Check thrust bearing nuts for tightness on new or newly overhauled engines at the first 50 hour inspection following installation. Subsequent inspections on thrust bearing nuts will be made at each third 50 hour inspection. From the above statement, at what intervals should you check the thrust bearing nuts for tightness?

Check thrust bearing nuts for tightness on new or newly overhauled engines at the first 50 hour inspection following installation. Subsequent inspections on thrust bearing nuts will be made at each third 50 hour inspection. From the above statement, at what intervals should you check the thrust bearing nuts for tightness?

• A. 50 hours
• B. 100 hours
• C. 150 hours
• D. 200 hours

Answer: (C)

The schedule uses 50-hour blocks, with checks on every third block. Start with the first check at 50 hours. Then skip the next two 50-hour checks and perform the next one on the third 50-hour block. That puts the next check at 150 hours, and continuing the pattern yields checks at 300, 450, and so on. So the repeating interval between checks is 150 hours.

The schedule uses 50-hour blocks, with checks on every third block. Start with the first check at 50 hours. Then skip the next two 50-hour checks and perform the next one on the third 50-hour block. That puts the next check at 150 hours, and continuing the pattern yields checks at 300, 450, and so on. So the repeating interval between checks is 150 hours.