The mass of an aircraft and the location of its centre of gravity are vital information required before commencement of any flight.
The AFM (AFM) contains critical mass and balance data, for example:
Maximum empty mass;
Maximum fuel load and effect on centre of gravity of fuel in different tanks;
Maximum freight or passenger load in any compartment and effect on centre of gravity;
Maximum mass permitted for take-off and landing;
Critical positions (forward and aft) of centre of gravity for take-off, in flight and for landing.
Knowing the actual aircraft empty weight and position of its centre of gravity, the passenger and freight load and the planned fuel load, the actual weight of the aircraft and location of is centre of gravity can be calculated for any point in flight.
The calculated or actual take-off mass must not exceed:
CL60, Teterboro USA, 2005: On 2 February 2005, a Challenger, belonging to Platinum Jet Management, crashed after taking off from Teterboro, New jersey, USA. The aircraft's center of gravity was well forward of the forward takeoff limit.