The "quality versus quantity" debate has raged in airpower circles for decades, but in these austere times it is the latter that seems to be gaining favour.

So far, the quantity issue has been most directly felt by the sudden popularity of manned turboprops by the US military's weapons buyers.

After spending a decade buying either thousands of mostly expendable unmanned aircraft systems or handfuls of super-capable fighters and surveillance platforms, the Department of Defense now wants to buy relatively simple, straightforward, manned turboprops for a wide range of mission areas.

Last year, the DoD practically forced the US Air Force to approve a plan to buy 37 MC-12 Libertys - a military variant of the Beechcraft King Air 350 - for intelligence, surveillance and reconnaissance.

More recently, the USAF has expressed new interest in single-engine turboprops to serve as light attack fighters for a potential irregular warfare wing. The USAF's new enthusiasm came about two months after the US Navy already acquired a handful of Embraer Super Tucanos.

Then come new indications that the US Army will switch its acquisition strategy for the Aerial Common Sensor programme from business jets to turboprops.

As any fixed-base operator knows, there is a huge price gap between the two types of platform. For an army customer, that premium has traditionally rendered the two key advantages of jet transport - speed and altitude - difficult to afford. Of those two categories, altitude is probably more significant for an intelligence platform. From 40,000ft (12,200m), an airborne sensor has a sweeping view of a potential battlefield, and can extend its reach deep into enemy-held territory without putting itself within range of defensive weapons.

By shifting to turboprops, army officials may simply be seeking to substitute quantity for quality. For a similar amount of money, the army could purchase a handful of sensor-equipped business jets or flood the airspace above the battlefield with manned turboprops.

The question now is whether demand for cheaper platforms of other aircraft types will be triggered.

It's hard to imagine the US Air Force backing off its commitment to fifth-generation fighters to buy significantly larger amounts of fourth-generation aircraft. But the US Navy may well make that trade-off. Another question is how the army decision could spill over into other surveillance platforms, such as the USN's plan to replace the EP-3E Aries turboprop.

Source: Flight International