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NAMC YS-11

Japan's first commercial aircraft designed after the second world war was a twin turboprop transport aircraft of the Nippon Aircraft Manufacturing Company (NAMC). In apprearance the YS-11 is quite similar to the Avro/Hawker Siddeley 748, but then larger. Both aircraft share low mounted, long span straight wings. The vertical stabiliser has a trapezium shape with a large dorsal fin in front. Both aircraft are powered by Rolls Royce Dart engines, in both cases housed in similarly shaped nacelles above the wings with room for the two wheel main gear below the wings. The nose gear also has two wheels. The final similarity is the rear fuselage tapering into a pointed tail cone. There are differences as well, as the YS-11 has small rectangular cabin windows. In addition, the cockpit windows all have about the same size and include no eyebrow window. Other differences are smaller.

The cockpit windows of the YS-11 are flat and all have about the same size. Note the relatively long but blunt nose and the cabin door sliding open to the right.

The rounded nacelles of the YS-11 combine the long, slender Rolls Royce Dart engine at the top (with their typical rind shaped intake) and the housing for the main gear below.

Different versions

The different versions of the YS-11 can be distinguished by look at

  • the presence of a large cargo door in the left forward fuselage
  • the presence of and number of radomes on top of ans underneath the fuselage
  • the shape of the engine nacelles
  • the opening mechanism of the forward cabin door

YS-11, YS-11-100 & YS-11FC

The first version of the YS-11, the YS-11 prototypes and the YS-11-100 production version, is characterised by the forward cabin door. It hinges at the side and swing open to the left.

For the calibration of navigation systems the Japanese air force acquired three YS-11FCs. Two of these were converted YS-11-100s and one an YS-11A-200. Externally, they are not different except for the red-white checkered colour scheme.

The prototype YS-11 (and first production version) has cabin doors that gine at the side and swing to the left, as demonstrated here.

The red and white colours on this YS-11FC are the best way to recognise this versions, as we have found no other features.

YS-11A-200, YS-11A-500, YS-11NT & YS-11P

The main pure passenger versions were the YS-11A-200 and YS-A-500, the latter being a higher weight variant of the former. Both have compared to the YS-11-100 cabin doors that slide open to the right instead left hinged ones. See the detail photo further up.

The VIP version of the Japanese Air Self-Defense Force (JASDF) is designated YS-11P, while the Navigation Trainer is called YS-11NT.

The most popular versions of the YS-11 were the YS-11A-200 and the YS-11A-500 shown here.

YS-11A-300 & YS-11A-600

A large cargo door in the left forward fuselage and less cabin windows are the key features of the combi version of the YS-11, the YS-11A-300. The -600 is the same except for its higher maximum take-off weight.

Note: cargo conversions of the YS-11A-200 and -500 often have a large cargo door in the left rear fuselage.

In the left forward fuselage of this YS-11A-300 the large cargo door is clearly visible. (photo: Christian Volpati/WikiMedia)

YS-11EA (YS-11A-400)

Of course the Japanese military were one of the main customers of the YS-11. This is an electronic warfare version, based on the YS-11A-400. It has external blade antennas, two on top of the fuselage, in the middle, and four underneath, before and after the wings. The YS-11EA aircraft were fitted with General Electric T64 turboprop engines soon after delivery. These have different nacelles and three blade props.

For an electronic warfare aircraft the YS-11EA has limited external characteristics, except some blade antennas in the middle of the fuselage. Note the different nacelles and three blade props of the T64 engines.

YS-11EB (YS-11A-400)

The electronic intelligence (ELINT) version, designated YS-11EB by the JASDF, has many bulges on top of and underneath the fuselage. This makes it easy to recognise. Like the YS-11EA it is equipped with General Electric T64 turboprop engines with three blade propellers.

The four large bulges of the YS-11EB make it easy to distinguish from any other YS-11 variant.

YS-11M-A (YS-11A-400)

The cargo version of the Japanese Maritime Self-Defense Force (JMSDF) has a large cargo door in the left rear fuselage. It still has cabin windows though.

Seen from the right the YS-11M-A cannot be distinguished from most other variants.

Only on the left side you can clearly see the large cargo door in the left rear fuselage that characterises the YS-11M-A of the JMSDF (photo: Ken H - @chippyho/WikiMedia)

YS-11T-A (YS-11A-400)

Training for the 'real' maritime patrol aircraft of the Japanese Maritime Self-Defense Force (JMSDF) was conducted on a special variant of the YS-11, the YS-11T-A. Its key recognition point is a radome underneath the forward fuselage. Additionally, the YS-11T-A has only a few cabin windows.

The large black radome underneath the fuselage of the YS-11T-A can hardly be missed on this photo, as is the lack of many cabin windows.

Confusion possible with

Avro/Hawker-Siddeley/British Aerospace 748

ys 22a 500

The 748 has many similar features but is smaller than the YS-11. Additionally, the 748 has less but larger oval cabin windows, and cockpit windows all of about the same size.

British Aerospace ATP

baeatp f

The British Aerospace ATP is a larger derivative of the 748, hence being of about the same size as the YS-11 and also having small rectangular cabin windows. The ATP has a more poin­ted nose, the cockpit windows of the 748, different nacelles, six blade props and a swept trailing edge of the vertical stabiliser.

Grumman G.159 Gulfstream I

g.159

Although much smaller the Gulfstream I still has similar elements as the YS-11, especially the engine nacelles. However, you can easily keep them apart by the fewer but much larger oval cabin windows of the Gulf.

Convairliner family

convair 580f

Given the same basic configu­ra­tion the Convair­liners could be mixed up with the YS-11, but this is less likely given the rectangular cabin windows, more curved leading edge of the vertical stabiliser and dorsal fin, different nacelles and upward opening cabin door of the Convair 240, 340, 440, 580 and 600/640.