Aircraft - Electric - Airplanes
** Kline-Fogleman (KFm) Airfoils - Building/Flying Discussion **
** Kline-Fogleman (KFm) Airfoils - Building/Flying Discussion **
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These are the successful KFm variants developed as of November 2007 (with descriptions)
Successful KFm variants as of June 2012 (with descriptions)
The KFm1 airfoil used on the KFm Zagnutz
Taping and folding instructions - Typical KFm2 and KFm3 wings
Kline-Fogleman Airfoil Comparison Study 2-1.pdf
Step at @50% at root to @33% at the tips.
The step moved the Cg forward enough to accommodate a 6.5oz or a 4oz Lippo. Hard to believe but, AUW stayed the same due to the loss of tape!
Root end, KFm3, 1/4" x 1/2 spar, FFF foam
At least it happened before we left the yard. TGFSM
This is what happens when the place you live has 60%+ humidity year round.
Spacer thickness is in "Output" with red box around it I added to outline.
I plan to lengthen the fuselage 6" more for good stability. Fuse will be paper/glue over foam with broom-straw stiffeners underneath the paper for added strength. Wings will be white foam and tape. Main wing has an I-beam.
The bright yellow stripe is the balsa showing under the tape
Lee's Assasin shaped tips...NO FINS and it flies just great
Fuse, main wing, and front wing.
Elevator linkage is a bit convoluted but seems to work OK in testing. All adjustments made with one grub screw.
Goose look iwth the snout and moc-canopy
I still ahve a lot to do to the fuselage. I increased the length to 36" and will widen it by 1" tomorrow.
Here are the airframe details.
the Goolie a great flier available from http://www.micronradiocontrol.co.uk/
Superfly clone lines modded to the Goolish layout
The Superflys here are very close in wing shape to the Goolie so it was an easy mod to reshape the plan in Sketchup to get a Goolish look
centre layer and the two outer layers are cut
here the balsa step is visible, the total depth of the step is 9mm (1/4 balsa + 3mm depron)
bottom view ..Fuz and fins
top view ..Fins only ..no fuz on the top just velcro to hold the battery etc.
a 2 lt bottle weighs about 4.4lbs..what I should have done was to hang a bag on the end, then I could have hung a couple of bottles
No bend, and it would have taken a lot more weight. Depron wings built like this and tape covered are extreemly strong
Original, flat plate wing was too flexible in torsion. Wing would twist and aileron control would suddenly reverse.
Final KFm4 shape.
48" KFm4 Zagnutz - w/3S A123
48" KFm4 Zagnutz
Back: 160g foam fuselage. Front: 50g stick fuselage. (How much will it weigh when Gear accommodations are added???
Plain nose 1
Plain nose 2
Quite clean due to the building techniques I got from Lee's Assassin build.
just the correct size different colors are different sizes
Merry Christmas All! We start a bit early here... ;^D Me and the new bird. Hope I can tame it.
Weight is good for 3 square feet.
New Canopy is crude but the concept is good.
Doesnt' look too bad. Hope it flies OK this time.
Plane in foreground is Angel's chuck-glider. Back, L My Veloci R-Edna's Honda-Clone.
My H-D Dyna FXD
Never got this thing to balance right.
Only took a week since the day they shipped. Fast for here.
I got the receiver that came with the TX and 3 more extras too.
I numbered them. One for me and 2 for Tata
Here's the battery installation on charge. First one took about 3 hours. This one took about 20 minutes. Things are much easier the second time around
Vesper #2 ready to go.
the other side. The profile is a bit different but basically the same plane as #1
The girls together. Red in front #1. Green in back #2.
More sweep and lower AR. Hope it flies better.
This one is 36" span with 3 sq ft area and the weight all up is 475g.
Sanding shingle with 80 grit on one side and 120 on the other
Leading edge sanded round and smoothed
Needs a bracket and serious mods but it will balance OK.
800mah battery is just the right weight for this setup. I will need to recess the gear and fabricate a cam-mount that gives unimpeded frontal view while providing some protection to the camera.
"Voyager" internal structure uses 1/4" firm balsa spars, tapered towards wing tips. Filler blocks are added where floats will eventually mount directly through the wing structure
This ~9% thick RG15/KFm3 airfoil design was used for the second of the Dancer series wings.
The Komet's secondary step / filler panel is only used in the inboard 1/3 of each wing
This Komet was designed with a wing which tapers in thickness as it aproaches the narrow wing tips.
The Voyager uses a KFm3 variant lifting airfoil wing, large control surfaces. C2826 1500 Kv motor mounted
36" wingspan, 34" O.A. Length, 6.6 Oz wing loading
Voyager has 8.3% thick KFm3 variant wing, and large control surfaces. It likes speed and ignores gusty winds, yet also slows down well. Wing tip plates are very modest-sized to add stability while still minimizing drag.
Bottom has some 'visibility' tape added; single layer of Bluecor for lower fuselage acts as a landing skid for rough-field landings. Aileron outer ends are inset and guarded by wingtip structure.
First launch at the field. It was too windy but I flew anyway.
Didn't lawndart it. This is part of a cartwheel landing
Coming round for a landing at my feet.
The outer end of each Kfm4 layer is run close to ailerons at the wing tips- this build reported to benifit from taping over kf steps later
New AP plane build.
Here are 3 aircraft designed in 2009 with KF stepped discontinuities in their upper wing surfaces- Voyager, Komet, and Skyray
Blu-Guppy. Wings are 96" KFM3. Root is 9"; tip is 7 ". Wings are 3/4" thick, so thickness varies from 8.3% to 10.7%.
This picture was taken right after the maiden flight in the video.
This one is about "There". Could maybe use a bit more power but it handles the wind pretty good.
Tweaked the nose a bit too much.
So many repairs now it's getting heavy so we do a "Machete-Mod" and build another. Airframe will be sacrificed to the RC Gods!
Reworked it a little. By "little," of course, I mean completely replaced the whole front end, moved the motor mount forward by 15mm, added CF control rods, and expanded the prop slot. Minor details. You know.
Now we have to build another one!
The music makes something I enjoy even better.
Less complicated pod shape. I plan on very swept tip fins for better stability
Blue/Green/White color scheme to be different. A canard would be a nice touch too. But "Next time".
all the parts for the wing
where the zigzag will be fixed the red line is the 50% line along the wing
1st job adding reinforcing at the dihedral join..bind and fix with the required dihedral..fix using CA
the CF dihedral joint fitted between two balsa spars
overview before fitting the top skin layer
the centre section has been laminated
The tips have been fitted and gaps filled with hot melt.. now the leading edges and trailing edges are shaped
top and bottom view
This is as close to a plan as I ever get.
Hope to finish up and maybe maiden tomorrow. (12/5/09)
This is the specs generated by the measured dimensions.
Doesn't look Too bad. We'll see how she flies.
I could have done more with the fins but I wanted to finish up.
During "Crash-Damage" repairs the single fin version of Pagan has evolved.
It's almost an ounce lighter and has yet to be flown in this current configuration.
cam showing screen whist editing text
Just to give an idea what it looks like with the "Boomer" tail added. Needs repairs to wiring finishing up and cosmetics.
an extra inch on both...elevator and rudder
A simple mounting for the cam
here mounted.. make it a tight fit in the hole through the depron.. then some velcro will act as a safety strap..I think using an additional rubber band over the wedge on the backof the cam and round the nose block, might also be a good idea
Nose cover..just tape it on when cam not in use..
I have the basic shape.
Vertical fins could be more streamlined but we'll try it this way first.
The motor/prop is almost invisible with the elevator set a bit high, giving a "Jet" look
Not a bad day's work. Started at 10am and stopped at 4pm. Lazy build with lots of think time.
I believe this is the plane you're talking about.
Hard to see but the thickness of the foam is very close to 1/2". 1" Max chord thickness...
Some of the standard "forms" I use
What's left of my current stock of bottles.
Some of the parts on hand, made this way.
Starting the setup for the KFm3 VOYAGER's floats. These floats have an overall length of 24" on a 35" long fuselage; wingspan is 36"
The riser blocks will be cut to give the wing a 2.5 degree positive angle of attack, relative to the float's bottom planeing surface
Wide stance setup; interior wing structure was filled in a 1-3/8" wide area with balsa filler blocks between the 3 wing spars to provide solid attachment for the solid EPP floats which would be mounted in these locations.
doesn't look too bad.
Hope it flies OK.
Voyager's floats : top mount plate and four 1.5mm CF rods per float installed to attach these floats into the wing structure, and to transfer loads deep into the EPP foam
Four #6 x 1.25" screws run down through wing structure into each float's mount plate- easily removable when desired. Ready to fly at 22.5 ounces
Underside of wings show clean mount, no extra struts or braces needed. Float system, with 3 mil laminating film and mounting hardware adds a total of only 4.75 ounces to the VIKING's flying weight.
Voyager on floats, ready for snow flying; Works GREAT- ~30 takeoffs & landings on it's first outing, no problems at all. (Water flying delayed until we get down into AZ later this winter.)
Small EPE tip plates installed and you can just see the tape over the 2 pesos on the nose.
KFm1 or should it be a GGm1
CG shows about 11.5" I'm thinking about 11" to start.
Slot prop for balance. We'll see how it works out.
The first one looks cooler! Depends on which would give better performance. Maybe reshping the single fin???
Ready for gear installation.
Will just use elevons for now.
Maybe add rudder later when we see how it flies.
Front skid has enough room for battery to go through the wing.
Weight with motor is under 200g. Fin has rounded LE.
I made the horns from the pop bottle plastic too.
Looks OK if a bit drab at the moment.
Hope it flies OK. Should be a floater.
A little color to make it more visible in flight. (Assuming it flies???)
Canard to test feasibility of mixing full flying frontal elevator with elevons. If successful will start Double Delta based on the Druid. (Wire is 22gau for servo "Y-cables" and extensions.
"It" just happened. I'm not sure how... Anyway, "It"'s ready for Maiden.
I have no idea what I'm doing!
New frontal elevator system. Much stronger.
It's getting weird!
Final version has added a couple of ounces. She's at about 7.5oz/sq ft now.
Looks a bit more "Ship-Shape" than before, I think. Rain and wind today so no flying.
it takes a while to get the full shrink at the front but it does the job
The 36" span VOYAGER is now flying from it's floats, which mount directly into the wing structure without extra gear or struts. This KFm3 wing employs wing tip plates.
This is the wing tip plate on the upper surface; tip chord is 8". Note that ailerons do not extend all of the way to the wing tips- 1" at the end is fixed.
Lower wing surface and the extended wing tip plate; it did not have quite enough extension to work as well as desired when at <1/4" depth. Final depth below this wing is 9/16" These tip plates are now working as they should.
Can't decide on single central fin or dual. I think Dual will be easier. The frontal elevator is a transplant from the Walula.
APE... Aerial Photography Experimantal.
Factory folded leading edge on Zagnutz KFm4
Layered and sanded leading edge on Divinity 42 KFm4
After rechecking CG I had to move battery back. Canopy will cover and it looks pretty good too.
Balance point is at the mid point of the center chord.
Edna's "Whisper"... 30"WS, 7.7oz/sq ft BW powered KFm2 Canard
HatCam downloading test vid.
Not the height of fashion but should work.
Soarbird4 was chopped down to just the wing in order to do flight evaluation with it mounted on the Slim Beagle fuselage. It's a fun aerobatic glider wing, highly responsive, but has more drag than I want; wing tips may benefit from thinning.
Results after the extra two layers of Bluecor PP were carved away from the upswept portion of the wing tips. The improvement in both glide efficiency and flight stability are nothing short of amazing!
C/G without battery. Glides like this. Huh?
Simple electronics package underneath along with some bamboo to keep the fuse together.
simple dihedral less, than the usual Nutball tip dihedral, but enough for some stability. Elevons and rudder for control
Fubar, my first "big" KF wing. She flew very well and was a nice slow starter plane.
Edited kfm7 image file
just an adjustable strip of velcro through the clip, and some depron to wedge the thing at the correct angle to my forehead.. follow the plane with your head eyes front and the results are very good
New Whisper MK3. Hope to maiden it tomorrow.
Touch the two wires together to change mode. Will try to find an old bad piece of electronics to rob a small NOPB switch.
Takes pictures and video. Not great quality but a nice new toy to play with.
broken down. The PenCam has a replaceable ink cartridge, 2G mem-card built in and simple controls from one switch on top of the pen. It could be flown just using the upper half. The lens is just above the top of the pocket clip.
KFm4 SpaFFFnutz wing tip
heres a partial construction pic ..theres more ribs to go in and the other side would be the same,, but I am sure you get what I mean.. The whole wing would be mylar covered
Whisper MK4 Interchangeable canards for easy experimenting.
Coroplast flute cutters - Do It Yourself model
This was the original idea.
I'll leave the nose long for now so I can put the canard back if I want to.
Definitely not a canard anymore... ;^D
This, as yet, unnamed pusher boomed cat is an attempt at a floaty and acrobatic small field flier.
No armor in an attempt t keep it light.
I don't believe I'm building this retro looking bird...
Not sure I like the P-51 type tail but I may round things off as it comes together.
Just a simple full house approach.
flat cut out along the spline.. position to have the rear wheels of the trike back a couple of inches from the COG
Ply plate 2" wide waiting forthe two velcro strips
No name JAP
My feelings are totally ambivalent towards this thing.
Original "Double Finned" Mock-up.
Where we are now! Subject to change dependent on "Whimsy"... CG is a bit before the front of the slot and I may change the fin shape and add a front battery pod for balance if needed.
Weighed like this I get 400g and the wing area without a canard is 375 so it's under 6oz/sq ft. Not sure how it will be when finished and when the servos are mounted I'll re-check balance.
Ready to maiden with smalll canard for balance
30's racers based off Parkflyer Pete: Red Pete, PV2, Mike
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