AD 67-17-01

67-17-01 AERO PRODUCTS: Amdt. 39-417 Part 39 Federal Register May 11, 1967. Applies to Models A6441FN-606 and A6441FN-606A Propellers.

Compliance required as indicated.

(a) On or before July 1, 1967, unless already accomplished, on each propeller in which is installed a fixed spline P/N 6522974, Serial No. 1367 and up, or P/N's 6523110 and 6509978, accomplish the following:

(1) Remove from service all fixed splines P/N's 6523110 and 6509978.

(2) Remove from service any P/N 6522974, Serial No. 1367 and up, fixed spline which does not meet the specification requirements for core hardness. (Reference: Allison Commercial Service Letter 189, Page 7, titled "Fixed Spline," Paragraph B.4.c.)

(b) Within the next 10 hours' time in service, unless already accomplished, each propeller in which is installed a fixed spline P/N 6523110, or 6509978, or P/N 6522974, with Serial No. 1367 and up, must be inspected and marked as required by Allison telegram THO- 641W-LOD, dated April 7, 1967, as modified by Allison telegram THO-662W-LOD, dated April 10, 1967. Thereafter, repetitive daily inspections are required as specified in those telegrams.

(c) If, during the daily inspection, it is determined that a propeller blade is beyond tolerance as set forth in those telegrams, the propeller shall be removed from service and be -

(1) Retained by the operator, with immediate notification to the Chief, Engineering and Manufacturing Branch, FAA Central Region, pending further instructions by him; or

(2) Returned to an approved overhaul base and the Chief, Engineering and Manufacturing Branch, FAA Central Region, notified immediately.

(d) The daily inspection required by this AD may be discontinued when the fixed splines identified in (a)(1) have been removed from service and replaced by airworthy fixed splines, or when the fixed splines identified in (a)(2) have been inspected for core hardness and determined to meet specifications or have been replaced by airworthy fixed splines.

(e) Within the next 10 hours' time in service from the effective date of this amendment, unless already accomplished, each propeller which has not been modified to comply with the restrictor installation of paragraph (a) of AD 67-20-01 and in which is installed a fixed spline Part Number 6508538, accomplish the markings and inspections outlined in paragraphs (b) and (c).

This amendment effective September 20, 1967, for all persons except those to whom it was made effective by telegram dated September 8, 1967.

This supersedes AD 67-12-01.

This directive effective May 11, 1967.

Revised September 20, 1967.