February 9, 2023
Front of IWC Big Pilot's Heritage 55

At SIHH2016,IWC unveiled its new Big Pilot’s watch-Heritage Watch 55. What makes it attractive is the diameter,it seems a big boy.

The Heritage Watch 55 it’s a 55 mm watch, which according to IWC was the diameter of the original 52 caliber TSC made for the German Air Force in 1940. Exactly 1,000 of the original watches were made, according to the lot notes from Christie’s that accompanied the sale of one last year. It is the biggest wristwatch ever built by IWC, with a case diameter of 55 mm., a height of 16.5 mm. and a weight of 183 grams. IWC Big Pilot's Heritage 55  This modern interpretation is fitted with the IWC caliber 98300, also known as the “Jones Caliber” as it duplicates many of the features of an early IWC pocket watch movement designed under the direction of IWC founder Florentine Ariosto Jones. The caliber 98300 has a distinctive, very long regulator index and it beats quite slowly by modern standards, at 18,000 vph, with a 48-hour power reserve. It’s a very fine movement, albeit very old-school in just about every respect hand-wound, with a Breguet overcoil balance spring.Front of IWC Big Pilot's Heritage 55
The Heritage Watch 55 is slightly thinner than the original, at 13.5 mm, and the case is titanium which cuts the weight to “less than 150 grams” according to IWC. I can say, having had a chance to preview this watch in Switzerland recently, that despite the size it’s wearable, though of course at 55 mm it’s not likely to be anyone’s everyday timepiece. The Heritage 55 also duplicates the antimagnetic features of the original, with a soft iron inner case. Incidentally, such iron cases are often referred to as Faraday cages in the horological press; strictly speaking this isn’t the case.Side of IWC Big Pilot's Heritage 55

A Faraday cage protects against electrical fields and radio frequency interference, whereas a soft iron inner case and dial work, basically, by providing a path of least resistance for magnetic field lines.