Sikorsky airworthiness directives
87 ADs in the reference matching Sikorsky — from the Federal Register, checked every weekday. Applicability may depend on serial and effectivity: verify against the official AD before any maintenance action.
Reference last synced: 10/24/2026 04:00 UTC · 10,463 ADs indexed
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is superseding Airworthiness Directive (AD) 2022-02-01 for Sikorsky Aircraft Corporation Model S-92A helicopters with certain part-numbered main rotor stationary swashplate assemblies (swashplate assemblies) that had accumulated 1,600 or more total hours time-in- service (TIS) installed. AD 2022-02-01 required visually inspecting the swashplate assembly at specified intervals and depending on the results, re…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is superseding Airworthiness Directive (AD) 2020-26- 13, which applied to certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. AD 2020-26-13 required establishing the life limit for certain part-numbered horizontal stabilizer root fittings FWD (forward root fittings) and certain part-numbered stabilizer strut fittings. AD 2020-26-13 also required repetitively inspecting certain parts, an…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation Model S-76D helicopters. This AD was prompted by reports that certain Thales global positioning system (GPS) satellite based augmentation system (SBAS) receivers provided, under certain conditions, erroneous outputs on aircraft positions. This AD requires replacing affected GPS receivers and prohibits installing those GP…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation Model S-92A helicopters. This AD was prompted by a cracked main rotor stationary swashplate assembly (swashplate assembly). This AD requires visually inspecting the swashplate assembly at specified intervals and depending on the results, removing the swashplate assembly from service. The FAA is issuing this AD to address…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by an incident of a side facing utility seat detaching from wall attachment points. This AD requires modifying certain side facing utility seats and observer seats, and prohibits installing those seats unless the modification has been accomplished. The FAA is issui…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is superseding Airworthiness Directive (AD) 2021-04-16 which applied to certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. AD 2021-04-16 required a one-time inspection of the landing gear for components with non-conforming threads and removal of any non-conforming threaded hinge pin and main landing gear (MLG) and nose landing gear (NLG) actuator pins. AD 2021-04-16 also prohibited ins…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the manufacturer discovering nonconforming threads, resulting in a life limit reduction on multiple landing gear components including threaded hinge pins and main landing gear (MLG) and nose landing gear (NLG) actuator pins. This AD requires a one-time inspectio…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by seven incidents of fatigue cracks in the horizontal stabilizer root fitting FWD (forward root fitting). This AD requires establishing the life limit of certain part-numbered forward root fittings, establishing the life limit of certain part-numbered stabilizer strut fit…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by two incidents of erroneous low oil pressure caution cockpit indications and unintended actuation of the main gearbox (MGB) auto bypass valve. This AD requires installing auxiliary circuit breaker modification (MOD) kits and inserting a Rotorcraft Flight Manual (…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation Model S-76C helicopters. This AD was prompted by reports of inaccurate main gear box (MGB) indications in flight. This AD requires updating the remote data acquisition unit (RDAU) software and re-identifying the RDAU and, for certain helicopters, updating the software of the display unit (DU) and re- identifying the DU.…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-70, S-70A, S- 70C, S-70C(M), and S-70C(M1) helicopters. This AD was prompted by four incidents of disbonding between the tail rotor (T/R) blade pitch horn and the torque tube. This AD requires recurring visual and tap inspections of the T/R blade, and depending on the outcome, replacing the T/R blade.…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is superseding Airworthiness Directive (AD) 2018-10-07 for Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. AD 2018-10-07 required inspecting the engine collective position transducer (CPT). This new AD retains the requirements of AD 2018-10-07 and expands the applicability. This AD is prompted by the determination that an additional part-numbered engine CPT is affected by the same unsafe co…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by fatigue analysis indicating stress concentrations, as well as the discovery of a helicopter with a crack in the station (STA) 362 frame and skin. This AD requires inspecting the main transmission forward and aft frame assemblies and adjacent skins for a crack an…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are superseding Airworthiness Directive (AD) 2017-14-03 for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. AD 2017-14-03 required an inspection and reduced the retirement lives of certain landing gear components. This new AD retains the requirements of AD 2017-14-03, reduces the retirement lives of additional landing gear components, and requires repeating the inspection. This AD was prompted b…
Airworthiness Directives; Sikorsky Aircraft Corporation
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This AD requires inspecting the engine collective position transducer (CPT). This AD was prompted by reports of wear of the CPT that has resulted in several One Engine Inoperative (OEI) incidents. The actions of this AD are intended to detect and prevent an unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are superseding Airworthiness Directive (AD) 2017-07-02 for Sikorsky Aircraft Corporation (Sikorsky) Model 269D and Model 269D Configuration A helicopters. AD 2017-07-02 required reducing the life limit of and inspecting certain drive shafts. This new AD retains the requirements of AD 2017-07-02 and requires repeating the inspections. The actions of this AD are intended to detect and prevent an unsafe condition o…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, S-76C, and S-76D helicopters. This AD requires inspecting the main rotor (M/R) servo pushrod (pushrod) assembly and applying slippage marks. This AD was prompted by an accident of a Sikorsky Model S-76C helicopter caused by a failed pushrod assembly. The actions of this AD are intended to prevent an un…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires adding operating limitations to a rotorcraft flight manual (RFM). This AD is prompted by test results showing decoupling of the flight director (FD) in certain flight conditions. The actions of this AD are intended to address an unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires installing an engine flame detector bracket assembly and harness assembly. This AD was prompted by reports of false fire warnings. The actions of this AD are intended to prevent an unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires an inspection and reduces the retirement lives of certain landing gear components. This AD is prompted by a revised analysis of the fatigue life of the landing gear. The actions of this AD are intended to prevent an unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires removing from service the tail gearbox center housing (housing) when it has 12,200 or more hours time-in-service (TIS). This AD was prompted by fatigue analysis conducted by Sikorsky that determined the housing required a retirement life. The actions are intended to prevent an uns…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model 269D and Model 269D Configuration A helicopters. This AD requires reducing the life limit of and inspecting certain drive shafts. This AD is prompted by four incidents involving failure of a drive shaft. The actions specified by this AD are intended to prevent the unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are publishing a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires inspecting certain bearings. This AD is prompted by reports of failed bearings with subsequent loss of tail rotor (TR) control. The actions of this AD are intended to address an unsafe condition on these helicopters.
Airworthiness Directives; Sikorsky Aircraft Corporation
We are publishing a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters, which was sent previously to all known U.S. owners and operators of these helicopters. This AD requires inspecting certain bearings. This AD is prompted by a report of a failed bearing. We are issuing this AD to address the unsafe condition on these products.
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation Model S-76D helicopters. This AD requires revising the rotorcraft flight manual (RFM) to prohibit Barometric Altitude Hold (ALT) mode beyond a certain rate of climb or descent. This AD is prompted by a report of the autopilot being unable to maintain level flight during certain flight conditions. The actions specified by this AD are…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires altering the fire bottle inertia switch wiring and performing a cartridge functional test of the fire extinguishing system. This AD was prompted by the inadvertent tripping of inertia-switches that has led to unintentional discharging of the fire bottles, leaving the helicopter's…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are superseding Airworthiness Directive (AD) 2014-07-04R1 for certain Model S-92A helicopters. AD 2014-07-04R1 required repetitive inspections in the upper deck area for incorrectly installed clamps and chafing between the electrical wires and the hydraulic lines and replacing any unairworthy wires or hydraulic lines. This new AD requires altering the wiring system in the upper deck area to correct the unsafe con…
Airworthiness Directives; Sikorsky Aircraft Corporation
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires certain inspections of the main rotor and tail rotor control pushrods (pushrods). This AD is prompted by a Sikorsky investigation that indicated that some pushrods may have incorrectly installed locking mechanisms. These AD actions are intended to detect an incorrectly installed l…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, and S-76C helicopters. This AD requires inspecting the main gearbox (MGB) lower housing jet bores for leaks, paint or caulk blistering, and liner protrusion. This AD was prompted by several reports of MGB low oil pressure warnings which were determined to be the result of unsecured jet bore lin…
Airworthiness Directives; Sikorsky Aircraft Corporation (Type Certificate Previously Held by Schweizer Aircraft Corporation)
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model 269A, 269A-1, 269B, 269C, 269C-1, 269D, and TH-55A helicopters. This AD requires repetitively inspecting and lubricating the tail rotor (T/R) driveshaft splined fittings. This AD was prompted by a report that the T/R driveshaft can disconnect due to deterioration of the splined coupling. The actions are intended to…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are publishing a new airworthiness directive (AD) for Sikorsky Aircraft Corporation Model S-76A, S-76B, S-76C, and S-76D helicopters, which was sent previously to all known U.S. owners and operators of these helicopters. This AD requires inspecting the main rotor (M/R) and tail rotor (T/R) pushrod assemblies and the jamnuts, and applying slippage marks across the pushrod tubes and jamnuts. This AD is prompted by…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Model S-92A helicopters. This AD requires installing a main gearbox (MGB) failed pump sensor and vacuum switch wiring, installing an MGB oil auto bypass system, activating Aircraft Management System (AMS) 7.1 software to show a new visual warning, and installing updated enhanced ground proximity warning system (EGPWS) software that includes an aural ann…
Airworthiness Directives; Sikorsky Aircraft Corporation (Type Certificate Previously Held by Schweizer Aircraft Corporation) Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (type certificate previously held by Schweizer Aircraft Corporation) (Sikorsky) Model 269D and Model 269D Configuration A helicopters. This AD requires reducing the life limit of the ring gear carrier assembly. This AD was prompted by cracks in the ring gear carrier assembly. The actions are intended to reduce the life of the ring g…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are adopting a new airworthiness directive (AD) for certain Sikorsky Model S-76A, B, C, and D helicopters. This AD requires inspecting the tail rotor drive shaft (TDS) flange-to-shaft attachment hardware for correct assembly and correct torque of the fasteners. If there is a discrepancy, this AD requires, before further flight, applying an index mark to the flange and TDS, inspecting the flange and shaft for a cr…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopter. This AD requires revising the Rotorcraft Flight Manual (RFM) to include the appropriate operating limitations for performing Class D external load- combination operations. This AD was prompted by an inaccurate RFM provision, which was approved without appropriate limitations for this model heli…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Model S-92A helicopters. This AD requires, initially and each time the clamps are removed, inspecting for chafing between the electrical wires and the hydraulic lines and, if there is chafing between the wires or lines, before further flight, replacing the unairworthy wires or lines with airworthy wires or lines. Also, this AD requires inspecting each c…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Model S-70, S-70A, and S-70C helicopters. This AD establishes a new life limit based on a prorated formula for certain identified components (parts) installed on Model S-70, S-70A, and S-70C helicopters after being previously installed on certain military model helicopters. This AD was prompted by the discovery that certain parts have been interchanged…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Model S-70, S-70A, S-70C, S-70C (M), and S-70C (M1) helicopters with General Electric (GE) T700-GE-401C or T700-GE-701C engines installed. This AD requires establishing new fatigue life limits for certain GE engine gas generator turbine (GGT) rotor parts. This AD was prompted by a reevaluation of the method for determining the life limit for certain GE…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Model S-76A, B, and C helicopters to require certain inspections of each spindle cuff assembly or blade fold cuff assembly for a crack. If there is a crack, this AD requires replacing the cracked part. If there is no crack, this AD requires applying white paint to the inspection area to enhance the existing inspection procedure. This AD was prompted by…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters to require modifying the No. 1 engine forward firewall center fire extinguisher discharge tube (No. 1 engine tube) and inspecting the outboard discharge tube to determine if it is correctly positioned. This AD was prompted by the discovery that the No. 1 engine tube installed on the helicopters is…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model Helicopters
The FAA is correcting an airworthiness directive (AD) that was published in the Federal Register. The AD applies to all Sikorsky Model S-70, S-70A, and S-70C helicopters, which are restricted category helicopters derived from the military Model UH-60 helicopter. The part number (P/N) for the No. 2 crossfeed breakaway valve listed in the "Required Actions" section is incorrect. This document corrects that error. Also…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-61A, D, E, L, N, NM, R, and V helicopters to require replacing each forward and aft fuel system 40 micron fuel filter element with a 10 micron nominal (40 micron absolute) fuel filter element. This AD was prompted by a National Transportation Safety Board (NTSB) review of in-service events where engine performance…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This AD requires installing an improved throttle stop and a wider trigger on the engine control levers (ECL). This AD was prompted by a bird-strike to the windshield that resulted in unintended movement of the engine control levers from the forward position and towards the flight-idle posi…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires inspecting the tail rotor (T/R) pylon for a loose or missing fastener, a crack, damage, or corrosion and adding an internal doubler to the aft shear deck tunnel assembly. This AD was prompted by the discovery of cracks in T/R pylons. The actions are intended to detect a loose…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A helicopters to require modifying the electric rotor brake (ERB) and inserting changes into the "Normal Procedures" and "Emergency Procedures" sections of the Rotorcraft Flight Manual (RFM). This AD was prompted by a fire in the main gearbox area as a result of a hot electric rotor brake (ERB). The actions are…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires inspecting the main gearbox (MGB) for a crack. This AD is prompted by a crack in the cored passage of the MGB housing, which may be indicated by oil on the housing. These actions are intended to detect a crack in the MGB housing, which could result in loss of oil, failure of the M…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the manufacturer's analysis of engine data that revealed the data was inaccurate in dealing with available above specification engine power margin. This AD requires revising the Operating Limitations section of the Sikorsky Model S-92A Rotorcraft Flight Manual (RFM). The ac…
Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the discovery of tail rotor blade assemblies (blades) manufactured with mislocated aluminum wire mesh, leaving portions of the graphite torque tube (spar) region unprotected from a lightning strike. The actions are intended to detect mislocated blade wire mesh and to preven…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Model S-92A helicopters. This action requires making pen and ink changes, inserting a copy of this AD, or inserting specified temporary revisions into the Limitations section of the Rotorcraft Flight Manual (RFM) limiting the maximum rolling groundspeed for a normal landing or takeoff from 65 knots to 50 knots for helicopters with a certain serial…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters
We are adopting a new airworthiness directive (AD) for the Sikorsky Model S-92A helicopters. This AD requires a nondestructive inspection (NDI), eddy current or fluorescent penetrant inspection (FPI), of each main gearbox (MGB) upper housing assembly rib on the left, right, and forward MGB mounting foot at specified intervals based on the MGB upper housing assembly hours time-in-service (TIS). If there is a crack, t…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S76A, B, and C Helicopters
This amendment supersedes an existing emergency airworthiness directive (EAD) for the specified Sikorsky model helicopters. The EAD requires inspecting the LITEF Attitude Heading and Reference System (AHRS) unit of the navigation system to determine if it is at a Mod Status "18." If either AHRS unit is at Mod Status "18," the EAD requires installing placards on the instrument panel to prohibit single pilot instrumen…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-70A and S-70C Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Model S-70A and S-70C helicopters. This AD requires an ultrasonic test (UT) inspection of the tail gearbox output bevel gear (gear) for a crack. If you find a crack, replacing the gear with an airworthy gear is required before further flight. This AD is prompted by three gear cracking incidents, one of which resulted in the tail rotor separati…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters
This amendment supersedes an existing airworthiness directive (AD) for Sikorsky Model S-92A helicopters that currently requires cleaning and inspecting each main gearbox (MGB) assembly mounting foot pad and rib for a crack and corrosion. If you do not find a crack, the AD requires applying a corrosion preventive compound. If you find a crack, the AD requires replacing the MGB before further flight. If you find corro…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Model S-92A helicopters. The AD requires replacing the main gearbox (MGB) filter bowl assembly with a two-piece MGB filter bowl assembly and replacing the existing mounting studs. The AD also requires inspecting the MGB lube system filters, the housing, the housing threads, and the lockring counterbore and repairing or replacing them as necess…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C helicopters that requires inspecting each installed Woodward HRT (formerly HR Textron) main rotor servo actuator (servo actuator) for a high rate of leakage and replacing each affected servo actuator with a servo actuator containing a newly re-designed servo actuator piston. This amendment is p…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76C Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This action requires inspecting the emergency flotation system squib connector (flotation system connector) to determine if a metallic foil shunt is installed. This amendment is prompted by a discovery that a metallic foil shunt meant to prevent inadvertent activation of a flot…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2009-23-51, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters by individual letters. This AD requires cleaning and inspecting each main gearbox (MGB) assembly mounting foot pad and rib for a crack and corrosion. If you do not find a crac…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Model S-92A helicopters. This action requires a one-time visual inspection of the main gearbox (MGB) lube system filter assembly for oil filter damage. This action also requires if either the primary or secondary oil filter is damaged, replacing both filters, all packings, and the studs before further flight. This AD also requires replacing th…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This amendment supersedes an existing airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. That AD currently requires removing all main gearbox (MGB) filter bowl assembly mounting titanium studs (titanium studs) and replacing them with steel studs. This amendment requires the same actions as the existing AD as well as changes to the Rotorcraft Flight Manual (RFM). This a…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2009-07-53, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters by individual letters. This amendment is prompted by the failure of 2 main gearbox filter bowl assembly studs (studs) that were found broken during a fatal accident investigat…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, and S-61V Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters that requires installing an electric chip detector on each engine and an on-board chip detector annunciation system. The AD also requires revising the Rotorcraft Flight Manual (RFM) to add procedures for crew response to the illumination of an on-board chip detector warning light. Thi…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S92-A Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S92-A helicopters. This action requires, within a specified time, borescope inspecting a certain part-numbered tail rotor pitch change shaft and bearing assembly (shaft and bearing assembly) and also inspecting after any installation. This amendment is prompted by an incident involving failure of a shaft and b…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C helicopters. This action requires a one-time ultrasonic inspection of the main rotor shaft assembly (M/R shaft) for cracking. This amendment is prompted by the discovery of cracking that occurred during the manufacturing of certain M/R shafts. The actions specified in this AD are intended to de…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-61L, N, R, and NM Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters that requires, within a specified time, creating a component history card or equivalent record. The AD also requires recording the hours time-in-service (TIS) and the external lift cycles (lift cycles) for each main gearbox input left and right freewheel unit (IFWU) assembly. Also, th…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires, before further flight, replacing a certain main gearbox (MGB) upper main housing assembly (housing assembly) that has 2700 or more hours time-in-service (TIS) with an airworthy part. This action also requires, before further flight, revising the Airworthiness Limita…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires inspecting each main transmission assembly mounting bolt (bolt) for wear or corrosion, and if wear or corrosion is found, replacing the bolt, bolt barrel nut, and cage. This amendment is prompted by a report of a failure of a bolt that was discovered during…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C helicopters. This action requires certain inspections of the main rotor lower bifilar arm assembly in the attachment area around the lower bifilar lugs for a crack. If a crack is found on any bifilar lug, this AD requires replacing the bifilar arm assembly with an airworthy bifilar arm asse…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires replacing a certain part-numbered tail gear box output housing that has 600 or more hours time-in-service (TIS) with an airworthy part. Also, this AD revises the Airworthiness Limitations section of the maintenance manual by reducing the life limit of the tail gear b…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires replacing the main gearbox (MGB) lubrication/scavenge pump vespel spline adapters (vespel spline adapters) before further flight, and thereafter, replacing them at certain intervals. This amendment is prompted by a reported incident of an in-flight loss of oil pressure.…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-61L, S-61N, S-61-NM, and S-61R Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters that requires installing a Number 5 bearing chip detector in each engine, installing an on-board chip detector annunciation system, and revising the Rotorcraft Flight Manual (RFM) to add procedures for crew response to an on-board chip detector annunciation. This amendment is prompted…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76 A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76 A, B, and C helicopters with dual channel autopilot and dual inverters installed. This action requires a test to determine if the No. 1 inverter is wired to the DC essential bus, and if so, it requires modifying the wiring so that the No. 1 inverter is wired to the No. 2 DC primary bus and the No. 2 inver…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S76A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters that requires removing non-conforming main landing gear brake discs (discs) and replacing them with different part-numbered airworthy discs. It also requires revising the Rotorcraft Flight Manual (RFM) to adjust takeoff and landing distances until the discs are replaced. This amendmen…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, B, and C Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters. This action requires determining the manufacturer of a certain part-numbered rotor brake disc (RBD) and if the manufacturer is Parker Hannifin Corporation (PHC), re-identifying the RBD as appropriate. This action also requires before the first flight of the next day following any day…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B and S-76C Helicopters
This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) model helicopters that requires removing and inspecting each main rotor spindle attachment bolt (bolt) to ensure that the correct bolts are installed. This amendment is prompted by the discovery of improper bolts installed on a helicopter during its production. The actions specified by this AD are inte…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S76A, B, and C Helicopters
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2002-15-51, sent previously to all known U.S. owners and operators of the specified Sikorsky Aircraft Corporation (Sikorsky) helicopters by individual letters. This AD requires, before further flight, identifying and removing any main rotor blade (blade) that has been damaged by lightning and any blade with an unclear…
Airworthiness Directives; Sikorsky Model S-70A and S-70C Helicopters
This amendment supersedes an existing airworthiness directive (AD) for Sikorsky Model S-70A and S-70C helicopters. That AD currently requires inspecting a certain part-numbered main landing gear drag beam (beam) for a crack, removing any cracked beam before further flight, and reducing the torque of the jackpad mounting bolt retention nut (nut) of each beam. This amendment contains the same actions but requires thos…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A Helicopters; Correction
This document corrects an effective date in Airworthiness Directive (AD) 2002-05-06. That AD applies to Sikorsky Aircraft Corporation Model S-76A helicopters and was published in the Federal Register on March 18, 2002 (67 FR 11893). The effective date as stated in paragraph (g) of the AD is incorrect, and this document corrects that effective date. In all other respects, the original document remains the same.
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76B and S-76C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76B and S-76C helicopters. This action requires modifying the electrical power distribution system to change the source of the 28 volts supplied to Nos. 1 and 2 attitude and heading reference (AHRS) WARN circuits. This amendment is prompted by a ground test simulating loss of the essential bus by pulling bot…
Airworthiness Directives; Sikorsky Model S-70A and S-70C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Model S-70A and S-70C helicopters. This action requires certain inspections of each main landing gear drag beam (beam) for a crack and removing any cracked beam before further flight. This action also requires reducing the torque of the jackpad mounting bolt retention nut (nut) of each beam. This amendment is prompted by failure of a beam due to s…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B, and S-76C Helicopters
This amendment supersedes an existing airworthiness directive (AD) that applies to Sikorsky Aircraft Corporation (Sikorsky) Model S- 76A, S-76B, and S-76C helicopters and currently requires, before further flight, performing a fluorescent penetrant inspection (FPI) of the main rotor shaft assembly (shaft). Also, a recurring FPI and visual inspection for a cracked shaft are required by that AD. That AD also requires…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76B and S-76C Helicopters
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2001-03-51, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-76B and S-76C helicopters by individual letters. This AD requires, for certain main rotor shafts, initial and recurring fluorescent penetrant inspections. Replacing each affected main rotor s…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B, and S-76C Helicopters
This document publishes in the Federal Register an amendment adopting superseding Airworthiness Directive (AD) 2000-23-52, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, and S-76C helicopters by individual letters. This AD requires, before further flight, performing a fluorescent penetrant inspection of the main rotor shaft assembly (s…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B, and S-76C Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, and S-76C helicopters. This AD requires initial and repetitive inspections of the main landing gear positioning rod assembly (rod assembly) and the side brace rod end (rod end) for corrosion. If any corrosion is found, this AD requires replacing any part that is corroded with an airworthy part be…
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76 Series Helicopters
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2000-11-52, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-76 series helicopters by individual letters. This AD requires determining the serial number (S/N) of each main rotor blade and removing certain serial numbered main rotor blades. This AD also…
Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-76A Helicopters
This amendment adopts a new airworthiness directive (AD) for Sikorsky Model S-76A helicopters. This AD requires inspecting the air conditioning system at specified intervals until installing a soft- start assembly retrofit kit to prevent a continuous flow of current through the soft-start resistor. This amendment is prompted by a report of overheating of the soft-start assembly. The actions specified by this AD are…
Airworthiness Directives; Sikorsky Model S-61 Helicopters
This amendment supersedes an existing airworthiness directive (AD) for Sikorsky Model S-61 helicopters. That AD requires inspecting certain pylon upper and lower hinge web fittings (web fittings) for corrosion or a crack and either repairing certain web fittings or replacing any unairworthy web fittings with airworthy web fittings. That AD also requires creating a log card or equivalent record and implementing a rec…
Airworthiness Directives; Sikorsky Model S-61 Helicopters
This amendment adopts a new airworthiness directive (AD) applicable to Sikorsky Model S-61 helicopters. This action requires inspecting certain pylon upper and lower hinge web fittings (web fittings) for corrosion or a crack and either repairing certain web fittings or replacing any unairworthy web fittings with airworthy web fittings. The AD also requires creating a log card or equivalent record and implementing a…