IWC has made a habit of launching a new collection at the SIHH salon every January, followed by single model launches, often limited editions, throughout the year. While the Pilot’s collection received the SIHH treatment, the first individual model to get the special limited-edition treatment this year is the Ingenieur Perpetual Calendar Digital Date-Month; limited to 100 individually numbered pieces. The flagship of IWC’s Ingenieur family is presented for the first time with a titanium case. With this launch, IWC has added another feather to its selection of traditional watches with ‘digital’ displays.

IWC launched the ‘IWC Tribute to Pallweber’ collection, a few years ago, which consisted of three wristwatches and one pocket watch.

The standout mechanical feature of the collection was the date and month’ digital display’ which, in reality, comprised of oversized, easy to read numbers printed on rotating discs that were mechanically driven under the dial. The mechanism can account for the different lengths of each month, including leap days.

The latest Ingenieur has a case measuring 45 millimetres and is made of grade-5 titanium, widely used for making aerospace airframe and engine components because of its higher strength and hardness. The dial is slate coloured over which are the black hour and minute hands with luminescence. It has two arched windows at the top end of two sundials for the large ‘digital displays,’ one is at the 3 o’clock for the month and another at the 9 o’clock for the date. At 12 o’clock is a totalizer subdial with combined hour and minute counters. At 6 o’clock is the seconds subdial with a leap-year counter display.   

The IWC Ingenieur Perpetual Calendar Digital Date-Month

The date and month displays of the perpetual calendar are produced using four large discs. Two of them are for the date whereas one is for the single-digit and the other for the tens. Similarly, there are two discs for the month display. There is a smaller fifth disk to indicate the leap year. The date discs for the single-digit and tens advances daily. However, the quick-action switch siphons off a little energy every night when the date display moves forward. It stores this energy and then discharges it precisely at the end of the month or year when, in addition to the date and month disc, the leap year disc also needs to be advanced. The digital display dates back to the IWC Pallweber watches from 1884 that displayed the hours and minutes using digits. Despite the complexity, the mechanism can be easily set using the crown and will not require correction until 2100.

The IWC Ingenieur Perpetual Calendar Digital Date-Month (Back)

The IWC-manufactured 89801 calibre movement of the watch features a chronograph with flyback function. The automatic winding system builds up a power reserve of 68 hours and features a rotor made of solid 18-carat gold. The 89801 is a member of IWC’s 89000 Calibre Family. The first of which, the 89360 calibre was introduced in 2007 and became the first manufacture chronograph movement to be completely developed in Schaffhausen. In this movement, the hours and minutes are combined in a totalizer at 12 o’clock. This made it just as easy to read a stop time of 8 hours and 54 minutes as it was to check the current time. Further developments to the 89800 calibre eventually involved incorporating the big digital date and month display as used, for example, in the Portugieser Perpetual Calendar Digital Date-Month.

The strap is 22 mm black calfskin while the glass back is see-through sapphire. The watch is water resistant to 12 bar.