Dec 9th 2010 | The Economist
JET fighters may be sexy in a Tom Cruise-ish sort of way, but for guerrilla warfare—in which the enemy rarely has an air force of his own—they are often the wrong tool for the job. Pilotless drones can help fill the gap. Sometimes there is no substitute for having a pilot on the scene, however, so modern air forces are turning to an old technology: the turboprop.
So-called light-attack turboprops are cheap both to build and to fly. A fighter jet can cost $80m; the 208B Caravan, a light-attack turboprop made by Cessna, costs barely $2m. It also costs as little as $500 an hour to run when it is in the air, compared with $10,000 or more for a fighter jet. And, unlike jets, turboprops can use roads and fields for take-off and landing.
It is not only jets that light-attack turboprops can outperform. Armed drones have drawbacks, too. The Reaper, made by General Atomics, can cost $10m or more, depending on its bells and whistles. A manned turboprop can bomb a target for a third of the cost of using a drone, according to Pat Sullivan, the head of government sales at Cessna.
There are strategic considerations, too. Piloted light-attack planes do not require the technical expertise and support systems needed by drones, but offer complete operational independence. And being lower-tech than many drones, they are less subject to restrictions on exports.
They are also better, in many ways, than helicopters. To land a chopper safely in the dirt requires sophisticated laser scanners to detect obstacles hidden by dust thrown up by the downdraught of the rotors. Such dust makes helicopter maintenance even more difficult than it is already. Maintaining turboprops, by contrast, is easy. According to Robyn Read, an air-power strategist at the Air Force Research Institute near Montgomery, Alabama, they can be “flown and maintained by plumbers”. Thrush Aircraft, a firm based in Albany, Georgia, claims that the Vigilante, an armed version of its crop-dusting plane that costs $1m, can be disassembled in the field with little more than a pocket screwdriver.
Turboprops are also hard to shoot down. Air Tractor, another firm that makes crop-dusters, branched out into warplanes last year. One reason was that a fleet of 16 unarmed versions of its aircraft had been used by America’s State Department to dust South American drug plantations with herbicide—an activity that tends to provoke a hostile response from the ground. Despite being hit by more than 200 rounds, though, neither an aircraft nor a pilot has been lost.
In part this is because of the turboprops’ robust design, and in part because Air Tractor’s fuel tanks have rubber membranes which close around bullet holes to slow leaks. Add extra fuel tanks, which let the plane stay aloft for ten hours, six 225kg precision-guided bombs and more than 2,000kg of missiles, rockets and ammunition for two 50-calibre machineguns, and you have the AT-802U, a formidable yet reasonably cheap (at $5m) warplane.
Light-attack aircraft now also sport much of the electronics used by fighter jets. The MX-15, an imaging device made by L-3 WESCAM, a Canadian company, allows a pilot to read a vehicle’s licence plate from a distance of 10km (6.2 miles). It is carried by both the AT-802U and the AT-6, a top-of-the-range light-attack plane made by Hawker Beechcraft.
Not surprisingly, countries with small defence budgets are investing in turboprops, including Brazil, Chile, Ecuador, Indonesia, Iraq, Lebanon, Morocco and Venezuela. And the biggest military establishment in the world also recognises the value of this new, old technology. America’s air force plans to buy more than 100 turboprops and the navy is evaluating the Super Tucano, made by Embraer of Brazil.
In aerial combat, then, low tech may be the new high tech. And there is one other advantage that the turboprop has over the jet, at least according to Mr Read—who flew turboprops on combat missions in Cambodia in the 1970s. It is that you can use a loudspeaker to talk to potential targets before deciding whether to attack them. As Winston Churchill so memorably put it: “When you have to kill a man, it costs nothing to be polite.”
