Transportation Safety Board of Canada / Bureau de la sécurité des transports du Canada
Menu (access key: M)
Skip first menu (access key: 1)
TSB Reports

Éviter tous les menus (touche d'accès : 2)

Curve Graphic

SR 111 Investigation Report

Heading Graphic

Horizontal Line

4.1.9  Standby Instrumentation Transportation Safety Board of Canada Swissair United States Federal Aviation Administration The Boeing Company

Back to the top  Transportation Safety Board of Canada

The investigation revealed that, as the SR 111 emergency progressed, various systems-related failures occurred that affected primary instrument displays and that standby instruments were being used. Given the substantially increased pilot workload during the emergency, the investigation became interested in the adequacy of the standby instrumentation. The results of TSB's inquiry indicated that when pilots have been forced to rely on standby instruments in emergency situations, they have noted deficiencies, including poor instrument location, small displays, difficulty in transition from primary flight instruments, and lack of adequate training.

It was determined that, while the Swissair MD-11 standby instruments meet regulatory requirements, their functionality may not be optimized. Limitations with respect to location, powering, and pilot training resulted in the TSB issuing two ASAs (A010042-1 (STI4-26) and A010042-2 (STI4-27)) on 28 September 2001. The advisories suggested that authorities consider reviewing the existing requirements for standby instrumentation, including related issues such as standby communication and navigation capabilities. The advisories also called for a review of present regulations and practices to ensure that flight crews receive adequate training in the use of standby flight instruments and that design standards be adequate to ensure that standby instruments are grouped adjacent to one another, and have a layout similar to the primary flight instruments.

Back to the top  Swissair

As part of its "MD-11 Modification Plus" program, Swissair chose to install a secondary flight display system that has a layout similar to the primary flight display in the MD-11 aircraft. The display system includes attitude, airspeed, altitude, and heading in a single integrated display. In addition, in the event of a loss of primary aircraft electrical power to the unit, the display has an auxiliary battery that can supply power for a minimum of 45 minutes.

Back to the top  United States Federal Aviation Administration

The FAA plans to address the emergency instrumentation issues raised by the TSB at the appropriate Aviation Rulemaking Advisory Committee (ARAC). This forum will compare the issues raised by the TSB with current safety issues and will decide upon a course of action.

Back to the top  The Boeing Company

Boeing advises that they have reviewed their current standby instrumentation equipment in an effort to identify any areas that could be optimized. As part of its ongoing product improvement effort to its customers, Boeing offers standby instrument systems, such as their Integrated Standby Instrument System used on the B-717, that combine several standby instrumentation requirements in a single display.

Previous | Next

Horizontal Line
Updated: 2003-03-27

Back to the top

Important Notices