A lower-tech solution to luggage screening, use of sniffer dogs, at least in some circumstances are more effective than some of the highly publicised US air-security measures adopted since the September 11, a security expert has said.

Expressing his concerns about the US practice of placing gun-toting security officers aboard flights, Rodney Wallis, a British aviation expert, told the Air India inquiry commission that 'many aviation security experts will back a good dog over a piece of equipment any day.'

"I don't want to be sitting in an airplane at 35,000 feet while sky marshals are shooting it out with terrorists because the likelihood is they will be my last moments," he said, adding, "There is no place for a weapon of any sort in the cabin of an airplane."

Wallis, who has consulted for International Civil Aviation Organization and other groups, is not the first to warn that gunfights could endanger innocent passengers, who might be hit by stray slugs or, worse yet; die in a crash if a bullet pierces the plane's skin and causes cabin decompression.

Armed Royal Canadian Mounted Police officers ride some Canadian commercial airliners, mostly on routes to Washington, DC, to comply with US requirements.

The inquiry, headed by former Supreme Court justice John Major, is examining the 1985 bombing of Air India Flight 182 by Sikh terrorists based in British Columbia. His mandate is to look at the way terrorist tactics have evolved since then, and to determine whether security reforms have been adequate.

The tragedy led to reforms that include development of automated baggage-handling systems to ensure each suitcase loaded onto a plane is matched with a specific passenger.

Unaccompanied bags are supposed to be pulled off immediately, as the bomb, that brought the plane down was hidden in a suitcase in the baggage hold.

Previous evidence has shown no dogs were on duty at Torontos Pearson airport the week of the Air India bombing because all the RCMP canines were at a training course.