Phencyclidine, also known as angel dust, is a dissociative hallucinogenic drug.
Zappa about PCP
From the "Other Options" section of the "Practical Conservatism" chapter of The Real Frank Zappa Book:
"What if a kinder, gentler CIA chose to produce a low-cost 'designer drug' with special 'social engineering characteristics,' and mount yet another covert civilian test for profit, arranging for this New Buzz to drive Traditional Flavors out of the marketplace? It worked with LSD. (And doesn't PCP - makes you crazy; takes five guys to hold you down; etc. - have a sort of 'militarily-useful' aura about it?)
From Frank Zappa, 82/03:
"What kind of stuff can we expect? Can you describe any of it?
Well, I'll tell you what we've already recorded. A lot of stuff with [One-time Mother] Roy Estrada. A song called "Truck Driver Divorce" which will probably be the end of country and western music. It's like country music on PCP."
From Frank Zappa 89-12:
"What do you think about how drugs are integrating into society and where they're coming from?
Think of it this way – you know where pot comes from, right? It comes from the ground. Did it ever occur to you that designer drugs are not things that just come springing out of the ground? They're not natural. Some scientist had to build them. The construction of these designer drugs requires sophisticated equipment. Now the guy who's growing marijuana, or the cocaine rancher in South America, he's not a scientist. He's a businessman-farmer combination. All these weird new chemicals come from professional places. It probably wasn't just a little hobby that started in the laboratory because you don't get to use the laboratory whenever you want. Somebody said, "Make me this. Make me XTC, make me PCP, make me LSD. Here is your contract, here is the money, hire the people, invent this drug. Deliver it to me on this date. If you can, we will then do experiments." The experiments to find out what these chemicals will do to human beings can't be conducted on goats and sheep. You have to do the experiments on people. Unfortunately, in America you have a society that contains a large number of people who are willing to take part in these experiments. They actually pay to take these chemicals that have been created for some unknown purpose. I think that before you stick a chemical in your body, you should think about where it came from and who's really getting the benefit."