Airworthiness Directive · Amendment 39-21262 · Flight control system
Bell Helicopter Textron Canada Limited Helicopters
Superseded. A later AD replaced this one: AD 2022-06-20. Comply with the one in force.
This AD applies to Bell Helicopter Textron Canada Limited Model 429 helicopters with a bellcrank assembly part number (P/N) 429-001-523-101, 429-001-523-103, 429-001-532-101, or 429-001-532-103 installed, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada Limited (BHTC) Model 429 helicopters. This AD requires repetitive inspections of certain cyclic and collective assembly bearings. This AD was prompted by reports that precipitation can lead to reduced effectiveness of the grease in the bearings. The actions of this AD are intended to address an unsafe condition on these products.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
Within 12 months after the helicopter was manufactured or 30 days after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 6 months:
(1) Disconnect the forward ends of the collective control tube, longitudinal stability and control augmentation system (SCAS) actuator, and lateral SCAS actuator. Stow the collective control tube and each SCAS actuator to prevent binding.
(2) Slowly move the cyclic stick fore/aft and laterally, and the collective stick up/down from stop to stop to determine if there is any roughness. If there is any roughness in the flight control system, before further flight, replace all six pivot bearings, P/N MS27646-41, in the collective lateral bellcrank assembly and the longitudinal bellcrank assembly.
(3) Inspect the collective arm assembly P/N 429-001-525-101, the lateral arm assembly P/N 429-001-527-101, and the longitudinal arm assembly P/N 429-001-530-101, by rotating each bearing and ensuring each bearing rotates freely. If there is any binding in any arm end bearing or on the longitudinal bellcrank assembly, before further flight, replace each arm end bearing.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
