Damaged/Missing Tile Question ?

[seth_381]

Someone here on Space.com was saying it wouldn't matter if tiles are missing or damaged on the underside of the orbiter and wouldn't that be incorrect because of the major heating in that area.I know many are damaged but what if some were missing ? Like lets say 3-5 would it cause another columbia or just damage that could be repaired ?

 

[shuttle_guy]

In most cases one missing tile on the belly would not be a problem for the re-entry since the laminar flow over the cavity
would prevent most damage. More than one missing tile in the same place would be a problem and could cause a burn through of the vehicle skin. How serious that would be depends on what was damaged inside the Orbiter.

 

[Swampcat]

I remember STS-1 and all the concern over so many missing tiles after landing. From Astronautix.com:

Post-flight inspection of the Columbia revealed that an overpressure wave which occurred when the SRB ignited resulted in the loss of 16 heat shield tiles and damage to 148 others. In all other respects, however, Columbia came through the flight with flying colors, and it was to fly the next four Shuttle missions.

From STS-2 onward, and after modifications to the Sound Suppression System, tile loss was no longer a major issue.

 

[seth_381]

I know about the sound supression system, I know they miss one or more sometimes but shuttle_guy told me what I wanted to know and it also explains to me the reason why STS-27 came home safely (uninterrupted plasma moving past the damaged tile).

 

[vulture4]

white tiles have been lost and black tiles have been chipped, but I only remember one flight that lost a complete black tile from the lower surface; there was some slumping of the aluminum skin but no burn-through.

 

[bdewoody]

I think over the years there are several areas where they don't even have the white tiles anymore as those areas proved not to be exposed to extreme heat on re-entry.

 

[seth_381]

well I've been doing some reading on the subject and it turns out the shuttles have came close to destruction many more times than I thought it's a good thing the general public doesn't know. I like the shuttles but the number of times it's came close to destruction is unacceptable.

 

[MeteorWayne]

Care to post the results of your research that indicate that? (Please don't use the Combustion Instability thread here at SDC )

 

[seth_381]

Well it isn't as bad as I made it sound but from all of these times an orbiter and crew were put at risk more than usual

STS-1 : Missing tiles and incorrectly installed near the ET door and lead to excessive heating leading to damage plus an incorrectly installed gap filler by the landing gear door causing damage and buckling of the door.

STS-2/51C : The first/continued evidence of O-Ring Burn through and if you wannabe picky you can consider STS-1 through 25 all at a higher risk.

STS-9 : Simple enough APU fire during landing due to a leak.

STS-27 : 700 Tiles Damaged

Now there's another case I've heard of and it is shortly before the Columbia Disaster and it involved a form strike that did lead to some damage. STS-93 could also go in the list because of the leak during lauch. Anyways my point is there shouldn't be anymore than one or two cases at most of higher risk than usual. It's like the shuttle is a flying pinto.

 

[MeteorWayne]

Just curious about the STS-27 incident you cite. Got a link? I'd like to read about it since I had not heard of that before.

thanx. MW

 

[seth_381]

Well here's the first link to Wiki (scroll to bottom) http://en.wikipedia.org/wiki/STS-27 the second is a forum post http://forum.nasaspaceflight.com/index. ... ic=16429.0 and third is a picture of the orbiter damage zoomed http://galaxywire.net/wp-content/upload ... side-2.jpg if you don't know the damage is suppost to have been caused by debris from the SRB's. My most credible source is NASA's In-Flight Anomaly Database http://www.jsc.nasa.gov/news/columbia/anomaly/ open the one of STS-27 and scroll down to page 6.

 

[job1207]

interesting report....

 

[MeteorWayne]

Thanx, seth.
MW

 

[seth_381]

your welcome I wish I could find more about the damage but sadly it was a DOD mission. I wonder if we'll ever hear about what happend during those DOD missions down the road someday ?

 

[bdewoody]

your welcome I wish I could find more about the damage but sadly it was a DOD mission. I wonder if we'll ever hear about what happend during those DOD missions down the road someday ?

Apparently not enough for the military to want to keep the shuttle flying.