17 Airworthiness Directives: 12 airplane, 1 rotorcraft, 3 engine, 1 propeller.
AD 97-11-14 · published Jun 3, 1997, effective Jul 8, 1997
British Aerospace Model BAC 1-11 200 and 400 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace Model BAC 1-11 200 and 400 series airplanes, that requires inspections of the main landing gear (MLG) A-frame attachment fittings to detect corrosion or cracking, and repair or replacement of cracked or corroded components with new components. This amendment is prompted by findings of corroded and cracked A-frame components of the MLG. The actions specified by this AD are intended to prevent corrosion and cracking of MLG A-frame components, which could result in collapse of the MLG.
AD 97-12-01 · published Jun 4, 1997, effective Jun 19, 1997
Cessna Model 650 Airplanes
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Cessna Model 650 airplanes. This action requires inspections to detect discrepancies of a certain wire bundle assembly and to detect discrepancies of the hydraulic pump suction line in the area above the baggage compartment; and corrective actions, if necessary. This AD also requires modification of the supports for the wire bundle cable assembly and the supports for the hydraulic pump suction line. This amendment is prompted by a report that, due to inadequate clearance, an alternating current (AC) wire chafed against the hydraulic pump suction line and caused electrical arcing. The actions specified in this AD are intended to prevent such electrical arcing and consequent fire hazard.
AD 97-12-03 · published Jun 9, 1997, effective Jun 24, 1997
Boeing Model 747 Series Airplanes
This amendment supersedes two existing airworthiness directives (AD) that are applicable to certain Boeing Model 747 series airplanes. One of those AD's currently requires inspections for cracking, corrosion, and fracturing of the lower horizontal clevis of the strut midspar fittings, and replacement of discrepant parts with new or serviceable parts, or repair, if necessary. That AD also requires inspection for removal of broken sealant of the clevis and the fasteners, and various follow-on actions. It also provides for optional terminating actions for the inspections. The other AD currently requires inspection for cracking of certain fastener holes of the upper and lower horizontal clevis legs. This amendment continues to require inspections to detect cracking, corrosion, and fracturing of the lower horizontal clevis; and adds corresponding inspections of the upper horizontal clevis, and replacement of discrepant parts with new parts, or rework, if necessary. This amendment also removes certain optional terminating actions. This amendment is prompted by reports of cracking of the lower and upper leg of the horizontal clevis of the midspar fitting. The actions specified in this AD are intended to detect and correct cracking and fracturing of the clevis, which could result in drooping of the strut at the strut-to-wing interface, and consequent separation of the engine and strut from the airplane.
AD 97-13-01 · published Jun 20, 1997, effective Jul 25, 1997
Saab Model SAAB 340B and Model SAAB 2000 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 340B and Model SAAB 2000 series airplanes, that requires a one-time inspection to determine if certain switches are installed on the fire handle of the fire handle assembly; and replacement of the fire handle panel with a new fire handle panel, if necessary. This amendment is prompted by a report indicating that, during manufacture, a batch of defective switches were installed on certain fire handle panels on these airplanes. The actions specified by this AD are intended to ensure the proper switches are installed in the fire handle assembly. A defective switch in the fire handle assembly could prematurely fail and, consequently, prevent the proper operation of the engine fire protection system in the event of a fire.
AD 97-13-03 · published Jun 20, 1997, effective Jul 25, 1997
Gulfstream American (Frakes Aviation) Model G-73 (Mallard) Series Airplanes Modified in Accordance With Supplemental Type Certificate (STC) SA2323WE
This amendment adopts a new airworthiness directive (AD), applicable to certain Gulfstream American (Frakes Aviation) Model G-73 (Mallard) series airplanes, that requires revising the Airplane Flight Manual (AFM) to prohibit positioning the power levers below the flight idle stop, and to provide a statement of consequences of positioning the power levers below the flight idle stop. This amendment is prompted by incidents and accidents involving airplanes equipped with turboprop engines in which the propeller beta was used improperly during flight. The actions specified by this AD are intended to prevent loss of airplane controllability, or engine overspeed and consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.
AD 97-13-06 · published Jun 20, 1997, effective Jul 7, 1997
Saab Model SAAB 340B and SAAB 2000 Series Airplanes
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Saab Model SAAB 340B and SAAB 2000 series airplanes. This action requires an inspection of the fluorescent lamps in the cabin area to ensure correct installation, and correction, if necessary. This AD also requires an inspection of the lampholders to identify any discrepancies and to ensure the security of the back covers, and replacement of discrepant lampholders with new lampholders; installation of retaining clips on certain Page Aerospace lampholders; and reinspection of the lamps to ensure correct installation after replacement or reinstallation of the lamps or lampholders, and corrections, if necessary. This amendment is prompted by reports indicating that loose back covers on the lampholders and incorrect lamp installations have led to electrical arcing between fluorescent tube pins and lampholders and consequent charring or melting of the affected areas. The actions specified in this AD are intended to prevent such electrical arcing, which could burn the surrounding area and lead to smoke and fumes in the passenger compartment or lavatory area.
AD 97-13-04 · published Jun 25, 1997, effective Jul 30, 1997
Airbus Model A300-B2 and -B4 Series Airplanes, Excluding Model A300-600 Series Airplanes, Equipped With General Electric CF6-50 Series Engines or Pratt & Whitney JT9D-59A Engines
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300-B2 and -B4 series airplanes, that currently requires an inspection to detect discrepancies of a certain thrust reverser control lever spring; an operational test to verify the integrity of the flight inhibition circuit of the thrust reverser system; and either the correction of discrepancies or deactivation of the associated thrust reverser. That AD also provides for an optional terminating action. That AD was prompted by a report that, due to broken and deformed thrust reverser control lever springs, an uncommanded movement of the thrust reverser lever to the unlock position and a ``reverser unlock'' amber warning occurred on one airplane. The actions specified by that AD are intended to detect such broken or deformed control lever springs before they lead to uncommanded deployment of a thrust reverser and consequent reduced controllability of the airplane. This amendment requires installation of the previously optional terminating action in accordance with the latest service information.
AD 97-13-08 · published Jun 25, 1997, effective Jul 30, 1997
de Havilland Model DHC-8-100 and -300 Series Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to all de Havilland Model DHC-8-100 and -300 series airplanes, that currently requires an inspection to detect discrepancies and damage of the low fuel pressure switch adapter/ snubber (located on each engine fuel heater), and replacement, if necessary. That AD also requires an inspection to detect gaps or openings in each nacelle and engine-mounted firewall area, and in certain weather seals in the nacelles; and correction of discrepancies. This amendment requires certain new modifications to the nacelles that will minimize the passage of flammable fluid through the zones of the nacelle of each engine. The actions specified by this AD are intended to prevent the spread of fire through these zones in the event of an explosion during flight, and consequent structural damage to the airplane.
AD 97-13-05 · published Jun 27, 1997, effective Aug 1, 1997
Fokker Model F28 Mark 0100 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F28 Mark 0100 series airplanes, that requires loosening certain nuts on the horizontal stabilizer control unit (HSCU) to reduce stress on bolts; a one-time inspection of certain bolts on the HSCU to detect cracking, and replacement, if necessary; application of corrosion protection to these bolts; and reassembly and reidentification of the modified HSCU. This amendment is prompted by reports indicating that stress corrosion, resulting from overtightening of nuts on these bolts, has caused some of these bolts to crack and fail. The actions specified by this AD are intended to prevent failure of these bolts because of stress corrosion cracking which, if not corrected, could lead to loss of control of the horizontal stabilizer and reduced controllability of the airplane.
AD 97-14-03 · published Jun 27, 1997, effective Aug 1, 1997
Boeing Model 737-100, -200, -300, -400, and -500 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to all Boeing Model 737-100, -200, -300, -400, and -500 series airplanes, that requires installation of a newly designed rudder-limiting device and yaw damper system. This amendment is prompted by a report indicating that a full rudder input, either commanded or uncommanded, could result in a rapid roll upset; and by reports of malfunctions of the yaw damper system. The actions specified by this AD are intended to prevent excessive rudder authority and consequent reduced controllability of the airplane; and malfunctions of the yaw damper system, which could result in sudden uncommanded yawing of the airplane and consequent injury to passengers and crewmembers.
AD 97-14-02 · published Jun 30, 1997, effective Aug 4, 1997
Airbus Industrie Model A300-600 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Industrie Model A300-600 series airplanes, that requires repetitive eddy current inspections to detect cracks of the outer skin of the fuselage at certain frames, and repair or reinforcement of the structure at the frames, if necessary. This amendment also requires eventual reinforcement of the structure at certain frames, which, when accomplished, terminates the repetitive inspections. This amendment is prompted by a report indicating that fatigue cracks were found in the area of certain frames. The actions specified by this AD are intended to prevent such fatigue cracking, which could reduce the structural integrity of the airframe and result in rapid decompression of the airplane.
AD 97-14-04 · published Jun 30, 1997, effective Aug 4, 1997
Boeing Model 737-100, -200, -300, -400, and -500 Series Airplanes
This amendment supersedes two existing airworthiness directives (AD), applicable to certain Boeing Model 737 series airplanes, that currently require tests of the main rudder power control unit (PCU) to detect excessive internal leakage of hydraulic fluid, stalling, or reversal, and to verify proper operation of the PCU; and replacement of the PCU with a unit having a different part number, if necessary. This amendment adds requirements for replacement of the PCU and the vernier control rod bolts with newly designed units. This amendment also adds a requirement for leak tests of the PCU, and replacement of the PCU with a serviceable or newly designed unit, if necessary. This amendment is prompted by reports of fracturing of the vernier control rod bolts as a result of the shank of the bolt running into the threads on the nutplate during installation of the rod. The actions specified by this AD are intended to prevent such fracturing, which could result in uncommanded movements of the rudder, and consequent reduced controllability of the airplane.
AD 97-13-09 · published Jun 25, 1997, effective Jul 10, 1997
McDonnell Douglas Helicopter Systems Model MD-900 Helicopters
This amendment adopts a new airworthiness directive (AD) that is applicable to McDonnell Douglas Helicopter Systems (MDHS) Model MD- 900 helicopters. This action requires applying specified serial numbers to the left and right vertical stabilizer control system (VSCS) bellcrank assemblies, the forward and aft deck-fitting assemblies, and the mid-forward and mid-aft truss strut assemblies; and establishes new life limits for the non-rotating swashplate assembly, the collective drive link assembly, and the self-aligning, spherical/slider main rotor bearing. This amendment is prompted by additional manufacturer's analysis which indicates a need for the reduction of the life limit on several parts and the addition of non-serialized parts to the life- limited parts list. The actions specified in this AD are intended to establish a life limit for various parts and reduce the current life limit on other parts.
AD 97-12-04 · published Jun 12, 1997, effective Jun 27, 1997
General Electric Company GE90 Series Turbofan Engines
This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company (GE) GE90 series turbofan engines. This action requires initial and repetitive borescope inspections of compressor discharge pressure (CDP) manifolds for cracks, and replacement, if necessary, with an improved design CDP manifold. In addition, this AD requires, as terminating action to the inspections, replacement with an improved design CDP manifold. This amendment is prompted by reports of CDP manifold cracking that has resulted in liberated material causing high pressure compressor (HPC) blade damage. The actions specified in this AD are intended to prevent inflight engine power loss or shutdown due to HPC blade damage caused by liberated material from the CDP manifold.
AD 97-12-05 · published Jun 12, 1997, effective Jun 27, 1997
General Electric Company GE90 Series Turbofan Engines
This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company (GE) GE90 series turbofan engines. This action supersedes Telegraphic AD T97-09-51 that currently requires visual checks of the engine Debris Monitoring System (DMS) sensor for bearing debris, and, if necessary, performing procedures for additional maintenance actions. In addition, that AD requires replacing Variable Speed Constant Frequency (VSCF) gearshaft flange ball bearings that may incorporate rivets that are manufactured of improper material with serviceable bearings. This action references a later revision of the applicable Service Bulletin (SB) that includes additional engine serial numbers; however, these changes do not affect the Applicability or compliance requirements of this AD. This amendment is prompted by the issuance of the new revision to the SB. The actions specified by this AD are intended to prevent a VSCF gearshaft flange ball bearing failure, which could result in an inflight engine shutdown.
AD 97-13-10 · published Jun 27, 1997, effective Aug 26, 1997
General Electric Aircraft Engines CF700 Series Turbofan Engines
This amendment adopts a new airworthiness directive (AD), applicable to General Electric Aircraft Engines CF700 series turbofan engines, that requires replacement of existing fan guards with new, improved fan guards. This amendment is prompted by a report of uncontained fan blades which separated from the engine during an overspeed. The actions specified by this AD are intended to prevent an overspeed of the aft fan disk from resulting in an uncontained engine failure and damage to the aircraft.
AD 97-13-07 · published Jun 27, 1997, effective Jul 14, 1997
Hamilton Standard 54H60 Series Propellers
This amendment adopts a new airworthiness directive (AD) that is applicable to Hamilton Standard 54H60 series propellers. This action requires removing from service affected propeller blades, and returning those blades to the manufacturer or an approved facility for inspection, rework, and return to service. This amendment is prompted by reports of a propeller blade manufacturing defect. The actions specified in this AD are intended to prevent propeller blade fracture due to the manufacturing defect, which could result in propeller blade separation and loss of control of the aircraft.
