First Davin, I want to say that I'm glad I've found someone who knows something about the topic here. And I appreciate the time you're putting in for me. I'm not posting this stuff to hear the sound of my own uhh... typing. It actually fits in (or not) with a larger project on terrorism that I'm working on. If the OKC conspiracy theorists are indeed full of excrement, then I can drop this line of inquiry.

Right now, I doubt the offical story. My 'axis of doubt' as it were, runs through three main nodes: 1) Terry Nichols' trips to the Phillipenes 2) Eyewitness accounts of other people - Middle Eastern mostly - on and fleeing the scene shortly before and after 3) the bomb. So let us turn to Partin.

Oh, dear, why yes I have seen Partins analysis. Partin is a fruit. Partin has sent 'analysies' to 'congress' (anybody can send anything they want to congress) and to the media saying that TWA 800 was caused by a missile and pushing for half a dozen other conspiracy theories.

I googled him, like you suggested. I found lots of OKC stuff and only one hit on TWA 800. (Though I didn't spend much time on it.) Could you point me toward the other conspiracy theories he touts?

In any case, he may well be a fruit. I have already explained my tolerance of sources. I don't care if he thinks there's an international communist conspiracy to sap and impurify his precious bodily fluids. The only thing I care about is his arithmetic. (report link)

to to fail a majoy support column, all you have to do is pulverise enough of the concrete

Yes, Partin explains this. In order to pulverise concrete you need ~3,500 lbs. per sq. i. Even when using professionally installed charges in demolition, the steel structure isn't destroyed: "The rods are inertially confined during the explosion and survive basically intact because of their much higher yield strength and plasticity."

And an ANFO blast wave is perfectly suited to pulverizing brittle substances such as concrete

Partin's problem with the ANFO is the distance. Partin maintains that an ANFO bomb could not have pulverized the concrete at that distance.

First, blast through air is a very inefficient energy coupling mechanism against heavily reinforced concrete beams and columns.

Second, blast damage potential initially falls off more rapidly than an inverse function of the distance cubed. That is why in conventional weapons development, one seeks accuracy over yield for hard targets.

He mentions cutting charges as an alternative explaination because of the photographic evidence. Unfortunately, I haven't been able to find an online copy of his report with working links to the photos.

When a reinforced concrete structure is damaged through air shock coupling and the pressure is below the compressive yield strength of the concrete, the failure mode is generally compressive structural fracture on one side and tensile fracture on the other, both characterized by cracks and rough fracture surfaces. Such a surface texture is very different from the relatively smooth granular surface resulting from contact explosives..... (skipping a lot)....A careful examination of photos showing the "A" row columns and the large header from the third floor reveals absolutely no air blast shock wave fracture, which is consistent with the pressure falloff with distance from the truck bomb.....(skipping a lot)....Tab 8 shows the localized demolition damage at the juncture of column A7 and the header. The same telltale demolition charge evidence is clear. The straight edge of the decorative grove at the juncture can be seen on both the column and the header.

AFTER the prosecution, McVeigh admitted that he used Nitromethane, confiming the eyewitnesses.

We must be fair to Partin here. His report is dated 30 July 1995, before the Nitromethane aspect came to light. At the time, the assumption was a 4,800 straight ANFO bomb with, I believe, a PETN detonator.

There is a published study somewhere saying that the blast effects were inconsistent with a low-octane ANFO explosion from an assumed amount of ordinance. But what is not pointed out is that if you either increase the amount of ordinance or use a higher-octane fuel, the blast effects are entirely consistent.

If you could find that study, that would be fantastic. In the end, I'd like to do some number crunching myself, but I'm allergic to math. :-)

Also, look at the crater size.... Also, how could it have thrown the Ryder truck axel as far as it did....

I'm afraid you're not putting yourself "inside" the conspiracy theorist's construct here. You've got to think like one to understand their arguments. In the view of the conspiracy theorist, the gov't is surpressing information about the nature of the Murrah building collapse - the composition and/or location of the bomb (or bombs).

If you accept this premise, that the gov't is surpressing bomb information, it is not a wide leap to active government disinformation. That is, making up stuff to corroborate thier story, in the press and in a court of law. And, given what we know now about the FBI crime lab, that's not too far fetched.

Do you propose that those few feet magically dispersed a blast wave capable of rending steel into shrapnal?

That is the heart of Partin's analysis. Air could not have transmitted that blast wave far enough.

The maximum possible yield from 4800 pounds of ammonium nitrate would be obtained if it were in a compressed sphere and detonated from the center. That would produce a 4.4 foot diameter sphere of detonation products at about 500,000 pounds per square inch. By the time the blast wave hits the closest column, the pressure would have fallen off to about 375 pounds per square inch. That would be far below the 3500 pound compressive yield strength of the concrete. Any column or beam failure from the truck bomb would therefore have been from blast wave structural loading and not from any wave of deformation in the concrete

He also says that if the blast wave from the truck failed column 'B3', there were other columns that should have failed, too, specifically 'B4' and 'B5'.

From the potential damage contours on Tab 3, and assuming the single truck bomb, the pressure and impulse for collapsed columns B4, B5 and A7 are all in the 25 to 35 pounds per square inch region. However, the much smaller and closer columns, B4 and B5, are still standing, while the much larger column A7 is down. Column B3 is down with 42 percent less pressure and impulse than columns B4. These facts are sufficient reason to know that columns B3 and A7 had demolition charges on them. Moreover, there is not sufficient blast impulse at that range to collapse any of the three. In fact, columns B2, B4 and Bs all have the sheet rock and furring strip finish still intact on the second and third floors except where damaged by falling debris.

I'd like to see a specific refutation of Partin's arithmetic.