Environmental tests and test results for the chronographs are outlined in the attachment to this memorandum. The following major discrepancies were found during environmental testing:
a) Rolex - It stopped running on two occasions during the Relative Humidity Test and subsequently failed during High Temperature Test No. 1 when the sweep second hand warped and was binding against the other hands on the dial. No further tests were run with the Rolex chronographs.
b) Longines Wittnauer - The crystal warped and disengaged during the High Temperature Test. The same discrepancy occurred on a second Longines Wittnauer during Decompression Test No. 8. No further tests were run with Longines Wittnauer chronographs.
c) Omega - It gained 21 minutes during the Decompression Test and lost 15 minutes during the Acceleration Test. The luminescence on the dial was destroyed during testing. At the conclusion of all testing the Omega chronograph operated satisfactorily.
The results of operational evaluations by the astronauts show a unanimous preference for the Omega chronograph over the other two brands because of better accuracy, reliability, readability and ease of operation.