Schweizer 269 / 300

Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters (Type Certificate Previously Held by Schweizer Aircraft Corporation)

We are superseding airworthiness directive (AD) 93-17-13 for Schweizer Aircraft Corporation and Hughes Helicopters, Inc. (now Sikorsky Aircraft Corporation) (Sikorsky) Model TH55A, 269A, 269A-1, 269B, and 269C helicopters. AD 93-17-13 required installing tachometer markings and inspecting the lower coupling driveshaft (driveshaft). This new AD requires repetitive inspections of the driveshaft and expands the applicability to include Model 269C-1 helicopters. This AD is prompted by reports of accidents because of driveshaft failures. The actions of this AD are intended to prevent the unsafe condition on these products.

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 detect and prevent excessive wear of the splined coupling, which could lead to failure of the T/R driveshaft and subsequent loss of control of the helicopter.

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 gear carrier assembly to prevent failure of the main rotor transmission, loss of engine power to the main rotor, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation

We are adopting a new airworthiness directive (AD) for the Schweizer Aircraft Corporation (Schweizer) Model 269D and Model 269D Configuration A helicopters. The type certificate for these models is currently held by Sikorsky Aircraft Corporation (Sikorsky). This AD requires inspecting the aft fuselage assembly in the area around the attachment point of the horizontal stabilizer, including the paint, for a crack. This AD also requires inspecting the tailboom interior support structure, and if necessary, installing an inspection panel kit in the aft fuselage assembly, and installing doublers in the stabilizer support brackets. This AD is prompted by reports of loose horizontal stabilizers and cracks in the stabilizer support structure for the extruded tailboom. The actions are intended to prevent separation of the horizontal stabilizer from the helicopter and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation (Schweizer) Model 269A, A-1, B, C, C-1, and TH-55 Series Helicopters

We are superseding an existing emergency airworthiness directive (EAD) for the specified Schweizer model helicopters that was previously sent to all known U.S. owners and operators. That EAD currently requires removing each locknut and verifying sufficient drag torque and retorquing, or if the locknut does not have sufficient drag torque, replacing the locknut with an airworthy locknut. This AD retains the existing EAD requirements but also requires within a specified time, modifying the expandable bolts and installing a cotter pin. This AD is prompted by a locknut working loose from a bolt attaching the tailboom support strut at the aft cluster fitting because the locknut installed on the expandable bolt did not have the proper threads. We are issuing this AD to modify each expandable bolt to allow adding a cotter pin to prevent the strut and driveshaft separating from the helicopter and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation (Schweizer) Model 269D Helicopters

This amendment adopts a new airworthiness directive (AD) for the Schweizer Model 269D helicopters. This action requires installing a Scroll Housing Blade Containment Shielding Kit on each helicopter. This amendment is prompted by 21 reports of the blades of the oil cooler impeller separating, one of which punctured the engine and transmission oil cooler resulting in loss of engine oil pressure. The actions specified in this AD are intended to protect the oil cooler from uncontained oil cooler impeller blades that could damage the oil cooler and result in loss of engine and transmission oil pressure, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269C, C-1, and D Helicopters

This amendment adopts a new airworthiness directive (AD) for the Schweizer Aircraft Corporation (Schweizer) Model 269C, C-1, and D helicopters. This action requires inspecting, modifying, and testing the lateral control trim actuator assembly on certain serial-numbered helicopters. This amendment is prompted by three reported incidents of the inner spring tube separating from the lateral trim control housing resulting in a lateral cyclic control restriction. The actions specified in this AD are intended to prevent separation of the inner spring tube from the lateral trim control housing and the associated loss of trim control, increased local resistance to right cyclic stick movement, and an emergency landing or subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C, and TH-55A Helicopters

This amendment revises an existing airworthiness directive (AD), for the specified Schweizer Aircraft Corporation (Schweizer) model helicopters, that currently requires inspecting the lugs on certain aft cluster fittings and each aluminum end fitting on certain tailboom struts. Modifying or replacing each strut assembly within a specified time period and serializing certain strut assemblies are also required. Additionally, a one-time inspection and repair, if necessary, of certain additional cluster fittings, and replacement and modification of certain cluster fittings within 150 hours time-in- service (TIS) or 6 months, whichever occurs first, is required. This amendment requires the same actions as the existing AD, but revises the Applicability section of the AD. This amendment is prompted by the discovery of an error in the Applicability section of the existing AD. The actions specified by this AD are intended to prevent failure of a tailboom support strut or a cluster fitting, which could cause rotation of a tailboom into the main rotor blades, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C, and TH-55A Helicopters

This amendment supersedes an existing airworthiness directive (AD), applicable to Schweizer Aircraft Corporation (Schweizer) Model 269A, 269A-1, 269B, 269C, and TH-55A helicopters, that currently requires inspecting the lugs on certain aft cluster fittings and each aluminum end fitting on certain tailboom struts. Modifying or replacing each strut assembly within a specified time period and serializing certain strut assemblies are also required by the existing AD. This amendment requires the same actions as the existing AD, and also requires a one-time inspection and repair, if necessary, of certain additional cluster fittings, and replacement and modification of certain cluster fittings within 150 hours time-in-service (TIS) or 6 months, whichever occurs first. This amendment is prompted by the need to expand the applicability to include certain Hughes-manufactured cluster fittings and to provide a terminating action for the repetitive dye-penetrant inspections of the cluster fittings. The actions specified by this AD are intended to prevent failure of a tailboom support strut or a cluster fitting, which could cause rotation of a tailboom into the main rotor blades, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269D Helicopters

This amendment adopts a new airworthiness directive (AD) for Schweizer Aircraft Corporation (Schweizer) Model 269D helicopters. This action requires inspecting each aluminum horizontal stabilizer endplate (endplate) and the attach angles for cracks, fretting, and endplate bending. If fretting is found, as indicated by a powder residue adjacent to a rivet head, installing an inspection hole in the horizontal stabilizer and inspecting the internal structure is required. Replacing unairworthy parts is required before further flight. Finally, reporting any cracked or bent endplate, any cracked attach angles, or fretting to the FAA is required. This amendment is prompted by reports of loose endplates, and one report of an endplate separating from the helicopter during flight. The actions specified in this AD are intended to prevent loss of an endplate during flight, which could strike the tail rotor and result in loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C, and TH-55A Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2001-25-52, which was sent previously to all known U.S. owners and operators of Schweizer Aircraft Corporation (Schweizer) Model 269A, 269A-1, 269B, 269C, and TH-55A helicopters by individual letters. This AD supersedes an existing AD that requires inspecting and modifying or replacing, if necessary, the aluminum end fittings of each tailboom support strut (strut). That AD also requires inspecting the tailboom center attach fittings and center frame aft cluster fittings for damage, and if damaged parts are found, replacing the damaged parts. This AD requires inspecting and replacing, if necessary, each strut clevis lug (lug) on each tailboom center frame aft cluster fitting (cluster fitting), certain strut assemblies, certain tailboom attachments, and certain frame aft cluster fittings. Modifying or replacing each strut assembly within a certain time period and serializing certain strut assemblies are also required. This AD is prompted by an accident in the United Kingdom involving the in-flight structural failure of a Schweizer Model 269C helicopter. The actions specified by this AD are intended to prevent failure of a lug on a cluster fitting, rotation of a tailboom into the main rotor blades, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C, 269C-1, 269D, and TH-55A Helicopters

This amendment supersedes an existing airworthiness directive (AD) that applies to Schweizer Aircraft Corporation (Schweizer) Model 269A, 269A-1, 269B, 269C, 269C-1, 269D helicopters. That AD requires inspecting the tail rotor swashplate shaft (shaft) nut for looseness and, if loose, inspecting the shaft for proper size; subsequently inspecting the shafts not previously inspected; and replacing any undersized shaft prior to further flight. This amendment reduces the applicability by specifying certain serial number tail rotor pitch control (pitch control) assemblies and shipping dates but adds the Schweizer Model TH-55A helicopter to the applicability. This amendment is prompted by the discovery of an undersized replacement shaft during routine maintenance. The actions specified by this AD are intended to prevent failure of the shaft, loss of the tail rotor, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C, 269C-1, and 269D Helicopters

This amendment adopts a new airworthiness directive (AD) applicable to Schweizer Aircraft Corporation (SAC) Model 269A, 269A-1, 269B, 269C, 269C-1, and 269D helicopters. This action requires inspecting the tail rotor swashplate shaft (shaft) nut for looseness and, if loose, inspecting the shaft for proper size; subsequently inspecting the shafts not previously inspected; and replacing any undersized shaft prior to further flight. This amendment is prompted by the discovery of an undersized replacement shaft during routine maintenance. The actions specified in this AD are intended to prevent failure of the shaft and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269C-1 Helicopters

This amendment adopts a new airworthiness directive (AD), applicable to Schweizer Aircraft Corporation Model 269C-1 helicopters, that requires a visual inspection of the bond line between the main rotor blade (blade) abrasion strip (abrasion strip) and the blade for voids, separation, or lifting of the abrasion strip; a visual inspection of the adhesive bead around the perimeter of the abrasion strip for erosion, cracks, or blisters; a tap (ring) test of the abrasion strip for debonding or hidden corrosion voids; and removal of any blade with an unairworthy abrasion strip and replacement with an airworthy blade. This amendment is prompted by four reports that indicate that debonding and corrosion have occurred on certain blades where the abrasion strip attaches to the blade skin. The actions specified by this AD are intended to prevent loss of the abrasion strip from the blade and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269D Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-26-06 which was sent previously to all known U.S. owners and operators of Schweizer Aircraft Corporation (Schweizer) Model 269D helicopters by individual letters. This AD requires removing the main rotor drive shaft (shaft) and inspecting it for cracks. If a crack is found, replacing the shaft with an airworthy shaft is required. This AD also requires periodically verifying the torque of the main rotor hub (hub) bolts. This amendment is prompted by four reports of cracking in the shaft of helicopters with a large diameter hub. Wear patterns indicate cracking was caused by loss of clamping torque on the hub and shaft assembly due to the use of grease between the hub and shaft. This condition, if not corrected, could result in failure of the shaft and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, 269D, and TH- 55A Helicopters

This amendment adopts a new airworthiness directive (AD), applicable to Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, 269D, and TH-55A helicopters, that requires a visual inspection of the bond line between the main rotor blade abrasion strip (abrasion strip) and the blade for voids, separation, or lifting of the abrasion strip; a visual inspection of the adhesive bead around the perimeter of the abrasion strip for erosion, cracks, or blisters; a tap (ring) test of the abrasion strip for evidence of debonding or hidden corrosion voids; and removal of any blade with an unairworthy abrasion strip and replacement with an airworthy blade. This amendment is prompted by four reports that indicate that debonding and corrosion have occurred on certain blades where the abrasion strip attaches to the blade skin. The actions specified by this AD are intended to prevent loss of the abrasion strip from the blade and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation Model 269A, A-1, B, and C, and TH-55A Helicopters

This amendment adopts a new airworthiness directive (AD), applicable to Schweizer Aircraft Corporation Model 269A, A-1, B, and C, and TH-55A helicopters, with a certain main rotor transmission ring gear (ring gear) installed, that requires inspections of the ring gear teeth for surface deterioration which includes pitting, excessive wearing, cracking or corrosion, and replacement of the ring gear if such ring gear teeth surface deterioration is found; and also requires creating a main rotor transmission component log card (log card), if none is available, and making a notation on the log card if a ring gear is changed. This amendment is prompted by reports of failures of the ring gear due to single tooth distress as a result of improper gear tooth spacing during the manufacturing of the ring gear. The actions specified by this AD are intended to prevent failure of the ring gear, loss of drive to the main rotor gearbox, and a subsequent forced landing.

Airworthiness Directives; Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, and TH-55A Helicopters

This amendment supersedes an existing airworthiness directive (AD), applicable to Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269A-2, and 269B helicopters, that currently requires initial and repetitive inspections of the main rotor thrust bearing (bearing) for bearing rotational roughness, corrosion, inadequate lubrication, physical damage, or excessive zinc chromate paste or moisture. This amendment requires the same initial and repetitive inspections required by the existing AD, but would extend the retirement life for certain bearings, and would remove the Model 269A-2 helicopter from, and add the Model TH-55A helicopters to the applicability of this AD. This amendment is prompted by an FAA analysis of service information issued by the manufacturer that extends the retirement life for certain bearings. The actions specified by this AD are intended to prevent failure of the bearing, loss of the main rotor, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A Helicopters

This amendment supersedes an existing airworthiness directive (AD), applicable to Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A helicopters with certain main rotor (M/R) drive shafts installed, that currently requires a one-time radiographic inspection or other non- destructive inspection of certain M/R drive shafts for cracks, distortion, corrosion, or other surface damage, at specified time intervals or upon the occurrence of specified conditions. This amendment requires the same inspections as the previous AD, but expands the applicability of certain inspections to additional models of the affected helicopters, and excludes certain M/R drive shafts from certain inspections. This amendment is prompted by a reevaluation as a result of a comment to the previous AD suggesting the need to expand the applicability of certain inspections to additional models of the affected helicopters and to exclude certain M/R drive shafts from certain inspections. The actions specified by this AD are intended to prevent structural failure of the M/R drive shaft, separation of the M/ R from the helicopter, and subsequent loss of control of the helicopter.

Airworthiness Directives; Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A Series Helicopters

This amendment supersedes an existing airworthiness directive (AD), applicable to Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A series helicopters, that currently requires an initial and repetitive visual inspection of the clutch control spring assembly for component wear and replacement of affected unairworthy parts. This amendment requires the same initial and repetitive visual inspection and replacements required by the existing Priority Letter AD, but references a revised service bulletin and provides replacement procedures for the aluminum spring retainer thermofit tube (plastic sleeve). This amendment is prompted by a recent accident involving a Model 269C helicopter that reportedly lost engine drive power at 100 feet above ground level (AGL) with a resulting unsuccessful autorotative landing, and the manufacturer's issuance of revised service information that provides more detailed instructions for replacement of two components of the belt drive clutch control assembly. The actions specified by this AD are intended to prevent failure of the aluminum spring retainer, loss of power to the rotor drive system, and a subsequent forced landing.