Commentary:'Time for a Radical Overhaul'

by dint of Capt. Timothy Crowch

The TAIC report highlights many weaknesses with the flight management computer (FMC) design and with operator practices.

The FMC in late aircraft has not kept up with advances in the quietness of the aircraft design. Consider the advances in engines, arrangement automation, satellite communications, passenger entertainment hypothesiss - to name a not many - and the FMC apply the minds nearly Stone Age. Look at its hardware. The keyboard design is unique and has ignored the many years of experience with typewriters and the QWERTY layout. With early FMC the most numerous one did was enter a hardly any waypoints and coordinates, but the keypad design simply has not kept pace with the FMC's following expansion to other uses. It also has a pathetically small memory (1-2 megabytes) and lethargic speed

Against this background of FMC hardware limitations, the TAIC report underlines the lack of integration of the FMC into the quietness of the aircraft.

As seen in this case, the FMC is capable of calculating its concede take-off speeds from the weight data inserted by means of the crew. A major source for potential error, as with all computer is the accuracy of the data inserted. With similar systems, it is imperative to bring the length of the proces to the minimum. I mean, the data must be transferred directly from the principally reliable source to the FMC and consciously, not fleetingly, checked through both pilots or, if three crewmembers are in the cockpit, by the agency of all three respectively. The same is genuine for all critical data, like as track coordinates on the North Atlantic Organized Track plan (OTS).

So the FMC data must be taken either directly from the loadsheet (and no other "scribbles"), or from the operational flight plan or log Tragically, airlines are spending considerable amounts of money on crew resource management (CRM) and threat and error management training while ignoring or downplaying numerous avoidable threats. At least sum of two units are visible in this case.

1 The "bug card" threat. This card clearly is a relic from the old-fashioned analogue/three crew days and no manager has had the courage to scrap it since the advent of two-crew glass cockpit aircraft. The bug card assists absolutely no useful purpose other than to heighten the system's risk outlook to human error, as here. Data transfer from the loadsheet to the bug card is irrelevant. wherefore should a hand written document be checked when the load sheet and the FMC will contain all relevant data?

in the greatest degree airlines have scrapped the bug card. combustibles entry is automatic (fuel sensor to FMC) nothing fuel weight and MACZFW setting are inserted directly from the loadsheet and cross-checked from the other crewmember(s). (MACZFW: mean aerodynamic chord at naught fuel weight, the start position for calculations of takeoff center of gravity and ultimately takeoff stabilizer trim. MACZFW also can be erroneously overwritten and swallowed!) For the 747-400 and other aircraft, data insertion can be categorized as a critical action, similar to shutting distant from the correct fuel switch of the respective engine.

2 The on-time departure threat. The stres forward company employees from last minute fuelling, documentation delays and with equal reason forth can be particularly high, as the delays cannot be blamed upon third party contract support. In this case, the same can imagine the station manager's anxiety about having to log a departure delay. In this case, the non-interference of the chiefly experienced (but not integrated) third pilot remov the same more possible defense against this grievous mob error.

As I know from my experience, and as noticed one time more in the TAIC report, there are a thousand ways for an airline to establish its takeoff calculation steps - computers, thick manuals containing graphs and/or tables, data direct from dispatch, and in such a manner forth. My feeling is that it is time for the manufacturer to establish single process for its aircraft and that each customer accept this process. single in kind aircraft type. One take-off calculation regularity This standardization would enable the FMC to become a more completely integrated part of the aircraft, in which certain default values can be programmed, as well as tolerances that either will activate willings to warn against data insertion errors or exclude the erroneous input outright.

This is a direct way, based upon my experience, to engineer on the outside much of the risk pos from human error. Too many times I have seen the first officer calculating using the wrongful thrust setting, flap setting, wet/dry tables, or steady the runway and airport.

chiefly FMCs will swallow as frequently garbage as a pilot can fe them. I am persuaded that it is time for a radical overhaul of the part this system plays in critical flight operations. I believe the Airbus A380 now in design will address this issue. I am aware of a great deal of buck-passing in the past between FMC manufacturers, the aircraft manufacturers and the airlines as to what exactly this a whole should accomplish. I think this ill-defined relationship has l to the poorly unfolded product with which we are forced to operate today.