François Denhaut

François Denhaut
Residence France
Occupation Pilot, inventor, aviator

François Denhaut was a French aviator notable for designing, constructing and flying the first flying boat, or seaplane with a hull, in 1912.[1] He was born on 4 October 1877 at Champagnat, Creuse and died at Bellegarde-en-Marche in 1952. He was the chief pilot of Pierre Levasseur's flying school.[1][2]

Contents

1911 Model

The endeavour to build a flying boat began following Denham's construction of a seaplane with a hull in 1911. This design marked one of the first large steps forward in marine aviation, and constituted a pioneering leap in this area. The hull was triangular in shape, with the apex at the top. To achieve successful hydrodynamic lift, the hull was fitted with styled lift-off plates. It had a 50 hp (37 kW) engine that was of a unique make driving a pusher propeller, and which was placed up high, behind the pilot seat. To allow for maneuvering on the ground, an undercarriage was fitted, with two wheels attached.[3] Denhaut took particular advantage of this aspect of the design by taking off from the ground when he made the initial tests. This project was financed by Jacques Donnet,[4] and the craft was later named after him.[1]

The first proper test of the craft took place on 12 March 1912. Denhaut took off and flew over the River Seine. However, when preparing to land, the aircraft didn't straighten out properly, and the plates were submerged under the water while the it was still flying. This caused the aircraft to flip over; Denhaut managed to escape from the waterlogged cockpit, and took refuge on the bottom of the upturned hull. The craft was towed back to shore.[5]

1912 modifications

Denhaut, with the advice of Robert Duhamel, decided to rebuild the aircraft, making the necessary modifications to the first design model. He changed the hull to be rectangular in shape, because it had previously been very slender, and had tended to dip into the water. He also made slight modifications to the position of the undercarriage.

He tested the modified design on a stretch of water behind Port Aviation, where he had first tested the older model. After this test, the wheels were, temporarily, replaced with water floats.

On 13 April 1912, slightly over a month since the initial test of the first design, Denhaut's craft flew from Juvisy airfield, and landed on muddy ground close to the River Seine. The aircraft was pushed into the water where it took off and alighted seven or eight times. Denhaut then returned to the bank of the River Seine. Denhaut's second model had succeeded in becoming the world's first flying boat. Many later designs for flying boats can be seen to be very clearly based upon Denhaut's design.[1]

Specifications
Wingspan 10.86 m
Length 8.40 m
Wing area 21.80 meters
Curb weight 436 kg
Total weight 650 kg
Max. speed 97 km/h
Max. on board 1 pilot, 1 passenger

Notes

  1. ^ a b c d Nicolaou, p.17
  2. ^ Parrochia, p.130
  3. ^ Parrochia p.131
  4. ^ Cahisa, p.227
  5. ^ Noetinger, p.323

References

  • Nicolaou, Stéphane (1998). Flying Boats & Seaplanes: A History from 1905. Zenith Imprint. ISBN 0760306214. 
  • Parrochia, Daniel (2003). L'homme volant: philosophie de l'aéronautique et des techniques de navigation. Editions Champ Vallon. ISBN 2876733676. 
  • Noetinger, Jacques (1989). Rencontres des hommes et des ailes au Musée de l'air et de l'espace. Editions France Empire. 
  • Cahisa, Raymond (1950). L'aviation d'Ader et des temps héroïques. Michel.