Incorrect take-off weight entered in flight computer

Re Virgin A340 incident at Heathrow where crew entered incorrect takeoff weight into flight computer which then gave too low rotation speed, almost resulting in failed take-off (and Fight magazine's editorial on the subject). I'm a non-flying layman, but seems to me it should be possible to determine static aircraft weight by measuring deflection of the landing gear (basically a large spring balance). Alternatively fit strain gauges on landing gear struts. This can then be automatically entered to flight computer, or at least used to cross-check calculated take-off weight. By measuring weight resting on each set of main gear plus nose gear you should also be able to check weight distribution or center of gravity (if you care). I'm astonished if this isn't done already.

• Filed under: safety weight take-off

Variances of this act have occurred, namely Emirates at JNB and then MEL last year. The MEL incident was serious and could have ended in a crash. The incident prompted changes at Emirates: http://www.flightglobal.com/articles/2009/04/30/325895/emirates-changes-procedures-after-melbourne-a340-500.html

Significant gross errors should surely be readily detected by simple "common-sense". If the flight is of so many hours duration, with approx. X percentage of passengers and so much cargo, then the take-off weight has to be so many tonnes. The Vr figure is not that critical that the airspeed has to be exact to a knot or so. The pilots should be able to simply glance at the weight figure to determine if it looks "sensible" for the route and fuel required. And, should the wrong Vr speed be called, surely the pilot flying should be able to detect if the aircraft is not responding in an appropriate manner...if it not, lower the nose, use all the available power you have and continue accelerating...we used to call it "airmanship" .....

I totally agree with dakota's point...