The Da Vinci Perpetual Calendar Chronograph (Ref. IW392101/IW392103) is the first watch from IWC to combine the well-known mechanical chronograph with a perpetual moon phase display on a subdial in a new complication module. The moon phase is displayed by a disc, partly silver- or gold-plated, partly dark blue, which rotates to show the shadow of the earth and the waxing or waning moon below an aperture in the dial. In order to achieve this, IWC’s watchmakers had to design the in-house 89630 calibre that powers the perpetual calendar’s other functions: the date, month, day and four-digit year display.
The name of the Da Vinci Tourbillon Rétrograde Chronograph (Ref. IW393101) in 18-carat 5N gold alone reflects its unique status: an unusual combination of a classic tourbillon with a retrograde date and a sporty chronograph on a single dial. The further-developed 89360 chronograph calibre, the new IWC-manufactured 89900 calibre, permits down-to-the-second setting of what is known as the “hacking tourbillon” via a newly designed system of levers. The result is a technically sophisticated and optically balancedcomplication with a clear, uncluttered design. The wearer reads stopped hours and minutes off from a totalizer at the top of the dial, while a central seconds hand shows elapsed seconds. The flying tourbillon is positioned below at “6 o’clock” and, on the left-hand side, the gently curved arc of the retrograde date display almost visually connects one complication with the other. Apart from this, the pallet lever and escape wheel were manufactured with the use of diamond shell technology for the first time. This involves a diamond coating that reduces friction, thus generating a higher output of energy.