An Interview With The Guy Behind The Oris Big Crown ProPilot X Calibre 115

Oris’s latest watch powered by an in-house developed calibre is a landmark design. The skeletonised Calibre 115 movement opens up the 10-day power reserve and non-linear power reserve indicator to reveal how they work. It’s a contemporary take on luxury that highlights the eternal value of a beautifully crafted Swiss Made mechanical watch. Oris’s Senior Product Design Engineer, Lukas Bühlmann was telling us how everything came together.

What was the design brief behind the Big Crown ProPilot X Calibre 115?
Ultimately, the brief was to propel Oris Aviation watches into the next generation. We made pilot’s watches for American servicemen in the Second World War. But what does a contemporary, luxury Oris
pilot’s watch look like?

What were the biggest obstacles to delivering that brief?
One of the hardest things was figuring out how to maintain the balance between the formal language of the case and the movement. In other words, how do you design a modern watch that is not a fashion watch? We wanted to create something contemporary that would retain its relevance as fashions change.

Where did you look for inspiration?
Aviation and architecture. The idea behind the watch started with the movement, and we gave this a strong architectural look. The skeletonised barrel draws your eye first and then the bridges, and then you start seeing the detail in the wheels.The case is more like a stealth plane. There’s an exciting interplay between the movement and the static elements.
There’s a futuristic quality to the design – is that deliberate?
I wouldn’t call it futuristic, but it is a future-driven design. Oris has a long pilot’s watch history and you can see that in the design, which is important. It also shows Oris’s competence, and the long-term value of a beautifully designed and manufactured mechanical object.

Do you think of this as a pilot’s watch?
It’s certainly not a conventional pilot’s watch. For example, this is the first Oris pilot’s watch without any numerals on the dial. But the aviation DNA is still there in the details. We used titanium for the case, for example, because it’s very light. What really makes this a pilot’s watch is its technical look. Technology is the driving force behind aviation today.

What design considerations are there with a skeletonised watch?
First and foremost is technical feasibility. This is a designer’s constant companion during the design process. The design and the functionality have to work together. Furthermore, you have to think on several levels at the same time, so that when all the components come together, you get the design you set out to create. Overall, because of these considerations, the job takes longer, too.

Sometimes, those considerations must create problems?
Yes, of course. Sometimes you want to design something one way, but you quickly realise that it’s not technically feasible. It’s about adapting. The better you understand the design philosophy, the quicker you’ll find solutions.

What does this watch say about Oris’s take on luxury?
The truth is that for Oris, luxury is about being able to go your own way. That’s why it’s our strapline. In practice, that means we design watches for people who ask questions and want to experience life and cultures. Our watches become faithful companions for life’s adventures. Wherever you go, your Oris watch will go with you.

What makes this a good design?
The small details – every case facet, the way the bracelet integrates into the case, the decision to drop the numerals, the crown protection, the bridges, the turbine blade bezel, and so on. It’s the way these come together so that you don’t see them as small details, you see them as part of a whole that makes this design unique.

Do you work to the design mantra that ‘form follows function’?
A watch should be meaningful and feature useful complications, and the appearance of the watch should reflect what it does. But form follows function is too rigid. Again, if ‘Go your own way’ is the philosophy, you can’t be bound by one set of rules..

What does the Big Crown ProPilot X Calibre 115 say about Oris design?
I think it says two things. It says we’re not afraid to push boundaries. And also that we’re good at combining talents. A team of 10 people were involved in the design of the movement, case and bracelet. Like the watch, many small parts came together to create something heroic. We’re all really proud of the result.

In detail

Case Multi-piece titanium case
Size 44.00 mm (1.732 inches)
Dial Skeletonised
Luminous material Hands and indices filled with Super-LumiNova®
Top glass Sapphire, domed on both sides, double-sided anti-reflective coating
Case back Titanium, screwed, see-through sapphire glass
Operating devices Titanium screw-in security crown
Strap/bracelet Multi-piece titanium bracelet with ‘lift’ clasp; black leather strap with titanium ‘lift’ clasp
Water resistance 10 bar (100 m)




Number Calibre 115 (skeletonised)
Functions Centre hands for hours and minutes, small seconds between 7 and 8 o’clock, non-linear power reserve indicator at 3 o’clock, fine timing and stop-second devices
Winding Hand-wound
Power reserve 240 hours