Agencies squabble over air safety
Safety board rates work by Transport Canada 'unsatisfactory'
Larry Pynn
Vancouver Sun
Swissair 111
Two Transportation Safety Board investigators working at CFB Shearwater in September 1998 look over a section of the fuselage recovered off the waters near Peggy's Cove, N.S.

Transport Canada is resisting demands for the wholesale inspection of planes for the same problem that resulted in the deaths of 229 people in a Swissair crash off Peggy's Cove, N.S., seven years ago.

In 2003, Canada's Transportation Safety Board issued a public report attributing the 1998 Swissair Flight 111 crash to worn or faulty entertainment system wiring surrounded by flammable thermal-acoustical insulation blankets. The blankets are hidden from passengers' view, but are used to keep the cabins warm in flight and to minimize noise from aircraft engines.

A year later, in June 2004, the board privately slapped Transport Canada with an "unsatisfactory" rating for its response to a board recommendation that other types of blankets that might cause a similar crash be checked and fixed if necessary, according to federal access-to-information documents obtained by The Vancouver Sun.

(The insulation material that contributed to the fire aboard the Swissair passenger jet was pulled from aircraft effective June 2005.)

The access-to-information documents provide insight into the tension between the two federal agencies -- the safety board, which investigates crashes and makes recommendations, and Transport Canada, which deals with the reality of implementing them.

A seven-page document titled "Reassessment of Risk," dated June 16, 2004, reveals the safety board wants to know what other types of blankets still being used in planes fail the Radiant Panel Test (RPT), a flammability standard adopted by the Federal Aviation Administration in the U.S.

"Although these materials exist in many aircraft, as of the final report publication date, no mitigation strategy has been undertaken to address the known associated risks," states the document.

Transport Canada argued in response that those materials that failed the test are not necessarily unsafe because

 some "did pass a range of other flammability tests and have performed satisfactorily in-service."

The documents also show that Transport Canada has developed proposed regulations to implement the RPT on new transport category aircraft designs and future production of existing aircraft designs.

Transport Canada said it would also raise the issue of further testing of insulation blankets with the FAA's International Aircraft Materials Fire Test Working Group.

Transport Canada does say that despite improvements to aviation safety taking effect this month, there is still the

 risk of another disastrous crash under similar circumstances.

"Yes, there's clearly a level of risk there," Martin Eley, director of aircraft certification for Transport Canada, said in an interview. "To some extent it's not easy to quantify, and that's been part of the challenge."

The access-to-information documents show the safety board was clearly dissatisfied with Transport Canada's response, which did not fully address the issue of untested thermal blankets on aircraft already in use.

The board states: "TC will not specifically target materials that have failed the RPT. TC has not provided information that it would identify the materials that failed the RPT. Nor has TC indicated an intent to determine the extent to which such materials are used in Canadian-registered aircraft. Consequently, TC's response . . . continues to be assessed as being unsatisfactory."

Since the safety board issued its unsatisfactory rating, there has been action on the issue:
  •  The insulation material that contributed to the fire aboard the Swissair passenger jet, metallized polyethylene terephthalate, has been pulled from aircraft effective June 2005.


  • The FAA has served notice it plans to ban a second type of insulation blanket constructed of polyethyleneteraphthalate film -- AN-26 -- on Boeing aircraft after tests showed it can contribute to the spread of fire as a result of electrical arcing or sparking.


  • Effective this month, the FAA requires the airline industry to install only RPT-approved insulation blankets on new aircraft and when replacing blankets on existing aircraft. Canada is the process of adopting matching regulations.

That still leaves a big question regarding the flammability risk posed by numerous other types of insulation blankets already in use on aircraft where there are no immediate plans for their replacement.

In an airworthiness bulletin issued April 4 this year, the FAA noted that "even though we did extensive testing on a variety of materials, we could not identify and test every material produced, as the permutations of material combinations were too extensive."

Vic Gerden, the safety board's lead investigator on the Swissair crash, said he is glad to see progress being made as a result of the safety board's exhaustive investigation into Canada's second worst airline crash.

"In good measure, they are the result of our work," he said, noting work is also under way to improve detection of fires on aircraft and to improve crew response. "I'm gratified. There has been improvement made."

But Gerden cannot say whether other blankets are still out there posing a threat similar to that in the Swissair crash.

"Yes, that's true, that's a fact," he said, noting there are potentially dozens of types of insulation blankets manufactured over the years. "I'm not in a position to make that assessment."

Any change in the unsatisfactory rating issued by Transport Canada will have to await a further review, Gerden said.

Eley said the unsatisfactory rating is "not that common," even though the two agencies may disagree on approaches to solutions.

"Obviously, we don't like to be in that position," he said of the current rating. "On the other hand, if anyone wants to know our position, we can explain why there is a disagreement."

In this case, Transport Canada, which works closely with the FAA, felt the board's recommendation to eliminate potentially flammable insulation blankets "was a very open question, and we were reluctant to commit to it," Eley said. "We've been responding to what we believe is the concern, but we didn't necessarily agree with the wording of the recommendation. We felt there were better ways to deal with it."

Eley noted that economics play a major part in any decision related to the further removal of thermal blankets.

Removal and replacement of AN-26 blankets on 1,613 aircraft would cost the airline industry more than US$330 million, the FAA estimates.

Given the high cost, government and the aviation industry are looking at cheaper, yet effective, alternatives, such as spraying the existing insulation with a coating that would help to protect it against fire.

Eley said the two types of insulation blankets acted upon to date are the ones that have emerged as problems.

"The risk is out there," Eley said. "We can't treat it lightly. But experience has shown it's not a common problem, even though there is a problem there and we are working to address it."

The Swissair crash was the second most serious aviation disaster in Canadian history. The biggest was the crash of an Arrow Air DC-8, which went down after refuelling in Gander, Nfld., killing 256 passengers and crew, mostly U.S. soldiers, in 1985.  from this link

 The Vancouver Sun 2005