So that flights can be conducted safely, load distribution in an airplane is essential. Before take-off, pilots have to ensure that the masses on board - luggage, passengers and fuel - are well distributed.
To understand this issue, we spoke to an Air France captain at the company’s headquarters in Paris. Paul Thevenon-Rousseau explains: "When you take a pen and balance it on your finger, you have determined the pen’s centre of gravity. Well, for a plane it’s the same thing, depending on the load distribution, there is a centre of gravity to which forces are applied. What are the consequences on the flight if the centre of gravity is a little forward? Well, the plane is extremely stable but unwieldy. When the centre of gravity moves backwards, the more we find maneouvrability, but instability."
It’s therefore necessary that the centre of gravity (C.G.) is neither too far back, nor too far forward, but within the limits defined by the aircraft manufacturer. Nevertheless, the centre of gravity is usually preferred a little toward the rear because it saves more fuel.
To help pilots in this delicate phase that requires precision in a relatively short time period, Air France has a documentation development centre such as this one, which produces the Centralized Loading Document (CLD). Here, thanks to a software, they calculate the estimated load for a specific flight, after which, the data is sent directly to the cockpit of the aircraft concerned where it is verified by the pilots.
And if you’ve ever wondered why you’ve been refused a change of place during a flight, towards the front for example, it’s because of this famous load distribution problem. One passenger in fact varies the balance by 0.1%.