Few manufactures can claim as storied a history as IWC, and few movements have withstood the test of time as well as their Caliber 89. IWC’s Caliber 89 was developed in 1946 amidst the aftermath of World War II, and the rubble of their previously bombed factory. The development of the Caliber 89 signified a rebirth for IWC and paved their way for years to come.
The British Ministry of Defense needed a new timepiece for their military, prompting them to develop requirements for a watch to replace their ATP (Army Trade Pattern) branded watches. The replacement would have more stringent requirements and would come with the WWW (Watch, Wrist, Waterproof) mark on the caseback. Although a “WWW” piece, IWC issued watches are generally referred to as Mark X or XI by collectors, depending on the iteration. the Mark X came first (obviously), and it carried the Caliber 83, and Mark XI carried the 89. A dozen manufactures supplied WWW timepieces to the British military; however, it was IWC’s manually wound Caliber 89 that has truly withstood the test of time. In fact, the Mark XI was issued for over 30 years.
The movement was developed by IWC’s Albert Pellaton, and was on the forefront of technology for the time, using the newest and most robust materials (although still predating the forthcoming automatic movements). There was nothing particularly complicated about the movement; however, it is a simple, reliable, and accurate 3-hand movement. At first glance, the movement seems relatively basic and does not feature a luxurious fit and finish, but it does exactly what it’s supposed to do. Mechanically, it is extremely well made with an attention to detail not seen amongst its peers of the era. This is why you’ll still see this on the wrists of collectors almost 70 years after its creation.
Mk XI, courtesy Watch Talk Forum member frodostar
The aforementioned Mk XI was the showcase for the Caliber 89, and predecessor to Schaffhausen’s long line of pilot’s and military watches. The central seconds hand was a necessity to enable a Pilot’s quick visual recognition, and the Mk XI’s soft iron inner case protected the movement from magnetic fields. Unsurprisingly, the finished product would become the standard for military-grade timepieces. Also noteworthy is that a movement this outstanding was also mass produced, which was not the norm in the 1940’s, especially for a watch as refined, and resistant to the elements.
IWC continues the tradition and legacy of the Caliber 89. Its influence can be directly attributed to their fantastic Caliber 50000 movement we have today. That caliber family has nearly identical, albeit modern, versions of the 89’s balance, pallet, and escape wheel. IWC also has a line of in-house calibers called the 89000 family, which is an obvious tip-of-the-cap to the Caliber 89.
There are many vintage British Military watches carrying the WWW designation to choose from, but in our book, they didn’t come any finer, or horologically significant than those from IWC. A Caliber 89-powered IWC would be a great addition to anyone’s collection, be it a Mark XI, or any number of civilian watches carrying the movement. The Caliber 89 has all the history, toughness, and accuracy you could want that still holds up today, and the IWC Caliber 89 most certainly deserves to be in the Wound For Life Hall of Fame.
Caliber 89
Featured, and final image courtesy Timezone.com
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