Hands-on air traffic control

In his two recent letters (Flight International, 4-10 May and 15-21 June) on automation, David Parkinson effectively highlights the dilemma about the future role of pilots and air traffic controllers. Are they to be audience or actors?

The technology to automate air traffic control and aircraft flight to the extent advocated by Mr Parkinson already exists. It features in much of the thinking behind the development of new air traffic systems in Europe and the USA. However, to my knowledge, none of these developments envisages removing humans from the thinking process. And nor should they.

Humans are not good at monitoring the routine and repetitious. We need to be involved, preferably at a decision-making level, in which case, we need to be both trained and current in such decision making, so that our output is correct and largely instinctive.

Mr Parkinson's suggestion that controllers should be relegated to the role of managing airspace and to intervening in the control of aircraft to handle exceptions and emergencies is therefore flawed.

Effective intervention requires controllers to be immersed in the "picture", as opposed to merely monitoring it. And technology can fail. When the flightplan data processing system at West Drayton fell over recently, controllers would have been able to adapt and cope because they were "hands-on" and because their expertise was based on past controlling experience. I defy technology to provide safe redundancy to this degree. Mike Strong Brussels, Belgium

Keeping fuel balanced

Graham Smith, in his letter about hull losses, some of which were due to fuel mismanagement (Flight International, 15-21 June), says: "An idiot-proof fuel system would seem essential." I agree, and believe it will eventually be mandated for light aircraft.

I worked with Piper in the late 1990s to design a fuel system for its new turbine-powered Piper Meridian. Our goal was to design a system that would not require a fuel selector, maintain fuel balance within 11kg (25lb), and virtually remove fuel management from the cockpit. These goals were accomplished and almost 200 aircraft have been delivered since certification.

After the Meridian programme, I contacted the US National Transportation Safety Board (NTSB) to gauge how frequently accidents occur on light aircraft due to fuel starvation, with fuel still available. The compiled list for 2000 revealed that there were 30 accidents among Beechcraft, Cessna, Grumman, Mooney and Piper types. Of these accidents, 19 were related to fuel tank selector operation and 11 to fuel management, such as switching tanks and balancing fuel burn.

The majority of micro-jets being developed will be certificated for single-pilot operation and flown by pilot/owners that fly infrequently. With this combination, and speeds approaching 400kt (740km/h), the last thing a pilot needs is fuel management concerns and their potentially fatal consequences. John Flinchum Vero Beach, Florida, USA

Hidden flaws

Your correspondents Omar Husseini and Lance Cole (Flight International, 6-12 July) make cogent and valid critiques of the Airbus A340 primary flight display design. But there is another "questionable" design feature that has on occasion surfaced.

On 14 June 2002, an Air Canada Airbus A330-300 was leaving Frankfurt for Montreal and suffered a tailstrike that was to be mirrored by Singapore Airlines in Auckland in March 2003, in symptoms, although not in severity. In Frankfurt the pilot not flying inserted a V1 of 126kt (233km/h) instead of the correct 156kt in the flight management computer. The "2" being above the "5" in the keypad probably contributed to this.

On the primary flight display speed tape these values are represented as a green "1" for V1 and a blue circle for VR - a more esoteric feature than that on other designs. The V1/VR spread on this A330 and the A340 is usually fairly close, so much so that the blue circle will often be superimposed on the "1". Being "accustomed" to calling "V1" and "rotate" in rapid succession, the pilot not flying called V1 as the speed tape reference index approached the "1" and called rotate immediately thereafter, when the blue circle would have been out of view at 157kt.

Flawed flight display? Blunder or bad design? It seems to be an unhealthy mix of the two, where the design offers an open invitation to blunder. David Connolly Brussels, Belgium

Tourist trapped

I wonder whether the USA is worried about losing its tourist industry. Arriving at Houston recently, my family and I queued at immigration for three and a half hours, missing three connecting flights, just to have somebody ask where we had come from and why we were visiting the USA.

We had endured thorough checks at Gatwick and had been nowhere other than on an aeroplane and in the queue, with hundreds of others from three or four flights. Can the authorities sort out a fast-track method for people who are obviously no risk? David Hayfield Birchington, Kent, UK

Source: Flight International