MAIN TRANSMISSION (NAVY AND COAST GUARD ONLY)

NAVAIR 17-15-50.3

TM 38-301-3

T.O. 33-1-37-3

CGTO 33-1-37-3

HH-52

MAIN TRANSMISSION (NAVY AND COAST GUARD ONLY)

JOAP ATOMIC EMISSION ROTRODE

Abnormal Trend

(PPM Increase

in 10 hrs)

Normal Range

0-76

0-20

0-26

Marginal Range

77-88

21-25

27-32

High Range

89-114

26-29

33-39

Abnormal

115+

30+

40+

Average Concentration Other Elements:

Copper is commonly manifest in low-time boxes as extremely thin, foil-like flakes of bright copper in the chip

detector, screen, and filters. It often shows up during the post run-in filter checks on green gearboxes.

Contamination of this requires a serviceability check to verify that it is benign, and will generally diminish

drastically within about 10 flight hours. Continue to be wary of any contamination in the form of granules or

chunks.

Contamination may also be detected during spectrometric analysis of gearbox oil, particularly in a high-time box,

and the copper level may exceed published limits. In that case, check the filters and perform a serviceability

check if necessary. Barring secondary indications, continue the gearbox in service and monitor gradual copper

increases.

Flash copper plating on planetary gears