AD 87-09-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105A | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105C | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105LS A-1 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105LS A-3 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105S | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | MBB-BK 117 A-1 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | MBB-BK 117 A-3 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | MBB-BK 117 A-4 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | MBB-BK 117 B-1 | Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 Series Helicopters |
Unsafe Condition
Failure of the secondary main rotor blade retention bolt and possible loss of control of the main rotor blade.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect bolts with more than 100 hours' time in service for cracks using magnetic particle or dye penetrant inspection. For bolts with less than 100 hours, inspect before accumulating 100 hours. Replace cracked bolts before further flight. Conduct inspections every 100 hours' time in service. Reinstall bolts with specific lubrication and torque instructions.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Prior to further flight (for cracked bolts) and at intervals not exceeding 100 hours' time in service since last inspection.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
MESSERSCHMITT-BOLKOW-BLOHM GMBH Model BO-105, BO-105LS, and BK-117 series helicopters with main rotor blade secondary bolt P/N's 105-14101.35, 105-14101.79, 105-14101.11, and 105-141021.05 installed.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.