Military

Crashed on takeoff from Chabua AFB. At least one crew was killed.

The aircraft left RAF Lyneham at 2230LT on a transit flight to Gibraltar but failed to arrive. No trace of the aircraft nor the crew was found and it is believed it crashed into the Atlantic Ocean or the Bay of Biscay.
Crew (512th Squadron):
W/Cdr Patrick E. Hadow,
F/O R. L. Hammill,
LAC Charles W. Summers,
W/O Cyril Frederick Dean Steel.

Shortly after take off from RAF Newquay-St Mawgan, the aircraft impacted a hill and was destroyed. All four crew members were killed.
Source:
http://aviation-safety.net/database/record.php?id=19431223-0

The aircraft left Dobodura-North Borio Airfield at 1451LT but failed to arrive in Port Moresby-Wards Airport. SAR operations were conducted and the wreckage was spotted on January 12, 1944, on the slope of Mt Victoria located in the Owen Stanley Range. Unfortunately, it was impossible for a rescue team to reach the site due to the difficult terrain.
Crew:
S/Sgt Benton D. Campbell,
1st Lt Gale J. Chase,
S/Sgt Joseph C. Draper,
1st Lt Frank C. Gecan,
Cpl Joseph J. Ransdell,
Cpl Everett F. Rogers.

The four engine aircraft departed by night on a transatlantic flight to Europe. After a takeoff roll of 7,000 feet, the airplane rotated but encountered difficulties to gain height when it struck Australian pines and crashed in a huge explosion just past the runway end. Twelve crew members were killed while two others were injured. The aircraft was destroyed.
Crew:
Samuel Gerald Dean, pilot, †
Edward Joseph Wolbers, copilot, †
Radamés E. Cáceres, navigator, †
Douglas Laurent Dauphin, bombardier, †
Bert Garland Sauls Jr., master gunner, †
Kenneth N. Markle, radio operator, †
Louis Karp, artillery gunner, †
James Henry “Jim” Henderson, artillery gunner, †
Douglas Vincent Schmoker, artillery gunner, †
Howard George Sewell, turret gunner.
Passengers:
George M. “Pud” Durrett, †
Robert H. Watson, †
Harold Edwin Richards, †
James Dixon “Big Jim” Fore. †

Crashed in unknown circumstances on the slope of Mt Brandon, Munster. All six Polish crew members were killed.
Crew:
Sgt Klemens Adamowicz,
Sgt/C Stanislaw Czerniawski,
Sgt/C Pawel Kowalewicz,
Sgt/C Naftali Hirsz Pawel Kuflik,
Pvt Kazimierz Lugowski,
Cpl Wincenty Pietrzak.

The aircraft left Townsville-Garbutt Field at 0710LT for a flight to Brisbane with an intermediate stop in Rockhampton, on behalf of the Royal Australian Air Force (RAAF). En route, the aircraft exploded, dove into the ground and disintegrated in a wooded area located 48 km north of Rockhampton, near the road to Rossmoya. All 31 occupants were killed. Worst accident involving a USAF C-47 up to date.
Crew (22nd TCS):
2nd Lt William Randell Crecelius, pilot,
2nd Lt John R. Powell, copilot,
T/Sgt John L. Shupe, flight engineer,
Sgt Robert S. Fazio, radio operator.
Passengers:
Cpt Orlen N. Loverin,
1st Lt George K. Snyder,
2nd Lt William B. Graham,
T/Sgt Carlos M. Bane,
Cpt Robert J. Simons,
Maj Hoyt A. Ross,
Lt Rebecca Williams,
3rd Cl Jack Hayman Staggs,
C. G. M. Carline,
Lt W. M. Samuelson,
Lt Thomas Smith,
Lt Ernestine Korranda,
W/O Herbert R. Johnson,
Lt Harry Gillies,
Pvt Herbert J. Mathias,
Sgt Charles Dolan,
Harold George Dick,
William Bramwell Tibbs,
Cpl William Barry Sleep,
Cpl Thomas William Shard,
Pvt Benjamin Rasmussen,
Cpt John Hugho Weir,
Cpt Alexander William Robert Geddes,
Lt Nigel James Bruce MacDonald,
LAC Donald Cantrol Cameron,
LAC Raymond Kingsley Oster,
Cpt Crawford Derek Mollison.
Source: http://www.ozatwar.com/ozcrashes/qld56.htm

The seaplane left RAF Pembroke Dock at 2345LT on December 18 on a routine flight to Gibraltar with 19 crew members on board (two complete crews and reinforcements to the squadron as passengers). While cruising by night some 30 miles off the Saint-Vincent Cape located on the southwest coast of Portugal, the crew was able to send a distress IFF signal that was received by the crew of a second Short Sunderland which was following DW106. Despite intense SAR operations, no trace of the aircraft nor the crew was found.
Crew (270th Squadron):
F/O Vernon Maurice Sparkes,
F/Sgt Charles Albert Mark Barber,
F/Lt John Eric Wood,
F/Sgt Frederic Raymond Brown,
F/O Edward James Jay,
F/Sgt Francis Mcphee,
F/O Reginald Robert Terance Crump,
F/Sgt Eric Piggott Botting,
P/O Neil Procter Chapman,
F/O Norman Edmond Hanna,
Sgt Stanley Kidd,
F/O Raymond John Elderfield,
Sgt William Henry Cryer,
Sgt William Peter Houston,
Sgt Henry Leonard Thompson,
Sgt Maurice Robert Hunt,
Sgt Edmund Albert Hooker,
Sgt Samuel Hughes,
F/Sgt Leslie Robinson.
Source:
http://www.landinportugal.org/air_pages/a01_copy(133).htm

The crew was on his way to RAF Dunkeswell, Devon, following a flight from the US. While flying over Manchester, the crew was informed that RAF Dunkeswell was closed to traffic due to unfavorable weather conditions. The crew tried several times to locate the airport but without success. Eventually, all 10 occupants decided to abandon the aircraft and bailed out. Out of control, the aircraft crashed on peat moorland named Broken Bround and located some ten miles East of Manchester, near Mossley. While the aircraft was destroyed, all ten occupants were unhurt.

While cruising in low visibility, the aircraft hit the slope of Mt Cnoc na Peiste (988 metres high) located southwest of Killarney. All 5 occupants were killed.
Crew:
2nd Lt Frederick V. Brossard,
2nd Lt Lawrence E. Goodin,
S/Sgt Wesley T. Holstlaw,
2nd Lt John L. Scharf,
Sgt Arthur A. Schwartz .