Latécoère 631 | Bureau of Aircraft Accidents Archives

The aircraft was performing a flight from Lake Léré to Douala, carrying eight passengers, a crew of eight and a load of cotton bales. While cruising in a tropical storm, the aircraft encountered thunderstorm activity and severe turbulences when a wing failed. Out of control, the airplane went into a dive and crashed 60 km north of Banyo. The airplane was destroyed and all 16 occupants were killed. This was the last mission for this aircraft and its crew who must fly back to Biscarosse (France) to conduct tests and maintenance. This was also the last Latécoère 631 in service.

Probable cause:

Structural failure of a wing in flight caused by turbulences that exceeded its design.

Crash of a Latécoère 631 off Le Cap Ferret: 12 killed

Date & Time: Mar 28, 1950 at 1730 LT

Type of aircraft:

Latécoère 631

Operator:

Société d'Exploitation du Matériel Aéronautique Français (SEMAF)

Registration:

F-WANU

Flight Phase:

Flight

Flight Type:

Test

Survivors:

Site:

Lake, Sea, Ocean, River

Schedule:

Biscarosse - Biscarosse

MSN:

YOM:

Location:

Country:

Region:

Crew on board:

Crew fatalities:

Pax on board:

Pax fatalities:

Other fatalities:

Total fatalities:

Aircraft flight hours:

1001

Circumstances:

The crew (engineers and pilots) were engaged in a test flight on this third prototype consisting of controls in flight following severe vibrations on the engines. While cruising at an altitude of 1,200 meters, the six engines seaplane lost a part on the right wing, went out of control and crashed into the sea about one km northwest of Le Cap Ferret. The crew of a trawler and a French Marine boat found some debris floating on water but unfortunately, all 12 occupants were killed.
Crew:
Robert Boissard, Chief Pilot,
Mr. Dumonteil, mechanic,
Kléber Coulé, mechanic,
Henri Faugère, mechanic,
Alexandre Lepêcheur, radio operator,
Mr. Renaud, technical director,
Mr. Remaury, technician,
Adj Grezel,
Mr. Malpot, engineer,
Mr. Bouchery, techincal director,
Mr. Martin, engineer,
Mr. Brolin, engineer.

Probable cause:

The inquiry came to the conclusion that the probable cause of the accident was a fatigue failure of the aileron control couplings resulting from the simultaneous occurrence of several vibratory phenomena: the cruising speed of the propeller with a 7/16 reducing gear in resonance with the critical vibratory frequencies of the wing and the aileron (excitation amplified by the propeller cuffs); and the occurrence of extreme aileron flutter, aerodynamically induced as a result of failure of the linkage between the aileron and the slat. In such conditions, it was impossible for the crew to detect these phenomena before their results became irreparable.

Final Report:

Crash of a Latécoère 631 into the Atlantic Ocean: 52 killed

Date & Time: Aug 1, 1948 at 2355 LT

Type of aircraft:

Latécoère 631

Operator:

Registration:

F-BDRC

Flight Phase:

Flight

Flight Type:

Scheduled Revenue Flight

Survivors:

Site:

Lake, Sea, Ocean, River

Schedule:

Fort-de-France – Port-Etienne – Paris

MSN:

YOM:

1947

Flight number:

AF072

Location:

Country:

Region:

Crew on board:

Crew fatalities:

Pax on board:

Pax fatalities:

Other fatalities:

Total fatalities:

Aircraft flight hours:

185

Circumstances:

The crew was performing a flight from Fort-de-France, Martinique, to Paris, with an intermediate stop in Port-Etienne, Mauritania. While cruising by night over the Atlantic Ocean, about 1,920 km from Port-Etienne (now Nouadhibou), the aircraft crashed into the ocean in unknown circumstances at 2355LT. No message was sent by the crew. SAR operations were jointly conducted by several countries and few debris were found by the crew of USS Campbell three days later, on August 4. Unfortunately, none of the 52 occupants survived the crash of this six-engine aircraft christened 'Henri Guillaumet'.
Crew:
Corentin Kersual, pilot,
Jean Goutay, copilot,
Henri Gloux, radio navigator,
Gontran Ronat, radio navigator,
Henri Cabanes, navigator,
Gaston Le Morvan, mechanic,
Jean Coustaline, mechanic,
Alfred Jaggi, mechanic,
Mr. Arbelot, mechanic,
Mr. Sgourdeos, steward,
Mr. Meunier, steward.

Probable cause:

Due to lack of concrete evidence, it was not possible to determine the exact cause of this tragedy. However, experts did not exclude the hypothesis of a serious technical issue sustained during flight.

Crash of a Latécoère 631 off Saint-Marcouf Islands: 19 killed

Date & Time: Feb 21, 1948 at 1400 LT

Type of aircraft:

Latécoère 631

Operator:

Registration:

F-BDRD

Flight Phase:

Flight

Flight Type:

Positioning

Survivors:

Site:

Lake, Sea, Ocean, River

Schedule:

Le Havre – Biscarosse

MSN:

YOM:

1948

Location:

Saint-Marcouf Islands

Manche

Country:

France

Region:

Europe

Crew on board:

Crew fatalities:

Pax on board:

Pax fatalities:

Other fatalities:

Total fatalities:

Circumstances:

Few minutes after takeoff from Le Havre, while flying over the Bay of Seine, the crew encountered poor weather conditions with snow falls. The seaplane went out of control and crashed into the sea off the Saint-Marcouf Islands, between Le Havre and Cherbourg. The aircraft was lost and all 19 occupants, pilots and engineers of the manufacturer, were killed.