UFO- Useless Flying Object

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BJC

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I was thinking more along the lines of a wing incidence handle (like an old Cessna flap handle). You could crank in 20 degrees of incidence on final. That way you could take advantage of the high AoA of the wing, still be able to see the runway and you wouldn't need super long gear legs.
A la the F-8, and its baby brother, the A-7.

BTW, slotted flaps can be used to effectively increase the AoA more than plain flaps, thus improving the pilot's forward vision on approach. Two other advantages, from my point of view; they increase Clmax, and the wing is rigidly attached to the thing the pilot sits in.


BJC
 

FritzW

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Nemeth used two different flap/aileron configurations. There must have been something on the first wing that he thought was worth improving.

Nem_Parasol_SM-850x454.jpg Nemeth-Parasol_3.jpg
 

rotax618

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Hoffman found that the elevator on the later Arup lost effectiveness because it was in turbulent air being behind a very wide chord wing, his cure was to place a small tailplane/elevator high on the fin.

There is a modification to the Dyke Delta to place a small pitch control surface up on the fin.

Zimmerman had horizontal tail surfaces projecting from the sides of the Fuselage/wing on the Flapjack.

Note the very large elevators/elevons on both the UFO and the Verhees Delta, these are necessary because the control surfaces are operating in turbulent "dead" air, because of their size and weight they would be prone to oscillations in turbulent air.

The answer for this problem in low aspect flying wings is to use "Junkers" elevons (hanging below the wing they would be prone to damage), or place a pitch control surface on the fin (as per Arup3 and Dyke Delta) or place the control surfaces at the wingtips (per Zimmerman)
 

FritzW

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I have his phone number.
Does someone wanna put together a "shopping list" of information requests, and I can call him?
Thunderchook,

Are you still in touch with David Rowe? I'd sure like to know what airfoil he's using on his UFO's.

Looking at the videos I'm not seeing much, if any, reflex.

Thanks,
Fritz
 
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BJC

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Just to set the record straight, while the F-8 had a variable incidence wing, the A-7 did not.
Yes, you are correct.

Am I correct in thinking that the A-7 used the same wing attach method, with a rigid link tying the forward attach to the fuselage, rather than an actuator, and having an aft attachment that was capable of pivoting?

Did you work on them or fly them?


BJC
 

Angusnofangus

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Yes, you are correct.

Am I correct in thinking that the A-7 used the same wing attach method, with a rigid link tying the forward attach to the fuselage, rather than an actuator, and having an aft attachment that was capable of pivoting?

Did you work on them or fly them?


BJC
I don't know how the A-7 wing attached, but I suspect it was conventional. Didn't work on either airplane, but worked around them. The only real similarities between the two was the basic layout. A-7 was a flying dump truck, carried a lot of bombs, F-8 had provisions to attach pylons and carry bombs, but I don't think they were ever used in combat. If I am wrong on that, someone please correct me.
 

mcrae0104

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BJC
[video=youtube_share;gJV16xYPVtA]https://youtu.be/gJV16xYPVtA[/video]
 

billyvray

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I cropped this pic from an Australian magazine Australian Sport Pilot, on Issuu.com. Check it out.

I have long wanted to see how Mr. Rowe had constructed his UFOs. It is easy enough to conceive but I just like to see the particulars. Anyway, I hope it brings some enjoyment and education...

rowe ufo sport pilot mag.png
 

Aesquire

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The A-7U wings were "simply" bolted on.

The F-8U did carry bombs, up to 2000 lbs. Plus 5" Zuni missiles, and was used as a bomber. Arguably long predating the F/ A -18 as a dual purpose fighter bomber... But so was the Corsair. And the Wikdcat. And...
 

BJC

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Photo of A-7 forward wing attach fuselage fitting. There is a dog bone shaped link between this fitting and a fitting on the LE of the wing center section. There is room for jackscrew to replace the link.
IMG_1033.JPG
Here is the rear fuselage attach fitting. The attach pin would allow the LE of the wing to rotate up, even though the A-7 does not use that feature. I believe that the F-8 uses the exact same main wing attach.
IMG_1034.JPG


BJC
 

RCBinChicken

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I cropped this pic from an Australian magazine Australian Sport Pilot, on Issuu.com. Check it out.

I have long wanted to see how Mr. Rowe had constructed his UFOs. It is easy enough to conceive but I just like to see the particulars. Anyway, I hope it brings some enjoyment and education...

View attachment 84909
Thanks so much for finding and posting this, it's a gold-mine for me... Another few hours on this forum and I find ANOTHER design I never knew existed, that makes my own pipe-dream low-AR aircraft seem so much more plausible than I dared expect! The shot of the wooden interior construction is beautiful. What's even more beautiful IMO is the name, and the "screw it, this is the plane I WANTED to build" attitude of the designer.

I hurriedly googled it for more info, here's a couple of other links if anyone here hasn't already seen them:
http://atsconsultancy.com.au/demo/Aeropidia_info/rowe-ufo/
https://www.airliners.net/photo/Untitled/Rowe-UFO-Useless-Flying-Object/2811274

Alright, a 4m wingspan, (pi*d^2)/4 gives around 12.56m^2 wing area... The second link quotes 145kg dry weight, of which around 35-42kg presumably is the Rotax 503 and its exhaust system. So around 100-110kg for the airframe sans powerplant. Even if we assume Mr. Rowe is a heavily-built chap, that's looking like a pretty low wing loading. Not bad for an aircraft you could fit, fully assembled, in an average living-room.

Now I just need to figure out (from my vast, entirely nonexistant personal expertise!) how to build a similar craft with closer to 17m^2 WA, HALF that airframe weight figure and shaped like a triangle instead of a circle. :p
 
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