73-07-06 PITTS AVIATION ENTERPRISES, INC.: Amdt. 39-1607 as amended by Amendment 39-1620. Applies to Pitts Model S-2A series airplanes, S/N 2001 through 2044.
Compliance required as indicated.
(a) Within the next 5 hours time in service after the effective date of this AD, unless already accomplished, inspect the horizontal stabilizer, P/N 2-3100, front and rear tubes, and the horizontal stabilizer support tubes, front (P/N 2-2123) and rear (P/N 2-2100-109) for cracks.
(1) Disassemble the stabilizers (right and left) in accordance with instructions in Pitts Service Bulletin No. 6, Step 1, or the instructions of paragraph (a)(1) of AD 72-19-05. Also remove horizontal stabilizer root fairing.
(2) Thoroughly clean the exposed portions of all tubes noted above with solvent. Dye-check the tubes in the vicinity of the AN3 bolt holes, and visually inspect for cracks.
(i) If cracks are found, contact AEROTEK, INC., P.O. Box 547, Afton, Wyoming, 83110, for approved repair or repair in accordance with a method approved by the Chief, Engineering and Manufacturing Branch, FAA, Southern Region, Atlanta, Georgia.
(ii) If no cracks are found, reassemble in reverse order of disassembly.
CAUTION: Use care on reassembly to insure that the AN365-1032 nuts on the AN3 bolts, which secure the horizontal stabilizer to the support tubes, are tight enough to prevent any axial movement of the bolt, without having any pre-load or crushing action on the tubes.
(b) Repeat the inspection in paragraph (a) above every 50 hours time in service after initial inspection or until the aircraft has been modified in accordance with Pitts Service Bulletin Number 7, dated March 12, 1973. Modification in accordance with Service Bulletin Number 7 eliminates the need for repetitive inspection.
Amendment 39-1607 became effective April 3, 1973, for all persons except those to whom it was made effective upon receipt of the air mail letter dated March 9, 1973, which contained this amendment.
This amendment 39-1620 becomes effective April 17, 1973.