History of widebody airliner cross-sections

Read the forum code of contact

Member for

18 years 8 months

Posts: 1,101

The talk of the Airbus 380 and Boeing 787 makes me wonder how a good widebody cross-section is chosen.
B747
The first widebody ever was Boeing 747.

Anything before was narrowbody... the biggest had been Boeing 707, which was 376 cm wide outside, 6 seats across and single aisle.

Boeing 747 was 650 cm outside, 610 cm or so inside.

Initially, Boeing 747 used to fly 9 across in Coach, 3-4-2. However, later on 3-4-3 10-abreast seating appeared and has become standard. When and how?

Also, Boeing 747 had a huge attic - mostly empty and useless.

However, just behind the cockpit there was a small upper deck. At first, it was a lounge.

When and how did seats get there?

DC-10
DC-10 was the next widebody. 602 cm outside, something over 570 cm inside width.

I hear that it used to have 2-4-2 8-abreast layout in Coach for quite a long time.

Note that it was less than 40 cm narrower than B-747. In B-747, there is not quite space from 1 extra column with same aisle/seat widths. And there are still 2 aisles - so in 3-4-2 the extra seat is a middle seat over and above being narrower.

Was DC-10 felt to be more spacious than B-747?

Then, somehow, extra seat columns appeared. Some DC-10s fly 9 abreast in 3-4-2 configuration, some are 2-5-2, some are 3-3-3. When did it happen?

And, it is possible to add 10th seat column in 3-4-3. Finnair, which is a legacy, flies their MD-11s 10 abreast now and into future...

Tristar
The third widebody is Lockheed Tristar.

It seems pretty similar to DC-10. Outside width, 597 cm, is just 5 cm narrower than DC-10. Inside width I think still over 570 cm. So, less than 40 cm narrower than Boeing 747.

Tristar started 8 abreast just as DC-10. And Tristar, too, came to seat 9 abreast... and 10-abreast Tristar has also been seen.

Does anyone know just how tolerable is a 10-abreast Tristar?

Also, Tristar made heavy use of underbelly, even though this diminished luggage/cargo space. Lower deck galleys, with lifts and service doors and emergency escapes. And there were lower deck lounges, with integral airstairs (ahead of wing). There was an option of sellable seats on the lower deck - but apart from emergency escapes, this required extra reinforcement of the underbelly in case of a belly landing...

I think DC-10 and Boeing 747 also sometimes have lower deck galleys and airstairs.
Airbus 300
The next (fourth) widebody was Airbus 300.

The Airbus 300 is smaller than either Tristar or DC-10. It is 564 cm wide outside and 528 cm inside. Also, the passenger floor is relatively high, so the plane has a small wasted attic compared to Boeing 747, relatively roomy underbelly and steeply inwards curving sidewalls.

The standard seating is 8 abreast, as on DC-10 and Tristar - and although much less roomy (over 40 cm narrower...) it has lasted longer. 9 abreast has crept in, usually 3-3-3, but does not appear prevalent. I doubt 10 abreast would be possible.

Some Airbuses, like Lufthansa Airbus 340-600, use underbelly for toilets, so it is roomy enough.

Il-86
The next (fifth) widebody was Il-86. It has outside fuselage width 608 cm, so slightly wider than DC-10. Like Tristar, Il-86 makes heavy use of underbelly airstairs.

B-767
The next widebody was Boeing 767. It seems that Boeing had had trouble filling the huge Boeing 747-100, compared to smaller DC-10 and Tristar and had considered making a narrower all-new fuselage desing, but finding it too expensive, shrunk B-747 to get B747SP. However, eventually Boeing did design a new small widebody. B-767 is even smaller than Airbus 300, being 503 cm outside and 472 cm inside width - 56 cm narrower than Airbus 300. So, Boeing 767 normally has 7 abreast with double aisle.
The cross-section is vertically stretched, 541 cm high, so the underbelly height is comparatively large and close to what the bigger widebodies have.

It seems like some airlines can have and have had 8 abreast seats in a Boeing 767...

B-777
The next new widebody was B-777. It is 619 cm wide outside - wider than DC-10 and close to Boeing 747. The inside width is said to be 586 cm - so 24 cm less than Boeing 747.

9 abreast 777 is of course roomier than 10 abreast 747 (since the difference between the widths is less than the width of a seat). However, since there are 10-abreast seats even on Tristars, some airlines have 10 abreast on 777. Not the majority of airlines (yet?).

The cabin difference of 58 cm and 1 extra seat column compared to Airbus 330/340 has dubious valye for passenger comfort - the extra seat cannot be a convenient one. The sidewall slope is much broader on 777, so the width difference on shoulder or eye level is greater... and therefore, a B-777 has a big empty attic.

Future:A380
The first widebody not yet in service is Airbus 380.

The main deck is slightly wider than Boeing 747. Maximum width is 658 cm compared to 610 cm, so 48 cm wider. However, the maximum width is higher, so there is less extra width on floor and armrest level, more on eye level.

The "default" seating is 10 abreast in 3-4-3 - roomier than in a B747.

The upper deck is much wider than the upper deck of B-747 - but it still has steeply sloping sidewalls. As the shape is different, numbers are hard to compare with main decks of other widebodies, but the "default" is 8 abreast in 2-4-2, as on Airbus 300.

Could you have 11 seat columns on Airbus 380?

It could be more cramped than 10 abreast on Boeing 747. But there are planes more cramped than 10 abreast Boeing 747 - like 10 abreast Boeing 777, DC-10 or Tristar. Airbus 380 main deck is about 72 cm wider than Boeing 777, and close to 80 cm wider than DC-10 or Tristar. So, a 11-abreast Airbus 380 seems feasible, and perhaps more comfortable than 10-abreast B-777.

Not sure about upper deck, because of the sidewall slope - can or cannot you have 9 abreast there?

Airbus is to seat 853 people in Airbus 380 on 26th of March. Does anyone know what the seatmap and configuration might be like?
It is said to be 315 seats on upper and 538 on lower deck.

Future:B-787
B-787 is supposed to be begun in June this year - does anyone know the deadline for first flight?

It is said to be 574 cm wide outside. So, 10 cm wider than Airbus 300. But it would be elongated upwards, to have about 600 cm height outside - close to what DC-10 has. Also, it would have thin walls and the floor would be low, so there would be much extra space compared to A-300 - especially at eye level.

How do you think does the width of B-787 compare with Tristar?

Boeing advertised 8 abreast seating on B-787, said to be roomier than A-300. But it has turned out that most customers plan to have 9 abreast!

How comfortable would 9-abreast B-787 be?

And is it possible to have 10 abreast on B-787? It is not that much narrower than Tristar...

Original post

Member for

18 years 1 month

Posts: 565

The size of the aircraft is determined by what the customer wants,during new aircaft ventures,manufacturers ask the airlines what kind of aircraft they would like & in what configuration.Emirates is currently pushing boeing to stretch the 787,to make it the same size as a 777-200.

Member for

24 years 2 months

Posts: 4,887

The 747's width was based on the width of a standard shipping container. As you will know the 747 was designed as a USAF cargo plane and converted later to civilian use.

The A300's width is based on two standard aircraft cargo containers (LD3?) side by side.

Don't know about the other planes.

Member for

18 years 8 months

Posts: 1,101

The 747's width was based on the width of a standard shipping container. As you will know the 747 was designed as a USAF cargo plane and converted later to civilian use.

So, they took the standard shipping container for granted.

Can DC-10 and Tristar accommodate those standard containers?


The A300's width is based on two standard aircraft cargo containers (LD3?) side by side.


Which planes had those "standard aircraft cargo containers" been invented for?

Member for

24 years 2 months

Posts: 4,887

So, they took the standard shipping container for granted.
Yes, at the time the container was breaking through. At first the standard 20ft and 40ft containers where mostly a US Army innovation (well, that's what they claim, it was a Dutch lad that actually came up with the idea. The US Army just gave enough critical mass to make it popular). Since the US Army wanted to use these containers, and the 747 was originally intended for USAF use making the 747 compatibel with the container was just logical.

Can DC-10 and Tristar accommodate those standard containers?
No, I do not think they can. Even if they could, the cargo hatch is no way big enough. Perhaps a 20ft but you would have to wiggle it around whole lot before it gets in!

Which planes had those "standard aircraft cargo containers" been invented for?
Pretty much all of the jets! However, until the advent of the A300 the container would be used on one side of the hold, and the other side of the hold got another (smaller) container or loose cargo.