Sample Interval Variation.

should be removed, placed in a clean sample bottle, and forwarded with oil sample to assist in

evaluation.

f. Prior to performing maintenance on enrolled components and immediately after

maintenance has been completed. The repairs and change of oil will establish a new pattern or

rate of part-wear. This includes repair, replacement, or installation of any time-change parts or

components enrolled in the AOAP.

g. Prior to a component removal, regardless of the reason for removal.

h. After engine overhaul/rework and at the completion of a test cell run, test track operation,

or functional check flight.

i. Prior to transfer of equipment or overseas deployment of the components.

j. Special samples should be very clearly marked "SPECIAL" and banded with red tape or

marked in some other conspicuous manner in order that they may be easily identified by the

laboratory and processed on a priority basis

k. Special samples will satisfy requirement for routine sampling and will begin a new oil

sampling interval schedule for the component. Care must be taken to assure the next scheduled

sample is taken without exceeding the allowable range guidelines specified in paragraph 6-4.

l. Laboratory requested sample shall be submitted upon request. Resamples are requested

either as a result of a sharp increase in the wear metal content in the lubricant or because of the

amount of dirt and/or sludge in the lubricant indicates the sample was not taken properly.

NOTE: When unprotected aircraft are exposed to rain or high humidity for prolonged periods, a

special sample may be sent for analysis at the discretion of the maintenance personnel.

6-4. Sample Interval Variation.

a. Appendices A and B prescribe the specific interval for each component. Samples should

be taken as near the prescribed interval as possible. Owing to the difficulty of sampling at the

precise interval, the following variation guidelines shall be used to plan when to sample:

Table 3 - Operating Hours

SAMPLING INTERVAL

ALLOWABLE RANGE

5 hours

4-6 hours

10 hours

8 - 12 hours

12 ½ hours

10 - 15 hours

25 hours

22 - 28 hours

30 hours

27 - 33 hours

50 hours

46 - 54 hours

100 hours

95-105 hours