ELECTRIC R/C
SAILPLANE CATALOG

A man and hist Electric Sailplane
Tom Tock and his beautiful converted OLY III

Wood Crafters #8 Six Minute Task Audio Program

Electric Motor Size and equipment Tool - Use this Tool link to determine motor, prop, and battery size, escapement. AXI motor, propeller, speed controller, Li-pols or NiCd.

Props and Spinners

http://www.maxxprod.com/mpi/mpi-11.html

Tower Hobbies Units of Measurement Conversion Calculator:
http://www.towerhobbies.com/help/convcalcs.html

Horizon Hobbies Electric Motor info pages from their web site:

Park 480 Brushless Outrunner Motor
Power 10 Brushless Outrunner Motor
Park 450 Brushless Outrunner Motor
Power 15 Brushless Outrunner Motor
Power 25 BL Outrunner Motor
Six-Series Brushless Motor

Tower Hobbies Electric Motor info pages from their web site:

Great Planes Rimfire 400 28-30-950 Outrunner Brushless
Great Planes Rimfire .10 35-30-1250 Outrunner Brushless
Great Planes Rimfire .15 35-36-1200 Outrunner Brushless
Great Planes Rimfire .25 42-40-1000 Outrunner Brushless

Gear drive (link)

Ammo motor chart relating watts to Sailplane Flying weight:

Ammo motorwattsMax-Sailplane flying weight
based on 80 watts per pound.
28-45-3600592118 oz - motor weight 4.6oz
28-45-2700518103 oz - motor weight 4.6oz
24-45-379027855 oz  - motor weight 3.6oz
24-33-318019038 oz  - motor weight 2.4oz
20-40-350013326 oz  - motor weight 2.3oz

Great Planes Ammo 20-40-3500 In-Runner Brushless Motor
Great Planes Ammo 24-33-3180 In-Runner Brushless Motor
Great Planes Ammo 24-45-3790 In-Runner Brushless Motor
Great Planes Ammo 28-45-2700 In-Runner Brushless Motor
Great Planes Ammo 28-45-3600 In-Runner Brushless Motor

KITS

All the Sky Bench kits can be converted with an electric motor for launching. Some of the kits have specific parts for motor mounting, others are conversions by the builder.

If you mark the order form or make a note on your facsimile order that you are installing an electric motor, the kit will contain triangle wood stock to be used in shaping the fuse nose section round to conform the the motor/prop spinner shape. Also, the front fuse sides will be balsa instead of plywood to save weight in the OLY and Bird Series kits. ... See the 2M E Lil Bird parts photo for reference.

Due to the light weight motor and battery, most of the kits will balance with the battery located behind the motor and the motor controller, servos and Rx behind the battery. The motor can be mounted outside of the fuse, this will allow the best cooling to the motor and easiest conversion. Remember to make provisions for cooling the motor controller and battery. The 3014 airfoil is an excellent all weather airfoil for electric powered Sailplanes.

A word of caution. Check the prop for cracking at the base of the blades before each flight. I have received reports from customers of a prop blade flying off at launching.


1.5m Osprey on fence, Click here for larger picture. 1.5m Osprey on bench, Click here for larger picture. 1.5m Osprey on grass, Click here for larger picture.

OSPREY

Bill Jones and his Oly3
Bill Jones launching his Oly3 Bill Jones electric Oly3 on flyby

Love my electric OLY 3

Hi Ray, I have just test flown my new Oly 3 that I built these past few months. Attached are a couple of photos of its first flight. Thank you for assembling and selling such a good kit. The build was very satisfying and the quality was excellent.

I electrified the plane, using a NeuMotor 1110/2Y motor with a 4.4:1 gearbox and a 15X10 Cam carbon folding prop. It has a Phoenix 50 Ice Lite speed controller with a separate 5 amp BEC and uses a Thunder Power 3-cell, 45C, 2700 mAh Lipo battery. Flaps were used instead of spoilers to provide the option of camber change as well as landing control. Mixing a little down elevator with the infinitely variable flaps (on the throttle stick of an Airtronics SD-10G radio) has worked very well. Total flying weight came in at 75 oz. and the motor is drawing 376 watts, resulting in 80 watts/pound. At just over half throttle the plane climbs very briskly and at a very steep angle….it definitely does not need any additional power. On its maiden flight I took it to about 300 feet and killed the power…….15 minutes later it had no intention of coming down and was coaxed down with flaps. There is a cooling air inlet through the turbo spinner into the fuselage, but no intentional air exit holes, yet the speed control is running at 125 degree F., well below the temp. max. for the electronics. This plane is a dream to fly and I am now planning my next SkyBench build.

Thank you for your excellent kit. Best wishes.
Bill Jones.
Kelowna, BC, Canada


Frank and Larry with their elect oly IIIs

OLY III, more fun by the pair

Ray,

Just had to let you know how much we love this plane! Larry and I put the Olys up on Sunday and this plane just floats forever! We have Ammo 28-45-2100 brushless motors with 4.3-1 planetaries with 16-10 folders on them. Only took about a 20 sec. climb to get to 500ft. and mother nature provided the rest of the lift. After a 30 min. and 45 min. flight we decided that this is the best glider we have ever built/flown. We only used the power on initial climbout, the rest of the flight was thermal/slope off the top of hill at our field here in southeast Ohio. You will probably get another order for a kit from some of the onlookers that watched in ahhhhhh as these birds flew. Thank you for a great plane.
Frank Groza
Larry Townsend


Ron Bloch's elect oly III

.... Ron Bloch joins in the fun with his flying buddies ....

Ray,

Just a little note to say I LOVE THIS THING!! The Oly III is one of the best birds I have flown. I fly with Frank and Larry and after seeing theirs I had to build one with the electric setup. We put a little more down thrust in the motor 8 deg. to see if that would help on clime out, but still took 1/2 down at full throttle. This thing just wants to climb.
Landing with the flaps and spoiler was spot on.
Thanks for making This GREAT KIT!!
Ron

Terry standing with his Oly II S Terry setting up his Oly II S
Terry's Oly II S launching

Terry Traver's Electric OLY II S

Ron Folck and his Electric Oly II

Ron Folck's Electric OLY II

Hi Ray, Just finished my Oly ll electric. I got from you 5 months ago and it has been around 10 below for about three weeks and just wanted to tell you it was an easier kit to build for the first timer than I thought. (you really have to follow directions close and plan ahead) I have flying since the late 60s and just fly sailplanes, I have a brand new pulsar pro 3.2 electric and haven't flown it yet but look forward to flying them both for the first time.

Thanks, Ron Folck

Matthias Alfons Altmeier

Stiffnecker's Delight

Hi Ray,

1. ...this bird looks great from every angle (and what looks good generally flies good as we all know) - and gave me two wonderful years of relaxed and ultimatelly enjoyable flying so far. 30 minutes in no-lift conditions are my standard duration. What I like the most about my Li'l Bird (2m) is the fact that it is a very sensible thermal hunting machine. Your design struck the right balance between sensitivity and stability! It centers well in a thermal, gives clear lift indication, penetrates well on demand and reacts to the smallest control inputs instead of plowing mercilessly through lift and requiring "king-kong-like" rudder or elevator deflection like many other RE(S)-machines.

To see that bird circling overhead and knowing that I put this ingeniously crafted kit together all by myself gives me a unique and very enriching feeling that simply cannot be beaten by an ARF product. Wood is sexy! That´s why I sold my 12foot ARF glass glider after a few flights. I cannot connect with ARF-kits. To me these products are not "bad-" they are simply "no-karma-stuff".

My equipment:
Graupner 480 motor with a 3:1 czech reduction gear and a 12X8 prop, Sanyo 7cell battery 1500mAh, Robbe speed-controller "air-control 819", some chinese no-name (GWS) servos. Flying weight: ???? Still light enough. I knew it once exactly and will send you that information tomorrow.

2. Question: The dollar is a low as never before (no Schadenfreud involved from my side) How much is S&H to Germany for the OLY III or the Sky Bird?

All the best for now.

Matthias Alfons Altmeier (Commander, German Navy)

Matthias's Lil Bird Matthias's Lil Bird Matthias's Lil Bird Matthias's Lil Bird Matthias's Lil Bird Matthias's Lil Bird


Mini Lil'Bird E

Beautifully covered mini lil bird E
Long flying park flyer - naked

Isn't it time for a duration Park Flyer ?
Kit price ... $79.95

Mini Bird E Specifications
Flying Weight
(Less Battery)
7 oz.
Wing Area259 sq. in.
Wing Span50 in.

Mini Bird E Building Instructions

Hacker A10-13L outrunner may be a good motor choice.
20 grams, 3/4" diameter, and 75W.


Lil Bird 2 Electrified

Click here for kit info

Chris's motor installation
Chris's Lil Bird 2 fuse
Chris's motor installation

Ray,

Attached some pics of my Lil Bird 2 showing details of the motor/electrics install.

The motor/esc/battery details are:

  • KDA A20-50S 1080KV Brushless Outrunner (from Hobbyking)
  • ESC 15amp Hobbyking
  • Battery 3cell 500mah Zippy
  • Prop 8x5 Aeronaut

The motor is really light (32gm) and battery needs to be well forward for best flying CG. Obviously keeping the nose as long as possible helps here, I added no ballast. I build in 5-6degrees of down-thust and 2-3 degrees right but thats not critical as a little mixing on the TX gives me a good straight climb-out. Its a reasonably tight fit but with these small electronics I didn't have to widen the fuse, modifications from plan were minimal.

The glider weighs in at 327gm ( 11.5 oz ) including battery. A bit heavier than the intended HLG weight but flies beautifully none the less. The motor draws a mere 7amps at full power and I can get 4-5 to powered climb-outs to 150-200metres which is plenty, obviously with just 500mah in the tank you need to manage power use. Having got rid of a small warp in the wing and adjusted the CG to my liking it will signal small amounts of lift easily and stays aloft very well. Very easy to fly tho smaller gliders can be a little twitchy compared to a 2.5metre ship. I love flying this little glider, definitely a keeper.

Chris


2ME LIL BIRD

Ray launching 2ME Lil Bird
Ray in action with his 2ME Lil Bird


Hi Ray,

In this Age of ARF's, it was well worth it to build the 2 M E Bird. It flys, SOARS fantastic. I installed a Speed Gear 480 Race swinging a 10/8 folder.

Thanks for a great Soaring Bird, all my friends say I have a winner.

Roland Herzig


Do you know how important low wing loading is to electric powered thermal sailplane's flight performance? Have you been turned off by the low performance junk on the market, I guarantee you will be thrilled with my electric 2M Lil Bird. I love flying this bird.

You can fly it in very small areas, due to the low wing loading, landing approaches can be very short and slow. My designs are known for lack of tip stall, so it is very stable on a very slow, nose high, landing. This means added durability and relaxed landings.

As with all of my designs, this is not a high production, cheap, but over priced, fragile (make the CEO money) kit. It is very durable and will last a new pilot a long time. The 1/64" plywood fuse doublers in the kit are far superior in strength than a balsa wood doubler. Photos of parts and construction can be viewed by clicking on ASSEMBLY TIPS, it is a simple model to build.

Parts for the 2ME Lil Bird

Pictured above are the parts that make the 2mE Lil Bird a great electric version. Notice the plywood motor mount has three tabs to correspond with the two slots in the fuse sides and doublers as well as the slot in the fuse plywood bottom. This three point mounting system will ensure a very strong motor mounting that will survive hard landings. The four triangular pieces are used to allow the fuse sides to fair into the prop spinner. The bottom battery hatch includes the stop rails and mounting pieces and hardware. Please notice the plywood doubler has holes receive the wing mounting pegs, but the fuse sides do not. This allows the builder to build the 2M Lil Bird with a bolt on wing rather than a rubber band hold down and not have the holes in the fuse sides to contend with. The bolt on wing is highly recommended for the electric 2ME Lil Bird and only one nylon bolt is necessary.


2M LIL BIRD WING CONSTRUCTION
UP-DATE 7-2013

All the wing Laser Cut plywood spar braces included in the kit can be installed when hard launching, zoom launching or aerobatics are performed.

If you are installing an electric motor, only the plywood spar braces shown on the construction plan need to be used to have an adequately strong wing. Eliminating the other center dihedral plywood spar braces will save weight and building time. The wing will still be very strong regardless if you build a one or two piece wing.

Installing electric motors in Sky Bench Woody kits has become very popular due to the availability of current light weight motors and Li-Po batteries. A good place to start the motor thrust line setting is 2 degrees down and zero off set. The amount of thrust ( watts ) your motor, prop size/pitch and battery produce, plus your flying style preferences will determine the final thrust line settings.

Sky Bench has sold hundreds of 2M Lil Birds, everyone has been delighted with the flight performance.

Woodys Forever


Ray,

I just finished putting E power in my 2m Lil Bird, and flew it today. I put in a 375 watt Tower Rimfire with an 11 X 6 prop. It climbs to 200 meters in 20 seconds, great little flyer. It only weighs 34 ounces with all the gear and a 1300 mah Thunderpower 65C 3 cell Lipo. I had taped up the spoilers, but activated them today again. Next is E power for my flapped Skybird. I read the LOFT site all the time.

Bill


Interior motor area dimensions W 1-1/2"   H 1-15/16" plus canopy cavity.

2ME LIL BIRD KIT PRICE........$149.95

Conrad's 2ME
Conrad Cooke's E powered 2m Lil'Bird

Charly's 2ME open hatch, battery removed
Charly Bobines 2m Lil'Bird E under the hatch.

Charly's 2ME open hatch, battery installed
Charly Bobines 2m Lil'Bird E under the hatch #1.

Charly's 2ME full shot
Charly Bobines 2m Lil'Bird E.


Hi Ray,
Thought you might like to see a picture of my (finally) finished 'Lil Bird 2M E. Had maiden flight this evening, and it was totally successful. All I need to do is maybe put some expo on the very effective elevator, and add a bit more downthrust. Flies very well; just floats beautifully. Lands pretty hot. If I were to do it again, I think I might add small spoilers.

I used an Eflight Park 450 brushless outrunner, an Eflight 30 Amp Pro BL esc, a Graupner CAM folder with 12x6 blades, and a Thunder Power Pro Lite V2 3S Lipo pack. I mounted the motor on a slide-in plywood mount, which makes it much easier to remove to change blades, etc. Couldn't really get a good grip on motor when tightening prop nut while in the plane. And, getting to the lower mounting screws would be very difficult with motor in the plane. Works for me! It fits very snuggly, so no slop.

Thank you for a very nice design and an excellent kit!

Dan Juhlin
Seattle, WA

Full overview of Dan Juhlin's 2ME 'Lil Bird
Interior fittings of Dan Juhlin's 2ME 'Lil Bird

Flight Report

Hi Ray,

Wanted to give you an update regarding my 'Lil Bird 2M E. Took it to a proper thermal field today so I could really try it out. Conditions were very good, just a light breeze at times (probably thermals blowing through). I have built and flown a number of sailplanes, with this being my first electric one, and I have to say, this plane flies as good or better than any I have had! What a joy to fly, so sensitive to the slightest lift, turns tight enough to core the tiniest bubble. When I am flying it I almost forget it has a motor! I flew for 45 minutes on the first flight using a total of just over one minute of motor-run time! Could have stayed up much longer on the pack, but my neck was getting sore. Subsequent flights were similar, even after the thermals had died off and the air got very flat and still.

Won't be doing any DSing with it, but you drop the nose and build up a bit of speed and she'll make a nice quick fly-by! And all the loops, inside and outside, inverted, and even a big kinda sloppy barrel roll.

Thanks again for a fine design!
Dan


Bob in Seattle with is electified Lil Bird 2M

From Bob in Seattle: Ray, I can't tell you how much I love flying this plane. I'm just making sure that I have a spare on the shelf in case of an accident.

Thanks for the order Bob, I love flying my 2M Lil Bird too.


electbb.jpg (46327 bytes)

Electric Big Bird

The Big Bird converted to electric is a very good flyer. With some thermal activity and it will easily fly for an hour or more. The airfoil provides a very flat glide and will thermal out on light lift. The Big Bird kit is fully laser cut, fuse formers and sides have tab/slot engineering for easy assembly. Plans are drawn in CAD and include the electric installation. This is a very high quality kit and includes an Astro Flight 608G motor installation drawing by Jack Hamilton for LMR events.

My Bird Series, Lil Bird 2, 2m Lil Bird and Big Bird all convert to electric power and the flight performance will amaze you. The Bird Series designs use the S 3014 airfoil for excellent float and penetration and does not have tip stall tendencies. We build them without washout and the result is full utilization of the wings potential performance.

SEE "ASSEMBLY TIPS" FOR CONSTRUCTION PHOTOS AND BUILDING TIPS.

Interior motor area dimensions ..
W: 1-1/2" H: 1-1/2" L: 3"

Kit Price........$169.95 Satisfaction guaranteed!


Suggested Electric Motor Installation ......

AXI 2820/10, 13X6.5 folding prop, and a 7 cell 2000 mAh battery or 2 or 3 cell LiPoly battery with a Jeti "Advanced PLUS" 40 amp controller.


Bill Grenoble placed 3rd in the 2012 CAMS-Polecat-Soaring Circuits contest flying his Big Birds. Congratulations Bill, you were the top scoring WOODY.

It is a wonderful feeling to do well in today's contests that are dominated by store bought, $2000.00 PLUS imports, with a WOODY built and flown with your own hands. Woodys Forever.

From Bill Grenoble:

I fly two 100" Skybench Big Birds for ALES, one with flaps, one with spoilers. They are equipped the same. Rimfire 15 motors (Tower), Castle 50 esc, 1350 TP 4 cell 65C batteries, 11 X 8 props They will climb to 200 meters in 22 seconds if I want to, and I get 5 climbs/flights to 200 meters in a contest. I only turn on the flaps/spoilers when coming down to land. Weight-- spoilers: 51 oz, flaps: 54 ounces.     Bill Grenoble


Electric Big Bird XL

The wing is extended two bays in each inner wing panel, resulting in a 110" span. This lowers the wing loading and will be ideal for an electric motor powered glider.
Use the same suggested AXI motor set up as the Big Bird noted above.

Tony's Electric Big Bird XL at the Nats

Ray,

Thanks to Mike Cramer, here is a picture of Bill May and me at the 2009 Nats with an extended wing Big Bird. Bill placed 6 out of 15. The plane performed very well against all the CF wonders. Note the modified fuselage built from a crutch construction. this narrows the cross section and I think signifcantly improved the performance. Much harder to build and the equipment gets shoehorned in but the end resullt was worth the effort.

The nose hatch goes on after we connect the batttery.

Tony Stamp

Interior motor area dimensions ..
W: 1-1/2" H: 1-1/2" L: 3"

Kit Price........$179.95

Electric Motor installation Build thread. RC Groups


Stamp's and May's Electric Big Birds

Ray,
Sending a picture of 2 Big Birds that Bill May and I completed today. Hope to fly one tomorrow, weather permitting. So far I have built 3 little Birds and 3 Big birds one of which is still in a Muncie cornfield. They fly great and the kits are well done..
Tony Stamp
Dunlap, TN


Big Bird Electric, Ken Troxell March 28, 2003

i am running a trinity chamleon 19t pro car motor with a 4.4:1 planetary gear box,14x8.5 prop,jeti 35 amp controller,and a 1700 7-cell pack. climbs to winch height in 30- 35 seconds at 60 degree angle. if i did another i would use a jeti 30/3 brushless, 8 cells ,and a 12x6 prop.
ken


Electrified Big Bird by Bob

Hello Ray,

I spoke to you at the contest at the AMA site about the end of May. You took me to a Big Bird to show me how to make hooks at the wing roots to use rubber bands to secure the wings. I used that idea and attached is my first kit-built sailplane. (not my first kit) :-) . That contest was the first time I had seen a sailplane meet and winches in action.

I finished my Big Bird last week. I put the maiden flight on my Bird Saturday, July 1st. WOW is all I can say! We are not a sailplane club........but I handed the transmitter to a very experienced aerobatic pilot who also was an avid sailplane guy for a while. His judgment is better than mine because he has competed and flown all types. His reaction was the same as mine.....WOW!!

You have one wonderfully l designed sailplane in this XL Big Bird. (As I am sure all the Bird sizes are).

I know your plans showed a geared can motor....... If anyone needs some info for an AXI you can save my email and refer them to me. I have some build photos I can send them, etc. OR ??

With an AXI 2820/10, 13X6.5 folding prop, and a 7 cell 2000 mAh battery, the RTF weight came in at 58 or 59 oz. I figured the wing loading to be about 9.5 oz. sq. ft. I have Li Po's coming and with a 2 cell and same prop, (a little less power), this thing should come out to about 7.8 oz sq. foot wing loading!!! I have PLENTY of power to climb with 59 oz...........so I am thinking the 2 cell LI PO will still do a good job. Moto Calc program says so too.

Again......... thanks for your help and being so cordial at the meet, especially since you were the CD that day.

Yours Truly,
Bob Ruder
Indy.


Electrified Big Bird by Jeff

This aircraft is just a dream to fly. I haven't flown it in too much wind, about 10mph. It is just so graceful in the air.

I have used an Overlander T2836/8 motor, 1120Kv, 290 Watts, 8 winds and a 20Amp Esc with 3 cell lipo at 3000ma.

There is a video on Youtube. Go to jeffperkins100 and have a look at electric big bird.

I have also attached a couple of photos.

The black tape on the rear of the fuselage holds a small metal bracket with a nut and bolt on it so you can add or remove weight to make it tail or nose heavy.

Thanks for such a great kit.

Jeff Perkins


Caffrey and Electric Big Bird XL

Hi Ray;

Its been months since I've talked to you. I hope you are well.

You'll find a photo attached showing 3 old birds and 3 gorgeous Big Bird XLs. The red-winged bird in the middle had just flown its maiden flight out of the SAGE field in Marana AZ.

From left to right; Mike Caffrey, Dirk Christie, and Ed Julia (photo by Neal Obert) (FYI left is flapped, middle is plain wing and right has spoilers.)

I showed up at the field about 2 years ago with a 100" electric Big Bird. Ed Julia was impressed with how it could fly slow, and how well it could penetrate so he built one, then Dirk followed. I think there are a couple more guys who are on the verge of making Big Bird purchases as well.

By mid-March, we'll go from a 'finding lift' problem to a 'can barely see it' problem here in the Southern Arizona desert. You've really got to check out our thermals sometime!

It's about time for me to start on another 2 meter Lil' Bird - I'll drop you an order soon. (My last one got too high and I lost sight of it (mid-June)).

Mike Caffrey

Tucson, AZ 85750

Sky Bird

For kit and specs information please go to the Bird Series page.
Builder Conversion to Electric NOTICE

If you want to install electric into a Sky Bird, the rear wing rod and associated brass tubes can be eliminated during construction and will be a good weight saver. A single wing rod instead of two rods, placed in the front spar will be very adequate...

A Sky Bird kit with only the single wing rod and related brass tubing is priced $10.00 less

Electric Version Kit ... $189.95 ... Shipping $25.95


My new Sky Bird

Hi Ray. Here are some photos of my new Sky Bird, along with its little sister Big Bird XL. Both have electric power. The Big Bird has been flying for a couple of years and loves to drift in the light summer air. Flaps make spot landings much easier, and a tiny bit of camber in the flaps improves thermalling when needed.

I completed the Sky Bird this past winter, also electric powered. The fuselage was shortened 2 1/2 inches at the front end and the Neumotor 1506/1.5Y inrunner with a 5.2:1 gearbox and a 3 cell 2650 mAh lipo coupled to a Castle Creations Phoenix Edge 75 Lite Speed Control serves up 600 plus watts with a 16 X 6 Aeronaut CAM folding prop. Total all up weight is 5.1 pounds resulting in about 120 watts/pound. This promises excellent climbing for LMR type flying, yet the cubic wing loading of 2.9 promises excellent thermalling flight characteristics. It also has flaps. This new Sky Bird should be airborne within days.

Love the SkyBench kits. Best wishes. Bill Jones, Kelowna, BC, Canada

Bill Jones with his Sky Bird and Big Bird XL
Bill Jones' Sky Bird's motor installation

Lil bird 2, Electrified, stretched and flapped

by Bob Egan

Ray,

Here's some pictures of the first attempt of adding flaps. It works, but it's a lot of work and may be more complicated than necessary. Looks like the completed wing with servos and joiner rod would be a little over one ounce heavier than the one I sent to you.

When we were talking about adding flaps you mentioned hinging the flaps on the bottom. That may work better if we don't need to reflex to flaps up and don't mind the look on the on the wing top side.

Bob

Hinged building board
Wings without flaps Wing with flaps deployed
Nose Compartment
Servo Rails
Battery Hatch Battery Compartment
Servo Tray
Logo

Electric Sun Bird



Sun Bird “Electric” By Michael Morgan


First off I would like to thank Ray for his commitment to producing very high quality laser cut kits and Dave Thornburg for his great design. I was in search of a plane to build for a Speed 400, 7 cell, last plane down event. The Sun Bird’s classic elliptical style wing and T-Tail design attracted me to this aircraft. I ordered two kits from Ray and was quite surprised to see them at my doorstep the next day. After an evening of carefully going over the plans and re-designing the nose section to fit a conventional Speed 400 motor and gearbox, the plane was assembled and covered in approx. 30 hours.


The power system for the Sunbird was designed to give a near vertical climb. The original setup was a 6 volt Graupner Speed 400, Maxon 4.4:1 planetary gearbox (see picture below), 10-6 Graupner folding prop and a 7 cell 500 ma battery. Using the Astroflight Watt meter, the current draw showed about 9 amps. On the first flight it was very clear that this was going to be the plane to beat, but the plane needed more prop or RPM to increase the rate of climb.

We switched over to a 5.2 volt Rocket motor and an 11-6 Graupner folding prop and we almost doubled the rate of climb. We finally achieved about a 45-degree climb drawing about 11 amps. This should give the plane about 6 thirty-second climbs of about 200 feet.


The fuselage with a re-designed nose section was the only area that changed from Ray’s original design. The T-Tail was made removable, the wing mounting was changed to an internal style mount, and carbon fiber was added to the inside of the fuse at the tail section for extra strength, Basswood was added in critical areas of the fuse, including a battery hatch on the bottom of the fuselage to increase strength.

A modified fuse former was placed at the wings leading edge to hold the 3/16 dowel that was located in the leading edge of the wing.


A hatch was created on bottom of fuse to access the 7-cell battery.  The hatch and wing are held in place with steel threaded pin that screws into a blind nut located in the trailing edge of the wing. It also serves as a landing skeg/pin for those pinpoint landings.



The T-Tail was made to be detachable by a 2-56 screw and plywood clamp for easy transportation. A hardwood 3/32x1/4” leading and trailing edge was added for strength.

Note. the stab slots and corresponding fin tabs provide alignment and are lazer cut by Sky Bench.


The wing was built to plans only adding 1/16 plywood doublers at the external dihedral joints. The wing was sprayed with a light coat of Kraylon paint and then covered with Mylar film from Model Research Labs

Overall this kit was very easy to assemble and the flying quality is excellent.





Foot note by Ray Hayes

Sky Bench Aerotech is indebted to Mike Morgan for this great report on converting a hand launch Sun Bird kit to electric power. Mike is the first to convert a Sun Bird and joins Bob Steele, the first to convert our Lil Bird 2, which is also a great electric flyer, to Speed 400.

It is obvious, the guys with building skills are getting the most enjoyment from their model aviation hobby.


Another Electric Sun Bird

Electric Sunbird Mod (Click to enlarge)

Ray,

Here is the 'lectric mod of Sunbird.

Simprop 280 BB in a 5 to 1 gearbox swinging 7.5 x 4 Graupner Cam Folder. 3 Lithium Polymer 1020 cells. All up weight - 14.7 oz.

The mods were made centered on getting the Graupner prop spinner to align with the fuselage. This widening was done by splicing a 3/8 by 1/8 ply strip into former 1 and creating a former for engine mounting at the same width as the new F1. A 3/8 inch block of balsa was added to the belly to provide fairing to the spinner. A new servo tray was fitted to the widened fuse. Very little to modify as the fuse aft of F2 is unchanged. 1 degree of downthrust relative to the stab

The worst part is the gearbox I chose takes up almost the same space as the spinner diameter. It is a regular old "offset" box (MJ8005 HobLob) This made for a paper thin fuse right at the spinner. This needed to be fiberglassed for strength. Since I was glassing here, I decided to use 3/4 oz glass on the fuse and fin. To keep the weight low it was attatched by spraying 2 medium coats of laquer on the fuse and fin. The glass cloth was misted with laquer and attatched with laquer thinner. Goes on as easy as wet silkspan! Filled the glass with 2 coats of polycrylic, 1 coat of auto primer and 1 coat of Krylon white.

The motor-box-prop can draw 5 amps which really pushes the health of the LiPo celles, so I climb at 75% throttle. One minute to hi-statr altitude. I get 15 climbs off this set-up.

Let me know when you get someting on the Legionaire Shuttle as I already have some prelim stuff for wing mounted landing gear and power train.

Roy


OLY ll S Electric Power Conversion

Bruce's Electric Oly IIS (Click to enlarge)

Ray
It flies like a dream. NO TRIM CHANGE OR BALANCE CHANGE. I'm just about as happy as an RC flier can be. Amazing sailplane!!

Bruce


Electric Oly IIS Mod - Front (Click to enlarge)
Electric Oly IIS Mod - Back (Click to enlarge)

.. Interior motor area dimensions ..
W: 1-3/8" H: 1-5/8" L: ADJ. 2-1/2" to 3-7/8"

Converting the OLY11-S to electric takes little modification. I chose the E-flite 15 motor paired with the matching 30 to 40 amp controller. This motor is the outrunner style. For weight purposes and long, powerful runs I used a Thunder Tiger 3 cell 1100 li-poly battery. To finish the package a 1 3/4 inch spinner was installed on the shaft with a12x5.5 folding propeller.

The fuse was built stock as per plans with the exception of leaving out the nose block and the tow hook block. Also there were four 1/2 by 1 inch slotted holes cut into this area to provide for cooling. For the motor mount I measured the inside of the fuse and cut a piece of 3/16 aircraft ply [not light ply] to fit. Using the supplied motor mount I traced the vent and bolt holes into it and drilled them out. Using the motor mount and screws supplied with the E-flite motor I then mounted the motor using loctite as you will not be able to get back in there later to retighten them later.

This assembly is then slid into the fuse and epoxied in place. In order to get as much right and down thrust I used scrap 1/16 balsa as shims and let the motor rest on them as the epoxy set. To finish the fuse slices of the nose block were used to fill in on the sides and top and were then sanded to blend in to the spinner. I left the bottom open for ventilation. As this was my first E sailplane I was pleased with the outcome and learned a lot.

As for the radio installation, place the servos, receiver, battery, and switch into fuse and adjust fore and aft until the balance is where you prefer and then rigid mount everything. I used two pieces of 1/4 square hard balsa stock to capture the battery, one at the rear and one loosely set over the top. With the battery leads ran through the former it stays there and hasn't shifted yet.

Flying Report

WOW! This combination is powerful. I can climb out at 60 degrees right out of site several times. This combo has to be at the upper end of the scale. This OLY2S E version has GUTS. Control is quite crisp and the sink rate is only slightly higher than the glider version. Slowing down for landings is done quite well with the application of the spoiler and elevator with no tendencies to snap or fall off. Slow speed control was never compromised and felt solid right to touchdown. I would recommend that the fuse bottom have some sort of added skid added to protect the fuse bottom as well as the spinner and blades.

I highly suggest you build your own version. It has been great at lunch time to get in a couple of flights. My fellow club members have enjoyed it and I expect to see a couple more around soon. Sky Bench planes have always been top notch in quality and value and with this simple conversion now you can have an excellent E powered glider that will not let you down. Bob Legue


A Pair of OLY ll S Electric Power Conversions

Max and John and their Electric Oly IIS's Max handing John his Electric Oly IIS

Hi Ray,
Max Mills has completed my beautiful flying and constructed Oly IIS RES now. It weighs 42 OZ RTF with a 2000 mAH battery pack. Futaba 7 channel FASST 2.4 RX & TX and covered in ultra coat.

Attached are two pictures. One of Max and I with his and my Oly IIS’S and one of him handing over my completed Oly IIS. If these photos are good enough feel free to use them. If not I can shoot more. Max and I thank you for providing such a outstanding kit with great wood.

Thanks again,
Max Mills and John Renker

Foot note by Ray Hayes

John & Max
Thanks for the photos John, as I have said before, since your no longer able to build models, "you must be one of the luckiest modelers in the world to have a supreme builder like Max Mills put your sailplanes together". I'm honored to have you both as customers. Ray


Another OLY ll S Electric Power Conversion

Electric Oly IIS - Again

[Click here for more Oly information]

Hi Ray,

For a few of months I've been self teaching myself to fly RC sailplanes so electric makes more sense for my style. The OlyIIS flies the best of all I have in the hanger. Stays up better and penetrates better too. The kit was top notch and a pleasure to build. I added spoilers in the wings and managed to keep the weight with in 3oz of your pure glider Oly. Very happy with it, fly it two or more times a week most weeks, and wanted to say Thanks. I've attached an image of me and the Oly at Mountain View Park today. Oh ya, when folks walk by and look they go past the foamies and ask about my Oly....it's pretty.

James McDaniel
Phoenix AZ

Cyril and his Electric Oly IIS

Cyril George's OLY ll S

Cape Town South Africa

Bill Halstead's Challenger with lights
Bill Halstead and his Challenger at dusk

Bill Halstead's Challenger set up for Night Flying.

This has to be a lot of fun, thanks for the pics Bill.

Windlord and Ken Bates

Windlord for Electric or Winch

Ken Bates assembling his Windlord at Wood Crafters

Superior Flying Wing performance designed by Ken Bates

Semi Kit includes: Laser cut parts as shown in photos.

Partial kit ... $89.00
5/16" Wing rod - brass tubes ... $18.95

See Ken's build thread on RC Groups

Purchase plan #215 from AMA Plan Service


Here's a few pictures of how my Windlord kit came out. I used a 35-42-1000kv outrunner, 2200mah lipo, 11 x 8 folding prop and put servos in the wing for the elevators and air brake. The front cowling is similar to the Sagitta series gliders (I'm a woody) and the rear access hatch has a ply tongue with a magnet on the back. The hatch handle is part of the dorsal fin. Flew it today for the first time and was totally amazed at how stable it was. The only change I made was to put in more down elevator during the motor run to keep it under control. Thanks for a great kit.

Gene North

Gene's Windlord front view Gene's Windlord back view Gene's Windlord hatch Gene's Windlord inside


Windlord laser cut parts 1 Windlord laser cut parts 2

Windlord Laser Cut Parts

Richard Robbins and his E- Merlyn
Richard Robbins and his newly completed electric powered Merlyn

Inside Richard Robbins' E- Merlyn

This is the Motor equipment Richard is using:
Prop: 18x6
Motor: Power 60
ESC: Hobby King 60 A
Battery: 2280Mah 5 cell
Peak current 67 amps 1178 Watts
Weight: 9# 14oz
2000Mah 4 cell nimh for the receiver and servos.


Richard Robbins maiden flight of his E- Merlyn

April 6th, 2012, Richard maidens his electric powered Merlyn.
Pictured are his beautiful Merlyn and OLY lll, both are E-powered. I drove over to Ohio to record the event on a movie, Don Harris hand launched the first flight and and we all had a hold your breath moment. Almost immediately after Don released the Merlyn, Richard inadvertently opened the spoilers. What a showman ... :-) :-) :-) ! We all had a turn on the sticks, it preformed beautifully.

Bob Barger of Elkhart, IN with his EP Merlyn
Bob Barger has been flying Merlyn's for years. This one is launched by an electric motor.

 


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