What was the Constellation's "Speedpack"?

The L-749 was the Constellation version that enabled nonstop flights between New York and Paris, thanks to additional integral tanks in the outer wings that raised its range to 6,400 km; before that, aircraft had to refuel at Gander, Newfoundland, before crossing the Atlantic. 50 were built, and from summer 1948 came the L-749A, considered the pinnacle of the series, with 60 aircraft. But these versions had a limitation: their holds weren't big enough to make use of all the maximum payload the aircraft could lift.

Lockheed's answer was the Speedpack, an external cargo container with capacity for 2,000 kg. It was attached under the central part of the fuselage with quick-release fasteners, so airlines could fit it only when the flight required it and remove it afterward. It was, in effect, an additional hold the aircraft could carry or leave on the ground depending on demand.

The accessory was seen with the model's major operators. Photographs from the era show, for example, a TWA L-749A at London Heathrow Airport in 1954 with the Speedpack under the fuselage, and an Air France Constellation fitted with one taking off from Frankfurt around 1954 or 1955. It was a simple way to get more out of the first-generation Constellations without modifying their structure, at a time when airlines were looking to make every transatlantic flight more profitable. In total, Lockheed built 233 aircraft of the Constellation's short-fuselage versions, including the 34 military C-69, C-121, and PO-1 aircraft.