One of the most important stories in the perpetual calendar legendarium begins in 1985, with Kurt Klaus’ introduction of the Da Vinci ref. IWC3750. It was by no means the first perpetual calendar wristwatch, but it was certainly innovative with its pre-programmed mechanism that allowed users to adjust the mechanism by simply turning the crown. No hidden case pushers or easily misplaced corrector pins, here. While I certainly don’t have the horological credibility to criticise Klaus’ creation, it did come with some caveats when compared to the traditional QP mechanisms. The main one reared its head in case you accidentally went too far forward when adjusting the calendar. To resolve it, you’d have to wait for the power reserve to deplete and the days to catch up, as there was no going backwards. The all-new Big Pilot’s Watch Perpetual Calendar ProSet trio includes resolves that very issue, as it now allows its wearers to adjust the calendar mechanism forwards and backwards, which required a complete redesign of the movement according to the brand.
What is it?
The perpetual calendar modules in the Portugieser QP (L), and new ProSet and its LIGA wheels (R)
IWC is proud of the fact that the dial design is left essentially unchanged compared to the ProSet’s predecessors, but the same cannot be said for what’s under the hood. The latest generation of the Kurt Klaus system comprised some 80 components and added only 1.5mm to the overall height of the watch. Looking at the two side-by-side, the differences are clear, as are the advancements in technology. IWC is especially proud of its extensive use of LIGA technology, which allows for the manufacturing of very small, but very intricate components – those special teeth are a great example of that. The most complicated component is the new, multi-level programme wheel (on the photo above, it’s about to be placed into the movement on the right-hand side), I’ll let IWC’s explanation do the heavy lifting here, as it’s more clear and concise than I could make it: “In shorter months, its unique shape triggers the extension of flexible fingers. When these fingers are extended, the 24-hour wheel engages not one but several teeth during its nightly switching sequence, ensuring that the calendar advances directly to the 1st of the next month.”
All of this is built on top of the 82665 calibre, part of the 82XXX family that is often used as a base for complication modules and has previously featured across the entire IWC line-up. The latest variant now sports a ceramic automatic wheel and clicks for vastly reduced wear, the hairspring is in silicon, while the Pellaton winding remains, topping up a 60-hour power reserve.
The ProSet calibre debuts in three new Big Pilot watches – a green and gold variant and two Le Petit Prince models in steel and ceramic, the latter of which I spent the most time with. Across the three materials, there are slight differences in size. The white ceramic model is largest at 42.9mm across and 14.3mm thick, while the steel and gold ProSets drop down to 42mm in diameter and 14mm in height, though the differences on-wrist are barely noticeable.
First impressions
As it’s the model I got to photograph – and coincidentally my favourite (funny how that happens, hey?) – I’ll spend the most time talking about the white ceramic-cased Le Petit Prince. If you’ve previously handled or are familiar with IWC’s Big Pilot Perpetual Calendar recipe, you won’t come across anything that’s not familiar here, though there are some changes that are of note, and for the better. Owing to the new perpetual calendar module, the new ProSets are the most compact perpetual calendar models in the Big Pilot’s Watch collection, dropping down from the imposing 46mm+ size to a much more manageable 43mm. Despite this reduction in size, the dial layout is in my opinion more pleasing than the larger, 52XXX calibre-equipped models. The ProSet gained the four-digit year indicator in the bottom left corner previously reserved only for the largest IWC perpetual calendars, and the sub-dials have been arranged so that they do not cut off any of the numerals.
Is it a watch that’s going to easily slip under cuffs? Of course not – but let’s be serious here, it’s in the name. Especially when cased in white ceramic, the new ProSet is about the smallest expression of the Big Pilot’s Watch identity I’d like to see, and when looked at in context of its proportions, it works really well. That said, and thinking of those who prefer to stick closer to the 40mm range whether by way of personal preference or girth of appendage, I’d really love to see IWC extend the use of the new ProSet module into smaller perpetual calendar watches. New 40mm Portugieser QP, maybe?
While it has gone through numerous iterations over the years, IWC’s 8000 series calibres rely on an architecture first presented in 2005, and the beginnings of the brand’s in-house production developments. In fact, the 8000 itself takes cues from the wheel train of the Valjoux 7765 that is as ancient as it is ubiquitous. This isn’t necessarily a negative, as IWC has upgraded it enough over the years to justify not having to develop an all-new calibre from scratch, and the latest 82665 and its nickel-phosphorus, ceramic, and silicon components does have the chops to remain relevant, especially when paired with the ProSet module. Sure, it doesn’t allow the same level of control as AP’s cal. 7138 (all functions individually adjustable through the crown), but it is also a third of the price, which is more than good enough for me.
