How much does an aircraft weigh? There is no single answer. An airliner constantly changes weight during operation: passengers board, baggage and cargo are loaded, fuel is added – and then burned during flight. Aviation therefore uses several clearly defined weight figures.
Among the most important are empty or operating empty weight, zero fuel weight, take-off weight and maximum take-off weight.
What does empty weight mean?
In simplified terms, empty weight describes the aircraft without commercial payload and without the usable fuel required for the flight. In practice, several definitions are used, including Basic Empty Weight and Operating Empty Weight. Depending on the definition, crew, operating fluids or specific equipment may already be included.
This is why an Airbus A320 or Boeing 737 does not necessarily have one universal “empty weight”. Airlines use different cabin layouts, seats, galleys, entertainment systems and other equipment, all of which influence operating empty weight.
What is Zero Fuel Weight?
Zero Fuel Weight is the mass of the aircraft without usable fuel. It therefore includes the aircraft itself plus crew, passengers, baggage and cargo. Maximum Zero Fuel Weight, or MZFW, defines the upper permitted limit.
For the A320neo, Airbus currently lists a maximum zero fuel weight of 65.3 tonnes, while maximum take-off weight reaches 79.0 tonnes.
Take-off Weight and MTOW
Actual Take-off Weight is the mass of the aircraft when the take-off run begins. Maximum Take-off Weight, or MTOW, is the certified upper limit. Airbus defines Maximum Design Takeoff Weight as the maximum weight at the beginning of the take-off run as limited by aircraft strength and airworthiness requirements.
Aircraft do not automatically depart at MTOW. The operationally permitted take-off weight may be lower depending on airport elevation, temperature, wind, runway length, slope and runway condition. EASA rules explicitly require such factors to be considered when determining take-off mass.
Why aircraft need several weight limits
Each limit protects different parts of the aircraft and different phases of operation. MTOW is closely linked to structure and take-off performance. Maximum Landing Weight limits the mass permitted at landing. Maximum Zero Fuel Weight protects the airframe against excessive structural loads when little or no usable fuel is carried.
So before asking “How much does an aircraft weigh?”, the first question should be: at which point in the flight?
Read more:
How Much Does a Boeing 737 Weigh? Comparing the 737-800 and 737 MAX
How Much Does an Airbus A320 Weigh? Key A320neo Weight Figures Explained