easy identifiers on new imagery of the shuttles.

Discovery: The occassional lighter gray RCC panels on the wings are easy to spot in some images (most common images being from STS-114's RPM). Discovery also seems to have the largest amount of new black tile patches around the nose area (clusters of four or five tiles) while the other orbiters have more single black tiles and clusters of two or three.

Atlantis: The main gear door borders on Atlantis are almost completely surrounded by newer darker gray tiles while Discovery just has strips of newer black tiles on the inner edges of the main gear doors (inner as in towards the center of the body) and Endeavour only has some replacement tiles on the front edges of the main gear doors. If you see a distinctive dark border surrounding the main gear doors, it is probably Atlantis.

posted 10-15-2008 06:32 PM               

quote:

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Originally posted by blue_eyes:
When I was researching Columbia for my music CD, I stumbled across this fascinating site.

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