Head, Rotary Wing
Parts to be inspected.
a. Strap Pack Bolt Inspection.
Perform the following inspection at ambient temperatures of 50 degrees F to 120
degrees F (10 degrees C to 49 degrees C). Do not wear sunglasses or glasses with
polarized or photometric grey lenses while performing this inspection. This
inspection is to be done without developer, do not apply developer. Critical
detectable flaw size is 0.020 inch long x 0.010 inch deep.
(1) Within the next 50 flight hours, remove Lead Lag Link IAW paragraph 5.33, TM 1-1520-238-23.
(2) Clean inner diameter of Strap Pack Outboard Bolt using Isopropyl Alcohol. Do not use any abrasive.
(3) Visually inspect for cracks, none allowed.
(4) Using a cotton swab soaked in Type I, Method C, Sensitivity Level 4, Fluorescent Penetrant Dye (MIL-1-
25135) wet entire inner diameter of Strap Pack Bolt. Use black light to ensure complete coverage. At temperatures
below 60 degrees F (15 Degrees C), allow penetrant to remain on part for at least one hour. At temperatures above 60
degrees F (15 degrees C), allow the penetrant to remain on the part for at least 30 minutes. Make sure the surface
remains wet throughout the entire dwell time. Reapply penetrant if necessary.
(5) Use a clean dry cloth to remove as much excess surface penetrant as possible. Using a clean Lint Free
Cloth dampened with solvent (MIL-1-25135), remove residual background surface penetrant. Use black light to ensure all
excess penetrant is removed. Allow 30 minutes dwell time before continuing the inspection.