During WWII the Army called for an “air transportable earthmover” and LeTourneau took up the challenge.
THE FIRST LETOURNEAU Model D Tournapull with Model Q Carryall was rolled out in 1942.
It was then sent to the US Army’s proving ground at Fort Belvoir, Virginia for trials, which were conducted by the Corps of Engineers. Following these tests, which proved that the little machine was capable of doing what the Army required, it was passed on to the Airborne Equipment Engineers for air drop suitability testing.
This extensive test regime, which lasted almost two years, meant that the machine didn’t actually go into production until mid 1944, by which time the island hopping campaign in the Pacific was in full swing.
The Model D & Q Carryall could be carried partially assembled in a Douglas C-47, Curtiss C-46, or Douglas C-54 transport aircraft and parachuted into where it was needed, or swallowed fully assembled and ready to be put straight into action inside a Waco CG-4A cargo glider.
LeTourneau engineers had incorporated only as much equipment as was necessary into the design of the Model D in order to keep the tare weight as low as possible, while still offering a valid and versatile earthmover. To this end they succeeded admirably.
From 1942 to when production ended in 1946, LeTourneau built over 600 of the little critters, not all of which were destined for the US Army.
Following the termination of WWII, the type continued in production.
LeTourneau marketed the non-military machines, (known as the Model D4 Tournapull), to small contractors, railway companies (an ideal roadbed maintenance tool), landscapers, small townships, coal distributors, counties, industries, paving contractors, gold miners and even cemeteries!
The operator’s controls were extremely basic – hand clutch, two steering levers, gearshift, accelerator pedal foot brakes (two) and PCU controls – that was it!
It was finally replaced in late 1946 by another Tournapull, also called the Model D which was a completely new design from the ground up.
There are quite a few survivors of the breed, most of which reside in the USA.
The Model D in detail
The Model D Tournapull was powered by a Continental Y112 four cylinder gasoline engine that put out 44 flywheel horsepower and was connected, via a single plate hand operated clutch, to a four speed manual transmission made by Borg-Warner. This was a very similar transmission to that which was then used widely in the Army’s Ford five-ton trucks, allowing for a good bit of parts commonality in the field.
Design of the steering system was the same as used on the larger Model Super C Tournapull only on a smaller scale and this consisted of a steering clutch and contracting band brake for each drive wheel. When going downhill with a load the machine had to be cross-steered just like a track type tractor or calamity would result.
These machines were not for the faint hearted!
The entire engine, transmission and final drive assembly was contained within a welded ‘tub’ for structural rigidity.
Attached to the rear of the final drive case was the cable control unit (PCU). In the case of the model D this was normally a model L, a three-drum affair that was operated by means of cone-type clutches just like other PCUs in the LeTourneau range.
LeTourneau cable controls were very rugged affairs and seldom required major overhaul, thus making them ideal for combat type situations where any kind of maintenance was obviously kept to a bare minimum.
The operator’s controls were extremely basic – hand clutch, two steering levers, gearshift, accelerator pedal foot brakes (two) and PCU controls – that was it!
A small panel on the back of the hood held a water temperature gauge, ammeter and a starter switch and that was the extent of the instrumentation.
On the machines that were fitted with headlights, a light switch would be added to this cluster.
For a machine initially designed for the military, the operator sat in a very exposed position on a very elementary, non-sprung seat. At least he had a good view of the world around him!
The Q Carryall
With a struck rating of two cubic yards and a heaped capacity of 2.3 cubic yards, the little Q Carryall was the ideal tool for filling in bomb craters.
It was entirely cable-controlled and had a very large spring in the pushbeam for helping to pull the tailgate back once it had ejected a load.
The Model D/Q Carryall combination could self-load without the need for a pusher as it had a very good power to weight ratio – 1 horsepower per 250lb (113kg) of weight.
LeTourneau wasted no time in designing extra attachments for use with the D Tournapull.
First up was a demountable tilt dozer, the Model AD, operated off the third drum of the PCU.
A unit equipped with the AD dozer was a very versatile tool as not only could it transport earth but maintain fills, create paths or push load other Ds if necessary.
There was also a Model D Tournatruck, a flat bed trailer with a five ton capacity for transporting goods as large as a fully equipped Caterpillar D4.
Lastly, there was the Model F Tournacrane, which could lift loads up to 4000lbs (1800kg). These attachments were all interchangeable with the Q Carryall and could be changed over within an hour by two men.
The New Zealand connection
To the very best of the author’s knowledge, no LeTourneau D & Q combinations were imported during the time period when the machine was in active service.
They may have passed through on their way to the Pacific war, but none apparently stayed behind. There is, however, an example of the type in the Packard Museum in Northland. This has been restored to its former glory in US military garb.
For the model collector
It will probably come as no surprise that no models of this machine exist in any scale.
It would make a great project for a larger scale (1:25) model, as even in this larger scale, it would not take up too much space. A 1:50 scale example would be miniscule by comparison.