The Consolidated C-109 was a fuel tanker produced from the B-24 Liberator and mainly used on the 'hump' between India and China.
The conversion was designed by Consolidated, but Ford carried out the actual work. The first example, the XC-109, was converted from a B-24E in 1943. This was followed by 208 production aircraft, based on the B-24J/B-24L.
The first stage in the conversion was to strip all unnecessary weight from the basic B-24. This included the turrets, armour, bomb shackles, bombing instruments and associating wiring, flooring, upholstering and curtains. This reduced the empty weight, without the C-109 additions, fuel and oil, to 32,500lb. Once the fuel tanks and other changes had been made the weight rose to 35,500lb without fuel and oil.
The C-109 carried eight extra fuel tanks.
No.1 was a 100 gallon tank was carried in the nose, in the bombardier's compartment. This was installed in order to balance the aircraft, which was tail heavy when all of the other tanks were full.
No.2 and No.3 were 400 gallon tanks carried side by side in the forward part of the bomb bay.
No.4 and No.5 were 425 gallon tanks carried side by side in the aft part of the bomb bay.
An extra cargo area was installed above the aft part of the bomb bay, behind the wing. This replaced the command deck of the B-24, and meant that the radio equipment had to be moved forward to the flight deck.
No.6 and No.8 were 175 gallon tanks carried side by side at the back of the cargo area.
No.7 was a 120 gallon tank carried across the front part of the cargo area.
This gave a total theoretical capacity of 2,220 gallons of fuel on top of the existing fuel tanks, but the actual limit was 2,036 gallons.
500lb of ballast had to be carried in the tail when the cargo tanks were empty.
The C-109 could only be used as a transport aircraft, and not for air-to-air refuelling.
A CO2 purging system was installed to make sure that the fuel cargo tanks could be completely emptied when not in use. This was done to remove the risk of fire posed by fumes in a poorly emptied tank.
The aircraft had to be handled carefully when fully loaded. After a series of crashes at take-off the fuel load was often reduced to 1,200 gallons, to avoid further disasters.
Another program saw a number of B-24Js modified to C-109 standard, but these kept the guns and the B-24 designation
A total of 208 C-109s were produced. Ford converted the bulk of them, 199 aircraft. Martin converted another nine. These had flexible fuel tanks, an automatic Auxiliary Power Unit shut-off and a different fuel system.
The majority of C-109s were used to fly fuel across the 'hump' between India and China as part of the vast effort to support B-29 operations from bases in China. A small number saw limited use with IX Troop Transport Command and the ATC in Europe.
Length: 66ft 4in
Gross Weight: 65,000lb
Cruising Speed: 300mph
Payload: 2,036 gallons of fuel
Consolidated C-109 Gallery