I think the Grand Coulee dam is over 450' thick of reinforced concrete at its base, and over 30' of the same at the top. The gummint itself acknowledges it's unclear that a non-ballistic, large-yield nuclear warhead could breach it. Same with Hoover dam (657' thick at base, 50' at top, arched). Conventional explosives, placed casually...well, it makes for a great tour, I'm sure.

The government posted several reports in the 70's looking specifically at geologic and inflicted vulnerabilities of several dams in the US inventory. Copies were located in the MSU campus library in Bozeman. Perhaps things have changed since then...I have my doubts. The reports said essentially that it was unclear how any single event at that time could breach either Grand Coulee dam, Hoover dam, or any of a number of others.

It's a case of low possibility/high impact risks that humans have the hardest time evaluating rationally.

I'll leave it to the curious to imagine whether a 172 loaded with 50 gallons of avgas, prel, and stupidity could make more than an unfortunate smear that would eventually wear off in the rain.

If I remember correctly, Barnes Wallaces' Dam Buster bombs in WWII contained something like 20,000lbs. of TNT. Seems like a 172 loaded with anything would hardly be a threat.

Stickman wrote:If I remember correctly, Barnes Wallaces' Dam Buster bombs in WWII contained something like 20,000lbs. of TNT. Seems like a 172 loaded with anything would hardly be a threat.

Exactly. The gravity dam targets for Wallis' project were chosen for a reason: they were not reinforced concrete. Very few dams back then were. A 172 might merely create a spectacle.

The only reason I get uppity about this is the tendency for regulations to become silly where airplanes are concerned. After 9-11, folks may recall there was a proposal to close the airspace over all large public event centers in the US- permanently. Football games, etc. School events were even mentioned. And we still have the TSA.

Just a fuss about nothing....
Typical of America today.