Major airlines with the oldest fleet: Are older planes less reliable to fly?

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So if planes are built to last more or less indefinitely, why are they retired after just 30-odd years – or in many cases sooner?

"Planes are sold, traded or mothballed not because they've grown old and are falling apart, but because they've become uneconomical to operate," said Smith.

"Aircraft are tailored to particular roles and markets, and there's a fragile balance between whether it makes or loses money. Poor performance means quick exit to the sales block. To another carrier with different costs, routes and needs, that same aircraft might be profitable."

An aircraft's dwindling economic value tends to be related to its age – and with a slew of new fuel-efficient aircraft coming onto the market, maintaining older jets often makes less financial sense.

Modern jets also tend to be quieter, more comfortable and equipped to a higher specification than their predecessors, which usually means a better experience for passengers.

So which carriers have the oldest planes? According to airfleets.net – a website which monitors most major airlines – of the world's 30 largest carriers (based on passenger numbers), Delta Airlines has the most mature planes with an average age of 17 years.

Air Canada and United Airlines are reckoned to have the second and third oldest fleets, with an average age of 14.2 and 14.1 years respectively.

Qantas has the 10th oldest fleet in the skies, with an average age of 9.7 years. That average will come down over the next 12 months as the airline begins taking delivering of new Boeing 787 Dreamliners, which will likely start replacing the airline's ageing 747 jumbo jets.

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Data is approximate and is not available for all carriers, including Turkish Airlines, which is considered one of the world's largest airlines.

At the other end of the spectrum is Aeroflot, which has the youngest planes with an average age of just 4.2 years; Hainan Airlines and China Eastern Airlines have the second and third freshest fleets with an average age of 4.9 and 5.3 years respectively.

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With a few exceptions – including Ryanair and EasyJet – European and North American airlines tend to have the oldest jets, while Asian and Middle Eastern carriers generally boast the youngest.

Incidentally, Jet2 – which was involved in the aforementioned forced landings but is not considered one of the world's 30 largest airlines – has a fleet age of 16.8 years, which is at the older end of the spectrum.

Which major airline has the oldest fleet?

1 Delta Airlines 17 years
2 Air Canada 14.2 years
3 United Airlines 14.1 years
4 British Airways 13.2 years
5 Air France 12.6 years
6 Lufthansa 11.5 years
- Southwest Airlines 11.5 years
8 KLM 10.7 years
9 American Airlines 10.3 years
10 Qantas 9.7 years
11 Thai Airways 9.6 years
12 All Nippon Airways 9.4 years
13 Jet Blue Airways 9.3 years
14 Korean Air 9.2 years
15 Japan Airlines 8.7 years
16 LATAM Brazil 8.1 years
- Singapore Airlines 8.1 years
18 Cathay Pacific 7.7 years
19 EasyJet (UK) 7.2 years
20 China Southern Airlines 6.9 years
21 Ryanair 6.5 years
22 Air China 6.3 years
23 Etihad 6.1 years
- Qatar Airways 6.1 years
25 Saudi Arabian Airlines 5.9 years
26 Emirates 5.4 years
27 China Eastern Airlines 5.3 years
28 Hainan Airlines 4.9 years
29 Aeroflot 4.2 years
30 Turkish Airlines No data

*Ranking Airline Average age of fleet

The Telegraph, London

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