Cable cars inherently have the principle of 'extremely safe', why do accidents still occur?

Designed with a safe and durable mechanism, many cable car systems around the world still have unfortunate incidents.

Structure and operating principle of cable car

Typically, an overhead cable car consists of one or two fixed cables (called rail cables), a cable connected to the carousel (called a tow rope) and two passenger cabins. According to Raj Kumar, an expert in transportation mechanics, the cable car system has an "extremely safe " and tight mechanism.

In particular, the fixed cable - as its name suggests, acts to support the balance of the cabin while the system operates. "When the cable runs, we feel like the cabin slides on the cables. However, in reality, it is fixed to the majority of the system through a handle-like part ," Kumar shared.

Photo: The two fixed ropes of the cable car are outside, serving to stabilize and balance. The pull rope in the middle is connected to the motor, helping the cabin move.

To move, an electric motor will rotate the wheel attached to the pulley, like a pulley, allowing the cabin to move as desired.

The cable cars are built as a closed circular system. Accordingly, the cabins move from their destination and are pushed by a cable loop. When they reach their destination, they change direction, and continue to return to their starting place.

According to standard design, the station at the end of the cable car must be strong enough to hold the weight of the entire system, but sometimes the tension from the cable car is so great that it has to dissipate some force to the 'bollard' part, mounted on a stone anchor.

This is a detail often seen in cable car systems up mountains. Their job is to keep the cable tensioned, and not sag due to gravity.

To do this, the 'bollard' continuously moves up and down to balance the weight as hundreds of people enter/exit the cabin. Stone anchors are inserted into the mountain, creating solid support for the entire cable car system. On average, these anchors can withstand loads of up to 700 tons.

All mechanical systems, including the electric motors that provide propulsion, are usually located at the lower station.

The stone anchor is placed at the lowest part of the cable car system, helping to keep the rope taut.

Sometimes, we also often see "suspension gondola" (MDG) cable cars. In these systems, only one rope is used for support and propulsion. Cable cars of this type are often used for short distances, and with a limited number of people.

The advantage of the MDG cable car system is that installation and operating costs are cheaper. However, instead of just one upper station, there can be many intermediate stations to help the rope move continuously.

Why do cable cars still have accidents?

At least 14 people were killed and one child was seriously injured in a horrific accident in the mountains of northern Italy on May 23, 2021. (Photo: AP)

According to experts, a cable car system that operates smoothly, according to principles and ideal conditions rarely has problems.

However, there are many factors that can affect cable cars, one of which is environmental impact.

For example, in 2017, a serious cable car break occurred at the famous Gulmarg ski resort, Kashmir province, India. The cause was later determined to be bad weather. Specifically, strong winds uprooted large trees, which then fell into the cable car system, causing the cables to break.

However, there are also cases where incidents occur due to human error.

The ship carrying an oil rig accidentally got stuck in the cable car system in Singapore, killing 7 people. (Photo: ST).

Typically, in 1988, a US Marine Corps plane, flying at low altitude, cut through a ski lift in Cavalese, Dolomites region, killing 20 people.

In 1983, a ship carrying an oil rig accidentally got stuck in the cable car system in Singapore, causing 2 cabins to fall into the sea at a depth of 55m and 7 people died.

In 2018, at the Gudauri resort, Georgia, the cable car system suddenly changed direction and moved very quickly in the opposite direction, causing dozens of people to be thrown to the ground. The incident was later determined to be due to a technical error when operating the cable car.

Things to note when riding the cable car

Accident Care Organization (USA) offers many tips for tourists when traveling on the cable car. The first and foremost note is to increase attention. As soon as you step into the cable car boarding area, carefully observe the safety instructions given by the service operator.

Remember the embarkation and disembarkation rules and the location of emergency equipment, especially observing load limits. Some previous cable car accidents were caused by carrying more than the prescribed number of people, even double.

If there are seat belts in the cable car, use them. Seat belts will help passengers avoid impact in the cabin in the event of a collision or sudden stop.

In particular, passengers need to observe weather conditions. Severe weather such as high winds or ice can significantly increase the risk of accidents.

Meanwhile, according to recommendations from the CDC (USA), during the trip, passengers should sit still and avoid unnecessary movement, do not lean or stand when the cable car is going up and down.

If an incident occurs, passengers need to stay calm and follow the operator's instructions. First, check your options for contacting the service operator or emergency services if needed.

In case you suspect the cable car has fallen (the probability is very rare), if you are prepared in time, change your sitting position by bending your knees and holding on to the strongest part of the cabin.

Absolutely do not try to escape the cable car without professional help, it will be dangerous.