Modern read/write heads hover over platters at a distance equal to about one-tenth the thickness of a human hair. Therefore, any pit or scratch in a drives platter's surface has the potential to damage the read/write head and render the drive useless, according to Cane.
"It's like taking a jet airplane on the ground and at full speed going over a pot hole. You're going to do damage to the head by going over the pot hole," he said. "And, every time you go across that part of the platter, you're going to chew up the heads."
If Lanza were technically proficient, Cane said, he could have also overwritten his drive, which means the zeros would have becomes ones and ones would have become zeros, essentially wiping the drive of any retrievable data.
Rogers disagreed that if a drive's platters are broken, scratched or punctured data cannot be retrieved. As long as the some areas of the platter's surface are intact, there are electromagnetic devices that can read the data and transfer it to a new hard drive, he said.
Many of the devices for reading damaged drives come from Soviet-era Russia, when intelligence agencies were attempting to recover top secret information from electronic media that had been intentionally damaged.
"As long as it can read the magnetic flux even on a portion of the drive, there is a possibility to recover that data," Rogers said.
Sign up for Computerworld eNewsletters.