“They’re up to no good”

“Them kids are still up there goofing around,” said the engineer on two SD40-E helper-units on Norfolk Southern’s railroad radio.
Every Saturday yr fthfil srvnt switches off the classical-music station I usually listen to, and I fire up this ‘pyooter.
I get the railroad radio feed out of Altoona, PA, over the Internet.
I switch because I can’t stand the programming, particularly a complete opera.
350-pound stringy-haired blondes screaming Ride of the Valkyries at the top of their lungs.
Stabbings and murders and suicides off castle parapets, all to sung dialog.
When do you ever hear sung dialog in common speech?
“Uh-oh..... They goosed her again.”
“What are they doing up there?” the railroad’s dispatcher asked.
“Flashing,” the engineer said.
“What’s that?”
“Exposing themselves.”
“I’ll turn it in,” the dispatcher said. “Can you provide a description?”
At this point I’ll let you, dear reader, fill in the blanks.
Sometimes it’s hard to keep a straight face.
“They’re up to no good, I tell ya.”
Where have I heard that before?
I wasn’t flashing, but was guilty of an attitude-rap.
Long ago I was called before the Dean-o at my evangelical college, not for drinking, but for wearing tight pants a la Rolling Stones.
They threatened to can me, but didn’t. I wasn’t pigging out on liquor; the beer-drinkers were in deepest do-do.
Amazingly we all graduated and got our degree.
So I wonder about those ne’er-do-wells at the railroad’s crossing of Allegheny Mountain near Altoona.
Do they get arrested? If so what’s the charge?
A flashing-rap?