Air Force Eyes Reducing Jets’ Fuel Reserves


While the services are being pretty tight lipped about their plans to achieve the billions in efficiency savings mandated by Defense Secretary Robert Gates, last week Air Force Lt. Gen. Philip Breedlove gave a hint of one proposal the air service may have on the table; fuel savings.

Yes, this seems like a no-brainer, especially since the Air Force has long said it needs to trim its gas consumption, but it’s how the service might do this that is interesting. “Is four-hours of reserve fuel on a C-17” really necessary, Breedlove, who is in charge of Air Force plans, operations and requirements, asked during a breakfast with reporters in Washington.

Instead of four hours of extra fuel, maybe the jets should fly with a two-hour reserve over the continental U.S. and a three-hour reserve over international airspace, he suggested.

The Air Force is the largest energy buyer in the federal government, spending almost $7 billion a year on fuel, and has long been looking at ways to trim its massive energy costs, from flying more direct routes to flirting with the notion of buying subsidized-coal-based jet fuel.

It’s already increasing the use of simulators to offset the cost training missions, is experimenting with algae based-jet fuel (along with the Navy)and plans to cut its energy costs in half by the middle of the next decade.

Still, trimming reserve fuel requirements is likely to raise eyebrows with some folks who have safety concerns.

— John Reed

  • Brian

    The sheer weight of hauling all of that fuel around decreases the overall efficiency of the aircraft, especially on climb out and flight-level changes. even if you’re not going to use it, you do use more fuel carrying it around.

  • Sanem

    ah yes, how could the Air Force possibly save on expenses?…

    speed up UAV purchases
    – cheaper to train pilots
    – fewer training flights needed
    – less wear and tear on airframes because less in the air, thus longer service lives, less maintenance costs and less crashes
    – stop using actual aircraft pilots to fly UAVs
    – instead of blowing all that money on F-35s, restart the J-UCAS program
    – air defence UCAVs can be as cheap as 10 million each, so that’s 10 for every 1 F-35

    – stop using F-22s to intercept Russian reconaisance aircraft
    – stop using F-15s to bomb the Taliban

  • Mat

    flying f15,18,16 over Iraq and Afghanistan is a huge waste of resources and airframe life for completing a mission a jet or turbo prop trainer with sniper pod could do just as well in not better at a fraction of cost..

  • carg

    Typical commercial airliners have about 45minutes of reserve fuel. 4 hours is a bit excessive especially for routine flights – ferry, cargo etc

  • prairie

    Fuel is heavy to haul around. All the commercial airlines started saving a lot of money by flying with a reserve, but not an excessive reserve.

  • elgatoso

    Make another program like Tory or NERVA

  • dreifma

    In a non wartime environment, flying with a smaller, but safe reserve makes sense and will save dollars. This should not be continued in combat zone.
    We should also park the F-22, B-2, and F-15E except for necessary training. Since we wont be getting anymore of these in the foreseeable future, we should conserve our airframe hours.
    With those savings we should buy more F-22 and add some of the F-35’s capability till its ready to actually do the mission that is promised.

  • Sanem

    @ Blight:

    “With regards to UAVs: the crash rate is still higher than for manned aircraft, since errors in transmission can trigger the crash sequence. At the moment our UAV force depends on long range satellite links to communicate, we may need to invest in next-gen means to communicate with UAVs that may have reduced latency or vulnerability to space conditions.”

    excellent point: why does the Air Force insist on flying their UAVs hands-on all the time, when the army has proven beyond doubt that their automated landing system results in less accidents? the Global Hawk takes off, flies around the globe and lands without any need for human intervention, and as technology evolves UAVs will become more and more independant, to the point where operators only need to confirm targets and give attack clearance (which is what happens with the current manned aircraft just the same)

    good news though: the AQ-10 program aims to have the men on the ground help guide the aircraft to it’s targets, even taking direct control for the attack run. this way the guys in the middle of it get to call the shots, since they have the best sense of the situation. it will also allow for easier communication, not much different from the way they use their mini-UAVs to look behind the next hill

    • greg

      Why not just keep the pilot in the a-10 for perception awareness? You could still add all of the sensors.

  • fred

    I agree, we need to ground ALL MILITARY air craft and focus on saving broken down cruise ships, supplying spam sandwiches too the cruise line paying customers. THE NEW AMERICA ,,

  • Curt

    You could probably even go beyond a simple 2 hours over CONUS and 3 hours in international airspace and not effect safety. For instance, for a flight over CONUS that will have good weather and never have an acceptable divert field more than 30 minutes from your route, maybe a hour of fuel reserve is acceptable. Not all international air space is the same. If I am flying inside NATO in good weather with a myriad of divert fields, an hour might also be acceptable. This seems to be such a no brainer as to wonder why it was never done before. As a side benefit, you would also reduce fatigue on the airframe although that is probably not going to be significant in the long run.

  • paul

    No one flys with a 4 hour reserve.

  • blight

    You might get more play out of making military personnel fly commercial where possible as well. VIP generals get access to planes and military golf courses (I kid you not…)

    • jon


      I do Air transport for the military, majority of the military flies commerial or rented commercial seats to where ever they go. VIP generals usually only go on private aircraft for official business, … though sometimes not. I kid you not, I have seen a general flying commerial with other military!

  • roland

    We need to ground all aircraft and use it if there is a threat or border incursion by other country like Iran, N. Korea, Russia, China or others until the economy is back to normal. Just maintain it until we need to use it to save and maximize the use of algae fuel to help save on petrolium cost.

  • Matt

    What began as a discussion of in-flight fuel reserves has devolved into a discussion of UAV’s, pilot pay, services budget competition, alternate fuels and memories of WW2.

    Aircraft consume additional fuel due to excess weight carried because of the induced drag produced by the lift vector (basic aerodynamics). The additional induced drag requires increased thrust to maintain flight which increases fuel consumption. A modern jet aircraft incurs a penalty of 3-4% of its weight in fuel per hour to sustain flight. Therefore, for each hour of flight carrying 100 pounds of excess fuel, 4 more pounds of fuel to be burned to carry this weight. This imposes a tremendous system-wide cost if not carefully controlled.

    The age of “fill-er up” is over. The fuel load is tailored for each flight allowing for required alternates and the cargo load. Four hours reserve fuel is a gross overestimate of the necessary fuel reserve. Typically, FAA reserves require 45 minutes reserve for IFR flight in addition to filed alternate fuel – if any is required. Typically, 60-90 minutes fuel reserve is required for international flights.

  • Andy

    I am curious as to where the General gets his information. I am a C-17 pilot, and we fly with the FAA required 45 minute fuel reserve in addition to 15 minutes of “contingency” fuel. Not sure how this adds up to 4 hours… We routinely land very near our minimum fuel as required by our tech order.

  • GuamVet

    When I was flying the KC-135, we carried just a 1 hour fuel reserve for peacetime missions. Why does this General tink aircraft carry a 4 hour fuel reserve? Most fighters cannot carry that much fuel with full tanks and no air refueling.

  • David Stroebel

    All of you make great points. Why isn’t anyone at the Pentagon listening?

  • Jose Trevino

    Eliminate all Senior Enlisted Advisor Positions–Senior First Sergeants should serve as enlisted advisors to the Commanders as an additional duty. Also, eliminate all Deputy Base Commanders, the next most senior officers should serve as Deputy Base Commanders when required. In the absence of the Commander, the next senior officer assumes command.

    This would save millions throughout the Air Force. The same concept could be considered for the other sister services.

  • Ollie Capra

    Cut back and or eliminate all the useless travel going to staff assistance visits, site surveys and conferences. All the useless trave shoud be eliminated. You’ll save a heck of a lot of money

  • Jose Trevino

    Folks: Read and study the Merida Initiative (Plan)–“You Tube” Also called: “Mexico Plan”

    A prime area to better conserve our DOD Funds!

    Read and draw your own conclusions!

  • Harvey

    22 years of flying Air Force cargo planes and I don’t ever recall carrying four hours of reserve fuel. Maybe the well meaning general should come out into the sunshine and stop breathing the stale air of his office.

  • Jose Trevino

    Harvey: Please show some kindness and respect for our Generals! Thank you SIR!

    Sergeant Major (Ret.)

  • Alex

    Saving money, and not spending as much is not really going to help our situation all of to much. What this country really needs is for the goverment and the general public to find a way to stop the decline of the USD worth, and to start raising the worht of the dollar. Me personally i think investing in goverment bonds, like in WW II, would be a start. Then the goverment can stop paying foriegn goverments with money we don’t have! Next they could start investing in local companies, and make our economy/regualtions more stable. At this point the worth of the dollar will start to raise, and companies will be more willing to do business in the United States!

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