Some times backups fail

Doesn't only happen in the tech world....

The NYPD staged a daring nighttime rescue that lasted into early this morning to free 69 people who were stranded nearly 250 feet above the East River on the Roosevelt Island tram.

Both of the tramway's cars stopped cold at about 5:20 p.m. after the main source of electricity and a backup generator inexplicably failed, authorities said.