The Boeing 727 is a narrow-body, short range jet airliner.
The aircraft uses a low-wing, T-tail configuration. It has three engines mounted in the rear. The central engine gets its air through an S-duct with an opening at the base of the tailfin. The 727 is also known for its rear-mounted airstairs, which were famously used by the hijacker D. B. Cooper to escape from the aircraft.
First flying in 1963, the 727 saw its heyday in the 1970s and 80s. It was the most-produced jet airliner for over a decade, seeing service all over the world. The majority of 727s were retired by the 2000s, but some are still flying today.
- Wikipedia: Boeing 727