Patent ID: 7281418

Claim:
A method of operating an aircraft, the method comprising: before an aircraft is loaded with passengers and luggage, performing a first measuring to measure a load on front landing gear strut(s) and rear landing gear strut(s) in order to obtain first weight data; after the aircraft has been loaded with passengers and luggage, performing a second measuring to measure a load on front landing gear strut(s) and rear landing gear strut(s) in order to obtain second weight data; subtracting the first weight data from the second weight data, and optionally compensating for fuel added to the aircraft between the times of the first and second measuring steps, in order to determine a total weight of the passengers and luggage on the aircraft; determining whether the aircraft is supported by inclined or tilted ground such as a runway, and when it is determined that the aircraft is supported by inclined or tilted ground then adjusting the total weight determined based on the incline or tilt of the ground; comparing the total weight of the passengers and luggage on the aircraft with a predetermined threshold, and if the total weight of the passengers and luggage exceeds the predetermined threshold then actuating an alarm; and wherein a floating laser is provided in the plane for determining whether the aircraft is supported by inclined or tilted ground, and wherein a plurality of targets or target areas are provided and tilt or incline of the ground supporting the aircraft is determined based on which of the targets or target areas is hit with a laser beam from the floating laser.