AD 75-26-01

75-26-01 BRITTEN NORMAN, LTD: Amendment 39-2453. Applies to BN-2A airplanes, all series, certificated in all categories.

Compliance is required as indicated.

To prevent possible failure of the rudder top, center, and bottom hinge brackets with consequent loss of rudder control, accomplish the following:

(a) This paragraph applies to BN-2A airplanes that have not been altered in accordance with both Britten Norman Modifications NB/M/705 and NB/M/777.

(1) Within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 50 hours' time in service, inspect the rudder top, center, and bottom hinge structures for cracks in accordance with Part A and Part B of the section entitled "Inspection" of Britten Norman Service Bulletin No. BN-2/SB.76, Issue 4, dated February 4, 1975, or an FAA-approved equivalent.

(2) Repeat the inspection required by sub-paragraph (a)(1) of this AD at intervals not to exceed 100hours' time in service from the last inspection until the action required by sub-paragraph (a)(4) of this AD is accomplished, at which time the inspection interval may be increased to 500 hours.

(3) If cracks are found in any of the bearing mounting plates as a result of the initial inspection required by sub-paragraph (a)(1) of this AD or any of the 100 hour repetitive inspections required by sub-paragraph (a)(2) of this AD, before further flight, either -

(i) Replace the cracked mounting plates with new or serviceable plates of the same part number, or FAA-approved equivalent parts, and continue to inspect in accordance with the provisions of sub-paragraph (a)(2) of this AD; or

(ii) Alter the rudder hinge areas in accordance with Part A and Part B of the section entitled "Rectification" of Britten Norman Service Bulletin No. BN-2/SB.76, Issue 4, dated February 4, 1975, or an FAA-approved equivalent, following which inspect the hinge structure at intervals not toexceed 500 hours' time in service from the last inspection.

(4) Within 500 hours' time in service after the accomplishment of the inspection required by sub-paragraph (a)(1) of this AD, alter the rudder hinge areas in accordance with Part A and Part B of the Section entitled "Rectification" of Britten Norman Service Bulletin No. BN-2/SB.76, Issue 4, dated February 4, 1975, or an FAA-approved equivalent.

(b) This paragraph applies to BN-2A airplanes that have been altered in accordance with both Britten Norman Modifications NB/M/705 and NB/M/777.

(1) Within 500 hours' time in service after the accomplishment of both modifications NB/M/705 and NB/M/777, or within 25 hours' time in service after the effective date this AD, whichever occurs later, inspect the rudder top, center, and bottom hinge structures for cracks in accordance with Part A and Part B of the section entitled "Inspection" of Britten Norman Service Bulletin No. BN-2/SB.76, Issue 4, dated February 4, 1975,or an FAA-approved equivalent.

(2) Repeat the inspection required by sub-paragraph (b)(1) of this AD at intervals not to exceed 500 hours time in service from the last inspection.

(3) If cracks are found in any of the bearing mounting plates as a result of the inspections required by sub-paragraphs (b)(1) or (b)(2) of this AD, before further flight, replace the cracked mounting plates with new or serviceable plates of the same part number or FAA-approved equivalent parts and continue to inspect the rudder hinge structures at intervals not to exceed 500 hours' time in service from the last inspection.

This amendment becomes effective December 23, 1975.