Thursday, November 1, 2007

Black Horse Models Super Air Glow to Electric Conversion

When I was a boy my Father would take me to one of many local flying fields. My job would be to clean down the oil covered models after each flight. Or if I was lucky enough I got to hold a model and point it skyward during the all-important run up stage.

While I gravitated to the scale and warbird models, the guys who flew the pattern ships always seemed to have more fun. Unlike the warbirds that would fly the pattern, loop and touch and go the pattern guys were crazy! W.O.T passes inverted at altitudes nearly dragging the rudder were common! These pattern guys always seemed to press their luck and came away smiling even in the event of a disaster.

Flash forwarding 30 years the Black Horse Models Super Air looks a lot like the Birdies, Kaos and Kwiks that ruled the skies all those years ago.

I first saw this model sold under the Graupner name a few years ago. With a price tag of over $150 for an ARF I never seemed to be able to afford it. Till now that is.

The Super Air is now sold under the Black Horse Models name. For a mere $79 and a phone call to Hobby People you can have one delivered to your door ASAP!

My Model arrived double boxed and neatly packaged. The first thing you notice about the model is how light it is! You can read the complete build thread here but I can tell you the airframe alone with it’s ½ lb miscellaneous parts bag weighted in at a mere 3.5lbs!

The second thing you notice is the covering. As the model is made in Vietnam I would describe the covering as Vietnamese wallpaper! Seriously, if you have purchased any ARFs from the 80s you know exactly what I’m talking about. It’s the type of covering no matter how taught it is will wrinkle up like your Grannies left butt cheek after some time in direct sunlight. A heat gun is all it takes to return the tautness but this can get tiring for some.

Covering aside it really is a nice model. All the control surfaces are pre-hinged and those hinges are pinned. The hardware supplied is a grade above what normally comes with typical ARFs out of China.

Power System

I chose the E-Flite Power 46 outrunner for power coupled to a Castle Creations 80A Phoenix speed controller. The motor mounted easily using plastic standoffs found at the local hardware store. The standoffs are using the stock down and right thrust of the firewall.

Directly behind the nose gear a battery hatch was built. In the earliest conception I had thoughts of running a 4 cell Lipo in the 3500 MA range. This hatch would have worked perfect.

On a 4S 3300 Thunder Power Extreme I was able to make 700W on a APC 12x8E Prop. As I was looking for closer to 800W I moved to a 13x8E Prop. Now we were making 764W for a cost of 50A. However even with larger aftermarket wheels flying this model on a 13” prop would leave little margin for prop strikes on the ground.

As the model got closer to completion it also became obvious the small 3300 4S pack would not be heavy enough to balance the model. Even replacing the 2 elevator pushrods and rudder pushrod with 2mm carbon fiber rod was not enough.

Replacing the 4S 3300 with a Max Amps 5S 4000 gave me the added weight and power I was looking for. I mean rather then add a bunch of lead to the nose we basically just added a cell.

On 5S we were now making 1200W for a cost of 64A on the smaller 12x8E prop! That’s at or about 200W per pound! Oh yes, that’s a LOT more like it.

The all up weight of the model is 6 lbs ready to fly.

Maiden Flight Report

There is something majestic when a trike leaves the ground in a shallow climb. Even ugly planes somehow look graceful. Well forget graceful, the Super Air with 1200W will jump into the air nothing flat behind that 12” prop if you prefer that style of flying. I think the pattern guys of the 70s and 80s would have loved to see that!

Having read a lot of magazine articles I’m always amazed when I read about another pilots report of ZERO trim required. I mean come on, zero trim? Anyways apparently I have joined the Zero trim club. I did not touch the trim levers at all during the 5-minute maiden flight. How’s that for an ARF building straight and true right out of the box!

The model has a nice top speed straight and level with very little ballooning when moving from part to full throttle. My setup was right out of the manual. While the model tracked fine, and passed a dive test I think it flies slightly nose heavy at the advertised CG. The roll rate was ok as was elevator and rudder authority. Inverted flight needed a fair amount of elevator to keep the nose up. Rate of climb was especially nice with BIG loops. I set up and landed hot as I really did not know what to expect. My overall impression is this model gives away NOTHING to a glow at 1200 watts.

Tommy D

Saturday, October 27, 2007

Axi 2820/12 maiden report in the Altec Skydancer

What a nice Sunday. It was unseasonably warm with winds in the 5-10MPH range, perfect to remaiden the model at the SEFLI Wingnuts field in Calverton NY. Recently the field “bugged-out” and resituated it’s runway. With winds out of the West it was perfect for flying.

In a nutshell the repowered model fly’s great. Moving to the outrunner did not sacrifice as much airspeed as one might think. As one expected rate of climb has increased dramatically. Take off and landings are a non-issue despite the larger prop. Some of this I attribute to the fact this model floats in for a landing. Flight times are also longer as I no longer find myself flying the model with the throttle at or near the firewall. I did not time them but I would say I’m in the 7-minute range right now. That’s not bad considering I was hitting the ESC’s cutoff at about 4 minutes before!

One area that needs to be improved is the thrust line. I have added 2 shims in an effort to add some down thrust. Also I have shimmed slightly the models leading edge of the wing down to help it stop ballooning.

With just enough time for one last flight I announced that “just one more flight” was in order. Anyone who knows that slogan knows it’s the biggest jinx in the RC world! Having flown the Skydance 3 times before what could possibly go wrong?

As a lesson learned not to challenge the RC Gods about 2 seconds after liftoff the Axi motor and firewall departed the model! The motor had given no indication of trouble up to that point and it was quiet as a mouse. So at about an altitude of 10 feet and little airspeed I had but one choice. There was no going around for sure. I pushed the elevator all the way down to try and get the model some speed and landed HARD at the end of the grass runway!

Being the balsa outhouse that is this ARF she survived without a scratch, and without a motor for that matter.

The motor and firewall has been re-installed and pinned this time for safe keeping. Live and learn for sure.

Wish me luck on upcoming flights!

Tommy D

Saturday, October 13, 2007

Repowering the Altec Sky Dancer .25

Some time ago I built the Altec/Super Flying Models .25 Sky Dancer. Using what I had on hand I flew the model with a Mega 22/20/4 .

The model flew well and has become a plane to take to the field to just clunk around with. In it’s latest incarnation though it was starting to loose some of its attraction though.

To Recap the Sky Dancer was made by Altec/Super Flying models a good 10 years ago and sold by MRC in New Jersey. It was intended to be powered by a .25 glow motor.

It has a wing span of 50 inches and a all up advertised weight of 3.6 lbs. Even converting mine to electric, adding 1 aileron servo per side and larger ailerons I came in at 3lbs 6 ounces!

Upgrading to an Axi 2820/12 and running it on 4S has allowed me to go from an 8x6E from to a 10x7E prop. 525W for a cost of 38A will give me 145W per pound. More importantly moving up to a 10” prop should fly the model a lot better then the tiny 8 inch. With the 8” you felt much like flying a glow model you were mostly at full throttle. Now I would well imagine the rate of climb should be excellent with little sacrafice of top end speed.

To use the Axi outrunner instead of the Mega inrunner I removed the glow rails I had used on the Mega. A simple 1/4” plywood firewall with some triangle stock was glued in for support. Air holes were then drilled to help the Axi breath. I doubt surrounded by all that air it will have a problem with overheating though.

The photos also show the intake scoop for the ESC and battery pack. The scoop doubles as a hatch so I don’t have to remove the wing to access the battery pack.
Ill report back as soon as I fly the model but I expect only good things from the Mega vs the Axi.

The original build thread for the Sky dancer is here

Monday, October 8, 2007

Sunday, October 7, 2007

Multiplex Gemini Sport Bi-Plane Review

Multiplex Gemini Sport Bi-Plane

I recently assembled the New Multiplex Gemini Sport Bi-Plane. Having been a Bi-Plane fan from way back when, selecting this model is a natural for me. There are many small park flying bipes on the market. From what I have found they fly fairly decent at best. Most suffer from their light weight and will weathervane into the wind something awful. The Gemini breaks out of those inadequacy’s as far as I’m concerned.

The Gemini Specs are as follows:

AUW including a Thunder Power 3 cell 2100 battery 32 ounces

36” Wingspan and 36” in Length.

The Gemini is the latest in Multiplex’s line of kits for 2007. The Elaptor foam parts fit very well, but I did take the time to sand the entire model with 400 grit wet paper. It removed the mould marks that otherwise take away Multiplex’s smooth surface. A nice touch is Multiplex’s simulated ribbing on the wings.

Like all Elaptor kits the use of Medium CA is used with a shot of kicker here and there. This was the first kit I used Mercury Adhesives brand of CA and found it to be good stuff. No more clogged CA tips for me! Keep in mind when you use CA setup time to join parts is limited. Use your head to know its best to add CA to the female part and fit the male part into it, not the other way around!

The only change I made was to use the Himax 3516-1130 motor. You do have to drill the mount to use this motor but with the aid of a drill press its very easy. Fitting an APC 10x5E prop and some old thunder power 3 cell 2100s gave me 240W for about 24A draw. I can live with the 120W per lb for now. With new packs next year I hope to prop the model closer to 150W per lb. As is even with these 3 year old packs I’m getting 10 minutes of spirited flight as I rarely fly the model at WOT.

Flying the model I have found pushing the pack to the rear of the bay gives me a nice C of G. Actually I’m flying just rearward of Multiplex’s recommended setting.

So far I really like this model a lot. It tolerates 10 MPH winds very well as that’s about the AVG wind speed I have been flying it in. It truly is a better aerobatic model then I am pilot. Hopefully this model will teach me a thing or two on the warmer days this fall and winter.

While I have talked a bit about how good of an aerobatic model this plane is I cant say enough about how easy it is to fly. Slow or fast, low or high, inverted or straight and level you just feel confident flying this model. If you have flown an aileron trainer this would be a great step up for you. Make sure you set your throws per Multiplex’s recommendations and you will be fine on low rates .

To follow the on-line discussion of the Multiplex Gemini please click here.

Thanks for reading and feel free to leave comments! Tommy D

What matters most, Family

Much of this RC addiction I attribute to my girl Adriana. A gift of an RC airplane one valentines day re-kindled my love for flying. Adriana had seen some photos of me as a kid flying and thought they were cute. I have to wonder how cute it is when your man is running out the door every chance he can get to go flying!

I’m likely one of the few men in this world who after all this time is still at bliss with his girl. Men will rarely admit it however we love to gripe about our women! That’s said, I can’t think of one thing I would change with Adriana if I had the power. Well that’s not completely true, I wish if I had the power I could have one of her children’s books published. That would mean a lot to her.

A little about me.

My First attempt at creating a webpage / blog is here. I did that a lot of years ago and honestly don’t update that page at all now. It does have some old photos on it of people who are close to me or model airplanes I don’t even own anymore. That page will tell you a little about me and my life.


Tommy D's Blog

Created 10-7-07

Life aside this Blog will be ramblings of posts dedicated to RC Model Aircraft.

I would hope this site will help me remember the changes made to a model in it's lifetime.

For giggles Ill toss in some stories from life to keep it from getting too boring!