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FAA orders · airworthiness directive · historical

97-26-02: Main Rotor Mast Flange Crack Inspection

FAA order 97-26-02 is an airworthiness directive in force since December 31, 1997. The FAA's subject line: Main Rotor Mast Flange Crack Inspection. It names Messerschmitt-Boelkow-Blohm BO-105, Messerschmitt-Bolkow-Blohm BO 105: about 31 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: rotorcraft systems.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Airbus Helicopters Deutschland GmbH
Models
BO-105A, BO-105C, BO-105LS A-1, BO-105LS A-3, BO-105S
On this site
Messerschmitt-Boelkow-Blohm BO-105 11 registered
Messerschmitt-Bolkow-Blohm BO 105 20 registered

Dates and paperwork

In force since
December 31, 1997
Published
December 16, 1997
Docket
97-SW-44-AD
Replaced by
2021-07-08
Status
Historical
The FAA's document
Read the order on the FAA's site

The FAA's summary their words, unchanged

This amendment adopts a new airworthiness directive (AD) that is applicable to Eurocopter Deutschland GmbH (ECD) (Eurocopter Deutschland) Model BO-105A, BO-105C, BO- 105S, BO-105LS A-1, and BO-105LS A-3 helicopters; and Eurocopter Canada Ltd. Model BO-105LS A-3 helicopters. This action requires visual inspections for cracks in the ribbed area of the main rotor mast flange (flange). This amendment is prompted by a report of an operator discovering a crack in the flange after experiencing in-flight vibrations. The actions specified in this AD are intended to detect cracks in the flange, which, if not detected, could result in failure of the flange and subsequent loss of control of the helicopter.

The order itself the regulatory text, as published

Show the full text (3,793 characters)
97-26-02 EUROCOPTER DEUTSCHLAND GmbH (ECD) and EUROCOPTER CANADA LTD.: Amendment 39-10245. Docket No. 97-SW-44-AD. \n\n\tApplicability: Eurocopter Deutschland GmbH Model BO-105A, BO-105C, BO-105S, BO-105LS A-1, and BO-105LS A-3 helicopters and Eurocopter Canada Ltd. BO-105LS A-3 helicopters, certificated in any category. \n\n\tNOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (c) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo detect cracks in the main rotor mast flange (flange), which, if not detected, could result in failure of the flange and subsequent loss of control of the helicopter, accomplish the following: \n\n\t(a)\tBefore further flight and thereafter at intervals not to exceed 100 hours time-in-service, visually inspect the flange in the ribbed area for cracks using a 5-power or higher magnifying glass in accordance with paragraphs 2.A.1. and 2.A.2. of the Accomplishment Instructions of Eurocopter Deutschland GmbH Alert Service Bulletin No. ASB-BO 105-10-110, dated August 27, 1997, or Eurocopter Canada Alert Service Bulletin No. ASB-BO 105 LS-10-9, dated September 11, 1997, as applicable.(b)\tIf a crack is found, remove the cracked main rotor mast and replace it with an airworthy main rotor mast. \n\n\t(c)\tAn alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Rotorcraft Standards Staff, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Standards Staff. \n\n\tNOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. \n\n\t(d)\tSpecial flight permits will not be issued. \n\n\t(e)\tThe inspection shall be done in accordance with Eurocopter Deutschland GmbH Alert Service Bulletin No. ASB-BO 105-10-110, dated August 27, 1997, or Eurocopter Canada Alert Service Bulletin No. ASB-BO 105 LS-10-9, dated September 11, 1997, as applicable.These incorporations by reference were approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. Copies may be inspected at the FAA, Office of Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\tNOTE 3: The subject of this AD is addressed in Luftfahrt-Bundesamt (Germany) AD 97-275, dated September 25, 1997, and in Transport Canada AD CF-97-18, dated September 30, 1997. \n\n\t(f)\tThis amendment becomes effective on December 31, 1997.

Related safety bulletins advice on the same designs, not orders

2012-10-03SW-12-45 · Garmin Model 400W/500W Series GPS-WAAS Navigation System
2008-08-27SW-08-42 · Emergency Float with Liferaft Kits (kits)

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/97-26-02.json · aircraft systems.