Summary A Boeing 747 cargo jet reached high supersonic speeds during an emergency descent in 1991. The crew noticed a rapid descent and an unprecedented 90-degree tilt in the aircraft. The 747 reached speeds beyond Mach 0.
92, possibly up to Mach 1.25, during the emergency. Did you know that a cargo-carrying Boeing 747 once inadvertently flew supersonically? Reports from 1991 suggest that the aircraft reached a speed of Mach 1.
25 while rapidly descending due to a malfunction. While this was never confirmed, this could be the fastest that a commercial Queen of the Skies has ever flown. Sudden drop According to This Day In Aviation , December 12th marks the date of a notable event in history.
We all know that the Concorde and the Tupolev Tu-144 were the only commercial aircraft designed to reach supersonic speeds. But what if a Boeing 747 did the same? An incident in 1991 could have seen it happen. Get the latest aviation news straight to your inbox: Sign up for our newsletters today ! The story begins on an Evergreen International Airlines Boeing 747-100F, registered as N475EV.
The aircraft had recently been converted to a freighter for the use of charter operator Evergreen. On December 12th, 1991, the plane was flying from New York John F. Kennedy International Airport (JFK) to Tokyo, stopping in Anchorage International Airport (ANC), when the crew noticed a failure warning on the inertial navigation system (INS).
The flight was carrying six crew and cruising at 31,000ft over .