Strange Vehicles: Rhein-Flugzeugbau GmbH X-114 ‘Airfoilboat’



RFG X-114 Airfoilboat

The X-114 protototype, or ‘Airfoilboat’ as it was known, was a German aircraft which was developed by Rhein-Flugzeugbau GmbH (RFG), an affiliate of the aircraft manufacturer Fokker. The X-114 Airfoilboat was designed by Dr Alexander Lippisch, an early pioneer in the field of aerodynamics. One of his previous creations included a delta-wing aircraft developed in the early ’30s which led to the rocket-powered Messerschmitt Me 163.

After the Second World War he moved to the US to continue his work. During the ’60s he was employed by the Collins Company designing high-speed watercraft. One of the designs he worked on was a catamaran. However the vessel continually tried to get airborne. Leading Lippisch to proclaim; “If the things insist on flying, let them fly”. It was from this moment he devoted his time to further exploring the ground effect principle. For those who don’t know, ‘ground effect’ is the name given to the phenomena where low flying aircraft experience additional lift as they get closer to the ground. It’s very complicated stuff, and it’d take someone a hell of a lot smarter than me to properly explain it. But that should be enough to get you through this article.

The X-114 prototype was the third aircraft of the program to be developed throughout the late ’60 and 1970s. The previous aircraft were designated the X-112 and the X-113 Am. The X-114 Airfoilboat was considerably larger than the first two prototypes, and could carry up to six people.

RFG X-114 Airfoilboat

The X-114 first flew on April 15, 1977. For the next few weeks it was extensively tested and trialed. The unique properties of the aircraft meant there was little to compare it against in terms of performance or handling. However it was deemed stable, as well as easy to fly and land. The X-114 has a wingspan of 7 metres (23 feet), a top speed of 93 mph (150 km/h), and a range of 1240 miles (2,000 km). It is powered by a four-cylinder Lycoming engine turning a propeller housed within a protective shroud. When fitted with a specially designed detachable undercarriage the X-114 can take-off and land on solid ground.

While aircraft which take advantage of ground effect, or ekranoplans as they are often called, are nothing new – the Russians went mental for the things during the cold war – the X114 was a little different in that it could achieve much higher altitudes than most similar aircraft. The X-113 Am, for example, managed to achieve 800 metres (2,624 feet) on one flight.

The versatile design of the X-114 has interested both the military as well as civilian operators. A newer version of the aircraft, called the RFB-215, already exists on paper. Several countries in South East Asia, as well as Canada, have shown interest in the design.

RFG X-114 Airfoilboat drawing

6 Comments

Leave a Reply