AD 77-07-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | B-N Group Ltd. | BN-2A | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-2 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-20 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-21 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-26 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-27 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-3 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-6 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-8 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN-2A-9 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN2A MK. III | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN2A MK. III-2 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
| aircraft | B-N Group Ltd. | BN2A MK. III-3 | Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series |
Unsafe Condition
Internal corrosion of the aileron mass balance support arm could lead to possible failure of the support arm.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the interior surface of the aileron mass balance support arm in accordance with specified service bulletin steps. Clean, protect, repair, or replace the support arm based on corrosion findings, with replacement required within 300 hours time in service or 3 months if marginal corrosion is found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 25 hours time in service after the effective date of this AD or prior to 3 years since new, whichever occurs later
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
B-N Group Ltd. Models BN-2A Islander and BN-2A Mk III Trislander airplanes, all series, except those incorporating Britten Norman Modification NB/M878.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Aileron Mass Balance Support Arm
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-07-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-07-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes...Show more Subject: Aileron Mass Balance Support Arm Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/18/1977 Make: B-N Group Ltd. Model: BN-2A | BN-2A-2 | BN-2A-20 | BN-2A-21 | BN-2A-26 | BN-2A-27 | BN-2A-3 | BN-2A-6 | BN-2A-8 | BN-2A-9 ...Show more Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-07-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2869 AD NUMBER: 77-07-10 SUBJECT HEADING: Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series ACTION: SUMMARY: DATES: Effective April 18, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-07-10 BRITTEN NORMAN, LTD.: Amendment 39-2869. Applies to Models BN-2A Islander and BN-2A Mk III Trislander airplanes, all series, certificated in all categories, except those airplanes incorporating Britten Norman Modification NB/M878. Compliance is required as indicated, unless already accomplished. To detect internal corrosion and prevent possible failure of the aileron mass balance support arm, accomplish the following: (a) For ailerons modified in accordance with Britten-Norman, Ltd. Modification NB/M/336, within the next 25 hours time in service after the effective date of this AD or prior to 3 years since new, whichever occurs later, accomplish the following: (1) Gain access to and inspect the interior surface of the aileron mass balance support arm in accordance with steps 1 thru 4 of Part 1 and Figure 1 of Britten-Norman, Ltd. Service Bulletin BN-2/SB.98, Issue 1, dated October 27, 1976 (hereinafter S.B. BN- 2/SB.98), or an FAA-approved equivalent. (2) If no corrosion or acceptable corrosion (as defined in Table 1 of Figure 1 of S.B. BN-2/SB.98) is found as a result of the inspection required by paragraph (a)(1) of this AD, clean and protect the interior surface of the support arm and the shank of the bobweight in accordance with subpart (a) of step 5, and reassemble in accordance with steps 6 through 9, of Part 1 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (3) If marginal corrosion (as defined in Table 2 of Figure 1 of S.B. BN- 2/SB.98) is found as a result of the inspection required by paragraph (a)(1) of this AD, before further flight, clean, protect, and reassemble the support arm, in accordance with paragraph (a)(2) of this AD. Thereafter, within the next 300 hours time in service or 3 months, whichever occurs sooner, replace the support arm with a new part of the same part number or an FAA-approved equivalent, and reassemble in accordance with paragraph (a)(2) of this AD. (4) If, during the inspection required by paragraph (a)(1) of this AD, corrosion is found beyond acceptable limits (as defined in Table 3 of Figure 1 of S.B. BN- 2/SB.98), before further flight, replace the support arm with a new part of the same part number, or an FAA-approved equivalent, and reassemble in accordance with paragraph (a)(2) of this AD. (b) For ailerons not modified in accordance with Britten-Norman, Ltd. Modification NB/M/336, within the next 25 hours time in service after the effective date of this AD or prior to 3 years since new, whichever occurs later, accomplish the following: (1) Gain access to and inspect the interior surface of the mass balance support arm in accordance with steps 1 thru 4 of Part 2 and Figure 2 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (2) If no corrosion or acceptable corrosion (as defined in Table 1 of Figure 1 of S.B. BN-2/SB.98) is found as the result of the inspection required by paragraph (b)(1) of this AD, clean and protect the interior surface of the support arm and the shank of the bobweight in accordance with subpart (a) of Step 5, Part 1, and repair the support arm in accordance with Figure 2 and reassemble in accordance with steps 6 thru 9, of Part 2 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (3) If marginal corrosion (as defined in Table 2 of Figure 1 of S.B. BN- 2/SB.98) is found as a result of the inspection required by paragraph (b)(1) of this AD, before further flight, clean, protect, repair, and reassemble the support arm and shank of the bobweight in accordance with paragraph (b)(2) of this AD. Thereafter within the next 300 hours time in service or 3 months, whichever occurs sooner, replace the support arm in accordance with the repair and reassembly instructions specified in Part 3 and Figure 3, of S.B. BN-2/SB.98, or an FAA-approved equivalent. (4) If, during the inspection required by paragraph (b)(1) of this AD, corrosion is found beyond acceptable limits (as defined in Table 3 of Figure 1 of S.B. BN- 2/SB.98), before further flight, replace the support arm in accordance with Part 3 and Figure 3 of S.B. BN-2/SB.98, or an FAA-approved equivalent. This amendment becomes effective April 18, 1977. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_77-07-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-07-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes...Show more Subject: Aileron Mass Balance Support Arm Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/18/1977 Make: B-N Group Ltd. Model: BN-2A | BN-2A-2 | BN-2A-20 | BN-2A-21 | BN-2A-26 | BN-2A-27 | BN-2A-3 | BN-2A-6 | BN-2A-8 | BN-2A-9 ...Show more Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-07-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2869 AD NUMBER: 77-07-10 SUBJECT HEADING: Airworthiness Directives; Britten Norman Models BN-2A Islander and BN-2A Mk III Trislander Airplanes, All Series ACTION: SUMMARY: DATES: Effective April 18, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-07-10 BRITTEN NORMAN, LTD.: Amendment 39-2869. Applies to Models BN-2A Islander and BN-2A Mk III Trislander airplanes, all series, certificated in all categories, except those airplanes incorporating Britten Norman Modification NB/M878. Compliance is required as indicated, unless already accomplished. To detect internal corrosion and prevent possible failure of the aileron mass balance support arm, accomplish the following: (a) For ailerons modified in accordance with Britten-Norman, Ltd. Modification NB/M/336, within the next 25 hours time in service after the effective date of this AD or prior to 3 years since new, whichever occurs later, accomplish the following: (1) Gain access to and inspect the interior surface of the aileron mass balance support arm in accordance with steps 1 thru 4 of Part 1 and Figure 1 of Britten-Norman, Ltd. Service Bulletin BN-2/SB.98, Issue 1, dated October 27, 1976 (hereinafter S.B. BN- 2/SB.98), or an FAA-approved equivalent. (2) If no corrosion or acceptable corrosion (as defined in Table 1 of Figure 1 of S.B. BN-2/SB.98) is found as a result of the inspection required by paragraph (a)(1) of this AD, clean and protect the interior surface of the support arm and the shank of the bobweight in accordance with subpart (a) of step 5, and reassemble in accordance with steps 6 through 9, of Part 1 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (3) If marginal corrosion (as defined in Table 2 of Figure 1 of S.B. BN- 2/SB.98) is found as a result of the inspection required by paragraph (a)(1) of this AD, before further flight, clean, protect, and reassemble the support arm, in accordance with paragraph (a)(2) of this AD. Thereafter, within the next 300 hours time in service or 3 months, whichever occurs sooner, replace the support arm with a new part of the same part number or an FAA-approved equivalent, and reassemble in accordance with paragraph (a)(2) of this AD. (4) If, during the inspection required by paragraph (a)(1) of this AD, corrosion is found beyond acceptable limits (as defined in Table 3 of Figure 1 of S.B. BN- 2/SB.98), before further flight, replace the support arm with a new part of the same part number, or an FAA-approved equivalent, and reassemble in accordance with paragraph (a)(2) of this AD. (b) For ailerons not modified in accordance with Britten-Norman, Ltd. Modification NB/M/336, within the next 25 hours time in service after the effective date of this AD or prior to 3 years since new, whichever occurs later, accomplish the following: (1) Gain access to and inspect the interior surface of the mass balance support arm in accordance with steps 1 thru 4 of Part 2 and Figure 2 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (2) If no corrosion or acceptable corrosion (as defined in Table 1 of Figure 1 of S.B. BN-2/SB.98) is found as the result of the inspection required by paragraph (b)(1) of this AD, clean and protect the interior surface of the support arm and the shank of the bobweight in accordance with subpart (a) of Step 5, Part 1, and repair the support arm in accordance with Figure 2 and reassemble in accordance with steps 6 thru 9, of Part 2 of S.B. BN-2/SB.98, or an FAA-approved equivalent. (3) If marginal corrosion (as defined in Table 2 of Figure 1 of S.B. BN- 2/SB.98) is found as a result of the inspection required by paragraph (b)(1) of this AD, before further flight, clean, protect, repair, and reassemble the support arm and shank of the bobweight in accordance with paragraph (b)(2) of this AD. Thereafter within the next 300 hours time in service or 3 months, whichever occurs sooner, replace the support arm in accordance with the repair and reassembly instructions specified in Part 3 and Figure 3, of S.B. BN-2/SB.98, or an FAA-approved equivalent. (4) If, during the inspection required by paragraph (b)(1) of this AD, corrosion is found beyond acceptable limits (as defined in Table 3 of Figure 1 of S.B. BN- 2/SB.98), before further flight, replace the support arm in accordance with Part 3 and Figure 3 of S.B. BN-2/SB.98, or an FAA-approved equivalent. This amendment becomes effective April 18, 1977. FOOTER:
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