Rhein-Flugzeugbau X-113

from Wikipedia, the free encyclopedia
RFB X-113 Am
The X-113 at the 1973 Paris Air Show
The X-113 at the 1973 Paris Air Show
Type: Experimental ground effect aircraft
Design country:
Manufacturer:

Rhine aircraft construction

First flight:

October 1970

Number of pieces:

1

The RFB X-113 was an experimental ground-effect aircraft designed by Alexander Lippisch and built at Rhein-Flugzeugbau .

history

The X-113 is based on the first Lippisch design of a ground-effect vehicle, the X-112 . Lippisch himself named the vehicle Aerofoilboot after the English word for wing profile . The X-112 (approval: N5961V) was designed by him in Cedar Rapids (Iowa) and reached a speed of 126 km / h in 1963 with an 18 kW (25 hp) engine.

Lippisch developed the X-112 from 1959 to 1963 at the request of his then employer Arthur A. Collins , the owner of the Collins Radio Company , who needed a large motorboat made only of plastic in order to be able to test his electronic instruments without interference. In towing tests without a built-in motor, a scale built into the line showed that the resistance was only 4 to 5% of the total weight, which corresponds to a glide ratio of 20 to 25.

After a lecture in Bonn in 1965, the development of the X-112 also met with interest in Germany. a. at the Federal Ministry of Defense and at Rhein-Flugzeugbau, which took over the production of the airframe in what was then a very modern GRP design. A second prototype was then built in Germany in 1970 with a 29 kW (40 hp) engine and named X-113 (approval: D-9568). The vehicle reached a top speed of 140 km / h. In an interview, Lippisch described such a vehicle as a “Flährzeug”, a mixture of a vehicle and an airplane.

Ground effect

To take advantage of the ground effect, the vehicle “flies” about 20–40 cm above the surface of the water. The amount of air carried by the ground effect vehicle then consists of two parts. Part of it is the accumulated air under the wing, most of it is moved with the boat. The smaller part of the air leaves the space under the wing, but is continuously replaced by air flowing in at the wing nose. The essential part remains under the wing and creates a pressure there that almost corresponds to the dynamic pressure . The air mass under the wing forms, so to speak, an air roll on which the vehicle rolls forward like on a lubricant. For the effectiveness of the effect, the wing chord and less the wingspan is decisive. Furthermore, in contrast to the conditions in an airplane, there is a practically eddy-free flow around the boat. Test results show that the existing manual control of the system can only be sustained for a short time. The human factor as a limitation of the system meant that the required ground effect flight characteristics were only available for a short time. Computer-aided control and regulation systems were not yet state of the art in aircraft at that time.

construction

The cell was designed as a GRP construction. The floating plant was made of solid-polystyrene cores and the side walls of the central float in a hard foam - sandwich construction made. For the supporting structure, RFB developed a longitudinal tube-shell construction especially for this boat. All hoses are individually sealed and thus ensure that the boat cannot sink even in the event of severe damage.

Technical specifications

Parameter Data
crew 1
length 8.55 m
span 4.68 m without ears, 5.89 m with ears
height 2.40 m (later 2.00 m)
Wing area 13 m 2
Wing extension 1.7
Takeoff mass 350 kg
Sewage velocity 62 km / h
Minimum speed (ground) 70 km / h
Top speed 140 km / h
Service ceiling Max. 800 m for test flights
Engine 1 × Nelson H 63-CP with 29 kW (40 PS) (pusher propeller)

Whereabouts

The only copy of the X-113 is currently on display in the School of Engineering of Ngee Ann Polytechnic in Singapore .

See also

Web links

source

  1. ↑ M. Ziegler: X-113Am, interview with Dr. Lippisch , Flug-Revue March 1972