Hamilton in Zero Gravity


It has been demonstrated that accelerations from 0G to 10G have an impact on the human body, and that athletes like Nicolas Ivanoff, capable of withstanding accelerations of this order without an anti-G suit, are rare. However, there have been no studies on the impact these accelerations may have on the precision of that indispensable object, dearly beloved of pilots: the mechanical watch.

Hamilton, whose passion for aviation is allied with a passion for innovation, therefore decided to measure the precision of their mechanical watch movements when subjected to various accelerations, participating in the research initiated by ETA at the beginning of 2013. From 11 to 21 May 2015 a first test and validation phase for the measuring equipment marked the start of the study covering the range 0G to 2G.

From 5 to 16 October, at Mérignac in the French region of Aquitaine, this campaign for the testing of Hamilton watches will take place on board the A310 ZERO-G of Novespace in partnership with ETA, and will be realised in the context of the scientific campaigns conducted by the CNES (the French National Centre for Space Studies). A total measuring time of 30 minutes in zero gravity (three flights, each including a ten minute period of zero gravity) will ensure reliable results.

Theoretical models exist for calculating the effects of gravity on precision chronometry in absolute terms: disequilibrium of the spiral, disequilibrium of the balance wheel, friction on the pivots of the balance wheel due to the weight of the balance wheel, compensation for play in the pivots. This campaign will be the first to compare the theory with experimental data gathered under conditions of a total absence of gravity (0 G).

The conclusions will be applied to the development and optimisation of the performance of mechanical watches for two different user categories: users on the ground with weak gravitational variations (1G ±1) and users specifically engaging in extreme sports.