One wonders why pilots are doing performance calculations on laptops and then having to manually input the data coughed up into the FMS. As we have seen on a number of occasions (MEL, AKL, MK and there must be others) the routine is ripe for errors. Yet the technology has been available for years to overcome the problem IMHO (not being a jet driver).
From the Honeywell website (my bolding)- The Honeywell Weight and Balance System measures aircraft gross weight and center of gravity using sensors mounted on the aircraft landing gear. A dual system is capable of being certified as an alternate means of providing dispatch weight and balance information. The system is designed so that any individual component can be changed out without re-weighing the system. The system is standard equipment on the Freighter version of 747-400 aircraft. The system interfaces directly with the Flight Management Computer system on the aircraft and the output is displayed on the Multifunction Control Display Unit (MCDU). An optional Remote Dedicated Display Unit can be utilized in the cargo bay.
FLIGHT INTERNATIONAL 1 July 1989
747 auto-balance system certificated
The US Federal Aviation Administration has certificated an electronic weight and balance measuring system (WBS) on the Boeing 747-400. The Honeywell Air Transport Systems division WBSs were installed ready for operation in the 747-400s recently delivered to KLM and Lufthansa. Certification does not yet clear it as a primary system, but as a means of checking the standard weight and balance calculations.
The system gives real-time readouts of aircraft weight and centre of gravity. KLM selected an optional cargo bay remote display for monitoring by loaders.
Because actual (not estimated) aircraft weight is measured automatically, departure delays caused by late passenger or cargo arrival can be minimised because cockpit paperwork and calculations are eliminated. The system automatically alerts the crew if loading limits are exceeded.
Certification has cleared the WBS to an accuracy of ±1 percent, and the dual system is designed ultimately to be certificated as a primary means of dispatch to FAR Part 121 standards. Lufthansa hopes for European certification of its dual WBS as a primary dispatch system. In the meantime it is useful as a means of checking the accuracy of conventional loadsheets, and particularly for giving an accurate final readout on the CG position.
The Honeywell WBS consists of landing-gear-mounted load sensors, a calibration module containing all gear parameter information, a digital computer unit, a pitch attitude sensor, a cockpit display, and an optional remote dedicated display unit.
A dual system such as Lufthansa's includes two variable reluctance sensors per wheel, or a total of 36 sensors. Air France, China Airlines, and French independent airline UTA have ordered the WBS for their 747-400s, and Alitalia and China Airlines for their McDonnell Douglas MD-l1s.
As I understand it Airbus has such a system available as an option and has been certified on the A300-600, A310, A320, A330, A342 and A343.
What is holding back the fitting of such tools? Short term monetary considerations, forgetting the old maxim "If you think this is expensive try having an accident". Perhaps the industry may have been better served in the long term (and I hate to say it - its the old railway crossing argument) if there had been loss of life. Thats when political pressure is brought to bear, the airlines themselves are rarely proactive on such matters and it requires mandating from some authority before they stir (kicking and screaming).
David Beaty
Firstly, there should be an acknowledgment that if and when the pilot makes a mistake, his will probably be the final enabling one at the apex of a whole pyramid of errors down below. This will, in turn, take the heat off investigations – the ‘we intend to find and punish the culprit’ syndrome. Only then can the pilots come forward and admit to mistakes they made or nearly made, and the reasons why can be coolly analysed and lessons learned.
Stanley Roscoe wrote that:
The tenacious retention of ‘pilot error’ as an accident ‘cause factor’ by governmental agencies, equipment manufacturers and airline management, and even by pilot unions indirectly, is a subtle manifestation of the apparently natural human inclination to narrow the responsibility for tragic events that receive wide public attention. If the responsibility can be isolated to the momentary defection of a single individual, the captain in command, then other members of the aviation community remain untarnished. The unions briefly acknowledge the inescapable conclusion that pilots can make errors and thereby gain a few bargaining points with management for the future.
Everyone else, including other crew members, remains clean. The airline accepts the inevitable financial liability for losses but escapes blame for inadequate training programmes or procedural indoctrination. Equipment manufacturers avoid product liability for faulty design. Regulatory agencies are not criticised for approving an unsafe operation, failing to invoke obviously needed precautionary restrictions, or, worse yet, contributing directly by injudicious control or unsafe clearance authorisations. Only the pilot who made the ‘error’ and his family suffer, and their suffering may be assuaged by a liberal pension in exchange for his quiet early retirement – in the event that he was fortunate enough to survive the accident
Thus far it seems EK has ticked every box in the Beaty and Roscoe statements.
The technology is available, what is lacking is the will.