Canadian investigators believe crew struggled to read standby displays in 1998 crash

Canada's Transportation Safety Board (TSB) wants an industry-wide review of the design of emergency cockpit instruments following suggestions that the pilots of the Swissair Boeing MD-11 operating flight SR111 that crashed off the coast of Nova Scotia in September 1998 may have had trouble reading their back-up instruments minutes before the crash.

TSB investigators say there are indications that standby instruments were used by the crew in the later stages of the flight.

Switching to standby instruments in a crisis may be hampered "by having the instruments positioned away from the normal line of vision and by not having them in a standard grouping layout", the TSB says in a safety advisory. "The result could be disorientation of the flight crew and loss of control."

In addition, when pilots are forced to use standby instruments in an emergency, they encounter problems such as poor location, inadequate size of displays and difficulty in switching from primary instruments.

The TSB says the challenge of using standby instruments is even greater if flight crews are not well trained in their use or have not used them recently. The Swissair crew's problems were exacerbated because they were diverted to an unfamiliar airport (Halifax, Nova Scotia) at night with smoke in the cockpit and oxygen masks on.

The TSB suggests an overall review of instrument placement for all aircraft and the installation of a second independent power source for all communications and navigation systems. It would also allow for more options when "de-powering an aircraft's electrical system in a smoke/fire event".

Source: Flight International