he “bumper movement” was used by Alpina in the 50s. Today, it is extremely rare – if not virtually impossible – to find. It is a movement with an oscillating weight that instead of turning 360° like a contemporary rotor, turns 120°.

On both sides of its course, a small spring serves to send the mass back in the opposite direction and facilitate the winding of the movement. The concept was simple and effective but gradually phased out in favour of the 360° rotor, becoming a rare movement sought-after by collectors.

Now, Alpina has drawn inspiration from this unusual winding in developing its sixth Manufacture movement. It beats within the new Startimer Pilot Heritage Manufacture.

Known as the AL-709, the movement is a contemporary, accurate and robust creation that incorporates the hallmarks of its predecessor, the “bumper”. This is because Alpina has designed its key component, the rotor, in the style of that from the Fifties.

The oscillating weight from the Startimer Pilot Heritage Manufacture and that of the vintage "bumper” are related, sharing the same geometry and the same inspiration, but for two details: the vintage version rotates 120°, while the new one rotates 330°. Secondly, the traditionally shaped springs originally used have been replaced by a blade for greater rotation. The AL-709 calibre can also be admired in all its glory through the open case back.

To celebrate its new movement, Alpina has selected the cushion-shaped case from its Startimer Pilot Heritage collection. It is the perfect combination of a circle in a square with delicately rounded edges, emphasised by a case middle that alternates between polished and satin-brushed surfaces.

The AL-709 calibre hugs each contour, as a mark of respect for watchmaking tradition. Previously, the calibre and the case had to have exactly the same profile (in the tradition of so-called “form” movements). The beating heart of the watch becomes one with the delicate cushion that follows the contour of the wrist. To complete the vintage look, Alpina has given the Startimer Pilot Heritage Manufacture a dial with an iconic design harking back to the pilots watches also created by the brand in the 50s.

Two versions of the Startimer Pilot Heritage Manufacture are coming out to honour the modern renaissance of the “bumper”. Collectors will be pleased to know that each is limited to just 188 pieces.

Sharing the same dimensions (42 mm), they come in a yellow gold-plated and a steel version. Three matching hands are enhanced by a central red line for a sporty feel. To maintain the flow of the case, the crown has been placed at 4 o’clock, in the vanishing line of the caseband. With a power reserve of 38 hours, both are worn on a brown calfskin strap with off-white topstitching.