Why is carry-on luggage often limited in size and weight?

Carry-on luggage on airplanes consists of two types: checked luggage and carry-on luggage. Checked luggage is handed over to airline staff during the check-in process. On the other hand, carry-on luggage includes all the items you bring into the airplane cabin and manage yourself during transportation.

While European and American airlines may allow you to carry carry-on luggage weighing between 5 – 10kg, 12 – 18kg, and some even allow up to 23kg, Asian airlines like those in Vietnam typically have a carry-on luggage weight limit of no more than 7kg. Why is this regulation in place?

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Ensuring the Proper Weight for Aircraft

According to airlines, the regulation of the weight and dimensions of carry-on luggage is aimed at ensuring the structural integrity of the overhead luggage compartments (depending on the type of aircraft) – a factor that also affects the safety of flights. One of the civilian aircraft models produced worldwide, the Boeing 777, can accommodate 314 to 451 passengers, while the Airbus A380 can hold approximately 820 passengers.

Scientists have calculated the weight of the passenger compartment (above), the cargo hold (below, used for checked luggage), balanced the number of passengers, and considered various aircraft parameters, including the wings and engines. The chosen numbers fall within the limits that ensure stable takeoff and landing of the aircraft. For airlines that allow more than 7kg of carry-on luggage, the number of passengers has been calculated accordingly.

Ensuring the Proper Weight for Aircraft
Ensuring the Proper Weight for Aircraft

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Easy Handling of Small Carry-On Bags

A weight range of 7-8 kg is also suitable for transporting by an average-sized person. You can lift it, lower it into the storage compartment, and move the luggage easily. Some studies have shown that the size and weight of items determine the time passengers take to board the aircraft. If your suitcase or bag is too large or bulky, self-transport can be challenging, sometimes causing delays and inconveniences for those around you.

Some airlines in China only allow each passenger to carry 5 kg. Part of the reason is that airports in this country are consistently overloaded. Passengers with less luggage lead to faster movement, saving time in airport operations.

The dimensions of 20 x 40 x 55 cm have also been calculated to fit the overhead luggage compartments, ensuring that items can be stowed securely without falling out and posing a danger to passengers during the aircraft’s movement.

Easy Handling of Small Carry-On Bags
Easy Handling of Small Carry-On Bags

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Fuel Efficiency for Flights

In addition to scientific and safety considerations, commercial airlines also take into account fuel efficiency when setting regulations for carry-on luggage. Limiting the weight of passengers’ belongings is one effective measure to reduce fuel consumption. If an aircraft carries too much luggage, it can lead to higher fuel consumption and increased costs. Consequently, ticket prices may have to be adjusted, becoming less attractive to passengers.

To avoid fines for excess baggage, passengers need to carefully calculate the allowed weight limit to avoid inconvenience and time-consuming hassles. In addition to size and weight, there are strict regulations regarding carry-on luggage, such as the prohibition of metallic, flammable, and explosive materials, as well as liquids. At each airport, there are trays available for weighing and measuring luggage free of charge. Before checking in, it’s advisable to weigh and measure your items to ensure they comply with the regulations.

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So, the reason why carry-on luggage is often restricted in size and weight is because it ensures the safety of the aircraft in terms of load-bearing capacity and the dimensions of the overhead luggage compartments. 7kg is also an ideal weight for transportation, for lifting it into and out of the storage compartment. From a cost perspective, carrying more and heavier carry-on luggage incurs additional transportation costs. Each airline has its own regulations regarding the weight of carry-on luggage, so when purchasing plane tickets, be sure to inquire about this.

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