Gerry, I’d like to thank you for having kept the discussion reasonably well-focussed upon engineering and physics. I have had many very unpleasant exchanges with “9/11 Truthers” who leap about diverse points eg. as if lack of effective airport security had some relevance to building collapse rates etc., and they have insisted upon insinuating that I’m some sort of pro-war secret agent, repeatedly sniggering amongst themselves.
I am no such thing; I’m an anti-war activist since 2003 and now a member of Extinction Rebellion; I spent ten days last April camping on the Marble Arch traffic island, and for many years I was a volunteer helping Craig with this website. It gets really depressing when some self-appointed gang quip among themselves about how I must exult in the murder of innocents, just because I know when Newton’s laws haven’t actually been broken.