Safety Rules and Regs

Emergency Airworthiness Directive (EAD). MD Helicopters MD-500 and 600N. There have been two incidents of impaired directional control. This impaired directional control occurred after the Vertical Stabilizer Control System (VSCS) circuit breakers were pulled in accordance with EAD 2008-18-51. EAD 2008-18-51 was issued on August 20, 2008 and requires several actions related to the VSCS for the MDHI MD900 helicopter and related to the Yaw Stability Augmentation System (YSAS) for the Model 500N and 600N helicopters. EAD 2008-18-51 was prompted by reports that two MD900 helicopters experienced broken VSCS adapter tubes. In one case, the helicopter experienced an uncommanded yaw, resulting in loss of a window and a door. The same part-numbered adapter tube is part of the Model 500N and 600N helicopter's YSAS. Some of the VSCS and YSAS adapter tubes were not manufactured to the required specifications and can fail. Since the issuance of EAD 2008-18-51, we have discovered that pulling the circuit breaker is causing impaired directional control, which could result in loss of control of the helicopter. Therefore, this EAD supersedes 2008-18-51 and requires turning OFF the VSCS or the YSAS instead of pulling the circuit breakers and installing placards that limit airspeed to 100 KTS or VNE, whichever is less. For the Model MD900 helicopters, limiting flight to VFR, prohibiting use of the autopilot, and making changes to the Emergency Procedures and Airworthiness Limitations sections of the RFM are also required. For all of the helicopter models, replacing the adapter tubes with airworthy adapter tubes that have a date stamp is also required. The adapter tubes must be replaced within 45 days and is terminating action for the requirements of this EAD.

Airworthiness Directive; Boeing Model 737-100, -200, -200C, -300, -400, and -500 Final Rule. SUMMARY: This AD requires repetitive inspections to detect cracking of the body station 303.9 frame, and corrective action if necessary. This AD also provides for optional terminating action for the repetitive inspections. This AD results from reports of cracks found at the cutout in the web of body station frame 303.9 inboard of stringer 16L. We are issuing this AD to detect and correct such cracking, which could prevent the left forward entry door from sealing correctly, and could cause in-flight decompression of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Final Rule. SUMMARY: 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: Resulting from the assessment of fuel tank wiring installations required by SFAR 88 (Special Federal Aviation Regulation 88) and equivalent JAA/EASA (Joint Aviation Authorities/European Aviation Safety Agency) policy, BAE Systems identified features in the Jetstream 4100 where the need for design changes was apparent. Internal fuel tank wiring chafing damage, if not corrected, could lead to ignition of fuel vapors and subsequent fuel tank explosion.

Airworthiness Directive; DG Flugzeugbau GmbH Model DG-500MB Powered Sailplanes. Final Rule. SUMMARY: 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: A DG- 500MB experienced, after the engine shutdown, an uncommanded retraction of its powerplant. Investigations revealed that some bolts of the extension retraction mechanism had fractured because of fatigue stress due to increasing push-pull loads acting on incorrectly tightened screws. This condition, if not corrected, could lead to damage of the propeller and the fuselage, thereby reducing the structural integrity of the sailplane.

Airworthiness Directive; Boeing Model 707 Airplanes, and Model 720 and 720B Final Rule. SUMMARY: This AD requires repetitive detailed inspections to detect cracks and corrosion on any existing repairs and at certain body stations of the visible surfaces of the wing to body terminal fittings including the web, flanges, and ribs; and applicable related investigative and corrective actions. This AD results from reports of cracks found in the wing to body terminal fittings during routine inspections. We are issuing this AD to prevent cracks and corrosion in the body terminal fittings, which could cause loss of support for the wing and could adversely affect the structural integrity of the airplane.

Airworthiness Directive; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model ERJ 170 & Model ERJ 190. Final Rule. SUMMARY: 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: It has been found that some ''caution'' messages issued by the Flight Guidance Control System (FGCS) are not displayed on aircraft equipped with [certain] EPIC software load[s]. Therefore, following a possible failure on one FGCS channel during a given flight, such a failure condition will remain undetected. If another failure occurs on the second FGCS channel, the result may be a hardover command by the autopilot. An unexpected hardover command may cause a sudden roll, pitch, or yaw movement, which could result in reduced controllability of the airplane. We are issuing this AD to require actions to correct the unsafe condition on these products.

Airworthiness Directive; Airbus Model A318, A319, A320, and A321 Equipped With Certain Northrop Grumman (Formerly Litton) Air Data Inertial Reference Units. Final Rule. SUMMARY: The FAA is superseding an existing airworthiness directive (AD), which applies to certain Airbus Model A319, A320, and A321 series airplanes equipped with certain Litton air data inertial reference units (ADIRUs). That AD currently requires modifying the shelf (floor panel) above ADIRU 3, modifying the polycarbonate guard that covers the ADIRUs for certain airplanes, and modifying the ladder located in the avionics compartment for certain airplanes. This new AD requires those modifications on additional airplanes. This new AD also requires replacing all three ADIRUs with improved ADIRUs. This new AD also adds Model A318 series airplanes to the applicability. This AD results from reports that ''NAV IR FAULT'' messages have occurred during takeoff due to failure of an ADIRU and subsequent analysis showing that the shelf modification has not sufficiently addressed failure of an ADIRU. We are issuing this AD to prevent failure of an ADIRU during flight, which could result in loss of one source of critical attitude and airspeed data and reduce the ability of the flight crew to control the airplane.

Airworthiness Directive; Boeing Model 727. Final Rule. SUMMARY: The FAA is superseding an existing airworthiness directive (AD), which applies to certain Boeing Model 727 series airplanes. That AD currently requires repetitive inspections to detect cracks and loose brackets of the elevator rear spar, and corrective actions if necessary. The existing AD also provides for an optional terminating action for the repetitive inspections. This new AD reduces the repetitive intervals of the inspections, mandates the previously optional terminating action for the repetitive inspections, and no longer allows stop-drilling. This AD results from new reports of cracks, elongated fastener holes, and loose fittings of the elevator rear spar. We are issuing this AD to prevent cracking of the elevator rear spar at the tab hinge locations, which could cause excessive freeplay of the elevator control tab and possible tab flutter, and consequent loss of control of the airplane.

Airworthiness Directive; Boeing Model 737-600, -700, -800, and -900. Final Rule. SUMMARY: This AD requires installing hot short protector (HSP) support brackets and equipment for the fuel quantity indicating system (FQIS) fuel densitometer and other specified actions as applicable. This AD also requires revising the Airworthiness Limitations (AWLs) section of the Instructions for Continued Airworthiness to incorporate AWL No. 28-AWL- 07. This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent the center tank fuel densitometer from overheating and becoming a potential ignition source inside the center fuel tank, which, in combination with flammable fuel vapors, could result in a center fuel tank explosion and consequent loss of the airplane.

Airworthiness Directive; McDonnell Douglas Model DC-10-10 and DC-10-10F,DC-10-15, DC-10-30 and DC-10-30F (KC-10A and KDC-10), DC-10-40 and DC-10-40F, Model MD-10-10F and MD- 10-30F, and MD-11 and MD-11F. Final Rule. SUMMARY: This AD requires modifying the fuel boost pumps. This AD results from a fuel boost pump found with blown thermal fuses and a fractured thrust washer. We are issuing this AD to prevent failure of the fuel boost pumps, which could lead to the potential of ignition sources inside fuel tanks. This condition, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

Airworthiness Directive; Boeing Model 747 Airplanes. Final Rule. SUMMARY: This AD requires a one-time inspection of certain fuselage skins at section 41 to find any external doublers that cover the inspection areas and to identify the external doublers that end on a stringer and those that do not, and related investigative and corrective actions if necessary. This AD results from reports of cracks found at fastener locations in the fuselage skins at section 41. We are issuing this AD to detect and correct fuselage skin cracks at fastener locations along the skin-to- stringer attachments, which could join together and become large and consequently result in rapid decompression of the cabin.