Hoverwing WIG craft technology

Second generation Wing in Ground Effect crafts by Hanno Fischer

Data sheets

 

X series WIG craft registered as Aircrafts (Millitary)

 X-113 (1971)

   After the successful operation of the X-112 in the U.S.A., (a proof- of concept aircraft, that was inherently stable both longitudinal and in longitudinal and in height within ground effect and in free flight), Dr. Alexander Lippisch returned to Germany and began a cooperation with Rhein Flugzeugbau GmbH (RFB).
   Together with Mr. Hanno Fischer, the Technical Director to RFB, he developed the X-113. The X-113 was designed to a Navy specification, and had to be operational both in Ground Effect and in free flight, where it was able to reach an altitude of 800 m. For that reason, it was built and registered as an aircraft.
   The Ground Effect mode was not utilised for economy, but for military operation below enemy radar detection.
   X-113 met all performance requirements, making the Lippisch design with its inverted delta wing and a high T-tail, the dominant design today.

Outline Specifications

 Dimensions:
 Length                 8.43 m
 Width                   5.89 m
 Height                  2.00 m
 Performance
 Range (no Reserves)        -   Nm 
 Cruise Speed                   95 km/h 
                                           55 knots 
 Efficient Cruise Height    0.175 m
 
 Weight
 Useful Load             91 kg
 Take-off Weight    360 kg 

 Cruise Power                         48 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


             

 


X-114 (1973)
   Success with the X-113 led to the requirement for a Navy ground effect craft to operate on the Baltic Sea. The minimum operational size for this craft, the X-114, was governed by its need to cope with the wave height in the Baltic.
   As with the X-113, this craft also was registered as an Aircraft.
In contrast to the trimaran layout of the X-113, the X-114 was designed as a catamaran, and provided valuable test data.

Outline Specifications

 Dimensions:
 Length                12.4 m
 Width                   8.7 m
 Height                 2.92 m
 Performance
 Range (no Reserves)        -   Nm 
 Cruise Speed                 130 km/h 
                                            70 knots 
 Efficient Cruise Height    0.175 m
 
 Weight
 
 Take-off Weight    1,600 kg 

 Cruise Power                       210 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


                  
 
X-114H (1974)
   Part of the Navy trials on the X-114 aimed to improve of take-off performance and seaworthiness.
   For the trials, the X-114 undercarriage was replaced with hydrofoils, and the craft designated X-114 H.
   The trials resulted in improved seaworthiness, but with increased take-off speed and take-off run distance.
   The trials gave valuable results, but the use of hydrofoils as take-off aid was discontinued.

Outline Specifications

 Dimensions:
 Length                12.4 m
 Width                   8.7 m
 Height                 2.92 m
 Performance
 Range (no Reserves)        -   Nm 
 Cruise Speed                 130 km/h 
                                            70 knots 
 Efficient Cruise Height    0.175 m
 
 Weight
 
 Take-off Weight    1,600 kg 

 Cruise Power                       210 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


                

               

Airfish series WIG craft registered as ships

Airfish - 1 (1987)

   Fischer Flugmechanik (FF) continued the developments ofRFB. In contrast to the earlier military objectives, the works of Fischer Flugmechanik aimed the concept at solving the transportation gap between fast and expensive aircraft and slow but cheap ships.
   Ground Effect craft have the economic potential to operate at speeds up to 10 times that of ships, while the costs can be significantly lower than those of aircraft.
   The first step of the development was to modify the successful Lippisch design so that the Airfish craft operated only in Ground Effect, and not in free flight.
   The objective of this “first generation” Ground Effect craft was to enable them to be designed, registered and licensed as boats, and NOT as aircraft.
   Airfish - 1 was the successful proof of this concept. Being registered as a boat, it cruised on 15 hp at 100 km/h over Lake Baldeney (Germany).

Outline Specifications

 Dimensions:
 Length                8.5 m
 Width                  9.5 m
 Height                 2.1 m
 Performance
 Range (no Reserves)        -   Nm 
 Cruise Speed                  95 km/h 
                                           55 knots 
 Efficient Cruise Height    0.1 m
 
 Weight
 
 Take-off Weight    320 kg 

 Cruise Power                       35 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m



Airfish - 2 (1988)
   Airfish - 1 paved the way for the Airfish concept towards marine registration. One of the disadvantages of the craft was the wingspan, particularly when handling the craft in marinas. In order to berth at docks or jetties the wing span had to be reduced significantly before a marketable craft could be achieved.
   With this aim, a set of new wings reduced span was fitted to the Airfish - 1 fuselage, resulting in a very different craft called Airfish - 2. Further improvements on the wing structure, the hydrodynamic design and a new engine increased the wing loading significantly.
   After successful testing, this knowledge was transferred to the next Airfish design, which was the first to be made to a market specification.

Outline Specifications

 Dimensions:
 Length                8.5 m
 Width                  6.8 m
 Height                 2.1 m
 Performance
 Range (no Reserves)        -   Nm 
 Cruise Speed                120 km/h 
                                           65 knots 
 Efficient Cruise Height    0.1 m
 
 Weight
 
 Take-off Weight    580 kg 

 Cruise Power                       70 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m



Airfish - 3 
(1990)
   Airfish - 3 was designed to a market specification for a recreational Ground Effect craft of Flarecraft Corp (USA). It was built at RFB under the design responsibility of Fischer Flugmechanik
   After successful maiden flight in 1988, the Airfish - 3 continued demonstrations in the Netherlands and in the Miami bay with its inter- coastal waterways, with permit from the US Coast Guard.
   Airfish - 3 was powered by a BMW 2-cylinder motorcycle engine.
   For easier handling, the aerodynamic control surfaces were all connected to one control wheel in the cockpit, similar to that of a boat. This allowed the craft to bank automatically and so give smooth, co-ordinated turns of small radius.
   During cruise, the craft was able to jump up for a short time in order to avoid obstacles. By leaving the Ground Effect during the jump the aerodynamic drag increases, which reduces speed andmakes the craft return into ground effect automatically.
   Jumps up to half wing span were experienced.

Outline Specifications

 Dimensions:
 Length                9.9 m
 Width                  7.5 m
 Height                 2.6 m
 Performance
 Range (no Reserves)    410 Nm 
 Cruise Speed                120 km/h 
                                           65 knots 
 Efficient Cruise Height    0.1 m
 
 Weight
 Payload                 220 kg
 Take-off Weight    760 kg 

 Cruise Power                       75 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


                 


Airfish - 3 PA (1992)
   Airfish - 3
 made feasible the commercial use of Ground Effect Craft that would be designed and registered as boats.
   Aiming towards bigger craft it became obvious that above a certain size of craft, the hydrodynamic drag during take-off would be significantly higher, than the power required for cruise.
   In order to find a solution to this for future vessels, Fischer Flugmechanik modified the Airfish - 3 to a power augmented craft.
   The slipstream of two propellers at the bow, driven by small engines was directed below the wings to create an air cushion. This reduced the displacement of the craft as soon as these engines were running, and improved the take off of Airfish - 3.
   The power augmentation was discontinued because the Hoverwing Technology that was developed later offered a variety of improvements for the design of bigger WIG crafts.

Outline Specifications

 Dimensions:
 Length                9.9 m
 Width                  8.5 m
 Height                 2.6 m
 Performance
 Range (no Reserves)    410 Nm 
 Cruise Speed                120 km/h 
                                           65 knots 
 Efficient Cruise Height    0.1 m
 
 Weight
 Payload                 220 kg
 Take-off Weight    860 kg 

 Cruise Power                       125 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


                

Airfish - 8 (2001)
   Flightship 8 - (FS8) is the market name for the AFD developedAirfish - 8 (AF8) . The technical origin of Airfish - 8 are the earlier designed Airfish - 1Airfish - 2 and Airfish - 3 of the joint companyFischer Flugmechanik.
   FS8 has been completed in February 2001, and made its successful maiden flight on February 20th, 2001. Certification by Germanischer Lloyd: +100 A0 WIG – A , WH 0,5/1,5 EXP.
   FS8 has been developed for Flightship Ground Effect Pte, Cairns, Australia, who will produce and market the vessel under license of AFD.
   FS8 will operate as a high speed water taxi at the maledives, the barrier reef etc.

Outline Specifications

 Dimensions:
 Length               17.22 m
 Width                 15.16 m
 Height                  3.35 m
 Performance
 Range (no Reserves)    200 Nm 
 Cruise Speed                160 km/h 
                                           86 knots 
 Efficient Cruise Height  <=  1 m
 
 Weight
 Payload                 220 kg
 Take-off Weight    860 kg 

 Cruise Power                       330 hp
 Max Wave Height Take-off      - m
 Max Wave Height Cruise         - m


      

      

      

      

      
 
Hoverwing series WIG craft registered as ships

Hoverwing 2VT (1997)
   To verify the results of an experimental and theoreticalHoverwing 80, 80 passenger ferry design, the 2 seated test craftHoverwing 2VT was built and successfully tested. This craft is 1/3rd scale model of the projected Hoverwing 80.
   Its objective was to prove the validity of the predicted performance and characteristics as a basis for further developments.
Hoverwing 2VT went through a series of intensive sea trials and was operated on inland waters in Germany, the Baltic Sea and the Markermeer in the Netherlands.
   The knowledge base gained from trouble free operation of the Hoverwing 2VT over 3,000 km of trials underpins the design of future Hoverwing vessels.

Outline Specifications

 Dimensions:
 Length                10.3 m
 Width                    9.5 m
 Height                   2.5 m
 Performance
 Range (no Reserves)        -  Nm 
 Cruise Speed                135 km/h 
                                           73 knots 
 Efficient Cruise Height  <=  1 m
 
 Weight
 Payload                 230 kg
 Take-off Weight    1,160 kg 

 Cruise Power                       90 hp
 Max Wave Height Take-off     0.5 m
 Max Wave Height Cruise        1.5 m