Omega Watch Co., Swiss, Movement No. 10826411, Cal. 27 CHRO C12 T2 PC, Ref. 174-1 2451, 35 mm, circa 1947

An aviator's extremely rare chronograph of the "Fédération Aéronautique Internationale" with red markings
Case: steel, screw back with engraving: "F.A.I. 049" (The World Air Sports Federation), pusher for chronograph at "2" and "4", "Omega" buckle. Dial: silvered, luminous Arabic numerals, engine-turned subsidiary dials, red auxiliary seconds, red 30 min. and 12h counter, signed in red, luminous alpha hands. Movm.: 3/4 plate movement, rhodium-plated, ground, signed, 17 jewels, finely ground chronograph steel parts, ratchet wheel, Glucydur screw balance, incabloc shock protection for balance.

Fédération Aéronautique Internationale
The Fédération Aéronautique Internationale, FAI – The World Air Sports Federation, is the world governing body for air sports, aeronautics and astronautics world records. Its head office is in Lausanne, Switzerland. This includes man-carrying aerospace vehicles from balloons to spacecraft, and unmanned aerial vehicles (such as model aircraft and UAVs). It was founded on 14 October 1905.
Source: https://en.wikipedia.org/wiki/F%C3%A9d%C3%A9ratio​n_A%C3%A9ronautique_Internat​ionale, as of 09/02/2015.