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Resolute - before you do your calcs, take a look at this:

All - this is a very interesting story, go to the story, not the bump link. Quote from the story:

In the Columbia's case, Crater predicted "significant tile damage," with gouge depths that actually exceeded the thickness of tiles in several critical spots. For example, the tiles protecting the wheel well are about two inches thick. Yet Crater calculated that the foam would penetrate 3.4 inches in this part of the wing.

The Boeing team did not accept Crater's predictions at face value. The program was "designed to be conservative," they noted, and so has sometimes "overpredicted penetration of tile coating significantly."

Another factor in their judgment was data from a 1992 Columbia mission that they believed had absorbed a "potentially" similar debris impact. In that case, the debris left a gouge only a half-inch deep.

There was a difference between the flights, though. In 1992, the debris was thought to have struck at an angle of 3.2 degrees. This time, the predicted angles were far sharper, which the Boeing team was careful to point out would alone significantly increase the damage. Still, for reasons not spelled out, the engineers concluded that "even for worst case," the foam debris would leave behind at least the last quarter-inch of tile, giving the wing at least some thermal protection.

The report did not spell out another thing: why the Boeing team never calculated how much worse the damage would have been if the debris was actually ice, or partly ice, and not foam.

As the Boeing team noted, previous NASA research had documented the dangers of ice debris: if it struck the wing's leading edge at a sharp enough angle — greater than 15 degrees — it could penetrate the tough carbon coating that protects the edge from re-entry heat, potentially leading to a catastrophic burn-through. In the Columbia's case, NASA calculated that the debris could have hit the edge at an angle of 22 degrees.

Outside experts, including many with deep institutional ties to NASA, are expressing polite concern that the engineers erred by not considering more possibilities.

"It was very good as far as it went," Dr. William Schneider, former assistant director of engineering for NASA, said of two reports prepared by Boeing engineers. But, he added, "They still needed to do more tests."

http://www.freerepublic.com/focus/news/845414/posts?page=3#3

Thanks for the intriguing posting.

Snopercod seems hell bent on blaming OMDP at Palmdale. I don't know the work specs at the last OV-102 OMDP.

Speaking as a Californian, I must say that each time KSC returned a bird, they would find interesting things.

Snopercod apparently chooses to ignore these facts and only focus on the observations of NASA/USA teams at KSC.

As for my bias towards Palmdale, suffice it to say that I'm sick and tired of hearing KSC console operators pontificating about how poor the people at Dryden or at Palmdale are.

The work at Rockwell was done well and under schedule with the vehicles being returned to Florida on time and under schedule.

I suppose sometime between the previous OMDP and the one in 2000 that OV-102 had ongoing problems. LA Times today reports that there were wiring problems identified during the last OMDP.

While Snopercod can snidely whiplash the Boeing team at OMDP, the reality is that Rockwell International's crew always took their lickings and said little to argue. The reason was clearly reinforced with the RI guys. The execs always told RI employees that they were to view NASA as the customer and the customer's interests always came ahead of RI's interest. The reason was that Don Beall always reinforced that we were to love our nation greater than our own interests. I've taken that to heart with the rest of my life.

Snopercod doesn't make sense to me. He says he was sitting in the LCC FR during 51-L. Then, when questioned about Ken Hollis' fiasco, he claims that Hollis got fired for talking too much about his job (which is correct). Frankly, Jim Oberg is in the same boat. Ironically, Snopercod then claims that he doesn't know who Jesse Moore is. I believe that any personnel in the Firing Room could have looked up a few rows to see Jesse Moore looking back at them?

Or perhaps, I am just another pud-knocker from Edwards?

It's not Bo

I read the link (thank you) and did more calculations anyway, for the sake of thoroughness. I applied the same data from post #2431, and assumptions as stated in post #2440, but varied Coefficient of Drag (Cd), from 0.6 up to 1.5. For each case I tabulated the time of transit (from detachment to impact), and relative impact velocity. As before, assumed 53.4 feet of axial travel from external tank attach point to wing impact. The data show that for higher Cd (more drag), the transit time decreases and relative impact velocity increases.

Coefficient of Drag (non-dimensional)	Time of Transit (s)	Relative Impact Velocity (mph)
0.60	0.260	495.98
0.70	0.244	525.08
0.80	0.231	551.21
0.90	0.220	574.92
1.00	0.210	596.67
1.10	0.202	616.72
1.20	0.195	635.37
1.30	0.189	652.76
1.40	0.183	669.05
1.50	0.178	684.42