Leeham News and Analysis
There's more to real news than a news release.
There's more to real news than a news release.
Leeham News and Analysis
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KC-46A refueling boom, drogue testing
Oct. 13. 2015: The US Air Force and Boeing released photos of the KC-46A aerial refueling tanker with the boom and the drogue deployed. Photos by John D. Parker. Click on images to enlarge.
What is that little “prompters box” on the tail cone ? Tail gunner ;-?
Flight test instrumentation most likely.
probably a threat detection system, like a radar warning receiver or some such
Box for a drag chute ??? therefore no need of thrust reverser !!!
definitely a tail gunner. Probably laser weaponry from the lack of protruding barrels
then again, maybe it’s for taking selfies of the refueling pilot so they can keep their hands on the stick?
😉
Looks good!
Might look like basic tests but remembering the KC767 and MRTT test periods, lots of dynamics involved. Flutter, the FBW of the boom, boom stability in the slipstream.. The Kc767 no doubt provides a good list of “don’ts” being incorporated in the design.
Hmmm. No thrust reversers ?
No thrust reversers. See, this is a “cheap” product.
Its a pity , the PW engines on the C17, the thrust reversers can back up the plane up a slight slope.
Thrust reverser were not desired by AF.
Good or bad Boeing is giving them what they asked for k
Needs some 787 style wingtips.
???
Why do you think that?
What does that have to do with refuelling?
Save some fuel and save some money. I’ll be surprised if the Air Force buys more than 100 of these without a new engine. Pratt should start work on a 40K to 60K geared turbofan for new commercial aircraft and the KC-46.
Note that the original KC767 had issues out there with the drogues system
Dreamlifter had them removed.
May shoot yourself in the foot so maybe they know what they are doing for a tanker
How can you tell what wingtip shape is, from that dark photo?
(Note that different wing designs have different needs and design approaches. Boeing has tended to favour a “raked” tip, which they introduced on the 767-400.
http://www.aerospaceweb.org/question/aerodynamics/q0148.shtml
Same used on 787.
And there may be a need for special antennas or pods on wingtips, which may change the aerodynamics – for example http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104537/kc-46a-tanker.aspx.
And a better view of the small tip pods:
http://www.cobham.com/about-cobham/mission-systems/air-to-air-refuelling/products-and-services/hose-and-drogue-systems/wing-air-refuelling-pods/kc-46-refuelling-systems-datasheet.aspx.
Some illustrations/photos do not show the little pods. So you can’t depend on any illustration/photo. Perhaps the design is evolving, including by customer additions or finding that other locations for sensors/antennas don’t work as well.
Note as well that the refueling pods are well outboard, presumably to maximize spacing between aircraft receiving fuel. I’d want to ask aerodynamics experts if that affects choices of tip shape, as the refuelling pods will have a significant effect on air pressure in the area
and are a significant blockage to spanwise flow which creates the tip vortices that tip shapes and winglets try to reduce.
Nice pictures. Hopefully we will see even better ones in the near future.
“This tanker will be able to refuel any fixed wing aircraft or helicopter in the DoD fleet, while being able to take on fuel itself.”
– Col. Christopher Coombs
http://www.defensenews.com/story/defense/air-space/air-force/2015/10/12/boeings-tanker-deploys-aerial-refueling-systems/73816446/
I can’t wait for pictures of the KC-46 refueling a CH-47 or an MH-60!
Well, we’d have to compare low speeds (this being an airliner with reasonable airfield performance) and test airflow for receiving aircraft with flaps fully extended.
I have seen claims that the V-22 can keep up with the Kc-46.
As for being able to receive fuel itself, that increases versatility – at some cost of weight and fabrication – by being able to be topped up by another tanker during long-range escort missions such as of a bomber. (Today the DC-10 tanker does the long bomber missions.) Another tanker can rise up from an enroute base to refuel the escort tanker.
Having worked with B737, B767, and C-130 performance, I don’t recall the C-130 being an especially slow airplane – I considered it sizeable and fast just like the 737. (But with LP tires, big cargo bay cross-section, and rear loading door.)
I get the skepticism about the capability to refuel helos. I’d still love to see the pics if it ever does happen. Perhaps having the -300F wing and the -400ER high lift systems on the -200ER fuselage will help with matching the speed of slower aircraft.
Exercised Google a bit.
Only Helo refueling (non CGI 😉 images I could find show Hercules based tankers doing their thing.
( and some experimental V-22 project refueling a F/A-18 Hornet.
http://amarillo.com/news/local-news/2013-10-03/bell-tests-v-22-osprey-new-role )
probably not as simple as it looks 🙂
Of course, but that’s not the same as impossible or even unlikely. Perhaps the Col. misspoke. I hope not.
As for helicopter speed re refueling- I seem to recall a CH being able to fly fast enough to dangle Charles Heston in front of a fully loaded 747 being flown by a flight attendant … so refueling one from a 767 should be no problem :-PPP