The legendary aviator wristwatch Mark XI by IWC may rightly be called a “cult watch”. It was produced in the period from 1948 until the early eighties. Each watch was checked on its accuracy in a 44-day test program at temperatures between minus five and plus 46 degrees Celsius and at five positions.

Not only the pilots of the Air Force, but also civilian airline pilots were familiar with this timepiece. When the Royal Air Force began with the exemption of the Mark XI in the mid eighties, one could still acquire it at 100 to 200 dollars. Today it is a coveted collector's item, which is traded at about several thousand dollars and, unfortunately, is difficult to obtain.

The replacement, Mark XII, was introduced in 1993 as a civilian model with similar styling but an automatic movement.

• Die Pilot's watches von IWC; Authors Christian Pfeiffer-Belli, Rüdiger Bucher; ISBN 3871880701 (engl. version ISBN 387188068X )
• IWC-Uhren. Die "Schaffhauser" und ihre Geschichte; Author Reinhard Meis; ISBN 3853782531
• IWC, International Watch Co. Schaffhausen, Engl. ed.; Authors Hans-F. Tölke, Jürgen King; ISBN 3906500152
• Die Grande Complication von IWC; Author Manfred Fritz von Edition Stemmle, Kilchb.; ISBN 3908162076
• Armbanduhren-Spezial IWC - Geschichte, Design, Technik; Author Jörg M. Mehltretter; ISBN 3898800458
• IWC - Die Noblen aus der Schweiz. Handbuch für den Uhrensammler; Author Jörg M. Mehltretter; ISBN 3898802272
• IWC, International Watch Co. Schaffhausen, Luxusausg. Engl. Ed.; Authors Hans-F. Tölke, Jürgen King ISBN 3906500160
• Die Fliegeruhren von IWC. Deutsche Ausgabe - version IWC; Authors Rüdiger Bucher, Christian Pfeiffer-Belli; ISBN 387188071X