Amazing Flying Boat - Future of Sea Travel ... well, not really.

okikuma

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Amazing Flying Boat - Future of Sea Travel ... well, not really.

The Ground Effect Vehicles or Wing-In-Ground effect (WIG) as presently called is not a new idea. The design was first conceived in the early 1960s by Dr. Alexander Lippisch, a German aerospace engineer that was brought to the United States under Operation Paperclip. Dr, Lippisch was a pioneer in tailless aircraft, delta wing, and ground effect aircraft designs. He is most noted in designing the rocket powered Messerschmitt 163 Komet.

While working for the Aeronautical Division of the Collins Radio Company, Dr. Lippisch developed interest in designing a ground effect vehicle that would "fly" low level over water. In 1963, the Collins X-112 Airfoil Boat was built as a "proof-of-concept" aircraft to test his theory.

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X-112 Airfoil Boat

Powered by a 25 hp horizontally opposed, twin cylinder, air cooled engine, the X-112 Airfoil Boat flew very well up to 67 knots in speed, proving the concept was valid.

After resigning from Collins Radio Company because of a short illness with cancer, Dr. Lippisch formed his own company, Lippisch Research Corporation and continued his research in ground effect. In the 1970s, with interest and funding from the government of West Germany, Dr. Lippisch designed and tested the RFB X-113, and RFB X-114. No further testing or development was attempted after these two designs by Dr. Lippisch.

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X-113
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X-114

During the same time period as Dr. Lippisch, a Soviet aerospace engineer, Rostislav Alexeyev designed a version of a ground effect vehicle (Ekranoplan in Russian) for the Soviet Navy on a grand scale. The KM (Korabl Maket - "Ship Prototype" in Russian) was nicknamed the Caspian Sea Monster by CIA analysis when it was first viewed by reconnaissance satellite while under tow on the Caspian Sea. With the length of 302 ft long, wing span of 123 ft, takeoff weight of 494 tons, cruise speed of 270 knots just feet above the water, and a range of 810 nautical miles, the KM Ekranoplan was the largest aircraft in the world until 1988. The Soviet Navy was interested in the KM because it was able to "fly" low over the water and to be considered undetectable by enemy ship radar. The KM was tested and flown from 1966 until it was lost in an accident in 1980.

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KM Ekranoplan - Caspian Sea Monster

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Size comparison with human figures

With lessons learned from testing the KM Caspian Sea Monster, the Lun-class MD-160 Ekranoplan, was developed and tested by the Soviet Navy in 1975. The MD-160 was able to carry six P-270 Moskit Antiship Missiles. The MD-160 remained operational service with the Soviet and then the Russian Navy until the late 1990s.

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Lun-class MD-160 Ekranoplan

On and off for the next 40 years, several other individuals and small companies have tried to resurrect Dr. Lippisch's ground effect vehicle design.

Interestingly enough in 2010, the Islamic Revolutionary Guard Corps of Iran has designed and place into operation a number of ground effect vehicles, the Bavar-2.

The Bavar-2 is designed for carrying-out asymmetric approaches to conventional naval surface forces, especially at night and within the confines of an area as restricted (and often congested) as the Persian Gulf. The Bavar-2 is believed to exhibit a small radar signature and is therefore difficult to pick-up and track, especially while lying passive/motionless, when set against a cluttered backdrop, while merely trolling (see photo) and/or at longer ranges. Its reduced cross-section is intended to allow the Bavar to remain undetected while carrying out reconnaissance/patrol/attack missions.

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Bavar-2

As I was looking over the various photos of the Bavar-2, I noticed it is powered by a Subaru EJ25 automotive with an electrically controllable pitch Magnum IVO prop. In this configuration, it is very safe to surmise that this engine conversion is providing at least 150 hp if not more. Enough power to climb out of ground effect and fly as a conventional aircraft as viewed in one video. Unfortunately, the inverted reverse delta configuration of the wing has a very low aspect ratio with a very poor glide characteristics, not to mention the the poor stability with the anhedral. Not very safe when flying out of ground effect.
What brought on this lengthy and detailed e-mail are the following videos of the Wigetworks AirFish-8 ground effect vehicle that I came across and started to watch. Wigetworks is a small company operating out of Singapore. They originally developed the two place AirFish-3, powered by a BMW horizontally opposed, air cooled, motorcycle engine. From the AirFish-3, the AirFish-8 was designed.

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AirFish-3

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AirFish-8

Although ground effect vehicles appear similar to regular aircraft, and have related technical characteristics, they do not fit within the category of aircraft, seaplanes, hovercraft, nor hydrofoils. The International Maritime Organization classifies these vehicles as maritime ships and are registered as such. Therefore, "fly" such a craft, one does not need to be a licensed pilot. One only needs the required boating credentials as required by their host state or country.

In reality, a ground effect vehicle is a limited craft. With the Dr. Lippisch inverted reverse delta wing design, the highest altitude to remain within effective ground effect is 50% of the total wing span. This is why in all of the videos, one will see the "flights" are over only calm seas. Not very operational when limited to fair days, light winds and small swells.

Never-the-less, if presented with the opportunity, I'd definitely would "fly" a ground effect vehicle for the thrill.

Wayne

Amazing Flying Boat - Future of Sea Travel - AirFish-8



AirFish-3


What happened to the Ekranoplan? - The Caspian Sea Monster


The theory on how a Ground Effect Vehicle "flies."


Delta 2 Lippisch-type ground effect glider

https://www.youtube.com/watch?v=NvxzGERqDXI

Iran unveils 'Bavar 2' stealth flying boat with machine gun and camera - 28 Sept. 2010

https://www.youtube.com/watch?v=qTIoezhRS3g
 

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Very interesting Wayne. They have certainly been an area of transport that seemed to hold promise but that somehow never advanced much beyond the experimental stages, though having said this the Russian MD-160 seems to have remained in service for quite a period of time.

It seems that limitations in longitudinal stability may have prevented its further development...for the time being.


In some ways this to me has been echoed by the Fairy Rotodyne, a concept that held much promise but ended possibly before it full potential could be realised...but in light of advances made in materials, and technology remains a tantalising promise of unexplored potential.

And as a complete afterthought... the fighter that should have been, and whose concept remains valid today, the F-20 Tigershark.
Closed down due to the loss of two due to G-loc, but was way ahead of its time.
 
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