It's not D.B.'s.

The parachute that was thought to possibly have been used by D.B. Cooper during his escape from a hijacked 727.... was not one of the four parachutes provided. THe parachute that was found was made of silk. The parachute Cooper used was nylon.

The FBI, which at first responded Tuesday by saying the matter remained under investigation, late Tuesday afternoon confirmed that there was no connection between the parachute and Cooper.

Cossey, who sold parachutes at a skydiving operation in Issaquah in the 1970s, had provided the chutes Cooper used. He told The Columbian of Vancouver that the newly found chute "absolutely, for sure" could not have been one of the four that he provided.

"The D.B. Cooper parachute was made of nylon," he said. "This 1945 parachute was made of silk."
- Source

Oh well. Not that confirming it actually was D.B.'s parachute would have made much difference. The guy has never been found or even remotely heard from. None of his money has been accounted for, asides from a $5,000 bundle that was found in the '80s. Did Cooper actually survive to enjoy his ill-gotten fortune? Who knows. And does it really matter anyways?