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)
Related safety bulletins advice on the same designs, not orders
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.
