https://www.aviationw...channel=defense

Oct 6, 2011

By Graham Warwick

Lockheed Martin is testing winglets and other drag-reducing modifications to cut the fuel consumption of C-130 Hercules and C-5 Galaxy airlifters.

With large-scale wind tunnel testing completed, Lockheed is fabricating a shipset of winglets for flight testing on a C-130 in 2012. The modification could be available for both retrofit and forward-fit by early 2014.

Computational analysis and small-scale tunnel tests have been completed on the C-5 winglets. Large-scale tunnel tests are planned for 2012, leading to flight tests in 2014 “if the customer is interested,” says Jack O’Banion, director of advanced development programs at Lockheed’s Marietta, Ga., plant.

The 5-ft.-tall winglets are projected to reduce cruise fuel flow by 170 lb./hr. on the C-130J and “probably more” on older versions of the Hercules, he says. They are designed to be fitted to any C-130 with the beefed-up “enhanced service life” center wingbox. This has the extra structural margin to accommodate winglet-induced bending loads.

Winglets for the C-5M are 6 ft. tall and projected to reduce cruise fuel flow by 1,100 lb./hr. This is on top of the 8-20% improvement in fuel efficiency that comes with re-engining of the C-5 with General Electric CF6-80C2 high-bypass turbofans, O’Banion says, adding that the wing already has sufficient margin to accommodate the winglet loads.

Lockheed Martin in August flight tested an aft-body drag-reduction modification on the C-130. This comprises a series of 36 vortex generators mounted on the aft fuselage. These “microvanes” alter the aft-body flowfield to pull the underbody vortex closer in and reduce base drag, he says.

Results are still being analyzed, but indications are the microvanes will reduce total drag by up to 3.7%, O’Banion says, for a fuel-consumption reduction of 2-3%. No significant changes in aircraft handling have been observed, he says.

The vortex generators, mounted in rows on the aft fuselage on either side of the rear loading ramp, are planned to be available by the end of 2012 for forward-fit and retrofit to the C-130J and earlier Hercules.

Another fuel-saving modification being studied for older C-130s is an upgrade to the latest Series 3.5 version of Rolls-Royce’s T56 turboprop, coupled with Hamilton Sundstrand’s NP2000 eight-blade propeller.

For the C-5, Lockheed also is working on a drag cleanup that is expected to improve fuel efficiency by 2-3%. This would include new seals on the flight controls to minimize aerodynamic leaks that cause drag; and new seals in the pressurization system to reduce bleed-air demand on the engines and thus improve their fuel efficiency.

In addition, equipment installed on the C-5s over time — such as defensive systems — would be cleaned up to reduce parasitic drag. “We are in the process of laying out a detailed program for the Air Force, including the business case and potential benefits,” O’Banion says.

The C-130 and C-5 drag reductions are part of an initiative by the U.S. Air Force to cut its fuel consumption. Other elements include drag cleanups on the Boeing C-17 and KC-10 and engine upgrades on the KC-135.

Edited October 7, 201114 yr by NEflyer

"winglets are gay" vs. "winglets are the balls of airlift"

Winglets make a jet 20% cooler.

How much money would we have saved by now if they threw these on?

In fact in the mid-70s Boeing calculated a performance gain of 7.5% if the KC-135 was wingletted. Source

Besides...coolest winglet award goes to:

Edited October 8, 201114 yr by stoleit2x

How much money would we have saved by now if they threw these on?

With the additional CBTs, endless printing of -1 revisions, etc... It'd probably end up costing more. Its the Air Force way.

How much money would we have saved by now if they threw these on?

Those are the C-17 winglets being flight tested.

If you search the Rand AF project, there is an article that examines wingless on tankers. The cost vastly outweighed the gain.

If you search the Rand AF project, there is an article that examines wingless on tankers. The cost vastly outweighed the gain.

Really? Wingless tankers? What report is that?

:-)

Winglets on a Herk = tits on a bull. You take a straight-winged aircraft with a blown (STS) wing and put winglets on it, it's going to give you miniscule results. Just give us legacy guys NP2000 & we'll be outperforming the J's in no time.

Winglets on a Herk = tits on a bull. You take a straight-winged aircraft with a blown (STS) wing and put winglets on it, it's going to give you miniscule results. Just give us legacy guys NP2000 & we'll be outperforming the J's in no time.

checks.

projected to reduce cruise fuel flow by 170 lb./hr. on the C-130J

Having flown the EP-3E in a former life, I'd like to comment. This winglet mod would have to be very cheap for only saving 25 gallons an hour. But, I'm sure the reality is that it will be quite expensive and keep the airframes out of service for a good amount of time. Sounds like another DOD procurement home run... Anybody know what we pay for fuel per gallon?

The zoo did studies a couple years ago on putting winglets on the 135. The small performance improvements did not justify the cost and AMC scrapped the idea.

I like my herk looking dirty, greasy, and bad-ass. Lockheed can shove their metro gay winglets. I love their comment that winglets will save "probably more" gas like its a given, educated guess. Besides, those things will snap off after a few hundred assaults.

Out

Anybody know what we pay for fuel per gallon?

The Ops Group guy in charge of fuel for the wing said $3.90ish on base, $4.50ish at a contract location, $7.50+ in Afghanistan.

Sounds like another DOD procurement home run.

Actually, I believe its only a Lockheed proposal right now. The DoD hasn't bought any of this. They'll have to prove to both the DoD and the Congress that its a money saving option...which may be a little difficult. But, we'll see what the come up with.

As said above... NP2000's will be a much better investment than a fuckin winglet on a herk.

Time to drink! Tomorrow off cheers

I'm not sure how much $$ they'd plan on saving since we spend a lot of time at 300A...

Winglets are fine for aircraft that cruise around at altitude but down low you're gonna burn more gas regardless.

C-130NG starting in 2020, w/ new nose, tail and winglets:

https://www.flightglo...nveils-two.html

That thing isn't a Herk....

Caveat: probably what people said about the -J.

That thing isn't a Herk....

Caveat: probably what people said about the -J.

It looks like a 4 engine CASA... with winglets

And is that the crew door on the RIGHT side? it doesn't look like the escape hatch, too low...

cheers

Edited December 3, 201113 yr by Dead Last

Really? Wingless tankers?

Yep.

At least somebody out there is trying to keep Strat Airlift alive...

So we don't have to rely on Russian companies to haul our oversized stuff like is happening more an more lately.

Always

Motch

C-130NG starting in 2020, w/ new nose, tail and winglets:

https://www.flightglo...nveils-two.html

Aside from part of the fuselage and some of the wing, it looks like a completely new airplane worthy of a new MDS...doesn't really look like a Herk other than it's a 4-engine turboprop...

Yep.

I laughed

But what would happen if we bolted treadmills to the wingtips?