Delta Air Freighters: 1947-1973

In the immediate postwar years there were forecasts for an explosion in air freight volumes, which never really came about. Nevertheless several of the US trunk airlines dabbled in cargo only operations to some degree, however few acquired bespoke cargo aircraft. Most were happy to convert their existing piston props or acquire freighter versions of aircraft they already operated. Delta was an exception and twice acquired new freighter types to satisfy demand.

During World War 2 Delta gained experience of freight hauling by flying for the Military Transport Division of the USAAF and following the end of hostilities a pair of ex-USAAF Douglas C-47s (NC86553 and NC51359) were acquired for cargo only operations. They linked Atlanta with Chicago via Cincinnati. A third aircraft (N57539) was added during 1949 but though the C-47s served well by the mid-50s they weren't really competitive.

The Curtiss C-46 Commando had failed as a passenger aircraft but after 'teething' issues (ahem - inflight explosions!!) had been resolved it proved a capacious freighter. Delta acquired five second-hand aircraft and put them into service from October 1957. All five had originally been flown by Civil Air Transport of Taiwan. A huge fleet had been supplied to the Nationalist Chinese during and after the war. Delta's cargo business had expanded by 724% since 1947 and the C-46s allowed for an increase in cargo capacity by 600%. Delta advertised that the Commando had extra large doors "large enough to load a Cadillac automobile without scratching the paint job,"

Delta's C-46s were registered N9873-74F and N9883-85F. The C-46s continued to serve into the mid-1960s even after the new jet fleets began to enter service with their huge belly freight capacity. One aircraft, N9885F, was written off at Baton Rouge on November 24, 1964. She had been diverted from a fogbound New Orleans but conditions at Baton Rouge were also poor. On approach the pilot failed to go around and landed 2500 feet past the runway threshold. The aircraft failed to stop and hydroplaned off the runway end. Both pilots survived.

Despite the increase in freight capacity of the new passenger jets Delta remained firmly committed to pure freighters and on September 15, 1966 it became one of the first commercial operators of the civilianised version of the Hercules - the Lockheed L-100-10. Delta advertised the Herc heavily as can be seen in this shot from a multi-page promotional piece:

Delta advertised the aircraft's capacity, dependability, speed and flexibility. It could fly between Chicago and Atlanta in less than 2.5 hours and Dallas to Los Angeles in 4.5. Delta also used what at the time it advertised as a unique system of truck-bed height transporters allowing easy loading of the Hercs via a roller bed surface. Within two years of service entry Delta returned its trio of aircraft (N9258R, N9259R and N9268R) to Lockheed where they were stretched into L100-20s nearly 3 metres longer than the L-100-10s. Several other Hercules were leased during the period that the airline's own aircraft were upgraded. A fourth aircraft, N9262R, was also leased briefly in June 1970. The first three pictures below show the original L-100-10:

Above: After stretching the L-100-20 in Delta colours

The Hercules flew a network of routes from Atlanta to destinations like Chicago, Detroit, New York, Charlotte, Miami, Orlando, New Orleans, Dallas with the latter route extending to Los Angeles and San Francisco. The L-100-10s flew with external fuel tanks under the wings but the stretched L-100-20s disposed of these. By the early 1970s the writing was on the wall for Delta's freighter fleet. The advent of widebody 747s and DC-10s in the Delta fleet added a huge increase in belly freight capacity, which eliminated the need for specialist cargo aircraft. The Hercules was withdrawn from the fleet on September 1, 1973 bringing to an end Delta Air Freighter service. Delta's three Hercs went on to separate careers initially with Saturn Airways, Alaska International and Pacific Western respectively.

References

1966. Delta Museum - Lockheed L-100 Brochure
Davies. R.E.G. 1990. Delta: An Airlines and its Aircraft
Delta Museum - C-46