Defense

October 12, 2012

‘Vortex surfing’ could be revolutionary

The view from a C-17 cockpit while trailing behind another C-17 during the first tests of “vortex surfing” at Edwards Air Force Base, Calif., Oct. 2, 2012. Early indications from the tests promise a reduction of fuel consumption by up to ten percent.

Migrating birds, NASCAR drivers and Tour de France bicyclists already get it. And now the Air Force is thinking about flying gas-guzzling cargo aircraft in formation – ‘dragging’ off one another – on long-haul flights across the oceans.

Flight tests with C-17s “vortex surfing” at Edwards Air Force Base, Calif., Sept. 6 and Oct. 2, have demonstrated potentially large savings of fuel and money by doing what geese do naturally. Tests show that flying in formation might be smarter than flying alone for Airmen, and not just for birds.

As one effort in the Air Force drive to reduce its overall fuel consumption, vortex surfing may be the wave of the future.

“The concept, formally known as Surfing Aircraft Vortices for Energy, or $AVE, involves two or more aircraft flying together for a reduced drag effect like what you see with a flock of geese,” said Dr. Donald Erbschloe, the Air Mobility Command chief scientist.

A series of test flights involving two aircraft at a time, allowed the trailing aircraft to “surf” the vortex of the lead aircraft, positioning itself in the updraft to get additional lift without burning extra fuel.

Early indications from the tests promise a reduction of fuel consumption by up to 10 percent for the duration of a flight. Over long distances and with even a small fraction of Air Mobility Command’s average of more than 80,000 flights a year, the fuel and cost savings could reach into the millions of dollars, experts say.

Next up: The Air Force Research Laboratory will analyze the data from for possible applications to other aircraft on a variety of missions.

Dr. Erbschloe said larger air mobility aircraft like the C-17 can fly in formations that are potentially easy to maintain and which do not require the planes to be exceptionally close together.

“The test flights were flown at longitudinal separations of 4,000 or greater,” said William Blake, one of the key developers of $AVE at the AFRL.

According to AFRL officials, modified C-17 formation flight system software enabled precise auto-pilot and auto-throttle systems to ensure the trailing aircraft achieved and maintained proper flight position without active assistance from pilots.

“The autopilot held the position extremely well — even close to the vortex,” said Capt. Zachary Schaffer, an aircraft commander on one of the test flights. “The flight conditions were very safe; this was as hands-off as any current formation flying we do.”

The first C-17 flight tests employing “vortex surfing” were conducted at Edwards Air Force Base, Calif., Sept. 6 and Oct. 2, 2012. Surfing Aircraft Vortices for Energy, or $AVE, involves two or more aircraft flying together for a reduced drag effect to save fuel.

Other pilots found differing levels of ride quality and discovered some flight test points might be difficult for long-endurance flights.

“The key will be finding the right balance of quality for improving fuel efficiency and ride,” said Maj. Eric Bippert, another aircraft commander on one of the test flights.

Bippert said being a part of the test program with so many talented engineers was a remarkable experience, and the concept could eventually impact global air transportation, overall.

“AMC has done really well with fuel efficiency at the operational level,” said Erbschloe. “The command has worked to gain efficiencies from the ‘low-hanging fruit’ such as optimizing flight routing, reducing weight where possible, and by not carrying excess fuel. $AVE offers significant efficiency gains, if employed in concert with these initiatives.”

He said early indications show the tests meet AMC criteria of the concept regarding safety and minimization of aircrew and aircraft strain while also being operationally sensible with a viable return on investment.

“AMC consumes 20 percent of the fuel used by the overall federal government, so we’re constantly looking for pragmatic ways to improve our fuel efficiency,” said Erbschloe.

“Assured energy advantage for our Air Force is only possible through revolutionary energy initiatives like $AVE,” said Dr. Mark Maybury, Air Force chief scientist, upon hearing the results of the tests.

The $AVE concept was previously highlighted in the 2011 Energy Horizons study, sponsored by the Secretary of the Air Force and chaired by Maybury.

The tests were the culmination of an ongoing, combined effort between AMC, the AFRL, the 412th Test Wing, the Air Force Life Cycle Management Center, the Defense Advanced Research Projects Agency, the Boeing Company and NASA Dryden Flight Research Center.

 




All of this week's top headlines to your email every Friday.


 
 

 

Headlines September 19, 2014

News: McKeon on broader military authorization: Anything can ‘fail or pass’ - Rep. Howard “Buck” McKeon, R-Calif., chairman of the House Armed Services Committee, said if Congress returns after the midterm elections to weigh a broader military authorization for the battle against Islamic State, it might not pass. Defense contractor gets 7 years for giving secrets...
 
 

News Briefs September 19, 2014

U.S. military deaths in Afghanistan at 2,203 As of Sept. 16, 2014, at least 2,203 members of the U.S. military had died in Afghanistan as a result of the U.S.-led invasion of Afghanistan in late 2001, according to an Associated Press count. At least 1,823 military service members have died in Afghanistan as a result...
 
 

Pratt & Whitney, U.S. Air Force complete qualification for F135 engine testing

Pratt & Whitney, a United Technologies Corp. , together with its U.S. Air Force partner at the F135 Heavy Maintenance Center at Tinker Air Force Base, Okla., celebrated another significant milestone qualification for F135 engine testing at the Oklahoma City Air Logistics Complex. OC-ALC which in addition to engine testing is also qualified to perform...
 

 
Navy photograph

Triton has first cross-country flight from Palmdale

Northrop Grumman photograph The MQ-4C Triton Unmanned Aircraft System takes off from Northrop Grummanís Palmdale, Calif., facility Sept. 17 for its first cross-country flight to Naval Air Station Patuxent, River, Md. PALMDALE,...
 
 
Air Force photograph by Michael J. Pausic

Future of NATO: Adapting to a new security environment

Air Force photograph by Michael J. Pausic Gen. Phillip Breedlove informs the assembled crowd about the results of the recent NATO Summit and the areas of instability that affect Europe that have regional implications. Seated in...
 
 
Air Force photograph by Scott M. Ash

AFRL commander describes Air Force’s technology vision

Air Force photograph by Scott M. Ash Maj. Gen. Thomas Masiello takes a question from an audience member after discussing Air Force Research Laboratory breakthrough technologies during the 2014 Air Force Association’s Air ...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>