Monday January 11 7

Monday January 11 7:14 PM ET

U.S. Board Urges MD-11 Jet Wiring Checks

By Tim Dobbyn

WASHINGTON (Reuters) - New clues from the wreckage of last September's Swissair crash off the east coast

of Canada have prompted U.S. safety investigators to ask the Federal Aviation Administration to order checks

of cockpit wiring in other MD-11 planes. The National Transportation Safety Board (NTSB) said Monday it was

concerned about electrical wires showing signs of arcing damage, indicating a short circuit, recovered from the

aircraft, and wiring faults found in other Boeing Co. MD-11s.

In a letter dated Jan. 11, the NTSB recommended to the FAA that it require on an ``expedited basis'' the inspection

of all MD-11 planes for problems with the wiring in and around two circuit breaker panels in the cockpit. The FAA

said in a statement it had already started work on proposals to address the wiring concerns raised by the crash.

Swissair Flight 111 plunged into the Atlantic Ocean near the fishing village of Peggy's Cove, Nova Scotia on Sept. 2,

killing all 229 people on board. About 16 minutes before the crash, the flight crew reported smoke in the cockpit

but was unable to make an emergency landing requested for Halifax International Airport.

The three-engined wide-body jet had been on an evening flight from New York bound for Geneva, Switzerland.

Canada's Transportation Safety Board (TSB) is leading the accident investigation but the NTSB is taking part

because a U.S.-made aircraft was involved.

The NTSB said two wires identified as feeding power to the overhead circuit breaker panel had been

found with arcing damage. Other wires with arcing damage came from the entertainment system.

Swissair voluntarily shut off the entertainment system on its other planes back in October when the

first- and business-class perk first came under suspicion for its possible role in the crash.

At a news conference in Canada Monday, TSB chief investigator Vic Gerden displayed two pieces of wiring

recovered from near the overhead circuit breaker panel. Portions of that overhead panel and an adjacent circuit

breaker panel, on the right side of the cockpit controlling power to the flight electronics, were found to have

substantial heat damage.

Post-accident checks of other MD-11 planes found damage to wires above the forward entry doors.

The FAA last December asked airlines to examine those door areas, but the NTSB said the examinations also

found inconsistent routing of wires and unsealed electrical conduits and open smoke barriers between the

cockpit and cabin areas. NTSB Chairman Jim Hall said Boeing and Swissair had developed a voluntary wiring

inspection program for Swissair's remaining MD-11 planes and no serious problems had been found.

Hall also said that although the electrical arcing had not been determined to be the source of a fire, he was

troubled by the latest discoveries.

``The Safety Board is concerned about the recent discoveries of apparent electrical arcing damage to wiring near

the accident airplane's overhead and avionic circuit breaker panels,'' said part of the NTSB letter to the FAA.

One of the wire samples displayed by Gerden was of Kapton polyimide insulated wire, which some critics have

noted has been banned from stressful military environments because it can sometimes destruct spectacularly in a

condition known as arc tracking. Another piece of wire displayed by Gerden was insulated by a plastic known

as tefzel or ETFE.

Patrick Price, a former wire expert at Boeing, told Reuters that tefzel produces copious smoke when it catches

fire and in tests had also been shown to burn explosively in some situations.

``Some of this wiring that we've recovered ... does show signs of arcing,'' Gerden said at the Canadian Forces Base

Shearwater near Halifax, noting that the breakdown of wire insulation material during arcing can ``create

substantial heat.''

Jan 11 1999

7:59PM EST

American advisors on your team were informed of these various anomalies as soon as they

became known and there have already been prompt actions taken within the United States to

address some of the issues. The Federal Aviation Administration (FAA) has released

Airworthiness Directive (AD 98-25-11) requiring a one-time inspection above the 1L and 1R

doors to address the wire chafing issue brought to light during this investigation. The Boeing

Aircraft Company - Long Beach Division have created two MD-11 Alert Service Bulletins (ASB),

MD-24A068 Revision 1 and MD-25A194 Revision 4, which address the specific discrepancies

noted over the 1L and 1R door areas. These prompt actions by the FAA and Boeing were

prudent, and the results of the inspections should improve the Swissair 111 team's understanding

of the nature and scope of any wiring safety deficiencies.

The TSB investigation team has not established a direct relationship between the wiring

discrepancies discovered in the in-service MD-11s that were recently inspected and the damaged

wire from the Swissair 111 wreckage. However, given the fact that several instances of wire

discrepancies were discovered at two separate MD-11 maintenance facilities, questions arise about

how widespread these phenomena might be within the MD-11 fleet. In conjunction with the Boeing

Company, SR Technics, on behalf of Swissair, has voluntarily developed and completed an

Engineering Order which defines a comprehensive examination of the wiring in the forward areas

of the Swissair MD-11 aircraft. The TSB commends this pro-active effort.

Although the full scope of any wiring safety deficiencies and the risks posed to the MD-11 fleet

worldwide are not known, it may nonetheless be timely for the NTSB and the United States

regulatory authority to take stock of these various preliminary findings and the specific safety

actions taken. Following this review, you may decide that the situation warrants a more

comprehensive look at the state of the wiring in the existing MD-11 fleet, and perhaps other

aircraft fleets.

The TSB investigation team led by Mr. Gerden will, of course, continue to work closely with your

representative and advisors and your Swiss counterparts; I would appreciate hearing of any

actions planned as a result of this Safety Advisory.

Yours sincerely,

J.L. Maxwell

Director, Investigations (Air)

c.c. Mr. John Overney - Accredited Representative for Switzerland

Aircraft Accidents Investigation Bureau

Bahnholfplatz 10 B

CH -3003 Berne, Switzerland

Mr. J. C. Montplaisir

Transport Canada Minister's Observer

Heritage Court, 95 Foundry St.

P.O. Box 42, Moncton, NB E1C 8K6

Mr. Bob Henley - Air Safety Investigator - FAA

FAA Headquarters

800 Independence Ave., S.W.

Washington, DC 20591

MD-11 Wiring Inspections Urged Concerns About Electrical Arcing Voiced to FAA

By Glem Johnson
The Associated Press
W A S H I N G T O N, Jan. 11 — The National Transportation Safety Board today recommended that airlines

perform expedited inspections of their MD-11 aircraft for signs of electrical trouble like that found in the wreckage

of Swissair Flight 111. In a letter to the Federal Aviation Administration, the board said it was concerned by signs

of heat damage and electrical arcing found by Canadian investigators in an overhead cockpit panel and the avionics

circuit bay of the doomed plane.

"Although the apparent electrical arcing on Swissair Flight 111 has not been determined to be a source of fire, and

Swissair's voluntary inspections of its MD-11 airplanes have not uncovered any serious discrepancies, the safety

board is concerned about the recent discoveries," NTSB Chairman Jim Hall wrote to FAA Administrator Jane

Garvey. The board said the FAA should require an inspection of all MD-11s for wiring discrepancies around the

cockpit overhead circuit panel and the avionics circuit breaker panel. It said the inspection should include

examinations for loose wiring, inconsistent wire routings, broken bonding wires and chafed and cracked wire

insulation.

FAA Already Considering Moves FAA spokeswoman Diane Spitaliere said: "Even before we received the ...

(recommendation), the FAA had started to develop rulemaking actions that address the wiring concerns raised by

the Swissair accident. These proposed actions are on a fast track and we expect to issue them shortly." The FAA

has already ordered more limited inspections and repairs around the plane's forward passenger doors and to an

electrical switch in the cockpit.

There are 186 MD-11s in the worldwide fleet, roughly 65 of which are flown by U.S. airlines. While FAA orders

do not apply to foreign-registered aircraft, aviation authorities typically follow each other's safety recommendations.

The Swissair plane, bound from New York to Geneva, plunged into the ocean off Nova Scotia on Sept. 2. The

crash occurred 16 minutes after the pilots reported smoke in the cockpit. All 229 aboard were killed.

(BARRY, FYI:)

Focus Shifts to Cockpit Damage

Investigators still have not determined the cause of the crash, but they are focusing on signs of heat and fire damage in the
cockpit. In December, the FAA ordered a one-time inspection of MD-11s to detect problems such as nicks, fraying or chafing above the left and right front passenger doors. Any problems had to be repaired. Investigators learned that when the doors were raised to the open position, sliding panels above them moved inward and could chafe the electrical wiring in those areas. That could lead to an electrical fire in the passenger cabin.

In November, the FAA ordered airlines to inspect lighting dimmer switches in the MD-11 cockpit. The agency was concerned the switches might overheat and smoke, distracting the pilots. Swissair also agreed in October to discontinue use of an advanced in-flight entertainment system on its MD-11s and some Boeing 747s as a safeguard against electrical problems. Swissair acted voluntarily after investigators from the Transportation Safety Board of Canada detected signs of heat damage on wiring and other debris from the ceiling around the cockpit.

S U M M A R Y

The National Transportation Safety Board is asking the FAA to order inspections of wiring in
MD-11s, the same craft as Swissair Flight 111.

More on MD-11s FAA Orders MD-11 Inspections

The NTSB said the inspection should include examinations for loose wiring, inconsistent wire routings, broken bonding wires and chafed and cracked wire insulation.

FAA Orders MD-11 Inspections
Frayed Door Wiring

The Associated Press
W A S H I N G T O N, Dec. 9 — Concern about frayed wiring on the front passenger doors on MD-11 aircraft prompted the Federal Aviation Administration today to order inspections of the wires.

The agency said it had no evidence that the wires were related to the Sept. 2 crash of Swissair Flight 111, an MD-11, but that signs of wear were detected during recent heavy maintenance performed on another MD-11.

The airworthiness directive requires a one-time inspection within 10 days to detect problems such as nicks, fraying or chafing above the left and right front passenger doors. Any problems must be repaired before further flight, and all inspection results must be reported to the FAA within 10 days of the examination. Investigators learned that when the doors are raised to the open position, sliding panels above them move inward and can chafe the electrical wiring in those areas. The condition, if not fixed, could lead to an electrical fire in the passenger cabin.

Cause of Swissair Crash?
The Swissair plane plunged into the ocean off Nova Scotia 16 minutes after the pilots reported smoke in the cockpit. All 229 aboard were killed. Investigators still have not determined the cause of the crash, but they are focusing on signs of heat and fire damage in the cockpit. Aviation Week & Space Technology reported this week that small pieces of wreckage from the area in front of and behind the cockpit-cabin bulkhead show signs of fire damage, perhaps indicating a fire in the roof. Today's order applies to 65 U.S.-registered MD-11s. Worldwide, there are 174 such aircraft. The cost of the repairs is estimated at $120 per airplane. Swissair has already agreed to discontinue use of an advanced in-flight entertainment system on its MD-11s and some Boeing 747s as a safeguard against electrical problems. The FAA also recently ordered airlines to inspect lighting dimmer switches in the MD-11 cockpit.