Audemars Piguet 26735ST Royal Oak 50th Anniversary Flying Tourbillon Openworked

For me, this is the trilogy of everything that Audemars does so so well. 

The Royal Oak model line is a watch design icon, the flying tourbillon is a mechanism for increased accuracy, and the openworked dial is executed to one of the highest standards in the industry. 

It is peak AP. 

At 41mm at the diagonal and 10.6mm tall, its at home on pretty much any sized wrist either under a shirt cuff or with jeans and a T. 

The dial here is really something special as its immediately noticeable symmetry sets it apart from the “standard” double balance wheel openworked. 

It is further elevated by being pure slate grey throughout which gives a depth to the skeletonisation which can sometimes be missed on darker openworked dials as there is less contrast between the dial and its void spaces. The pale silvery grey was a perfect choice here.

The bottom part of the dial reveals its star of the show - the flying tourbillon. Named “flying” because it is supported only from below and minus any upper bridge to obscure the spectacle. 

The tourbillon - derived from the French word for “Whirlwind” - exists for two reasons - 

  1. To counteract gravity which could potentially affect timekeeping.
    On a fixed plane balance wheel and escapement found on a “regular” watch, positional variation and gravity can create drag, which in turn can affect accuracy.
    A tourbillon is a balance wheel in a freely spinning cage which constantly changes direction so is theoretically unlikely to suffer from positional deviations. 
  2. To look nuts. 

Powering the watch is the self-winding 27 jewelled caliber 2972 which can be viewed in all its glory through the sapphire caseback.

The 50th anniversary rotor for this piece really doesn’t obscure the view thanks to being equally openworked. 

The case and bracelet are finished to the exacting standards that we come to both love and expect of AP.
There isn’t a grain out of place on the brushed finish and the mirror polished parts add just enough shine to really bring out the perfectly angled case lines and shapes.

There is nothing I can add about the Royal Oak case and bracelet, for me it is unsurpassed, just as it was always designed to be 50+ years ago.