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Posted by RPM314 | Dec 14, 2014 @ 04:20 PM | 1,582 Views
Not a replacement for the Mk.V or necessarily a better machine, just designed for a different job. FPV, BABY.
That's right, Imma get me some FPV gear by year's end. To accommodate it, I'm making a 54" (1370mm) wing with a turnigy d2838/8 (1100Kv) motor with a 9x6. I want to make a simpler kind of craft that is a bit more easily replaceable should it get lost out somewhere. I'll also probably set up a parallel harness for batteries to get some more duration. Lots of wing area, lots of power, lots of battery capacity, a thick wing root, and a beefy motor means a floaty, heavy lift, long duration, stable FPV platform. Hopefully. We'll see how that turns out.
I also want to make it foldable to take in the car on vacation and surf down the Appalachians or something, get some nice cliff diving videos and such. That presents the challenge of making a removable motor mount, and I believe I have an adequate solution, but of course that will still be trial and error.

12/13: All foam pieces are cut out, fins are taped up and ready to go, the wings are taped up and scored for folding, the formers are glued together. Note - use reinforcement tape at the LE under the packing tape to provide tensile strength so the foam doesn't crack, that has SIMILAR ADHESIVE PROPERTIES to the packing tape. I used cheap duct tape that slides a bit more easily, and messed it up something awful.
Posted by RPM314 | Dec 02, 2014 @ 06:33 AM | 1,303 Views
A little late on the processing, but here's a couple more:

Some nice air video spliced with ground video courtesy of Mark, it looks really cool.

Falcon Mk.V - Thrill Factor (6 min 8 sec)


A compilation of 3 flights from Peter's HawkSky, managed to get a little ground footage in there.

...Continue Reading
Posted by RPM314 | Nov 17, 2014 @ 08:01 PM | 1,410 Views
Just sporty flying in the Falcon, no boooring gliding around. Carving low passes, low down straight runway shots, loops, inversions, dives, twists, and AC/DC.

Falcon Mk.V - Right to the top (6 min 17 sec)

Posted by RPM314 | Nov 17, 2014 @ 07:59 PM | 1,396 Views
Some more of my wingman Peter flying his Dynam Hawksky around the field, climbing and diving around.

Peter's HawkSky - Pushing It (3 min 39 sec)

Posted by RPM314 | Nov 15, 2014 @ 11:20 PM | 1,607 Views
I binge watched Free Bird by Lynyrd Skynyrd so I could sync the flight to the song. This is the Falcon Mk.V with Peter's Mobius action cam (wide angle lens) stuck into the right air intake, and shows the plane's amazing ability as both a motorglider and a pylon racer. Some good climb and glide segments, then 5 minutes of carving sweeps around the field, low passes, and lots of loops and stuff.
This was filmed on 11/15/14 at the Remote Control Society of Marine Park, it was one of those days where it is cold but the air is perfectly clear, so the high altitude video is stunning. There is another video from that day, I should have it processed by tomorrow.

Falcon Mk.V - Free as a Bird (10 min 51 sec)

Posted by RPM314 | Nov 04, 2014 @ 07:36 PM | 2,065 Views
Hi, all. Made a cutting edge, super lightweight, crash resistant mounting system for future mobuis action cam flights. This is some real next level stuff, super streamlined and engineered for VICTORY. The world has never seen nor will ever see again this degree of prescision....
Ok it's a mobius shaped box with tape covering. It has little spacers inside so it doesn't push the buttons. The top panel comes off so you can put the camera in it. It's made of foam. That's about it.
Posted by RPM314 | Oct 30, 2014 @ 09:13 PM | 1,732 Views
Flying at RCSMP in October. My wingman Peter McGyvered a Mobius action cam to his old HawkSky and gives us a good view of the field. The Falcon Mk. V also makes a few guest appearances.


HawkSky with onboard Mobius at RCSMP (3 min 54 sec)

Posted by RPM314 | Oct 18, 2014 @ 06:37 PM | 1,434 Views
The Buzzard's motor has been rendered inoperable because of its tractor configuration and proximity to the ground upon landing (read: front motor dun got messed up when I landed). The new aircraft using the 2s power system will be something I have wanted to try for a while; a slightly forward swept flying wing with strakes. It will have a small fuselage pod and twin vertical fins, pusher prop, and a 4-flap wing ('cuz I have way too many 5g servos to use). I might try out 7x6 props on it instead of 8x4's, since this should be more controllable at high speeds than the Buzzard.
When drawing it out in sketchup, I figured I couldn't move the fins back far enough behind the CG for them to be super effective, so I thought I might need rudders on it to stay coordinated. Then I thought only needs 1 servo+makes use of ability to spin out+also gives yaw control=THRUST VECTORING YAW. So I'm going to try my hand at making a hinging motor mount.

10/19: All parts are cut out, but nothing is taped. Spars are embedded in the wing and the KF steps are in place.
10/21: Flaps are beveled, and I made a torsion bar for the elevators.
10/24: Control surfaces and the wing are taped up, the fuse sides are glued in and the fuse bottom is attached to those. All servos are glued in place and connections to the Rx are hooked up.
10/26: Elevators are connected, the TV yaw block is constructed, the top wall of the fuse is shaped to accommodate all the stuff under it
11/2: The fuse top is installed,...Continue Reading
Posted by RPM314 | May 26, 2014 @ 10:47 PM | 2,070 Views
Note to self-think of better name for airboat than "Airboat"
Done- "Drake", a male duck (waterfowl-get it? yeah).

Same hull design as the last one, but this time it is made of MPF. The fins at the back will also be higher to capture more of the propwash with the rudders.

5/26: Frame and lower hull are complete.
6/19: rudders are done, the motor is mounted, and the deck is on. The receivers arrived, so this ship is ready to sail.
6/29: Wind flipped it over, will dry the parts out overnight. If the ESC still works, I will try it in the Falcon mk.V to see if it gets it working.
6/30: ESC still works

Status: Gutted for parts
Posted by RPM314 | May 11, 2014 @ 08:23 PM | 3,429 Views
My take on the FnF, which is a variation of the Funbat, which is based on.... You get the idea. 32" span, KFm2 airfoil, 1700Kv BW motor, 10A ESC, and 950mAh 2 cell battery. I hope to fly streamer combat with it against other guys at the field.
This is a quick and dirty build, without much attention to detail. In fact, I believe I will be able to complete it without sanding anything, which is a relief after all the shaped wingtips on the Falcon craft.

Finally, some progress to report. I finally got the wing to cooperate, it is folded over to make the step neatly now.

5/24: PARTS, GLORIOUS PARTS. A whole bunch of 2s stuff came in from strongrcmotors.com, and I am ready to build. Servos are glued in, components are aligned to balance the thing properly, and the ESC has a little cooling window in the side of the fuse to peek out of. Still need some receivers, and some very small screws to mount the motor.

5/26: The ship is as far along as it will get without the receiver: once I order those I can attach the fuse.

6/19: The receivers arrived (FINALLY), so the fuse is now attached, the control linkages are set up, and this bird is ready to fly.

6/29: Maiden went well, it handles the wind nicely. It handles very well, responsive yet floaty. I need to rebuild the motor mount and resolder a motor lead, though.

7/2: Repairs are complete, it is ready to go again.

7/12: Flew it in real streamer combat, it is excellent at the sport.

Status:...Continue Reading
Posted by RPM314 | Mar 22, 2014 @ 12:20 AM | 2,672 Views
Given that the structural insufficiency of MPF in the glider type wings renders the fuselage pod useless, and that I slammed the Mk.IV into blacktop pretty hard, I am making a new bird that gets back to the roots: a pure, solid wing. No bells and whistles in the layout, it will consist of a swept, tapered wing with washout, with small laminated wingtips and solid fins, and a hatch in the center. There will also be vortex generators near the wingtips, and the gear from the Mk.IV will be transferred over.
3/22: All parts are cut out, the wings are taped up and have the formers, but do not have the full compliment of carbon or the servos. Lots of sanding and taping still need to be done.
3/26: The interior of the wings are done, the fins and elevons have been sanded, and sanding has begun on the wingtips.All those parts still need to be taped over before they can be installed.
3/28: The wings are closed up and washed out and the wingtips and fins are finished and attached.
3/30: Elevons are finished and attached, ventilation has been taken care of and a battery hatch has been installed.
4/2: Motor mount is complete, but I will not mount the motor until everything else is done so I can use it to balance the plane.
4/5: Elevons now have 1/16" balsa on the underside for stiffness. Control linkages are set up and functioning, the plane is balanced at 10% MAC, the motor is mounted, stripes are on the bottom of the wingtips, and the vortex generators are in place. All...Continue Reading
Posted by RPM314 | Feb 23, 2014 @ 05:52 PM | 2,399 Views
Hi, all. After ealizing that the gear from the Petrel was lying around being useless, I cobbled together a quick 24" wing from MPF.
The root chord is 6.25", the tip chord it 4.25", and the sweep distance is 6", with a kfm2 airfoil. It has 2 5g servos directly linked to the elevons (no pushrods), a 3A turnigy UBEC (smallest one I had), an orangerx 610 (I think) and a 2s 280mAh lipo battery. AUW is about 2oz, which is a bit heavy. It needs to be scaled up to about 30" or 36" to really float, but as is it would make a good sloper if I had a place to slope.
The maiden was today, and it flies nicely, if a bit fast for a glider. I rigged a rubber bad to hook into my friend's plane's cargo bay door, so the plane was carried on its underside. When the door was opened, the end of the rubber band came loose and the glider was released. Big cheers from all over the flying field.

Status: Cannibalized
Posted by RPM314 | Feb 17, 2014 @ 07:03 PM | 2,974 Views
Hi, all. I decided to take a crack at the hydrofoam, with my own twist of course. It will be made of MPF, colored packing tape, foam tac, and some hot glue. For the electronics, there will be an AR610 receiver, MG90S servos x3, HK 30A ESC, turnigy D2826-10 motor (1400Kv) swinging an 8x4 prop, and 3s 2200mAh batteries. I call it "Raider" because of the front halve's resemblence to a Cylon Raider fro Battlestar Galactica.
It is pretty similar to the design found at Parkjets.com, although I did not intend to make the dimensions as similar as they are. The main difference is that the prop is mounted on the tail like an airboat instead of on a pylon over the ventral pod. I did this to avoid ground and water strikes more, and because I could not come up with a ventral mounting system that did not look like garbage.
Overall length is 26", overall width is 16". There is about 1.5 square feet of lifting area, and I expect AUW to be around 16oz. It will not be 3D, but it will still be very sporty. With only red and black tape to work with, I believe I came up with a neat trim scheme, yes?
If anyone wants to reproduce it, reply to this post and I can send you the complete model and parts template.

2/18: Airframe awaits final assembly and fitting of gear.
2/19: The Rx recovered from the lightning is busted after all, so I pulled the one from the falcon for the job. The plane is complete!
2/23: Tried to fly it today, no such luck. It feels nose heavy on the...Continue Reading
Posted by RPM314 | Dec 30, 2013 @ 06:38 PM | 2,597 Views
The next iteration of the Falcon is very different from the previous ones mainly in that it is made of MPF instead of dollar tree foam. It also incorporates the wingtips from the Lightning and a similar trim scheme. There is also 3 degrees of washout to fight tip stalling, which was a serious problem on the previous models, and the wings have a taper ratio of about 2/3. Power is a Turnigy 2826-06, 2200mAh battery, and a 30A HK ESC. There are two sets of wings, a sporty and glider one, which plug into the fuselage instead of being strapped on top. As such, the wing halves are kept separate instead of hinged.

12/30: Plans are drawn out on the foam.
12/31: Parts are cut out, the sport wing has been tape covered and the spacer attached.
1/1: One of the sport wings is nearly finished, needing only a control linkage.
1/3: Glider wings are up to the servo installation stage, and the fuselage tube is ready to install equipment in.
1/5: Both sets of wings are complete and the electronics are dry fitted into the fuselage for balance testing.
1/9: The correct mounting points have been identified, still working on the actual mounting.
1/11: Mounting is done, fuselage is completed, control linkages are complete, and system check have been run. This bird is now ready do fly, maiden will most likely be this Monday.
1/20: The weather forecasters were highly inaccurate about the wind speeds, they said 12 mph and it was really twice that. The glider wing is dented and the mounting tabs must...Continue Reading
Posted by RPM314 | Aug 31, 2013 @ 10:50 AM | 3,356 Views
The cheesily named Greased Lightning will be derived from the Polaris, with a few important changes. First, it will not be a seaplane since I do not fly off of water, so some design elements regarding waterproofing can be left out for simplicity. It will still be able to taxi/take off/land on land though. Second, it will be much more efficient. The Polaris also had a low aspect ratio flat plate wing. It is simple and good for extreme high alpha and whatnot, but it is not very efficient. Cut the power and it drops like a rock, take a sharp turn and you lose half your speed. GL will have an armin airfoil wing of about 10% thickness (very thin) with large strakes to preserve the high alpha ability of the original polaris. The aspect ratio will be about 6, so it will glide well and keep speed in turns. Power will be a turnigy d2826-06 spinning a 6x4 and a 25A esc. Wingspan is 42" (~105cm) and length is 33" (~84cm).

Here are the dimensions for anyone who wants to replicate it:
The wing is made by taking a 30" section of 5" chord armin wing and cutting it in half to create 2 15" sections. These are swept 15 degrees at the root only, the tips are kept square. The wingtips are quarter circles with a radius of 6.5". The ailerons have a chord of 1.5". The strakes are triangles extending 6.5" forward and 6.5" along the leading edge of the wing. It is formed from 2 opposed trianlges with a rectangular area 1/2" wide between them (...Continue Reading
Posted by RPM314 | Aug 12, 2013 @ 09:53 PM | 3,595 Views
A 48" (1.2m) glider made of DTFB as usual. Gear is an AR600, a turnigy 3A BEC, a 280mAh 2s lipo, and 5g carbon gears. It also has an on/off switch (Fancy!) It is of conventional layout with flaperons.
The wing has 2x 20" sections of armin wing with a 4.5" chord. Wingtips are 4 layers of laminated foam sanded down to shape, with a 4" span each. Flaperons are 2" at the root and 1 1/8" at the tip, extending from the elliptical wingtips to 1" from the fuselage. It has a 5/16" wooden main spar of 42" span, a 32" span 3mm carbon spar near the top of the wing (since the top tends to compress under load), and a 16" span carbon spar near the bottom.
The horizontal stab is 13" in span, has a root chord of 4 3/4" and a tip chord of 3 1/4". The vertical stab is 6" high, has a root chord of 4 3/4" and a tip chord of 2 1/4". It also has a 45 degree bevel to allow for elevator travel. Both have a straight trailing edge. The elevator has a chord of 1 1/4". The rudder has a root chord of 1 7/8" and a tip chord of 1 1/8". Both have aerodynamic balances extending 7/8" forward and are 7/8" wide. Each has a 3mm carbon spar and they are affixed to each other by a plastic gift card bent at a right angle, mounted internally.The assembly is hot glued to the fuselage such that the elevator hinge line is at the end of the fuselage.
The fuselage is a 40" long square tube (composed of...Continue Reading
Posted by RPM314 | Jul 01, 2013 @ 06:18 PM | 2,865 Views
I plan to make another Polaris, but I do not have the resources necessary at the moment. I do have the parts for the boat necessary to run it off of water, though.
It is made of $ tree foam and put together with mostly foam-tac and some hot glue. The foam tac is especially useful for sealing the edges of the foam to keep water from making the paper peel off.
The hull outline is from Alex Tretter, the rest is me. Power is a 1300 3s lipo and a turnigy 2826-10 on a 8x4. It was a quick build, and has only been tested indoors so far.
It has a light ply hard point at the stern to attach a string with which planes can be pulled back to shore.

7/2/13: Maiden voyage on water, mulch, asphalt and astroturf. Please be aware that foam-tac is somewhat less effective at waterproofing once it has been worn away by hard surfaces. The bottom of the hull is now structurally compromised and must be replaced/extensively repaired.

For the life of me I cannot get the hull waterproofed. The paper always gets wet and peels off the foam, compromising the structure.

Status: Decommissioned for parts.
Posted by RPM314 | Jun 06, 2013 @ 09:28 PM | 3,076 Views
I have just ordered a ludicrously large BEC, and will rebuild the airframe. Just a few minor adjustments to the mk. 2. The fins will now be completely removable, because I have found that folding them under the wing creates storage and construction problems. This will allow the fins to extend below the wing to act as skids. The 25" section wing will now be included, as well as a 40" section wing. They will all have 1/8" wooden dowels embedded in the foam for strength. Also, the rear 1/4 of the fuselage pod will be removable to switch motors easily. I now have a turnigy 2826-10 for the larger wings. Because of this, all the wings will have an 8" prop slot instead of a 6".
All the wings, from largest to smallest, have wingspans of 29.5"(725mm), 42.5"(1040mm), 54.25"(1330mm), and 75.75"(1855mm). The sweep angles are 30, 22.5, 17.5, and 13 degrees respectively. This makes all the wings have the same sweep distance, and so the same CG.

6/7/13: all wings are up to the angle cut stage, and 2 of them have spars.

6/9/13: All wings have spars and control surfaces, the fins are as far along as possible without complete wings, and the fuselage is as far along as possible without the new parts. It only needs to be closed up and tapered at the nose.

6/10/13: All servos are set in the wings. Waiting for parts to progress further.

6/13/13: Parts have arrived, construction will resume tomorrow.

6/15/13: Done! Maiden will hopefully be on the...Continue Reading
Posted by RPM314 | May 23, 2013 @ 08:47 PM | 3,175 Views
This is essentially an improvement on and replacement for the Dart (now falcon mk. 1), the one lost on the island. It will have 3 wings this time, and a wider fuse pod. The 3 wings will be made from sweeping 20", 25", and 30" sections of 5" chord armin wing 17.5, 22.5, and 30 degrees, respectively. This puts the CG in almost the exact same place, eliminating the need to shift the battery. It also makes the speedier wings have a thinner effective airfoil, and the floatier wings have a lower sink rate.
It will be made of dollar tree foam board (redi-board by R.L Adams), abbreviated DTFB for the purpose of this entry, colored packing tape and foam-tac. The pictures below are of the 20" wing, the other wings being constructed the same way.
Please refer to Ed's thread in the scratchbuild forum, it tells the whole story of this construction method.

Edit (5/26/13) - 25" wing is on hold due to a miscalculation of parts quantity.
It is powered by a Grayson supersonic v2, and 40A ESC as usual. Using 1300, 1600, and 2200 3s batteries, and an orange rx. One problem with this design - due to CG constraints, the wing must be located right over the battery hatch. On the plus side, the hatch will never come off in flight. Still a hassle, though. Maiden will hopefully be tomorrow.

Status: crashed due to brownout. Will rebuild, possibly with more wing options....Continue Reading
Posted by RPM314 | Mar 28, 2013 @ 10:39 AM | 3,494 Views
Finally, after 3 months of nonstop technical difficulty (with a brief respite by the Polaris), this bird is finally airworthy. It is made of dollar tree foam board and colored packing tape using Experimental Airlines building methods.
The fuselage pod is 2" external diameter, which is a very tight squeeze, and 20" long. It is tapered down at the nose and up at the tail, and the bottom has clear acetate to toughen it up for landing. There are popcicle sticks going through the pod for wing tie downs
The wing system I am very proud of. It has two interchangeable wings. Both are 5" airfoil chord armin wings swept 22.5 degrees, but one is made from sweeping 30" sections and one is from 20" sections. So, there is a 33" and a 49" span wing for this plane. The 33" is a solid piece, and the 49" is in two halves with folding vertical stabs. When you take the spar out, it can be used to lock the two wing pieces together. The result is very compact. Both are secured to the pod with rubber bands.
I am using the same gear as always, GH supersonic on a 6x4 with a 2200 or 1600 3S. With the 2200 full forward, it balances on the 33", and full aft it balances the 49". AUW with the 2200 and 49" is about 20 oz, given the thrust to weight, and has a wing loading of a mere 8.4 oz/sq. foot! Should be a blast, pics coming soon.
Did the maiden. Word of warning: this calculator lies. It put the CG about an inch behind where it should be. The 33" just plain didn't work, and the 49" barely survived.
All fixed. As expected, the 33" is speedy and agile, and the 49" glides like a dream, gave a Calypso a run for its money.

Status: Completely intact, blown out of range, inaccessible, on an island.
Now gone, floating around in NY bay somewhere.

Edit: has been retroactively renamed