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LIORE & OLIVIER LéO H-470

 


Technical Specifications
Type
Seaplane patrol and transport
Date first flight
Juillet 23, 1937
Wingspan
31,80 m
Lenght
21,72 m
Height
7,10 m 
Wing Area
135 m2 
Empty Weight
10500 Kg 
Max. Takeoff Weight
18900 Kg 
Cruising Speed
296 km/h 
Maximum Speed
340 km/h
Climbing Speed
 
Service ceilling
7000m 
Range
3250 kms
Crew
5 Men
Motorization
4 Engine Hispano-Suiza 12Y34 liquid-cooled of 860ch each
Armament
4 machine-gun Darne of 7.5mm
600 Kgs of bombs

 


Production

6 LeO H470 and derivates have been built since the date of the first flight. They are divided into :

  • 1 Lioré & Olivier LéO H47
  • 5 Lioré & Olivier LéO H470

To date, out of the 6 aircrafts manufactured, 5 are listed in the list below :


Historical

In 1934, the Ministry of Air issues a specification for the realization of a plane capable of flying over the South Atlantic, connecting Dakar to Natal in Brazil. The demand was a cruising speed of 250 km / h at 2/3 of the engine power and the aircraft had to be able to carry 1000 kg of load with a range of 3000 kms.

Many manufacturers are responding to the program, and the Lioré & Olivier Company receives, on October 10, 1935, an order for the supply of a prototype: the LéO H47.

The design of the aircraft is led by Mrs Mercier and Benz who were responsible for the wings and the fuselage respectively. The company Lioré & Olivier has a wind tunnel, which explains the very elegant and successful design of the prototype. This one, manufactured in the Argenteuil plant, is delivered in two parts to Antibes where the final assembly is made. The aircraft made its first flight on July 25, 1936.

The Leo H.47 is of all-metal construction. It is powered by four Hispano-Suiza 12Ydrsl / Yfrsl grouped in pairs. The different tests are going well. The aircraft greatly exceeds the technical requirements of the program. It flies at 300 km / h at 3/4 of power, and at 361 km / h at maximum power. It has an autonomy of 4000 kms. Air France ordered, in March 1938, five standard aircraft, under the designation of Leo H470. The Navy is also interested in the aircraft, which could become an excellent Naval reconnaissance aircraft.

But, on May 19, 1937, when the Leo H47 was soon to be delivered to Air France, the ptrototype suffered a serious accident. Following a structural weakness, the plane sinks to the landing causing the 5 crewmen: there will be no survivors.

This accident does not question the order of Air France for 5 aircrafts. The company Lioré & Olivier, integrated into the SNCASE since the nationalizations, thus began the manufacture of the aircrafts in his factory of Vitrol. The serial version differ slightly from the prototype. Following the accident of the latter, the fuselage is reinforced, and the design of the mats connecting the wing to the fuselage is modified. The design of the drift is changed and the fuel capacity is increased. Under the engine nacelles, we see a device to increase the engine thrust (see photo below)

The first flight of the series aircraft took place July 23, 1937 in Vitrol, and after some internal tests, it is sent to Saint-Raphael for official tests. Air France crews have had time to fly a bit with the LéO H470, but none of the 5 LeO H470s will be delivered to Air France ... At the outbreak of hostilities, the Navy commandeers the 5 machines that are modified in Saint-Raphael for their new mission of distant reconnaissance. The fuselage is extended in its front part to receive the glazed position of the observer / navigator. It receives a defensive armament: 4 machine guns of 7.5mm and offensive with 4 lances bombs for a maximum of 600kgs of bombs.

The E11 Squadron, based on the Berre pond, received two aircrafts on December 4, 1939, followed four days later by a new H470. But this one will be quickly destroyed, when, on December 10, his pilot puts it by mistake on Lake Urbino (Corsica), not deep enough ... The last two LéO H470, will be taken care of on February 15, 1940. before that the Squadron E11 leaves the pond of Berre for the Lake of Biscarosse. Back on the pond of Berre from 24 April 1940, the squadron E11 will participate until the Armistice, with patrols in Mediterranean sea.

After the Armistice, the LéO H470s are used as transport planes, freight and passengers, on links between the metropolis and Tunisia. On August 10, one of the H470s will be shot down by the Italians near Sardinia. On August 1, 1944, Squadron E11 is renamed 11E, but the unit is disbanded as of August 15. The three surviving H.470s are transferred to the E9 Squadron based on the Berre Pond. In June 1941, they joined Dakar, to participate, as aircraft "petroleum", with tests of refueling at sea, seaplanes torpedo-boats Laté 298 of Escadrille 6T.

After the Allies landed in North Africa in November 1942, under the colors of Free France, the LéO H470s will be used to cover allied convoys leaving Dakar. But the invasion of the free zone by the Germans will ban the delivery of spare parts, and the Leo H470 are quickly put out of service. The last Leo H470 will be reformed in August 1943.


Versions

LéO H47

The Leo H47 was designed to respond to Air France's desire for a plane capable of making its link from Dakar to Natal in Brazil, over the South Atlantic. The aircraft, elegant, has a closed cockpit. It made its first flight on July 25, 1936. On May 19, 1937, when it was to be delivered to Air France, the Leo H47 suffered an accident due to structural weakness and sank. There will be 5 victims

LéO H470
Reinforced version ordered 5 copies by Air France despite the accident of the Leo H47. The Leo H470 has a reinforced fuselage, mats connecting the wing and hull of a different design and a modified drift. The fuselage is also lengthened, and the fuel capacity increased. A device installed under the engine nacelles can increase the thrust of the latter. First flight July 23, 1937
Required by the Navy, it will undergo modifications to turn it into a seaplane patrol. The nose of the plane receives the glazed position of the Navigator / Observer. It receives a defensive armament: 4 machine guns of 7.5mm and offensive with 4 lances bombs for a maximum of 600kgs of bombs.

 


Bibliography

1 )_ Larivière Editions - From December 1992 to March 1993
- Le Fana de L'Aviation No277 - 278 - 279- 280 : "The Lioré & Olivier H47 : War cut off his wings "

From Gérard BOUSQUET


Photos Album

 


Drawing 3 views

Links to Website
"French Air Force"