Quizz aux experts-connaisseurs d’OMEGA

Source : http://forums.watchuseek.com/showthread.php?t=132

Extrait :

Citation :

Gemini Program

In 1962, NASA decided to equip the astronauts of its future Gemini
programm with a highly accurate, legible, resistant and reliable wrist
chronograph.

Donald K. Slayton, head of the flight Crew Operations , took action
to select the chronographs :

For the purpose of comparison tests, NASA purchased chronographs
different brands from Corrigan’s, a large retailer in Houston, Texas
the following watches where purchased : Elgin, Benrus, Hamilton, Mido,
Piccard, Omega, Bulova, Rolex, Longine and Gruen. Of theses only 3
where selected for the comparative evaluation testing :

Longines, Omega and Rolex (Omega movement : Omega 321 , Rolex
movement : Valjoux 72 , Longines : Longines 13 ZN)

1965 first qualification program :

Model tested : probably 105.012 no documents found for the moment
to firmly state this , but for sure a Speedmaster equiped with Omega 321
caliber

High temperature: 48 hours at 71º C followed by 30 minutes at 93º C.
This under a pressure of 0,35atm and relative humidity not over 15%.

Low temperature: Four hours at -18º C.

Temperature-pressure: 0,000001atm and temperature raised to 71º C.
Temperature then lowered to -18º C in 45 minutes and again raised to 71º
C in 45 minutes. This cycle was repeated fifteen times.

Relative humidity: 240 hours in relatuve humidity of at least 95% and
at temperatures varying between 20º C and 71º C. The steam had
a pH value of between 6,5 and 7,5.

Oxygen atmosphere: Exposure to 100% oxygen atmosphere at a pressure
of 0,35atm and a temperature of 71º C for 48 hours.

Shock: Six 11 millisecond shocks of 40g each in six different directions.

Acceleration: Linear acceleration from 1g to 7,25g within 333 seconds.

Decompression: 90 minutes in a vaccum of 0 10-6 atm and a temperature
of 71º C and 30 minutes in the same vaccum but at a temperature of 93ºC.

High pressure: Exposure to 1,6atm for one hour.

Vibration: Three cycles of 30 minutes (lateral, horizontal and vertical),
the frequency varying from 5 to 2000cps and back to 5cps in 15 minutes.
Average acceleration per impulse 8,8g.

Acoustic noise: 130dB over a frequency range from 40 to 10000Hz
for 30 minutes

Results of the tests :

Omega Speedmaster : gained 21 minutes during decompression test and
lost 15 minutes during the acceleration test , the luminescence of the dial
was lost during the test

Rolex Daytona : stopped running on two occasions during the relative
humidity test and during the high pressure test when the sweep second
hand wraped and press against the other hands

Longine Wittnauer : Crystal warped and disengaged during the high
pressure test , same fault occured during the decompression test

Final conclusion : the Omega chronograph performmed satisfactorily

In 1965, NASA chose the Omega Speedmaster Professional as the official
chronograph for the space program.

With the first Gemini flight (GT3) with astronauts Grissom and Young,
the Speedmaster Professional became part of the standard equipment
issued to the astronauts. The watch was worn on the outside of
the pressure suit with the use of a large black velcro band.

The Speedmaster was worn during the first walk in space by an American,
Edward White, in 1965. Two speedmasters were worn by each Gemini
astronaut one set on mission time , the other one on GMT or Huston time.

Beaucoup plus de détails encore à l’adresse ci-dessus.