Air Safety Week: Significant Regulatory Activity

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Significant Regulatory Activity

Note particularly the emergency airworthiness directive of Aug. 29 and the request for comment on the security initiative of

Sept. 21.

Flight control safety: Emergency airworthiness directive ? Boeing B777- 200, -300 and -300ER

Aug. 29, AD 2005-18-51

Requires installing previous air data inertial reference unit (ADIRU) software pending resolution of a final fix to prevent anomalies in the fly-by- wire primary flight control, which can result in deviation from intended flight path, high pilot workload and possible loss of control of the airplane.

From the Australian Transport Safety Bureau (ATSB) report of investigation, released Sept. 16:

"The pilot in command (PIC) disconnected the autopilot and lowered the nose of the aircraft. The autothrottle commanded an increase in thrust, which the PIC countered by manually moving the thrust levers to the idle position. The aircraft pitched up again and climbed 2,000 ft. The PIC notified air traffic control (ATC) that they could not maintain altitude and requested a descent and radar assistance. The crew was able to verify with ATC the aircraft speed and altitude."

Faulty software caused a Malaysian Airlines B777-200 to pitch up about 32 minutes after takeoff from Perth, Australia, on a flight to Kuala Lumpur on Aug. 1. The pilot in command disconnected the autopilot, but the airplane climbed to 41,000 feet as speed degraded to 158 knots. Both stall warning and stickshaker activated.

Flying the airplane manually, the pilot returned to Perth for a landing. For details see the ATSB report) at www.atsb.gov.au/aviation/occurs/occurs_detail.cfm?ID=767.

The ADIRU failure caused the minimum maneuver and overspeed margins on the speed tape to converge; the indicated airspeed was rock steady, but when the minimum speed indication rose up the speed tape, it caused the autothrottle to think the aircraft was flying too slowly ? and constantly tried to increase power. The problem was with the indications, not the actual speeds; it is a case where you cannot always believe what you see.

Minimum equipment lists (MELS) have recently been altered to reflect this situation. Specifically, the SAARU (secondary attitude/air data reference unit) is no longer an "allowable" inoperative discrepancy.

A Boeing message, sent to all B777 operators on Aug. 9, before the FAA action, said, in part: "The flight crew should disconnect the autopilot and manually fly the airplane. Although initial manual control forces may be high, the affects of the ADIRU anomaly on manual control forces are expected to diminish within 10 seconds and should be back to near nominal within 2 minutes. ? Boeing and Honeywell (ADIRU supplier) are supporting the ATSB investigation and are addressing the issues raised by this event with the highest priority."

Action mandated by the Federal Aviation Administration (FAA) basically overrules AD 2005-10-03, which was supposed to correct the ADIRU software deficiencies but in fact made them worse (see ASW, May 30, May 11 entry).

This is arguably the most significant software-related flight control anomaly yet experienced on a fly-by-wire aircraft in revenue service.

Fuel system safety: Final rule ? Airbus A318, A319, A320 and A321

Sept. 21, FR Doc 05-18518; Docket No. FAA-2005-21189; AD 2005-19-14

Requires modification of electrical bonding of all structures and systems inside the center fuel tank to prevent electrical arcing and consequent explosion of the fuel tank. Airworthiness directive (AD) effective Oct. 26.

Relates to fuel system safety reviews ordered by the FAA and actions under SFAR 88 to reduce ignition sources in fuel tanks. This was one of a number of actions expected to come out in the Federal Register (see ASW, July 11).

Cost estimated between $3,100 to $4,500 per airplane. Affects 506 airplanes in U.S. registry.

Fuel system safety: Final rule ? Airbus A320-111 and A320-200

Sept. 21, FR Doc 05-18520; Docket No. FAA-2005-21861; AD 2005-19-16

Requires installation of a bonding strip between each of the two scavenge pumps of the center fuel tank to prevent an ignition source that could ignite flammable vapors and consequent explosion of the fuel tank. AD effective Oct. 26.

Cost about $65 per airplane. Affects 371 airplanes in U.S. registry.

Navigation safety: Final rule ? Boeing models B737-300 through -900

Sept. 21, FR Doc 05-18523; Docket No. FAA-2005-20347; AD 2005-19-19

Requires installing upgraded software to flight management computer (FMC) to prevent map shifts, which could result in a navigation error and a near miss or possible collision with terrain or other aircraft. AD effective Oct. 26.

Prompted by operator reports of FMC map shifts on several B737-400s.

Cost estimated at $80 to $145 per airplane.

Affects 3,482 airplanes in worldwide service, of which 1,312 are in U.S. registry.

Aviation security: Notice of proposed rulemaking (NPRM), Flightdeck Door Monitoring & Crew Discreet Alerting Systems

Sept. 21, FR Doc 05-18806; Docket No. FAA-2005-22449

FAA proposes for passenger-carrying transport airplanes a means to allow the flightcrew to visually monitor the door area outside the flight deck and, for operations requiring flight attendants, to provide the flight attendants with a means to discreetly notify the cockpit crew of passengers manifesting suspicious activity or security breaches in the cabin.

The following two FAA explications are particularly relevant:

* "The FAA believes that current, on board communication crew alert systems could, along with FAA-approved operator-developed procedures, meet this requirement. For example, subtly keying the interphone in a specific manner could be used. The rule would also allow the use of more sophisticated technology, such as hands-free, wireless method as considered by Congress in the Homeland Security Act."

* "It is the FAA's intent to meet the ICAO standard that requires monitoring of the area outside the flightdeck door by permitting the use of a peep hole to view a large area outside the flightdeck door in conjunction with the audio confirmation, for example, from a crewmember who is outside the flightdeck and who can observe that the flightdeck door area is secure."

Comments due Nov. 21.

This initiative is based on four actions:

1. The findings of the Secretary of Transportation's rapid response team of Oct. 1, 2001, regarding aircraft security, issued in the wake of the Sept. 11, 2001, hijackings, calling for a means to monitor the cabin area immediately outside the cockpit and a means for the cabin staff to alert the pilots to suspected or overt threats in the cabin.

2. The Aviation & Transportation Security Act (ATSA) passed by the U.S. Congress Nov. 19, 2001, calling for the FAA administrator to employ "video monitors or other devices" for cockpit crews to survey the area immediately outside of their locked cockpit, and for cabin crews to have a means of alerting aircrews to security breaches.

3. The Homeland Security Act (HSA) of Nov. 25, 2002, which created the Department of Homeland Security, and authorized the use of discreet, hands-free wireless means for cabin staff to communicate security concerns to the flightcrew.

4. Provisions for enhanced aircraft security adopted by the International Civil Aviation Organization (ICAO) of March 15, 2002, which included a locked cockpit door, a means to monitor the cabin area outside the door, and a means for the cabin staff to notify the flight crew of security breaches.

FAA notes that Europe's Joint Aviation Authorities (JAA) are working a similar rule regarding monitoring of the door area outside the cockpit.

The FAA says that its proposed rule does not meet the ICAO standard in at least two respects:

1. It does not meet the deadline of Nov. 1, 2003, for meeting the ICAO requirement, which is somewhat amazing given that the U.S. was the subject of the devastating terrorist attacks of 9/11 that gave rise to the international requirement.

2. The FAA will not require video monitoring or a discrete means of communication for Part 91 (general aviation), or for Part 125 and 135 aircraft (charter aircraft), only for Part 121 regularly scheduled carriers with a seating capacity of more than 60. The FAA plans to excuse cargo planes from the rule, also.

Video monitoring can use CCTV for this purpose, but the FAA argues that it also can be as simple as a peephole to view the area outside the cockpit. The disadvantage of a peephole is that it requires one of the two pilots to leave his seat, whereas the image from video camera monitoring can be displayed on the instrument panel.

Although Congress described a hands-free wireless device for alerting the cockpit crew to a security problem in the cabin, the FAA says in this action that using a code system on the current cabin-cockpit interphone is sufficient. Terrorists can disable the phone, and that is one of the main reasons why equipping each flight attendant with a wireless device was envisioned.

In sum, this proposal is not even close to what the Congress and ICAO called for, although the threat has not gone away.

Operators will have two years from the date of final rule (whenever that is) to comply with the mandate.

The FAA estimates that the cost of installing and maintaining a video camera surveillance system will be about $185 million. The cost of a flightcrew alerting system is gauged as minimal, given that the existing interphone system can be used for this purpose. The FAA estimates that saving a single flight from hijacking, destruction and death is worth $375 million in direct costs, and therefore the proposed rule meets the test of a cost-benefit calculation. It should be noted that a few years ago, and prior to 9/11, the FAA estimated the cost of a single airliner lost to terrorist bombing at $272 million, indicating that there is no consistency in estimating the cost of a terrorist attack on aviation (see ASW, Aug. 6, 2001).

Fire extinguisher safety: Final rule ? Short Brothers model SDS-30 and SDS-60

Sept. 21, FR Doc 05-18524; Docket No. FAA-2005-21344; AD 2005-19-18

Requires replacement of nozzles and triggers on portable fire extinguishers and modification of the point adapter of the forward and aft cargo bay to prevent fire extinguisher blowback, which could injure the person using the extinguisher. AD effective Oct. 26.

Action prompted by reports of individuals experiencing fire extinguisher blowback when discharged through the point adaptors.

Cost between $1,300 and $1,700 per airplane. Affects 75 airplanes in U.S. registry.

Flight control safety: NPRM ? Boeing B757

Sept. 21, FR Doc 05-18795; Docket No. FAA-2005-22471

Requires measurements and lubrication to reduce or eliminate freeplay- induced vibration of the rudder, which could result in divergent flutter and loss of control of the airplane. Comments due Nov. 7.

Prompted by a report of freeplay-induced vibration of the rudder.

Cost about $260 per measurement cycle and $520 per lubrication cycle. Affects 1,040 airplanes in the worldwide fleet, of which 679 are in U.S. registry.

Safety of escape slides: NPRM ? Boeing B767-200 and -300

Sept. 21, FR Doc 05-18796; Docket No. FAA-2005-22488

Modifies existing AD by removing aircraft not subject to the unsafe condition and requiring action to ensure safe deployment of off-wing escape slide during an evacuation, and to prevent unexpected deployment of escape slide during maintenance. Comments due Nov. 7.

Prompted by reports of worn or damaged door latches and disconnect housing in the off-wing escape slide compartments.

Cost of added inspections estimated at $195 per airplane, per inspection cycle. Affects 694 airplanes in worldwide service, of which 315 are in U.S. registry.

Flight control system safety: NPRM ? Bombardier Series 100 and 440 regional jets.

Sept. 21, FR Doc 05-18794; Docket No. FAA-2005-22481

Requires installation of new components and changes to airplane flight manual (AFM) to prevent an unannunciated failure of the flap system and consequent reduced controllability of the airplane. Comments due Oct. 21.

Action constitutes final action indicated was forthcoming an earler AD.

Cost of new air data computer and skew detection system estimated at $10,700 per airplane. Affects 651 airplanes in U.S. registry.

Flight control safety: Supplemental notice of proposed rulemaking, reopening of comment period ? Embraer EMB-135 and -145

Sept. 21, FR Doc 05-18793; Docket No. 2002-NM-89-AD

Requires installation of a new spring cartridge and other actions to assure functioning of the elevator. Comments due Oct. 11.

Comment period reopened because actions specified expand on scope of original rule.

Cost of applying one service bulletin (SB) to 108 airplanes placed at $18,200 per airplane; applying another SB to 192 airplanes estimated at $31,800 per airplane. Affects about 300 airplanes in U.S. registry.

Structural and hydraulic system safety: Final rule ? Airbus A330-322, - 341 and -342, and A340-200 and -300

Sept. 22, FR Doc 05-18781; Docket No. FAA-2005-22486; AD 2005-19-22

Requires replacing the left and right ram air outlets of the two air conditioning packs with one of improved design to prevent fatigue cracks, which could lead to hot air damage and consequent loss of the hydraulics systems. AD effective Oct. 7.

An interesting example of how one system affects another.

Cost of modification runs to $57,700 per airplane. No airplanes in U.S. registry, but if one were to be imported, it will need this work.

Structural safety: Final rule, request for comments ? Airbus A330-202, - 223, -243 and -343, and A340-313

Sept. 22, FR Doc 05-18782; Docket No. FAA-2005-22484; AD 2005-19-21

Requires one-time inspection and corrective action as necessary to ensure that attachment bolts for the windshield are long enough to engage fully in the self-locking nut, to prevent loss of the windshield. AD effective Oct. 7. Comments due Nov. 21.

Apparent manufacturing defect. Airbus service bulletin requires detailed visual inspection.

Cost estimated at $65 per airplane. No airplanes in U.S. registry, but to import one, the work must be done.

Structural safety: Final rule ? Boeing B727

Sept. 22, FR Doc 05-18783; Docket No. 2002-NM-66-AD; AD 2005-19-24

Requires inspection and repair of support fittings for #1 and #3 engines to prevent separation of engine from the airframe. AD effective Oct. 27.

The cost of operating an old airplane just increased.

Cost for inspections and structural rework estimated at $10,100 per airplane. Action affects 1,009 airplanes in the worldwide fleet, of which 587 are in U.S. registry.

Structural safety: Final rule ? Boeing B767-200, -300 and -300F

Sept. 22, FR Doc 05-18785; Docket No. FAA-2005-21355; AD 2005-19-23

New AD adds inspections at lower tang of midspar fitting and corrective action as necessary to prevent fatigue cracking and separation of the strut and engine. AD effective Oct. 27. Action prompted by discovery of cracks.

Cost of high frequency eddy current (HFEC) inspection, established by this action, is about $260 per airplane. Affects 263 airplanes in U.S. registry.

Flight control safety: NPRM ? McDonnell Douglas DC-10 and MD-11

Sept. 22, FR Doc 05-18907; Docket No. FAA-2005-22503

Requires ultrasonic inspections of the wing flap hinge fittings to prevent their failure and possible separation of the flap from the wing rear spar, and consequent reduced controllability of the airplane. Comments due Nov. 7. Various service bulletins apply.

Cost of ultrasonic inspection estimated at $1,040 per airplane. Affects 594 airplanes worldwide, of which 366 are in U.S. registry.

Structural safety: NPRM ? Boeing B747

Sept. 26, FR Doc 05-19142; Docket No. FAA-2005-22510

Requires detailed inspection and revised compliance times to detect and correct cracking, which could result in reduced structural capability of the horizontal stabilizer, which could lead to loss of control of the airplane. Comments due Nov. 10.

FAA actions on this problem go back to at least 2002 and numerous requirements apply.

Cost of new inspections placed at $2,470 per airplane. Action affects 1,087 aircraft worldwide, of which 227 are in U.S. registry.

Landing gear safety: NPRM ? Gulfstream Aerospace LP Model Gulfstream 100, Astra SPX and 1125 Westwind Astra airplanes.

Sept. 26, FR Doc 05-19141; Docket No. FAA-2005-22511

Requires inspection and corrective action to prevent loss of nose wheel steering and consequent reduced controllability of the airplane on the ground. Comments due Oct. 26.

FAA action emulates an Israeli airworthiness directive.

Cost about $520 per airplane. Action affects 106 airplanes in U.S. registry.

Source: U.S. Federal Register, see www.gpoaccess.gov/fr/index.html