AS350AStar · H125

A gap has been found between bolted assemblies under the main gearbox suspension bar attachment fittings on certain Airbus helicopters. This AD requires replacing affected front and rear attachment fittings, screws, nuts, and washers, and prohibits installation of any affected parts unless they are new.

A cargo load was lost during a cargo swing operation due to incorrect adjustment of the release cable on the cargo swing emergency release control. This AD requires a one-time inspection of the cargo swing emergency release control and corrective actions if needed.

Cracks have been found in the vertical fin spar and upper attachments of certain Airbus helicopters. This AD requires inspections for cracking and replacement of the upper fin assembly with a modified version to eliminate the need for repetitive inspections.

The engine may remain at idle when the throttle twist grip is turned to FLIGHT mode. This AD requires modification of the throttle twist grip and inspection, with the modification serving as terminating action for repetitive inspections.

Broken cargo swing frames have been reported on certain Airbus helicopters. This AD requires repetitive inspections of the cargo swing installation and frame with corrective action as needed.

A sliding door locked in the open position detached from a helicopter during flight, creating a safety hazard. The AD requires modifying upper rail rollers, installing labels on sliding doors, and prohibits installation of affected upper rail rollers or doors with affected rollers.

Main rotor blades on certain Airbus helicopters may experience debonding on the leading edge protection. The AD requires repetitive tap inspections of the main rotor blades and corrective actions based on inspection results, and prohibits installation of affected blades unless requirements are met.

Certain flight control Flexball cables were found to have a non-conformity during production that could affect flight control integrity. This AD requires removing affected Flexball cables from service and prohibits their installation on any affected helicopter.

Goodrich externally-mounted hoists have been failing lower load limit inspections. This AD requires replacing unmodified hoists, installing placards, revising the RFM, deactivating or removing hoists after partial peel out, repetitively inspecting cables and clutches, and establishing operating limitations.

Certain FADEC units installed on AS350B3 and EC130T2 helicopters have been identified as unsafe. This AD requires revising the rotorcraft flight manual with a new temporary procedure and prohibits installation of affected FADECs; helicopters with modified serviceable FADECs must remove the temporary procedure.

This AD, which required inspecting sliding doors and replacing or removing certain components, is being removed. The FAA has determined that the in-flight loss of a sliding door that prompted this AD was an isolated case caused by incorrect operation and maintenance error, not a fleet-wide safety issue.

Increased vibration has been reported during flight on certain Airbus Helicopters models due to main rotor pitch rod upper link issues. The AD requires application of alignment markings and repetitive inspections of the main rotor pitch rod upper links, with corrective actions as needed.

Certain helicopters have an electrical wiring non-conformity in the hydraulic system that can cause the tail rotor load compensator solenoid to de-energize when the HYD cut-off switch is activated. This AD requires installing a cockpit placard, performing functional checks of solenoids, and completing a modification if necessary.

An Emergency Flotation System (EFS) float compartment failed to inflate during maintenance inspection. This AD requires inspecting certain EFS units and either marking or removing affected parts from service.

This AD is being removed because the reported failure of main rotor hub-to-mast attachment screws was determined to be an isolated case caused by a maintenance mistake, and no unsafe condition is likely to exist on other helicopters in the fleet. No action is required.

Certain Airbus helicopter cyclic stick grips have electrical wiring issues with the hoist control system. This AD requires incorporating a modification procedure and removing previously installed placards and rotorcraft flight manual amendments.

Lanyards on certain litter kits can loop around directional control pedal stubs, restricting pedal movement. This AD requires modification of the lanyard attachment location on affected litter kits.

A tail rotor gearbox actuating rod may rupture, reducing yaw control during landing. This AD requires dye penetrant inspection of the TGB actuating rod for cracks and replacement if found.

Multiple errors exist in service information for hoist operator control units on certain Airbus Helicopters. This AD requires using corrected service information, completing required modifications, and prohibits installation of affected hoists until actions are accomplished.

Inconsistencies were found between inspection and maintenance requirements for tail rotor drive shaft bearings in the airworthiness directive versus the maintenance manual. This AD requires replacing certain tail rotor bearings with a specified part-numbered bearing and performing repetitive inspections on another part-numbered bearing.

Tail rotor pitch rod elastomeric ball joints have been found damaged on certain Airbus helicopters. This AD requires repetitive inspections of the tail rotor pitch rod for damage and allows extended inspection intervals under certain conditions per EASA requirements.

A main rotor mast upper bearing retaining ring may be missing or incorrectly installed, potentially causing bearing failure. This AD requires a one-time inspection to verify correct installation of the retaining rings and repetitive inspections of the sealant bead for damage, with corrective actions as needed.

Engine may remain at idle when the throttle twist grip is moved from forced idle to flight position. This AD requires modifying the electrical system of the throttle twist grip and inspecting and correcting microswitch electrical harness routing.

Certain tail rotor blade leading edge protection shields have debonded on these helicopter models. The AD requires repetitive inspections of affected tail rotor blades and replacement if damage is found.

Main rotor gearbox suspension bar attachment bracket bolts may have missing bolt heads, which could affect helicopter safety. The AD requires a one-time visual inspection of all 16 attachment bracket bolt heads, and depending on findings, measuring torque values, replacing bolts/washers/nuts, and sending documentation to Airbus Helicopters.

Some NR indicators on certain AS350B2 helicopters display incorrect information, creating a safety hazard. The AD requires testing the main rotor RPM indicator and altering wiring if necessary.

Main rotor servo actuators on certain Airbus Helicopters may experience internal slippage, which caused a sudden nose-up attitude and control vibrations in at least one incident. This AD requires inspection of the M/R servo actuators, replacement if needed, application of slippage marks, and reporting of findings.

This AD is being removed because the unsafe condition affecting tail rotor pitch horn assemblies in these Airbus helicopter models has been eliminated. No further inspections or replacements are required.

Buckle knobs on certain Anjou Aeronautique Model 358 torso restraint systems have been reported breaking, creating a safety hazard. This AD requires removal from service of affected restraint systems within the specified compliance schedule.

Emergency float kit pull cables may be installed incorrectly, making the float activation handle difficult to pull in an emergency. This AD requires repetitive inspections of the emergency float kit installation on the pilot cyclic.

Certain Pall Aerospace Inlet Barrier Filter elements are unsafe for operation in wet weather and may cause engine damage. The AD prohibits operating these helicopters with the affected filters in wet weather, requires replacement or drying of wet filters, and prohibits reinstallation or installation of the affected filter elements on any helicopter.

An earlier AD for Model AS350B3 helicopters referenced an incorrect monostable toggle switch part number. This revision corrects that part number error while maintaining all other requirements of the original directive.

Main rotor mast jet oil lubrication hoses may become blocked, potentially causing unsafe operating conditions. This AD requires inspection of the oil hose on affected helicopters.

Hydraulic pump drive pulley bearings can fail and cause belt failure. This AD requires periodic greasing and inspection of the bearing for bronze particles and deterioration.

Cracks have been found in bi-directional suspension cross-bars on certain Airbus helicopter models. This AD requires inspecting each cross-bar to prevent unsafe conditions.

Cracks can develop in the reinforcement angles where the rear structure connects to the tailboom, potentially leading to loss of the tail boom and helicopter control. This AD requires repetitive inspections of these reinforcement angles at 10-hour intervals and inspection of screw holes as a terminating action.

The swashplate assembly rotating star may crack during reconditioning, potentially causing loss of helicopter control. The AD requires inspection of the rotating star for cracks and removal of any cracked components.

Failed bearings can cause vibration, tail rotor failure, and loss of helicopter control. This AD requires installing placards, revising the flight manual, inspecting and replacing laminated half-bearings as needed, and performing modifications to correct airspeed limitations.

Tail rotor pitch control rods on certain Airbus Helicopters may fail, causing loss of tail rotor control and subsequent loss of helicopter control. The AD requires checking control rods for play within 30 hours time-in-service and thereafter at 30-hour intervals.

Tail gearbox control levers on certain Airbus Helicopters have been reported to develop cracks, which could lead to loss of tail rotor control and loss of helicopter control. This AD requires repetitive visual inspections of the tail gearbox control lever for cracks and inspection of additional areas at specified intervals, with replacement of any cracked lever.

Tail rotor blade trailing edge tabs on certain Airbus helicopters may debond, causing excessive vibration and loss of control. This AD requires installing additional rivets to secure each tail rotor blade trailing edge tab and inspecting for debonding after installation.

Insufficient clearance between the main rotor collective pitch lever locking stud and locking strip can cause the collective to become inadvertently locked in the low pitch position, risking loss of control. This AD requires measuring the distance between the locking stud and locking strip and repairing the stud if clearance is insufficient.

A crack was discovered in the center cross-member at the yaw control attachment point on some helicopters, which could reduce yaw control and cause loss of helicopter control. This AD requires inspection of the cross-member and doublers, and installation of these components if missing.

Certain part-numbered nuts and washers on the lower ball-joint bolt of sliding doors can detach in flight, potentially causing loss of the door. Remove these parts from service on affected helicopters.

Improper casting of tail rotor gearbox casing assemblies may cause cracks in control lever attachment yokes, leading to loss of tail rotor pitch control. This AD requires inspecting for cracks and replacing the tail rotor gearbox if needed.

Tail rotor control stop screws may be loose or misaligned, potentially limiting yaw authority and compromising helicopter control. Inspect the screws for correct alignment and adjust any that are misaligned.

Certain hydraulic main and tail rotor servo-controls have excessive axial play on bearings that could jam the distributor slide valve and lock the hydraulic flight controls. This AD requires determining whether an affected servo-control is installed and replacing it before further flight.

Cracks have been found on Aerazur emergency flotation gear attachment brackets installed on certain Eurocopter helicopters, which could cause failure of the emergency flotation system during water landing. This AD requires an initial and recurring inspection of the brackets for cracks, and replacement of any cracked bracket with an airworthy one.

Cracks have been found in the rear roller support shaft and rear fitting of sliding doors, which could allow the door to contact the rotor system and damage the helicopter. This AD requires visual and dye penetrant inspections of these components and replacement if cracks are found.

The manufacturer-installed Aircraft Parts Corporation starter generator exceeds the shaft horsepower extraction allowed for Turbomeca engines, which can reduce engine surge margin and cause engine failure. The AD requires revising the Rotorcraft Flight Manual to limit starter generator current to 180 amperes and installing a placard on the instrument panel indicating this limitation.

Emergency flotation gear container assemblies may fail due to age because their 10-year replacement limit is no longer recorded in maintenance programs. This AD requires replacing affected container assemblies at specified time limits based on manufacture date.

Forward servo-control hydraulic hoses on certain AS350 helicopters can become damaged and leak fluid that may ignite in flight, risking loss of rotor control and fire. The AD requires installing protection sleeves over these hoses to prevent damage and fluid leakage.

Cracks have been discovered in the upper fin spar on AS355N helicopters, with similar risk on AS350 models due to design similarity. This AD requires modification of the upper and lower fin attachments to prevent fin failure and loss of control.

Engine flameouts have occurred due to a failed 41-tooth pinion in the engine accessory gearbox caused by improper starter-generator torque damping adjustment. This AD requires adjustment of the starter-generator damping assembly using a new procedure to prevent pinion failure, fuel pump stoppage, and engine flameout.

Certain L'Hotellier Halon 1211 fire extinguishers have been filled with contaminated gas that reduces fire suppression capability and may release toxic fumes. Operators must replace each affected fire extinguisher with an airworthy unit or one reconditioned with pure Halon 1211 per L'Hotellier procedure ITR70030-00.

Some main and tail rotor servo-controls do not conform to approved design and may cause distributor slide valve jamming, reducing controllability and risking loss of control. This AD requires replacing all affected servo-controls identified by part number and serial number.

A short circuit in the hoist motor brush power supply wiring can cause an uncommanded squib firing that cuts the hoist cable, creating an unsafe condition. This AD requires inspection and correction of the hoist motor wiring to prevent untimely squib firing.

A manufacturing defect in servo-control caps can prevent the distributor from being mechanically stopped, potentially causing loss of helicopter control. The AD requires identification and replacement of affected servo-control caps.

Turbomeca Arriel 2B and 2B1 turboshaft engines installed on certain Eurocopter helicopters have an unsafe condition. This AD requires specific corrective actions to address the identified safety issue.

Ice can form in the hydraulic system due to condensation during cold weather operation, potentially causing unintended flight control movement and loss of control. The AD requires replacing hydraulic fluid at specified intervals when operating in cold weather.

In-flight failures of hydraulic drive belts and drive shafts can cause loss of hydraulic power to the flight control system. This AD requires replacing the affected drive belt and reducing the lubrication interval for the drive shaft splines from 550 hours to 110 hours.

Cracks have been discovered in the tapered housings of main servo-control units on certain Eurocopter helicopters, which could lead to loss of main rotor control. This AD requires inspecting the tapered housing for cracks within 10 hours of service time and either retorquing the attachment nut if no crack is found or replacing the unit if a crack is detected.

Pilots experienced restricted cyclic stick travel when using factory-installed cyclic sticks in helicopters modified with a Geneva P132 console under a specific STC. The AD requires installing new Geneva right and left side cyclic control sticks and modifying the cyclic grips and co-pilot cyclic stand receptacle to prevent loss of control during high lateral CG operations.

Some fuel bleed levers have separated in flight due to insufficient control cable tension, risking damage to the tail rotor blade and loss of helicopter control. This AD requires removing and modifying the fuel bleed lever.

Fuel transfer lines and air exhaust ducts can chafe due to vibration, potentially causing fuel leaks and fire hazards. Operators must inspect these components for chafing and holes, and reposition the duct if necessary to maintain minimum clearances.

The main rotor swashplate bearing can fail, causing loss of helicopter control. The AD requires repetitive inspection and lubrication of the main rotor swashplate and bearing at intervals not exceeding 100 hours time-in-service.

Certain Eurocopter helicopters have main or tail servocontrols with manufacturing defects that could fail and cause loss of control. Remove affected servocontrols before further flight or within 550 hours time-in-service or 24 months, whichever occurs first.

Internal corrosion of the Siren cargo hook locking catch can weaken it and cause unexpected cargo load release. This AD requires modifying the Siren cargo hook and inspecting the locking catch for corrosion.

The 2nd stage turbine disk may rub on the 2nd stage turbine nozzle guide vanes, causing engine rubbing noise and potentially leading to complete engine failure. The AD requires repetitive checks for engine rubbing noise and free rotation of the gas generator, or installation of modification TU 202 to terminate these checks.

Neoprene seals on main gearbox opening cowlings lack required fire protection and could allow engine compartment fires to reach the gearbox, risking loss of control. Replace neoprene seals with glass/silicone seals.

Certain main and tail rotor parts may have incorrect time-in-service or cycle records on their Equipment Log Cards. Operators must verify and correct these records, and replace any parts that have exceeded their life limits within 50 hours of flight time.

Second stage gas generator turbine blades in certain Turbomeca Arriel engines have failed in flight, causing engine shutdown. Owners must replace M03 modules that were modified to TU 204 standard with unmodified M03 modules.

The engine oil tank breather pipe where it passes through the firewall may not be fireproof, allowing fire to spread between compartments. Install fireproofing on the breather pipe.

The ASU No. 2 printed circuit board may be missing a critical resistor R8, which could prevent proper voltage regulation to warning lights and the rotor RPM display. Inspect the PCB and replace it with an airworthy unit containing the resistor if it is missing.

Several cases of centrifugal compressor impeller blade ruptures have occurred in service, which can cause acoustic excitation leading to contained blade ruptures and power loss. This AD requires insertion and bonding of a sleeve in the compressor bleed valve attachment boss to prevent these failures.

Sliding door rollers can wear excessively and separate from the middle rail during flight, potentially causing the door to separate and damage critical flight components. Operators must measure roller and rail dimensions to detect wear and install a placard prohibiting in-flight door operation if excessive wear is found.

Certain ferry fuel tank installations may have inadequate electrical bonding between the electrostatic ground connector and its support, creating a fire and explosion hazard during refueling. Before refueling any installed tank, operators must measure the electrical resistance between the connector and tank filler neck; if resistance exceeds 1.5 milliohms, the tank must not be refueled.

Certain SIREN load release units (cargo hooks) may have a defect that prevents load release, creating a hazard in emergency situations. The AD requires determining the cargo hook serial number, measuring clearance between the locking catch and cargo hook, and removing unairworthy cargo hooks from service.

The cantilevered axis of the free turbine can move from its design position and cause blade trajectories to exceed the current containment area, potentially leading to uncontainment during an overspeed event and helicopter damage. This AD requires installation of containment shield rings around the free turbine blade area and a double support around the gearbox free turbine bearing housing.

Fatigue cracks have been found in tail rotor hub pitch change plate SNR bearings, which could lead to bearing seizure and loss of tail rotor effectiveness. The AD requires replacement of the affected bearing.

Bonding failure between the metal bushing and STARFLEX star arm ends can cause severe lateral vibrations and loss of control. The AD requires visual checks for gaps between the adhesive bead and metal bushing before each engine start and at 4-hour intervals, with replacement of defective STARFLEX units before further flight.

A collective locking device can inadvertently engage during flight, causing the collective pitch control to lock in the full-down position and resulting in loss of control. This AD requires replacement of the collective locking device with a newly-designed locking device.

Cracks have been discovered in tail rotor blade skins that could lead to blade failure, severe vibration, and loss of helicopter control. The AD requires visual inspection of tail rotor blades for cracks before further flight and at specified intervals, with replacement of any cracked blades.

Rigid tube fuel manifolds in certain Honeywell LTP 101 and LTS101 engines can crack and leak fuel due to low-cycle fatigue, potentially causing an in-flight fire. This AD requires removal of affected fuel manifolds and replacement with serviceable assemblies, and establishes a new life limitation for these engines.

The tail rotor pitch change spider assembly bearing spacers can rotate, which may lead to bearing seizure and loss of tail rotor control. Operators must mark the spider assembly to detect rotation, check daily that marks are aligned, and modify the assembly if rotation is detected or at the next 500-hour inspection.

Fuel pumps in these engines can develop excessive internal drive spline wear, which may cause fuel pump failure and total engine power loss. This AD reduces inspection intervals for the fuel pump internal drive splines and requires replacement of pumps with wear beyond specified limits.

Cracks in the main gearbox suspension cross beam can cause gearbox rotation, severe vibrations, and forced landings. This AD requires inspecting the cross beam for cracks and replacing it if found.

Cracks in the fuselage frame at the fuselage-to-tailboom interface can lead to tailboom failure and loss of control. Inspect the frame for cracks and verify fastener torque at extended intervals.

Ground resonance due to reduced structural stiffness in main rotor head and main gearbox suspension components could lead to loss of control. Operators must perform inspections of main rotor head components, main gearbox suspension bars, and ground resonance prevention system components.

Turbomeca Arriel 1 series turboshaft engines may experience gas generator rear bearing failure, which could lead to uncommanded engine shutdown. Install a chip detector with electronic warning on the rear bearing oil return system.

Cracking has occurred in heat shield attachment areas on the tail rotor drive shaft forward fairing, which could cause the heat shield to detach in flight and damage the rotor blades. This AD requires visual inspection of the fairing for cracks and periodic detailed inspections, with replacement of any fairing found to have cracks.

Crouzet single-pole circuit breakers in these helicopters can lose electrical continuity between terminals, potentially disabling emergency flotation gear or other optional systems. This AD requires replacing the affected circuit breakers.

Certain tailboom attachment bolts on these helicopters do not meet design strength specifications and could fail, potentially causing tailboom separation and loss of control. The AD requires replacing the affected attachment bolts located above the cargo compartment floor.

Gas generator turbine disk tenons may fail, causing total loss of engine power and inflight shutdown. The AD requires removal from service of suspect disks for one-time inspection of the disk tenon area.

Power turbine disk failures have occurred following No. 3 bearing failures in LTS101 series turboshaft engines, risking uncontained engine failure. This AD requires incorporation of design modifications to the power turbine rotor.

Some cyclic pitch change control rod end fittings were not safetied at the factory, which could cause loss of tightening torque and loss of helicopter controllability. Inspect the rod end fittings for proper safetying and replace the rod if they were not safetied.

LTS101 and LTP101 engine fuel pumps can fail due to wear of internal drive splines, causing total engine power loss. Operators must perform initial and repetitive inspections for spline wear and replace fuel pumps exceeding wear limits; removed pumps must be returned to the manufacturer.