Results
98-06-37: This amendment adopts a new airworthiness directive (AD) that applies to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes. This AD requires replacing any tow release cable assembly that does not have a swivel-type end with a cable assembly that does have a swivel-type end. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this AD are intended to prevent the inability to release the tow rope because of the design of the cable assembly, which could result in loss of control of the sailplane during towing operations.
2011-27-03: We are adopting a new airworthiness directive (AD) for all Model 737 airplanes. This AD was prompted by a report of extensive corrosion of a ballscrew used in the drive mechanism of the horizontal stabilizer trim actuator (HSTA). This AD requires repetitive inspections, lubrications, and repetitive overhauls of the ball nut and ballscrew and attachment (Gimbal) fittings for the trim actuator of the horizontal stabilizer; various modification(s); and corrective actions if necessary; as applicable. We are issuing this AD to prevent an undetected failure of the primary load path for the ballscrew in the drive mechanism of the HSTA and subsequent wear and failure of the secondary load path, which could lead to loss of control of the horizontal stabilizer and consequent loss of control of the airplane.
66-27-02: 66-27-02 BOEING: Amdt. 39-303 Part 39 Federal Register November 9, 1966. Applies to Model 707-300, -300B, -300C, and -400 Series Airplanes.\n \n\tCompliance required as indicated.\n \n\tTo detect cracks of the elevator nose structure in the outboard balance bay, accomplish the following:\n \n\t(a)\tWithin the next 800 hours' time in service after the effective date of this AD, unless accomplished within the last 800 hours' time in service, and thereafter at intervals not to exceed 1,600 hours' time in service from the last inspection until modified in accordance with (h), inspect elevators of Model 707-300 and -400 Series airplanes with 20,000 or more hours' time in service on the effective date of this AD, and elevators of Model 707-300B Series airplanes with 12,000 or more hours' time in service on the effective date of this AD in accordance with (f).\n \n\t(b)\tWithin the next 200 hours' time in service after the effective date of this AD, unless accomplished within the last 200 hours' time in service, and thereafter at intervals not to exceed 400 hours' time in service from the last inspection until modified in accordance with (h), inspect elevators of Model 707-300C Series airplanes with 2,000 or more hours' time in service on the effective date of this AD in accordance with (f). \n\n\t(c)\tBefore the accumulation of 20,800 hours' time in service and thereafter at intervals not to exceed 1,600 hours' time in service from the last inspection until modified in accordance with (h), inspect elevators of Model 707-300 and -400 Series airplanes with less than 20,000 hours' time in service on the effective date of this AD in accordance with (f).\n \n\t(d)\tBefore the accumulation of 12,800 hours' time in service and thereafter at intervals not to exceed 1,600 hours' time in service from the last inspection until modified in accordance with (h), inspect elevators of Model 707-300B Series airplanes with less that 12,000 hours' time in service on the effective date of this ADin accordance with (f). \n\n\t(e)\tBefore the accumulation of 2,200 hours' time in service and thereafter at intervals not to exceed 400 hours' time in service from the last inspection until modified in accordance with (h), inspect elevators of Model 707-300C Series airplanes with less than 2,000 hours' time in service on the effective date of this AD in accordance with (f).\n \n\t(f)\tVisually inspect for cracks in the leading edge of the elevators in bays No. 4 and No. 5 in accordance with paragraph 3, Part I, Boeing Service Bulletin No. 2386 (R-1), or later FAA- approved revision, except that the initial inspection of Bay No. 4 need not be accomplished until the next repetitive inspection of Bay No. 5 is required, if Bay No. 5 has been inspected in accordance with this paragraph.\n \n\t(g)\tIf cracks are found during the inspections specified in (f), before further flight, repair or replace cracked parts in accordance with the FAA-approved Structural Repair Manual or repair the elevatorin accordance with paragraph 3, Part II, Boeing Service Bulletin No. 2386(R- 1), or later FAA-approved revision or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\t(h)\tAfter the elevators have been modified in accordance with paragraph 3, Part II, Boeing Service Bulletin No. 2386(R-1) or later FAA-approved revision or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region, the repetitive inspections required by this AD may be discontinued.\n \n\t(i)\tUpon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance of an established inspection period of the operator, if the request contains substantiating data to justify the increase for that operator.\n \n\tThis directive effective November 9, 1966.
2011-27-06: We are adopting a new airworthiness directive (AD) for certain Dassault Aviation Model FALCON 7X airplanes equipped with certain ram air turbine (RAT) transformer rectifier units (TRUs). This AD was prompted by a report of incorrect design of the TRU part of the RAT system. This AD requires replacing any affected RAT TRU with a modified RAT TRU. We are issuing this AD to prevent loose internal wiring in the RAT generator, which could result in degraded direct current power to essential airplane systems while the RAT is deployed, which could adversely affect continued safe flight and landing of the airplane.
2010-06-12R1: We are revising an existing airworthiness directive (AD) for Thielert Aircraft Engines GmbH models TAE 125-02-99 and TAE 125-01 reciprocating engines. That AD currently requires replacing the existing rail pressure control valve with an improved rail pressure control valve. This new AD requires the same actions but relaxes the initial compliance time from within 100 flight hours to within 600 flight hours for TAE 125-01 reciprocating engines. This AD was prompted by the determination that our AD was inadvertently more restrictive than European Aviation Safety Agency AD 2008-0128. We are issuing this AD to prevent engine in-flight shutdown, possibly resulting in reduced control of the aircraft.
69-05-01 R2: 69-05-01 R2 DE HAVILLAND: Amendment 39-728 as amended by Amendment 39-1175 is further amended by Amendment 39-3824. Applies to de Havilland DHC-6 airplanes certificated in all categories: (a) Prior to next flight unless accomplished within the last 50 hours time in service, and at intervals thereafter not to exceed 100 hours time in service from the last inspection, visually inspect the control column lower sub-assembly, P/N C3CF39-17 for cracks. Replace cracked parts before further flight with a part of the same part number or with an equivalent part approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (b) The repetitive inspection interval required by (a) may be increased by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region upon receipt of substantiating data submitted through an FAA maintenance inspector. (c) Report the results of the initial inspection findings required by this AD to the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region (reporting approved by the Bureau of the Budget under B.O.B. No. 04-R0174). (d) Cracked parts, P/N C3CF39-17, may be replaced with a new sub-assembly, P/N C3CF39-19, in accordance with De Havilland Modification No. 6/1433 in De Havilland Service Bulletin (S/B) No. 6/180, Revision D, dated April 30, 1976, ACCOMPLISHMENT INSTRUCTION No. 5, or with an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (e) The repetitive inspection required by (a) may be discontinued when the lower sub-assembly is replaced by P/N C3CF39-19 in accordance with De Havilland Modification No. 6/1433, or FAA approved equivalent. Amendment 39-728 effective March 5, 1969, and was effective upon receipt for all recipients of the telegram dated January 31, 1969 which contained this amendment. Amendment 39-1175 was effective March 23, 1971. This Amendment 39-3824 becomes effective July 7, 1980.
2011-26-09: We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. This AD was prompted by reports of excessive in- service wear damage of the thumbnail fairing edge seal, and of the panel rub strip and skin assembly of the fan cowl. This AD requires replacement of the thumbnail fairing edge seals on both sides of the engines with Nitronic 60 stainless steel alloy seals. We are issuing this AD to prevent failure of the fire seal, which could allow a fire in the fan compartment to spread beyond the firewall and reach the flammable fluid leakage zones, resulting in an uncontrolled fire.
2011-26-06: We are adopting a new airworthiness directive (AD) for Airbus Model A330-200 and -300 series airplanes, Model A340-200 and -300 series airplanes, and Model A340-500 and -600 series airplanes. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: During a pre-flight test before delivery of an aeroplane from the Airbus production line, a fault message was triggered on FDU1 [fire detection unit]. Investigations by the supplier on the faulty FDU have identified a soldering quality issue on one of the internal cards. This quality issue resulted from a specific repair process that was applied to some FDU * * * during manufacturing. The FDU monitors the engine, Auxiliary Power Unit (APU) and Main Landing Gear (MLG) bay fire detection systems. This condition, if not corrected, may adversely affect the fire detection system performance in case of a fire in the area that is monitored by the faulty FDU, potentially resulting in an unsafe condition. * * * * * We are issuing this AD to require actions to correct the unsafe condition on these products.
66-04-03: 66-04-03 SIKORSKY: Amdt. 39-194 Part 39 Federal Register February 12, 1966, as amended by Amendment 39-1563 is further amended by Amendment 39-2577. Applies to Models S-55 Series and S-62A Helicopters. Compliance required as indicated. To prevent operation with fatigue cracks in the spar of a main rotor blade, accomplish the following: (a) Except as provided in (e), remove from service S14-10-2100 series main rotor blades with 2,225 or more hours' time in service on the effective date of this AD within the next 25 hours' time in service. (b) Except as provided in (e), remove from service S14-10-2100 series main rotor blades with less than 2,225 hours' time in service on the effective date of this AD before the accumulation of 2,250 hours' time in service. (c) Except as provided in (e), remove from service S14-10-2201 series main rotor blades with 2,100 or more hours' time in service on the effective date of this AD within the next 150 hours' time in service. (d) Except as provided in (e), remove from service S14-10-2201 series main rotor blades with less than 2,100 hours' time in service on the effective date of this AD before the accumulation of 2,250 hours' time in service. (e) The service life limits specified in (a), (b), (c), and (d) may be extended to 6,000 hours' total time in service for S14-10-2201-9 main rotor blades and S14-10-2100 series and S14- 10-2201 series blades modified to S14-10-2201-9 blades, provided the blades are inspected at the times and in the manner set forth in Sikorsky Service Bulletin No. 55B10-7E dated March 26, 1976 or No. 62B10-6E dated March 26, 1976 or later FAA approved revisions, as applicable, and, if low pressure is indicated, the cause is determined and corrected before further flight in accordance with the applicable service bulletin. Amendment 39-194 became effective February 12, 1966. Amendment 39-1563 became effective November 30, 1972. This Amendment 39-2577 becomeseffective April 27, 1976.
2011-06-06 R1: We are revising an existing airworthiness directive (AD) that applies to all Eclipse Aerospace, Inc. Model EA500 airplanes equipped with Pratt & Whitney Canada, Corp. (P&WC) Model PW610F-A engines. The existing AD currently requires incorporating an operating limitation of a maximum operating altitude of 30,000 feet into Section 2, Limitations, of the airplane flight manual (AFM). Since we issued that AD, P&WC has developed a design change for the combustion chamber liner assembly. This new AD retains the requirements of the current AD, clarifies the engine applicability, and allows the option of incorporating the design change to terminate the current operating limitation and restore the original certificated maximum operating altitude of 41,000 feet. We are issuing this AD to correct the unsafe condition on these products.
2011-26-03: We are superseding an existing airworthiness directive (AD) for certain Model 777-200, -300, and -300ER series airplanes. That AD currently requires installing Teflon sleeving under the clamps of certain wire bundles routed along the fuel tank boundary structure, and cap sealing certain penetrating fasteners of the main and center fuel tanks. This AD expands the applicability in the existing AD. This AD was prompted by fuel system reviews conducted by the manufacturer, which determined that electrical arcing on the fuel tank boundary structure or inside the fuel tanks could result in a fire or explosion. We are issuing this AD to correct the unsafe condition on these products.
52-01-02: 52-01-02 BELL: Applies to All Models 47B, and 47B3 Helicopters and to Model 47D Helicopters Serial Numbers 1 to 79, Inclusive. Compliance required at next 300-hour overhaul, but not later than March 1, 1952. To increase the safety of the main rotor blade equalizer horns and drag brace fittings, which have failed in accidents involving damage to the main rotor, replace the existing equalizer horn (P/N 47-120-027-2) and drag brace fitting (P/N 47-110-145-2) with revised parts P/N 47- 120-167-1 and P/N 47-110-235-1, respectively. (Bell Service Bulletin No. 77 covers this same subject.)
59-16-04: 59-16-04 SIKORSKY: Amendment 34 (24 F.R. 6581) as amended by Amendment 39-2140. Applies to all model S-58 helicopters including military types HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, VH-34D, except for those modified in accordance with Sikorsky Modification Kit, P/N S1607-5695-1. Compliance required as indicated. Due to the present design of the damper trunnion assembly, torque cannot be maintained on the bolt, thereby leading to fretting and fatiguing of the bolt. Although this problem has been partially corrected by replacing the AN 177-34 bolt with S1610-23198 bolt (NAS 627-48 bolt with cotter pin hole), working of the bolt in the assembly has not been completely eliminated. Accordingly, it is considered essential that close surveillance be maintained and the following inspection be carried out pending the development and installation of aredesigned trunnion assembly to correct this difficulty. During the 50-hour periodic inspection of the damper trunnion for freedom per item No. 20(c) of the Periodic Inspection Check Sheet, Airframe System S-58 Maintenance Manual, remove the damper trunnion bolt P/N S1610-23198 and inspect for condition. If indications of wearing, scouring or fretting are found the bolt must be replaced prior to further flight. This amendment 39-2140 becomes effective April 8, 1975.
2011-26-01: We are adopting a new airworthiness directive (AD) for Piaggio Aero Industries S.p.A. Model P-180 airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as the baggage door lockpins not engaging properly and the baggage door open light illuminating when the baggage door is not open, which could lead to the pilot disregarding a valid warning. We are issuing this AD to require actions to address the unsafe condition on these products.
2011-25-08: We are adopting a new airworthiness directive (AD) for International Aero Engines (IAE) V2500-A1, V2522-A5, V2524-A5, V2525- D5, V2527-A5, V2527E-A5, V2527M-A5, V2528-D5, V2530-A5, and V2533-A5 turbofan engines. This AD was prompted by three reports of high- pressure turbine (HPT) case burn-through events, numerous reports of loss of stage 1 blade outer air seal segments, and HPT case bulging. This AD requires initial and repetitive 360 degree borescope inspections of HPT stage 1 blade outer air seal segments for evidence of certain distress conditions. This AD also requires incorporation of improved durability stage 1 blade outer air seal segments at the next exposure to the HPT module subassembly as terminating action to the repetitive inspections. We are issuing this AD to prevent HPT case burn-through, uncontrolled under-cowl engine fire, and damage to the airplane.
59-20-04: 59-20-04\tBOEING: Applies to the following 707-100 series aircraft only: Serial Numbers 17586 through 17591, 17609 through 17612, 17628 through 17652, 17658 through 17672, 17696 through 17702, 17925 through 17927. \n\tCompliance required not later than November 15, 1959. \n\tThere have been failures of the welded flanges located at each end of the turbocompressor bleed duct mounted on the high pressure bleed port of the engine. These failures have caused damage to the surrounding structure due to excessive pressure and temperature in the cowl and also required engine shutdown due to high EGT and low EPR. Therefore, the following modification(s) shall be accomplished as indicated: \n\t(a)\tAn additional filetweld shall be added to the external side of the three flanges on the turbocompressor engine bleed duct assembly. (Each pod utilizing a turbocompressor.) \n\t(b)\tThe existing boss weld on the turbocompressor engine bleed duct shall be strengthened by welding gussets to both the boss and duct. These gussets are to be fabricated in accordance with Boeing Service Bulletin No. 543 figure 2. \n\tNOTE: The above modification(s) are included in Boeing Airplane Company Service Bulletin No. 543 dated August 14, 1959.
52-16-01: 52-16-01 MARTIN: Applies to All Model 202A Airplanes. Item I is to be accomplished by means of a progressive modification program to be submitted to and approved by the FAA. The program shall begin no later than August 10, 1952, and shall be completed no later than May 1, 1953. I. In order to prevent inadvertent actuation of the propeller reversing solenoid valves, Protect the reversing solenoid circuits from all other electrical circuits and protect the reversing solenoid circuits from each other. This is to be accomplished in accordance with Attachment A (see AD 52-13-02 Lockheed) and the following instructions which pertain to specific features to be considered in isolation of the circuits. Other features which are not specifically referred to in this list shall be treated in an equivalent manner. A. Comply with TWA Engineering Orders 5686, 5776, and 5887. B. Modify the 19 pin connector at the propeller control relay box as specified in item 2 of attachment A. C. Modify the Hamilton Standard relay box on the front of the control pedestal to shield the reversing solenoid relay contacts, etc., from all other circuits which are energized at any time except when reversing is desired. Reversing relay boxes which have separate pin connectors for the reversing solenoid wire and the remaining circuits, shall be so installed that it will not be possible inadvertently to interchange any connectors between the relay boxes. D. Modify the configuration of the propeller control relay box in a manner equivalent specified in item I.C. E. Modify reversing solenoid circuit wiring in accordance with item 4 of attachment A. II. The following maintenance practices are to be instituted not later than August 10, 1952. A. At each nearest scheduled service to 350 hours: (1) Inspect all points covered by TWA Engineering Orders 5686 and 5776. (2) Perform an electrical check of the reverse safety switches in the pedestal assembly to assure that the switch is open when the throttles are moved forward out of the reverse position, unless it is shown that failure of any of the reverse safety switches to open will be clearly apparent to the flight crew by reason of improper operation of the propeller control system. Because of the many technical considerations involved, analyses showing that the objective of this revision has been accomplished should be referred to the FAA for engineering evaluation and approval. B. At any time that an electrical fault occurs in a circuit which is carried in the same bundles or the same conduits as the reversing solenoid circuit, representative terminal points in the faulty circuit are to be inspected to determine whether any damage may have occurred within the bundles or conduit. If there is evidence of possible damage, all the wiring involved is to be removed and inspected. Damaged wiring is to be replaced as necessary. III. Operating instructions: Comply with item 5 of attachment A. IV. (Note: Propeller governor design changes which are under development and whose purpose is to provide a high pressure hydraulic circuit bypass to safeguard against inadvertent reversing and to provide ability to feather even when the reversing solenoid is energized, are still under consideration and may be the subject of a future directive.)
2011-25-09: We are adopting a new airworthiness directive (AD) for certain PW4000 turbofan engines. This AD was prompted by an updated low-cycle fatigue (LCF) life analysis performed by PW. This AD requires removing certain part number (P/N) high-pressure turbine (HPT) stage 1 and HPT stage 2 airseals and HPT stage 1 airseal rings before their published life limit and establishes a new lower life limit for these parts. We are issuing this AD to prevent failure of these parts, which could lead to an uncontained engine failure and damage to the airplane.
2011-21-18: This amendment adopts a new airworthiness directive (AD) for the Eurocopter France Model EC 120B helicopters. This AD requires modifying the pilot cyclic control friction device by replacing a certain thrust washer with two thrust washers. This AD is prompted by an incident in which the pilot encountered a sudden restriction of the cyclic control movement during flight. The actions specified by this AD are intended to prevent jamming of a pilot cyclic control stick and subsequent loss of control of the helicopter.
53-23-02: 53-23-02 de HAVILLAND: Applies to Model DHC-2 (Beaver) Aircraft, Serial Numbers 164 to 407 Inclusive. Compliance required not later than December 15, 1953. When filling the fuel tanks, it is possible for spilled fuel to seep down between the fuel tank filler neck recess box and the aircraft's outer skin. This permits gasoline fumes to accumulate in the tank bays beneath the floor and can create a fire hazard. The aircraft should be inspected to ascertain if a satisfactory seal exists between the filler neck recess box (C2-FS-1005ND) and the outer skin (C2-S-829ND). If seal is unsatisfactory, fill gap with either "Goodyear Plyabond" or "Minneapolis Mining EC776" metal sealing compounds or equivalent. In the interim, until resealing is accomplished, a "No Smoking" placard should be installed in the cabin. The FAA concurs in this mandatory action by the Canadian Department of Transport. (de Havilland Technical News Sheet No. 68, Series B, dated September 15, 1953,covers this same subject and provides resealing instructions.)
2011-24-12: We are superseding an existing airworthiness directive (AD) for certain Model 737-300, -400, and -500 series airplanes. That AD currently requires repetitive external non-destructive inspections to detect cracks in the fuselage skin along the chem-mill step at stringers S-1 and S-2 right, between station (STA) 827 and STA 847, and repair if necessary. This new AD adds inspections for cracking in additional fuselage crown skin locations, and repair if necessary. This new AD also reduces the inspection thresholds for certain airplanes, extends certain repetitive inspection intervals, and adds airplanes to the applicability of the existing AD. This AD was prompted by reports of additional crack findings of the fuselage crown skin at the chem- milled steps. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin panels at the chem-milled steps, which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of the airplane.
2011-24-11: We are adopting a new airworthiness directive (AD) for certain Honeywell International Inc. ALF502L-2C, ALF502R-3, ALF502R-3A, ALF502R-5, LF507-1F, and LF507-IH turbofan engines. This AD requires removing from service certain second stage high pressure compressor (HPC2) discs. This AD was prompted by a report of cracks found in an HPC2 disc during routine inspection. We are issuing this AD to prevent the affected discs from fracturing before reaching the currently published life limit. A disc fracture could result in an uncontained failure of the disc and damage to the airplane.
55-22-04: 55-22-04 VICKERS-ARMSTRONG: Applies to All Viscount Model 745D Aircraft. Compliance required as indicated. Cracks have been found in the tailplane center section main spar extending along the lines of rivets attaching the web plate. Accordingly, Vickers-Armstrong (Aircraft) Ltd. issued Preliminary Technical Leaflet No. 52 dated August 19, 1955, covering this subject. The British Air Registration Board considers Modification D.1384, the initial and repetitive inspections recommended therein mandatory in which the FAA concurs. Aircraft complying with the limitations specified in PTL No. 52 will be considered serviceable.
58-09-01: 58-09-01 BELL: Applies to Model 47J Helicopters. Compliance required prior to next flight. 1. All 47-110-401-13 main rotor blades known to have hit an object, or to have contacted the universal joint cover on the tail boom causing an indentation over 1/4-inch deep in the universal joint cover, must be removed from service for further detail inspection, and repair if necessary. Such internal inspections and repairs are to be made by the blade manufacturer. 2. Visually inspect the stainless steel leading edge of the -13 blades for cracks and remove cracked blades. No field repairs are authorized. Cracked blades are to be returned to the blade manufacturer for detail inspection and repair. 3. Remove all 47-110-401-9 main rotor blades. These blades must be reworked to the -13 configuration prior to return to service. CAA telegraphic instructions of April 28, 1958, covered this subject.
2011-24-03: We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: There has been one reported incident where the main landing gear (MLG) failed to extend during testing of the MLG alternate release system. Investigation revealed that the door release lever bushing was worn, causing an increase in the lateral movement of the release cable system. An increase in free-play within the release cable system would cause additional wear to the door release lever bushing and may lead to the turnbuckle fouling against the nacelle frame. The bushing wear at the door release lever and turnbuckle fouling could cause a failure in the alternate release system, preventing the landing gear from extending in the case of a failure of the normal MLG extension/retraction system. * * * * * The unsafe condition is loss of control during landing. We are issuing this AD to require actions to correct the unsafe condition on these products.