Pilots make mistakes David Connolly's letter (Flight International, 13-19 July) fails to suggest how pilots are supposed to insert V figures in the flight management computer other than by using the number keys. Incorrect entries such as this should be picked up by the other pilot. Is this not one of the reasons that commercial aircraft are required to have two pilots? No matter how a manufacturer designs an aircraft, some humans will find a way of making a mistake, or failing to follow the correct procedure, with potentially disastrous consequences. Several years ago, Airbus introduced guards over the hydraulic pump switches after pilots of a well-known Far East airline switched off all the hydraulic pumps when attempting to transfer fuel. More recently, pilots of another airline placed the thrust levers of an Airbus A330 in the incorrect position for take-off and neither pilot noticed the blank flight-mode annunicator in the primary flight display, which should have read, for example, "FLEX 50/SRS/RWY" and which should be read by the pilot flying and responded to by a "check" from the other pilot. What is the purpose of a flightdeck manned by two pilots if one pilot does not notice, and respond to, fundamental mistakes by the other? Paul Buckland Kowloon, Hong Kong
No bad design Safety officers are responsible for investigations, the outcome of which must be for the sake of safety improvements and not to blame pilots. But I disagree with two of your letters, "Flawed flight display" and "Bad design" (Flight International, 6-12 July). As an Airbus A320 captain and former A330 first officer, I hardly accept that there is a design flaw on the sidestick symbol on the primary flight displays and for subsequent events on the Emirates incident. As we perform low-visibility training and operate sometimes in marginal weather conditions, from runways as short as 1,300m (4,300ft), then during rotation pitch is the main parameter, as with any jet, and the sidestick index is never regarded, even approaching V1 and VR speeds. Visual confusion, misunderstanding or, even worse, thinking that fly-by-wire Airbuses are video games instead of jet aircraft, can not be called interface errors, but be attributed to operational discipline on highly automated aircraft. Piloting skills should maintain safety and efficiency throughout. Just pull the stick, follow the normal rate of rotation and the flight director, and not be "confused" about the meaning of that "iron cross" on the horizon. Capt Alex Frischmann São Paulo, Brazil
Defence waste How right Lance Cole is (Flight International, 20-26 July). The waste in the UK defence industry is close to criminal. Now we have a "three-year experiment to gauge the validity of the MOP concept" and "several companies will be awarded contracts". Just take a trip to Hendon and look for a thing called called "Grand Slam". It works, too. Alan Heywood Hatfield, Hertfordshire, UK
Sniffing it out I understand that modern explosive detectors can sniff out minute traces given off by explosives. If this is the case, surely it would be cheap, efficient, and prudent for aircraft manufacturers and airlines to install explosive sensors in aircraft air-conditioning system ducting. Duncan Spence Seattle, Washington, USA
Source: Flight International
