The McDonnell Douglas MD-11 is the forgotten third aircraft in the Airbus A340 and Boeing 777 battle. While it burned more fuel than the two above, it had a more extended range and could easily match the passenger capacity. What was the MD-11, and how did it compare to Airbus' A340 at the time?

Delta Air Lines MD-11
Delta held 17 MD-11 units between 1990 and 2004 and the length of the carrier's relationship with the plane isn't much longer than the production run of the type. Photo: Getty Images

How will we be comparing the aircraft?

To compare these two aircraft, we will take on the mantle of a carrier looking for a new plane (back when these two were new). We will look at the range and passenger capacity and any other essential factors.

We won't be looking at passenger comforts. While they are nice, they won't contribute to our financial bottom line as an airline and thus shouldn't take the front seat in our decision-making process.

We will also be looking at the A340-200 and -300 variants, and not considering the A340-500 or -600. This is because they were further designs that came out with better technology and well after the MD-11 finished development. If we wanted to make it fair, we could include the MD-11 further modifications, but the information is sparse about their specifics.

Let's begin!

Virgin A340
Virgin Atlantic also no longer operates the Airbus A340 type. Photo: Getty Images

Passengers

There are three passenger configurations for the MD-11.

  • 298 passengers in three classes (16 in first class + 56 in business class + 226 economy class).
  • 323 passengers in a two-class configuration (34 in business class + 289 economy class passengers). The recommended configuration was a 2-5-2 seat layout.
  • 410 passengers in economy class with 10-abreast seating configuration.

The A340 series on the other hand:

  • A340-200 can seat 250 passengers in a three-class layout, 303 passengers in a two-class layout (30 in first class + 273 in economy) and has an exit limit of 375 passengers. This can be upgraded to 420 with the installation of more doors, but this wasn't a factory option.
  • A340-300 can carry 290 passengers in a three-class layout, 335 passengers in two cabins (30 in first class + 305 in economy), and then up to 375 all-economy (420 with the additional retrofitted doors).

Judging by the numbers, we can see that the MD-11 is better suited for the old fashioned three-class layout, with the A340 upgraded for a two-class configuration. On the whole, the MD-11 is a better aircraft for passenger seats, and 'out-of-the-box' can carry more passengers.

The 2-4-2 configuration on Air Belgium's A340s. Photo: Air Belgium

Range

When it comes to these two aircraft, which has a better range?

  • The MD-11 has a range of 6,725 nautical miles (12,455 km)
  • The Airbus A340-200 has a range of 6,700 nautical miles (12,400 km), and the Airbus A340-300 has a range of 7,300 nautical miles (13,500 km).

By these numbers, we can see that the MD-11 was well suited to match its contemporaries. The A340-300 could fly further, but few routes desperately needed another 1,100 km when comparing between the two types of aircraft.

Four engines vs. three engines

Let's talk about the most significant difference between the two aircraft. How does having three engines on the MD-11 compare to the four engines on the A340?

Lufthansa A340-600
Lufthansa ordered 24 A340-600 aircraft. Photo: Lufthansa

Looking at fuel efficiency:

  • The MD-11 has a fuel capacity of 117.3t / 258,721 lb
  • The Airbus A340-200 and -300 have a fuel capacity of 110.4 t / 243,395 lb

The MD-11 has a cruise of Mach 0.89, and the Airbus A340 has a cruise of Mach 0.86. While not significantly different, it does add up over time. The MD-11, when operational, allowed Singapore to fly from its hub airport to London in an hour less than the A340. 

Judging by the numbers, we can see that the MD-11 needs to carry more fuel to fly faster to a slightly smaller range than the -300, but is more fuel-efficient than the -200. Right in the middle.

Delta Air Lines MD-11 Tail
The MD-11 engine was not a fuel-saving engine compared to the other four-engined aircraft. Photo: Delta Flight Museum

In the end, the MD-11 doesn't hold up against the A340. While its three engines make it seem like it has one less hungry engine to feed, it needs more fuel to fly the same distance as the Airbus A340-200, and the A340-300 is even more superior with more passengers and more range.

The Airbus A340 may have won against the MD-11, but a few years later, the Boeing 777 would enter the market and steal the crown. 

What do you think? Let us know in the comments.