DoD’s love affair with petroleum
The United States Department of Defense (DoD) mirrors American society in many ways, and energy consumption is no exception. The Executive Branch has been pushing DoD for several years to reduce its energy consumption in order to reduce its oil dependence, minimize its generation of Green House Gases (GHG) and, of course, save money. To accomplish these goals, DoD will have to change not only its culture and way of doing business but also the tools it uses in executing its missions around the world. The American public has shown very little real progress in changing its behavior. As energy (petroleum) prices stabilized in 2009-2010, the demand for more fuel-efficient vehicles subsided and the sales of light and medium trucks increased. It is highly likely that DoD’s response will mirror this behavior as well.
The Federal Government accounts for 1% of the nation's total energy consumption and 2% of total petroleum use. In both of these categories, DoD is by far the largest government consumer (0.9% of national energy use and 1.8% of national petroleum consumption). In 2008 this equated to 120 million barrels of petroleum-based fuels, which were 75% of DoD’s total energy use. The vast majority of this fuel was used for operations. Unlike the private sector, the cost of using these liquid fuels for military operations involves more than just the “price at the pump.” The “fully burdened cost of fuel” includes the cost of transportation to the area of operations, the cost of protecting the supply lines, and the cost of limited tactical and strategic options due to the dependence on it. These costs can raise the total pricetag by an order of magnitude. The military’s recent revelation about the true cost of operational fuel has generated a great deal of heat but very little light.
Just as US consumers have the option of trading in their gas guzzling trucks and sport utility vehicles for more fuel efficient hybrid vehicles, or of shifting to carpools and mass transit for commuting to work, the military could shift from high performance manned aircraft to gas sipping unmanned aircraft and, instead of flying troops halfway around the globe, could send them in DoD’s idle fleet of troop transport ships. But the military is making only token gestures in these areas and, just like their civilian counterparts, sending the signal that any significant change will require a true crisis and considerable time. For the foreseeable future, the military and US consumers will continue to operate, for the most part, as they always have.
Time, distance, convenience, and petroleum
When it comes to reducing a budget, whether it is a fiscal budget or an energy budget, the biggest gains to be had are in the largest budget categories, and for DoD that means the operational energy budget. Over 70% of the energy consumed by DoD goes towards operations. This includes energy for aircraft, ships, tactical vehicles, and expeditionary bases used in training, deploying, and sustaining our armed forces around the world. Since operational forces are mobile by nature, they demand fuels with the highest possible energy density and transportability, namely petroleum based fuels. For moving large quantities of people and material around the world, the most “energy efficient” means is by ship and the least is by air. Conversely, the most “time efficient” means is just the opposite. As America and the rest of the industrialized world has become addicted to “just in time” and “overnight” delivery of every imaginable commodity, so has DoD. The US military’s consumption of petroleum in FY 2008 was 120 million barrels at a cost of approximately $16 billion, and roughly 73% of this petroleum was used for aviation.
The Air Force uses more than half of DoD’s petroleum, and it comes as no surprise that 94% of it goes towards aviation. But it may be surprising that 51% is for aviation-based transportation of personnel, material and even aviation fuel (for in-flight refueling). Only 28% of Air Force consumption goes towards fighter/attack aircraft and just 7% for bombers. The Air Force of the 21st century has slowly transformed itself into a military version of FedEx and Southwest Airlines, but only a small fraction of their cargo is ordnance. Conversely, slightly more than a third of the petroleum used by the Navy goes towards aviation, but unlike the Air Force the vast majority of it goes towards fighter/attack aircraft that are almost solely aircraft carrier based. This homogeneity of naval aviation provides the equivalent of a natural experiment for investigating the fuel cost and the carbon footprint of one of DoD’s principal means of conducting warfare, and perhaps the ways to reduce it.
For the last two decades the primary role of the US carrier air wing has been force projection against ground forces as manifested during multiple joint operations against ground forces in Iraq, the Balkans, Iraq (again) and Afghanistan. Even though the air wing has enormous capability in a broad set of mission areas, it is likely that the focus of the last twenty years will continue for the foreseeable future. This sustained trend of singular mission area operations facilitates a rough calculation of the fuel use associated with the operations and, through extension, the Fully Burdened Fuel Cost and “Carbon Footprint.”
Strike pilot flight time requirements vary across these periods but are roughly 30 hours per month during work-ups and deployment, and 20 hours per month during post deployment stand-down. The resulting planned average of 26.66 hours per month for each strike pilot over the 18 month cycle is very close to the historical average of 24.5 hours per month as reported by the Naval Air Training Command and Naval Air Safety Center over the last twenty years. Using these two values, we can determine that during a standard deployment cycle the 60 strike pilots who constitute the “Tip of the Sword” for the carrier air wing will fly a total of somewhere between 26,460 and 28,792 flight hours.
The number of flight hours is a critical metric as it allows us to compute the total amount of fuel consumed by the four F/A -18 squadrons of the air wing during the deployment cycle. The Charlie and Echo variants of the Hornet are very different aircraft, with the Echo being almost 25% larger/heavier and consequently having higher specific fuel consumption per hour of flight time. As the number of the two variants within the air wing is roughly equal and the flight hour requirement per pilot is independent of type, we can use the average fuel consumption of the two, which is approximately 1,000 gallons per hour of flight time. The total fuel consumed by the four strike squadrons during the 18 month deployment cycle is therefore 26-28 million gallons.
The cost of fuel used by naval aircraft depends on one’s perspective and accounting method. The basic cost of purchasing the fuel (JP-5 for sea use & JP-8 for land use) is fairly straightforward, but only captures part of the cost. The cost of fuel pumped from ground storage in the US during basic land-based training is at the lower end of the spectrum, whereas the cost of fuel delivered by in-flight refueling during overseas tactical operations is at the higher end. Fuel delivered by navy supply ships to the carrier while underway for further flight-deck transfer to aircraft is somewhere in between. The only audited numbers that are available are based on the purchase price of the fuel and therefore represent the very lower end of the spectrum. Data published by the Navy Visibility and Management of Operating and Support Costs (VAMOSC) management information system show that for FY97-FY08, the per flight hour fuel cost in constant FY09 dollars, for operating the F/A-18C and F/A-18E is $2,100 and $2,600 respectively (these numbers do not include fuel cost during deployment.) As the number of each type of aircraft and hours flown is roughly equal within the air wing we can use an average cost per flight hour of $2,350 for the four Hornet squadrons. When this average fuel cost per strike flight hour is multiplied by the range of flight hours calculated above, we get a fuel purchase cost for the 18 month deployment of between $62 and $67 million. The actual delivered cost of the fuel for various operational scenarios clearly needs to be thoroughly analyzed. It is not hard to imagine that it may be as much as an order of magnitude higher at the upper end of the spectrum such as in-flight refueling from Air Force tankers while en-route and returning from missions over Afghanistan.
Image: F/A-18 In-Flight Refueling
An F/A-18 Hornet from the aircraft carrier USS Kitty Hawk (CV 63) receives fuel from a US Air Force KC-135R Stratotanker. DoD photo by Staff Sgt. Bennie J. Davis III, US Air Force. (RELEASED)
The point of this analysis is to determine the fuel cost and “carbon footprint” associated with a carrier air wing conducting its primary mission of the last two decades, namely force projection against ground forces. Just as gallons of fuel burned by the strike aircraft during the 18 month deployment cycle is the unit of measure for calculating the costs and footprint (the numerator), ordnance delivered during the deployment is the ultimate metric of force projection (the denominator). By tallying the number of bombs or pounds of ordnance delivered, we can then calculate the fuel cost (purchase price) per bomb delivered and / or the carbon cost.
The amount of ordnance delivered varies greatly depending on the operational tempo of the air wing during its on station time. During operation Desert Storm in January and February of 1991, strike aircraft of Air Wing Five operating off of the USS Midway delivered approximately 4,000 bombs. During the summer of 2007 while supporting combat operations in Afghanistan, strike aircraft of Air Wing Nine operating off of the USS Stennis delivered 160 bombs. Using these two examples as a high and low end of the spectrum we can calculate the range. (The CVW-5 expenditures during Desert Storm are the highest reported since Viet Nam. The CVW-9 expenditures in the summer of 2007 are not the lowest. The lowest during the last twenty years is several cases of zero ordnance expended. The 160 is actually very close to the median for the last five years.) In the Desert Storm example, the fuel expended per bomb delivered is 6,615 gallons at a purchase cost of $15,545 and an associated “carbon footprint” of 71 tons of CO2. In the summer of 2007, in the CVW-9 example, the fuel expended per bomb delivered is 165,375 gallons at a cost of $388,631 and a “carbon footprint” of 1,771 tons of CO2.
It quickly becomes clear that the acquisition cost of the laser or GPS guided bombs, a cost that the acquisition community obsesses over, pales in comparison to the larger systematic cost of the fuel required by just one part of the overall “weapon system” that delivers them from a factory in the US to the target in Afghanistan. It wasn’t until oil prices exceeded $100 per barrel in the spring and summer of 2008 that DoD’s acquisition community began to take a different perspective on the cost of individual weapons and began to explore the full system cost, with a particular emphasis on the fuel cost which had previously been buried in the overhead or operational budgets.
Image: F/A-18 Flight Deck Re-arming
F/A-18F Super Hornet assigned to Strike Fighter Squadron Forty One (VFA-41) is uploaded with ordnance. US Navy photo by Photographer's Mate 3rd Class Philip A. McDaniel. (RELEASED)
This rough analysis and its findings are subject to numerous attacks. Carrier and strike aircraft advocates would rightfully argue that the numbers are highly skewed by focusing on only one aspect of the carrier air wings' broad range of capabilities and uses. Others would argue with equal veracity that the numbers are far too low and should actually account for the full operating expense of the carrier itself and the full air wing. The methodology and data used and the results obtained, given the stated premise and assumptions, are very straightforward. The analysis can easily be repeated given different boundary conditions for what costs should and should not be associated with the delivery of the ordnance, as well as the metric of performance such as whether we should count bombs delivered or, perhaps more importantly, targets destroyed. We could use a fully burdened average cost of fuel (estimated to be in the vicinity of $10 per gallon), account for the fuel used by the entire air wing as they are all in one way or another in support of the attack aircraft (50 million gallons per 18 month cycle), and use the number of targets destroyed on a typical deployment as our performance metric (50 targets per deployment average over the last 20 years). For each target destroyed this works out to 1 million gallons of fuel at a cost of $10 million and the release of 11,025 tons of CO2. Hardly a sustainable proposition given that the target is generally a handful of Taliban insurgents in sport utility vehicles or mud and brick structures.
The “cost” of pilots
As illuminating as some of these numbers are, one of the principal factors that the analysis reveals is how heavily the results are driven by the non-combat flying hours required for obtaining and maintaining pilot proficiency. With only four months of the 18 month deployment cycle spent on the front lines, the fuel burned for pilot training and proficiency during the other 14 months has no direct war-fighting value and serves as a huge fuel (and CO2) overhead cost of carrier aviation. This fact is not lost on the Navy or Air Force. With the ever-growing cost of operating tactical jets and the vast improvements in the quality and realism provided by flight simulators, both services have worked to supplement actual flight hours with simulator time, when not forward deployed. But even the most advanced simulators fail to fully replace actual flight hours. Detailed studies of monthly and annual aviation mishap rates have shown a direct correlation to monthly flight hours. Simulators can help supplement actual flight time when used to train pilots in new aircraft, weapons and tactics, but all attempts at using them to substitute for the monthly minimum of 20-30 hours of actual flight time have resulted in an increase in mishap rates.
To avoid the cost of non-tactical flight time, the most direct approach is to completely remove the pilot from the cockpit. Radical yes, but well within the technological state of the art and already employed, to a limited but growing degree, by the Air Force in Afghanistan with the Predator and Reaper Unmanned Combat Air Vehicles (UCAVs). Unmanned combat aircraft bring more fuel savings than just the elimination of almost all non-tactical flying. They are also much more fuel efficient on combat flights than their manned peers such as the F/A-18 in the Navy and F-15 and F-16 in the Air Force.
Image: MQ-9 Reaper Firing Hellfire Missile
An Air Force MQ-9 Reaper UCAV firing an AGM-114 Hellfire missile. US Air Force Photo (RELEASED)
The greatest resistance to expanded use of UCAVs in both the Air Force and Navy has been cultural and political. The history, image, culture, and human institution of manned aviation in the military services are nearly a century old and as strong as ever. UCAVs and other unmanned aviation assets are not proposed as a means for the wholesale elimination of manned aviation in the military. There are several roles for which a pilot in the cockpit may always be essential, but it is clear that unmanned ones could handle a large number and perhaps even the majority of aviation missions that are presently conducted by piloted aircraft.
The enormous systemic fuel cost of utilizing modern fighter and attack aircraft to engage the Taliban in Afghanistan is not an indictment of the US military’s capability but rather a symptom of asymmetric warfare. The high degree of advanced weaponry and capability of the military is the cumulative result of a half-century preparing for a potential battle against the former Soviet Union. Spending a half million dollars in fuel to enable an F/A-18 to destroy a surface to air missile site or main battle tank in a highly contested battle space is a bargain. Utilizing the same weapon system to engage low value targets in an unopposed battle space shifts the long-term strategic advantage to the adversary. This is borne-out by the near elimination of the Taliban in Afghanistan in the first few months of the war by the CIA and Army special forces operating on horseback and calling in air strikes on concentrated Taliban forces and targets. As the war shifted over the years to predominately garrisoned US ground forces and traditional Army tactics, the Taliban were able to stage a resurgence that has extended the conflict to nearly a decade at a monetary cost, to date, of over $350 billion.
From a domestic politics perspective the stakes are just as high (at least financially). The Air Force and Navy are in the midst of procuring the next generation of advanced, manned, tactical aircraft and the tankers required to fuel them. The Joint Strike Fighter and KC-X tanker represent $370 billion and $35 billion programs respectively. This wholesale continuation of arming to fight a peer military when none exists is done at the expense of fielding a future military with a better balance of high end and low end forces. Here, low end does not imply less capable or technologically advanced systems but rather weapon systems better suited to engaging low end adversaries such as pirates, terrorists, insurgents and other non-state forces. The current “estimated” unit cost for a Joint Strike Fighter is over $100 million and rising, while the “actual” unit cost for a Reaper is about $10 million and dropping as production increases. Shifting the future aviation mix towards more UCAVs and fewer manned aircraft would significantly reduce DoD’s acquisition costs, fuel costs, and carbon footprint while also better diversifying its war-fighting capability portfolio for an uncertain future. However, as such a change would have large negative ramifications for the aviation industry, Congress would likely resist it.
Aviation, as the US military’s largest energy sector, is also its largest petroleum user and greenhouse gas generator. The only significant effort DoD has made related to the elephant in the room is to certify a few aircraft types to burn various blends of petroleum / bio fuels (that are unavailable in any quantity and unaffordable even if they were) and to set limited goals for the introduction of their use. DoD is not going to stop using petroleum-based fuels any time soon. Until someone invents or discovers an equally energy dense, easily transportable and affordable fuel, the military will continue to rely upon petroleum. If DoD is serious about reducing their use of petroleum based liquid fuels to minimize their vulnerability to fluctuating oil prices, to reduce the logistics burden of transporting millions of gallons of aviation fuel around the globe and to limit their contribution to green house gases, they have a large part of the solution in hand. Their sincerity in doing so will be revealed not by listening to what they say but rather by watching what they do.
Dr. Beach is a Post-Doc Fellow at the Center for International Energy and Environmental Policy at The University of Texas at Austin. He is a retired Naval Officer and qualified Submariner, Naval Aviator, Surface Warfare Officer, and Acquisition Professional.