Testimonials aside, the Schaffhausen manufacturer, which has a long tradition of pilot watches, is pushing them so much in 2024 that it is thinking of building one that behind its rough and enormous appearance contains a movement with a gem of Haute Horlogerie.

It is called IWC Big Pilot’s Watch Constant-Force Tourbillon Edition “IWC Replica Racing” and inside a 46.2 mm case it houses a tourbillon with a refined constant force mechanism whose concept was born in the mists of time.

What is Constant Force?

In a mechanical watch all the power comes from the winding barrel. That there is one – or more to increase its autonomy, for various reasons ranging from the elasticity of the spring, which in its development is never uniform from start to finish, or due to the ineffectiveness of the gear system that transmits the energy, the force that reaches the escapement is never the same and this is a problem for running precision.

In essence, a constant force escapement is an escapement in which the impulse is given to the balance wheel via an intermediate spring. At the end of the impulse the spring starts a mechanism that puts everything back into position for the next impulse. In this way there is no risk of “energy drops”.

However, everyone has their own way of obtaining consistent strength. Let’s take a look at how IWC implemented it.

IWC Big Pilot’s Watch Constant-Force Tourbillon Edition “IWC Racing”

First of all it must be said that the 94800 caliber that powers this Big Pilot’s is nothing new for IWC. It is the same one mounted in 2013 by the Ingenieur Constant-Force Tourbillon 2013 which is a re-adaptation of the 94900 caliber that powered the Portuguese Sidérale Scafusia of 2011, the first IWC watch with a constant force tourbillon.

Limited to 15 pieces, this timepiece combines IWC’s constant-force tourbillon device with a matte black Ceratanium case and the simple yet recognizable design of the Big Pilot’s Watch.

IWC Constant Force

The IWC constant-force mechanism disconnects the escapement from the direct flow of energy from the barrels through the time train and transmits consistently uniform energy pulses to the escape wheel.

IWC claims that the presence of the tourbillon compensates for the negative influences of gravity on the oscillating system, but this is only partially true because any tourbillon will never be able to correct the errors generated in the different postures that a watch can assume.

It is right to recognize that Abraham-Louis Breguet, who invented the tourbillon well over two hundred years ago, had the ingenious ability to compensate for running errors when, at the time, the watch placed in his waistcoat was in an almost vertical position. Everything else is just speculation.

However, the constant force undoubtedly has the merit of ensuring that energy always arrives regularly at the tourbillon and therefore the amplitude of the escapement pulses are also isochronous, which is no small thing.

Clock

Although some may prefer the steel Big Pilot’s, closer to genuine aviator watches, this is the first Big Pilot in Ceratanium, a proprietary scratch-resistant alloy that is as light and robust as titanium and as scratch-resistant as ceramic.

The constant force tourbillon at 9 o’clock is undoubtedly the element that attracts attention on the dial of this IWC Big Pilot’s, which however also features a double indication of the moon phases for the northern and southern hemispheres.

The white numbers and yellow touches recall those of a dashboard, while the power reserve indication at 4 o’clock is reminiscent of a speedometer. The slotted structure on the outer ring of the dial is inspired by the air intakes of a Formula 1 engine.

Even the black rubber strap of what is currently the most complicated pilot’s watch in the world features a detail borrowed from the world of racing. The internal insert is in Alcantara, a synthetic microfibre often used for the seats and steering wheel covers of racing cars.