February 1, 2012  

Logistical fratricide

Light attack planes can reduce the heavy toll of supplying fuel for fighter jets

he Air Force has been continuously at war for more than 20 years. From the opening minutes of Desert Storm in 1991 to the present, there has not been a time when the Air Force has not been flying combat missions in support of national security objectives — usually in more than one location and often in more than one theater.

The vast majority of that burden has been borne by the fighter force. The effectiveness of that force and its versatility are undisputed. However, these operations have not been without their challenges, particularly logistical challenges.

Combat operations in the ’90s were easy to support logistically, flown as they were from NATO, Saudi Arabian and Kuwaiti air bases under permissive conditions. However, since the early days of Operation Enduring Freedom, when A-10s moved into Afghanistan, the logistical burden of supporting our fighters has jumped precipitously because the supply routes into Iraq and Afghanistan have never been free from hostile threats.

With the high fuel consumption of fighters comes a need for an intensive logistical effort, costly in both dollars and casualties. There is no question that the high fuel consumption of jets places a heavy burden on supply lines and results in significant numbers of casualties due to enemy action. If there were no alternative to fast-jet tactical air, this would largely be an unavoidable burden. But modern, turboprop-powered light attack aircraft offer a capable, viable alternative for providing air support in irregular conflicts. Modern turboprop light attack aircraft, operating in place of some legacy fighters in Afghanistan, offer an opportunity to greatly reduce the fuel burden imposed by air operations and concurrently reduce the number of Purple Hearts awarded to service members and families.

Aircraft, particularly jet aircraft, use a great deal of fuel. The Air Force is the largest consumer of fuel in the Defense Department. In 2006, the majority of DoD’s fuel use, about 58 percent, was jet fuel, dwarfing the next-largest category, marine diesel (13 percent). In 2008, fuel deliveries to Iraq and Afghanistan exceeded 90 million gallons per month — 20 percent of the DoD consumption. While the overall consumption of petroleum increased only slightly between 2004 and 2008, the dollar cost increased threefold. Because of the poor in-ground petroleum transport infrastructure, the heavy use of fuel in Iraq and especially in Afghanistan can be directly tied to casualties incurred by ground operations required to get the fuel to U.S. bases. Overall, roughly half of the total tonnage hauled overland is fuel.

In Iraq and Afghanistan, the tie between fuel demand and casualties is significant and quantifiable. With fuel and water being the majority of the tonnage hauled, the Army has developed a model from historical casualty data. In Afghanistan, one U.S. soldier or contract civilian is killed or wounded for every 24 16-truck fuel convoys. In Iraq, that number was one per 38.5 convoys. During fiscal 2007, there were 38 casualties incurred moving 897 “average” fuel convoys in Afghanistan. The Army data do not include casualties among allied forces or the Marine Corps. The Marines track their data differently, but the Corps’ Expeditionary Energy Strategy does highlight the issue: “During a three-month period early in 2010, six Marines were wounded hauling fuel and water to bases in Afghanistan during just 299 convoys. That is one Marine wounded for every 50 convoys.”

The o-ax alternative

The direct link between fuel and casualties is not news. However, the impact of high fighter fuel consumption remains poorly understood and rarely discussed. If there were no alternative to the current tactical air fleet, the discussion would be moot. But for the kind of irregular warfare challenges faced in Iraq and Afghanistan (and elsewhere), there is a viable alternative: a turboprop-powered light attack aircraft. The proposed aircraft is not notional — modern light attack aircraft are flown by a number of air forces worldwide. Air Combat Command has a designation for its proposed light attack aircraft: the OA-X. Among its other capabilities, the fuel consumption of the OA-X will be a fraction of the consumption of fast jets.

OA-X, while a notional designation, is not a fantasy airplane. Two examples exist today — the Hawker Beechcraft AT-6B Coyote and the Embraer EMB 314 Super Tucano (also called the A-29). Internally, these aircraft look like advanced fourth-generation fighters and have similar air-to-ground capabilities, using identical weapons, with similar weapons delivery capabilities. What they lack in top speed, they gain in mission endurance. But the key premise upon which this thesis is based is that these aircraft have essentially the same air-to-ground capability as today’s jets (discounting the A-10’s 30mm cannon), with similar or better sensors and communications. The issue with the fast jets is not their capability but the penalties associated with bringing that capability to the battlefield.

There are a number of things that distinguish light attack aircraft from legacy jets. They have no more air-to-air capability than the A-10. They have no realistic capability to operate in an environment dominated by radar-guided surface-to-air missiles. But in environments devoid of these threats, they provide a ground attack and reconnaissance capability equivalent to the F-16 fighter jet, with more endurance and more basing options. A combat-loaded F-16 carries three external fuel tanks (or two and an electronic-countermeasures pod), four air-to-air missiles, four 500-pound laser-guided bombs on two pylons, a targeting forward-looking infrared and an internal rotary cannon. A Super Tucano loads up with four 500-pound laser-guided bombs on four pylons, one external tank, a targeting FLIR and internal wing guns. The AT-6B loads up in a similar fashion with more pylons but external gun pods taking up the extras. Discounting a need for air-to-air missiles, the warloads are identical.

The OA-X provides two additional capabilities that are not currently resident among the legacy fleet: true independence from aerial-refueling tankers and the ability to operate effectively with a fraction of the fuel support. The Super Tucano, with weapons onboard, uses around 330 pounds of fuel per hour in cruise. An F-15E will burn that much fuel in six minutes while taxiing on the ground. In March 2010, the AT-6B and T-6C flew 24 sorties in the Joint Expeditionary Force Experiment at Nellis Air Force Base, Nev. In total, the aircraft flew 46 flight hours and burned 15,640 pounds of fuel (averaging 340 pounds per hour) — around the amount it takes to fuel a two-tank F-15E to half capacity. On a per-hour basis, an OA-X will use between 3 percent and 5 percent of the fuel of an F-15E and 6 percent to 10 percent of an F-16C. A single 5,000-gallon fuel truck, sufficient to top off an F-15E for a two-hour sortie, will supply an OA-X for more than 90 hours of flight.

How much of convoyed fuel is dedicated to fighter operations is impossible to pinpoint without access to classified data, but a reasonable comparison with the F-16 can be made. Assuming that ground-delivered jet fuel accounts for only 25 percent of the fuel used by forward-based F-16s (the rest being delivered by air) compared with 100 percent of the OA-X fuel requirements, OA-X operations reduce the requirement for ground-trucked fuel by 60 percent to 76 percent, for the same number of flying hours.

Starting in 2004, the Air Force undertook an effort to remove trucks from the roads by stepping up airlift of cargo in Iraq and Afghanistan. C-17 and C-130 operations, including airdrops, are used to reduce the number of ground combat logistics movements required. This effort came at a significant cost in fuel consumed and hours flown by airlift aircraft but had a measurable effect. In Iraq in the first quarter of fiscal 2007, Detachment 2 of the 332nd Expeditionary Logistics Readiness Squadron based at Quayyarah West moved 1,100 pallets by air, removing 333 trucks from Main Supply Road Tampa. While the Air Force highlighted air mobility efforts to take trucks off the road, combat operations from Balad were keeping trucks on them. Had we possessed OA-X, the reduction in fuel demand would have taken many more trucks off the road. Replacing a squadron of F-16s with OA-X flying the same number of sorties would have resulted in 1 million pounds (164,000 gallons) savings of ground-delivered fuel per 100 sorties, taking 26 fuel trucks off the road per 100 sorties. Assuming a very low estimate of 40 sorties per day, the effect of reduced fuel consumption removes those same 333 trucks from the road in 32 days and a total of 936 fuel trucks from the road in the same three months, with a concurrent reduction in casualties — all while not using a single airlift sortie. A full year’s worth of OA-X substituting for F-16s adds up: 14,600 sorties, 153.3 million pounds of truck-delivered fuel saved, removing 91 16-truck fuel convoys from the road. Under conditions where the sortie rate is higher, the reduced fuel burden becomes even more significant, requires comparatively less demand for ground transportation and allows more flexibility in meeting the overall requirements of “surge” operations.

AN irregular warfare solution

The profound effects in Iraq and Afghanistan are country-specific but have large implications for the future of the Air Force. If historical patterns hold, and there is no reason to suppose that they will not, future conflicts are likely to be irregular warfare. If the Air Force is to reliably present persistent combat air power in support of ground forces without facing significant logistical challenges and attendant risk, it requires aircraft that are much more fuel efficient than legacy or fifth-generation jet fighters. Worldwide, the massive fuel requirements of the legacy fleet supported by aerial-refueling tankers, to say nothing of the basing requirements, may well prevent air operations from being considered. It would be highly detrimental for the nation if an Air Force consisting mainly of older jets and F-35s is not employable for any length of time over much of the world.

Not so with the OA-X. The ease of supplying the OA-X in the field is an entirely different enterprise from supplying legacy fighters. With a little C-130 support, light attack aircraft can be supplied from the air with far greater ease than thirstier jets.

In future conflicts, tanker basing could become problematic. Tankers take up a lot of ramp space, require a great deal of fuel and are an obvious indication of a significant U.S. footprint. The ability to locally base persistent tactical air that is completely independent of a tanker effort would be a welcome addition to the Air Force’s capabilities. It is even possible to supply light attack aircraft entirely by airlift. The ubiquitous 18,000-pound fuel bladder can be delivered by a C-130 and filled from the C-130’s own tanks, using 30 percent of the fuel capacity of a C-130H for more than 40 hours of flying time for light attack. In cases where local resources must be used and large fuel trucks are few and far between, a light attack aircraft can be topped off from four 55-gallon drums with fuel left over.

In many cases, it is true that we have to spend money to save money — OA-X will not materialize without funding. It is similarly true that money has been spent in large amounts for procurement of mine-resistant, ambush-protected vehicles (MRAPs), which were deployed because they saved lives, not because they were vastly improved fighting vehicles. To date, however, the Air Force has missed its “MRAP moment,” so far not making a significant investment in light attack procurement. This is particularly perplexing when one considers that the purchase of 200 OA-X planes would likely pay for itself in operations and maintenance, and fuel costs alone before the last OA-X rolled off the production line, even if the costs of tanker support are not figured in.

In August 1966, a year and a half after the first F-4 Phantoms arrived in Thailand for operations over Vietnam, the Air Force directed Combat Dragon, a combat evaluation of the A-37A, a light attack aircraft modified from the T-37 trainer. Within a year, A-37s were deployed to Bien Hoa Air Base in Vietnam, conducting close-air support, attack, interdiction and combat search-and-rescue missions. The evaluation was successful, highlighted the comparatively low fuel and maintenance requirements and high effectiveness of light attack, and led directly to the development and procurement of the A-37B.

Today, 10 years after the start of Enduring Freedom, the Air Force has not undertaken a similar effort. Despite the high operations costs of legacy jets, there has been no combat evaluation of turboprop light attack aircraft operated by and for the joint force. It would be well worth demonstrating the comparative capabilities of this kind of aircraft and reconsidering the Air Force’s exclusive reliance on high-performance, supersonic aircraft in cases where they are not the only practical option. If the high cost in dollars does not make a convincing argument (and to date, it has not), then the unnecessary cost in casualties should. AFJ