Refer to figures.
Dry Operating Mass (DOM) is the total mass of the helicopter ready for a specific type of operation excluding all usable fuel and traffic load. This mass includes the items below, known as Variable Load (VL):

• Crew and crew baggage
• Catering and removable passenger service equipment
• Portable water and lavatory chemicals
• Food and beverages.

Take-Off Mass (TOM) is the mass of a helicopter including everything and everyone contained within it at the start of the take-off run.

Useful Load (UL) consists of the fuel onboard for a flight and traffic load.

Traffic load (TL) in a helicopter refers to the number of passengers or cargo that the aircraft is carrying at a given time. It is used to determine the weight and balance of the helicopter, which is important for safe flight. The maximum traffic load of a helicopter is determined by its design and is specified in its flight manual.

Zero Fuel Mass (ZFM) is the term used to describe the DOM plus TL but excluding usable fuel.

Take off fuel is derived:

• Take off fuel = Block fuel – taxi fuel = 980 kg – 15 kg = 965 kg.

Calculate TL by:

• TL = Allowed Take Off Mass – DOM – take off fuel= 8 450 kg – 5 210 kg – 965 kg
• TL = 2 275 kg.

NOTES:

1. Taxi fuel is well below the MSTM and used prior take off therefore, not part of PLTOM.
2. The most limiting mass shall be used in the calculation to provide safe operation, in this case theAllowed Take Off Mass is the most limiting mass.