Electric

NEAT Fair 2009 Report

Daniel Switkin — Tue, 22 Sep 2009 20:41:21 -0500

The 10th annual NEAT Fair took place September 18th-20th, 2009 in the Catskill Mountains of New York. More than 300 registered pilots attended this all-electric show from all over.

Updated 9/27/09: Al Ramsdell from Maine Aerial Photography Service was kind enough to let me post these three shots of the Peaceful Valley Campgrounds. The last two are taken from his Swift 16 aerial photography rig, which he had way up there. Nice flying and shooting Al!

The fog burns off on Sunday morning.

An overview of the show.

From left to right: vendor row, pilots' canopies, and the flight line.

As always, the show is run by the Silent Electric Flyers of Long Island, who come up a week in advance to set up. Many thanks for their hard work, and especially to Tom Hunt for putting on the show.

Nice quad sea plane.

An unusual high wing model with working doors.

An assortment of planes including two Ellipsticks.

A dual-body Radian FPV machine.

A close-up of the camera and video transmitter.

Two beautiful Gee Bees.

Towing the NEAT Fair banner.

Not all landings are perfect.

An assortment of smaller models.

Although NEAT is primarily a fixed-wing show, there was a smaller helicopter presence who enjoyed the 2.4 GHz-only heli stations. Most pilots were 3D flyers, but we had a couple of scale models, and even one fixed-pitch Corona. At one point I watched Kyle Stacy do a warm-up flight with his Furion, which was so fast I couldn't photograph it. His reaction time is just amazing.

A scale Eurocopter with T-Rex 600E mechanics.

Another shot in the air.

Several full-scale planes came and went during the weekend.

My friend Gary from Bulgaria with his Logo 400.

Which he knows how to toss around.

Unusual heli angle.

Me and the Swift 16.

A test flight with the stock 520 mm woodies.

Much better with the 550 mm fiberglass blades.

The noon demos pack a lot into an hour and a half, showing off many styles of flying and a wide range of models. Unlike other shows, most pilots do not fly to music at NEAT, which allows the crowd to hear the planes in action.

Dan Landis and his Extreme Flight Yak.

Sitting pretty in a hover.

Showing off for the crowd.

A nice pattern plane from the noon demos.

An ME-163 Komet with fall-away landing gear.

The Komet in the air.

Are you man enough to fly a pink airplane?

Part of the crowd at the noon demos.

One of a pair of night fighters.

Gary Graf had an impressive first-person-video rig of his own design. He used a 72 MHz transmitter with a 900 MHz video downlink. His on-screen display provided heading, altitude, pack voltage, and more. I ran his video recorder as his flying buddy helped with navigation and held a second transmitter connected by a buddy box cord, as required by the AMA. Gary won best technical achievement at the show for his efforts.

Gary's home-made FPV setup.

Launching the FPV Maxi Swift.

Who ya gonna call? Ghostbusters!

Updated: Check out a video from Gary's Maxi Swift:

The NEAT Fair is also a great place to see some upcoming products up close, and in the air. There were more than 30 vendors present at the show, and many pilots had items to sell in their tents as well. There's nothing like getting face-to-face time with the designer of your plane, and NEAT brings out a number of smaller kit and ARF manufacturers.

The Hobby Lobby 12 foot Telemaster ARF (yes, it's an ARF).

Kids running out for the candy drop.

The Xero Gear booth (it was packed at night).

Shawn and the surprisingly fast Merlin.

The new folding Xeno wing.

The Funcopter, which didn't get to fly this time.

A new LiPo charger from Dualsky.

The Hobby Lobby F-35 jet.

The new Hobby Lobby A-10 with oversized fans.

Wow.

Even more wow.

The upcoming high voltage versions of the Castle Creations ICE ESCs.

A great collection of auto-gyros.

What a streamlined pusher jet.

A Gee Bee and a Carden Yak.

The NEAT Fair is a Northeast U.S. tradition, and I'm glad to see it still going strong in its tenth year.

For even more coverage of the event, check out Paul's photos for RCGroups, and the rest of the NEAT Fair 2009 forum.
read more »

Precision Aerobatics Katana MD Build Notes

Daniel Switkin — Sat, 11 Jul 2009 10:19:36 -0500

The Katana MD is especially good looking in red.

Continuing in our Builds Notes series, this is my experience assembling the Precision Aerobatics Katana MD. This 46" wingspan acrobat is a premium-quality ARF, with a substantial amount of work done at the factory, and a unique carbon fiber reinforced balsa and plywood design.

Rather than writing full reviews, these Build Notes articles focus on the build steps, kit quality, and workarounds for common problems you might encounter.

Pluses:

The ailerons are the best of any ARF I've built. They are not only hinged at the factory, but rotate in a pocket such that there's no gap.
The canopy is magnetic and factory-assembled, no work to be done at all.
The build quality is very good. Both the internal structure and the covering were well done.
The instructions provide a good amount of detail, but the photos are too small, and black and white.
The motor box is pre-drilled for the Thrust 30 motor, which just barely squeezes in from the bottom, but otherwise installs easily.

The cowl is very attractive, but it's a shame it's not magnetic.

This is how the ailerons come from the factory - very nice.

The magnetic, one-piece canopy. Looks great and makes changing batteries easier.

Minuses:

The wheels didn't fit on the axles. I had to ream them out to double the size of the opening.
The main landing gear hardware was different than in the manual, and it used large washers which hit the curve in the gear and didn't sit flat.
The pull-pull hardware did not have enough threads on it, so that it would not clamp down on the carbon fiber servo horn. I had to add some washers.
The aileron and elevator linkages are just too much work and not adjustable when finished. They require wrapping a z-bend with thread and using CA to glue it to a carbon rod, and then using heat shrink tubing to strengthen it.
Fitting the cowl was a hassle and the screws don't look very good. At this price I'd like to see a magnetic cowl, completed at the factory, that just snaps on like the canopy with zero work.
I installed both nylon wing bolts as described in the manual, seating the heads completely flat, but when attaching the wings, both bolts were off by 1/8 inch. I had to bend them significantly to slide the wings on.
The factory made light cuts for the control surface hinges, but they were up to 1/2" off between the control surface and the matching stabilizer. They should be cut correctly or not at all.
The rudder and elevator are supposed to be sealed with clear heat shrink, which is not only tedious, but many ARF builders don't own an iron.
The battery tray may not be tall enough for a 3S LiPo which has spacers between the cells. Plan on using thinner packs.
The carbon fiber stickers on the fuse were peeling up in a number of places.

Notice the washers added on the pull-pull arm.

The black stickers were peeling up in a few places.

Thicker 3S LiPo packs are hard to install and may not fit at all.

Tips:

Replace the aileron and elevator linkages with threaded rod and clevises. These weigh only 2.6 grams each, compared to about 1 gram for the stock hardware, but are much easier to set up.
Insert a wing half on the carbon spar before gluing the nylon wing bolt. Bring the wing close to the fuselage, so that the wing bolt can be aligned with its hole, before applying CA.
Use self-adhesive clear covering to seal the rudder and elevator hinge gaps.
Be careful when using a 2.4 GHz receiver in the Katana, due to possible carbon fiber interference. Make sure to use a full range receiver with at least two antennas, pointed at 90 degrees to each other.
The instructions suggest CA for attaching the stabilizers. I recommend using epoxy for a stronger bond.
Make sure that the lowest rudder hinge will not interfere with the pull-pull control horn.
Check that the servo extension to the elevator servo does not interfere with the pull-pull cables for the rudder.

A shot of the elevator servo wire and the pull-pull cables.

Notice how the washer hits the curve in the landing gear.

Provided linkages at top, replacements on bottom.

Then go have fun! You can also check out Katana MD videos on YouTube or the main Katana MD thread on RCGroups.

Flying An RC Helicopter With An iPhone

Daniel Switkin — Sun, 03 May 2009 10:22:39 -0500

Of all the unusual ways to control an RC helicopter, this has got to take the cake. A guy named Josh has figured out how to use his iPhone as an RC transmitter and has successfully hovered his T-Rex 450 using it. Check out the video here, and his site for the details:

As a fellow software engineer, I have to say that using SSH over WiFi to pull this off is really cool. Now he just needs to find a smaller router. Very clever and original!

Century Swift 16 Improvements

Daniel Switkin — Sat, 28 Feb 2009 20:19:29 -0600

The Swift 16 tail boom compared to a T-Rex 450. Did I mention the Swift is big?

The Century Swift 16 is arguably the best value in large electric RC helicopters. Capable of spinning 500-550mm main blades, it's considerably larger and more visible than a T-Rex 500, which takes 425mm blades. Yet the Swift requires only 4S-6S LiPos, making it much cheaper to power than 600mm-sized electrics. To top it off, the kit has a street price of only $189 USD.

All of that value does come with a cost though. There are a number of minor design issues which you may need to work around. The purpose of this article is to describe those steps as they apply to the current Swift 16, and hope that some of this feedback makes it into the upcoming Swift NX.

Let's start with the head. For the most part it builds easily, and is of good quality. Previous generations had a problem where the feathering shaft introduced vibrations, and needed to be sanded down, but this has been addressed in recent kits.

The washout pins (at bottom left) need to be shortened.

The main problem which remains is the length of the washout pins. Even when fully inserted into the head block, they are simply too long. You'll quickly find that trying to set up +/- 10 degrees of pitch will cause the washout pins to touch the swashplate when cyclic is also applied. The simple solution is to grind these pins down. I took off about 2mm from each pin using a grinding bit on a rotary tool. There is room to take off a little more if you're looking for maximum collective pitch, but make sure the pins come down at least half way into the washout base at full negative pitch.

The kit paddles are very lightweight and should probably be solid and heavier.

The included paddles are very lightweight, and many pilots choose to replace them. The Thunder Tiger "Greenies" paddles are a popular choice. Others have had good luck with solid paddles from Mikado and Century. The stock flybar is 3mm, so buy paddles appropriately.

The bottoms of the blade grips are smooth, with no recesses for the locknuts.

One improvement I'd like to see in future kits is a change to the main blade grips. Currently, you need a wrench to hold the locknut at bottom while using a hex driver from the top. I find this makes it more tedious to install blades than necessary. An easy solution, and one used on other Century helicopters, is to have a recess in the bottom of the blade grip which holds the locknut and prevents it from turning. That way you only need the hex driver, and your other hand can prevent the blade from twisting in the grip as you tighten down.

Now let's move on to the motor mount. The current design has two holes to mount the motor, positioned front and back. This allows motors with different hole spacing to be fitted, and lets the motor move front and back to set the gear lash. The problem is that the rear hole is covered by the main gear. To install this screw, you must turn the main gear until the holes line up. That's mildly inconvenient, but the real problem is that the screw head may not clear the gear. In my case, the main gear was unable to turn with this screw installed. Ultimately I had to grind down the cap head screw and sand the washer to get the necessary clearance.

The rear motor mounting bolt interfered with the main gear.

It was necessary to grind the bolt down.

Installing the bolt through the main gear.

A much better solution would be for Century to redesign the motor mount with the holes to the left and right of the motor. Done like this, both holes would be in front of the main gear, making installation easier and interference impossible. Most compatible motors, like the Scorpion I used, have mounting holes that would fit this design, and any motors with wider mount spacing could be turned slightly.

The white tail pulley has a slight side-to-side wiggle.

One minor issue with the tail is that the tail gear pulley moves a bit from side to side within the gear box. So far it hasn't caused a problem, but it could be improved with a thin washer. Speaking of small parts, the Swift does not come with any spares. A few extra ball links, screws, etc. would cost almost nothing but make sure that customers don't get stuck because one tiny part got lost or damaged.

The canopy can be cut out to accommodate the battery.

Let's spend a moment talking about the battery. The Swift 16 suspends the battery under the frame, which puts the CG a bit lower than is desirable. It also makes changing batteries difficult. I have to lay the Swift 16 on its side, or turn it upside down to change the main pack. Additionally, the canopy is very difficult to install. Specifically, the rear attachment points are a beast to attach - I can easily spend five minutes fighting with them. A good tip is to cut the bottom of the canopy out so that it can be left on when changing batteries.

The Swift NX moves the battery under the canopy, placing it on an inclined tray. As long as the new canopy is easier to get on and off this should be a big improvement. Also, the current landing gear struts are too thin and flexible, which causes the entire heli to shake at a certain rpm during spool up and spool down. The new, thicker struts on the NX will hopefully fix this. In the mean time, many people substitute Align 600 landing gear.

The Swift 16 has an optional gyro plate which mounts on top of the boom, but no good place for the receiver. Some people mount the ESC on the side of the frames to make room for the receiver on the front tray. I mounted my receiver underneath the tail boom mount with double sided tape and a zip tie. It works but is not ideal. By comparison, the Swift NX frames have built-in mounting plates for the gyro and receiver, both behind the main shaft. This is a great change.

The optional gyro plate. This should be included standard.

The gyro plate installed.

I mounted the receiver inverted.

So, what else would I put on my wish list? I'd like to see better quality control, and a better manual. My kit was missing two ball links, had a damaged feathering spindle, and one of the pushrods was threaded wrong. It also came with black rubber bands meant for the old battery mounting tray, which can't be used with the new one. The current manual is OK but has a few steps out of order, and mislabels a couple parts. It also shows parts which have been upgraded or changed since the original design. It would help to correct these, and would be even better to change to a step-by-step instruction format.

Another look at the receiver and gyro mounting.

My kit was missing two ball links.

The finished Swift 16, ready to fly.

While this might seem like a long list, every model has its drawbacks, and none of these should discourage you from buying a Swift. I'm very happy with mine, and looking forward to seeing the product evolve with the Swift NX. With some relatively simple changes, Century could have the best beginner through intermediate large electric heli on the market. read more »

Multiplex Funcopter Announced

Daniel Switkin — Mon, 16 Feb 2009 15:52:05 -0600

Multiplex has released a PDF file of their 2009 product lineup. Perhaps the most interesting new model is the Funcopter, a durable, fixed-pitch helicopter with an EPP foam body. This new heli appears to be based on the Lite Machines Corona, which was famous for its resilient design, including hinged main blades that bend instead of break in a crash.

The Funcopter goes beyond the Corona by being designed for a direct-drive, brushless Himax motor. It also features a scale fuselage (approximately 34 inches long) which will appear larger in the sky, helping with orientation. The Funcopter is designed for 3S LiPo batteries in the 2100-3000 mAh range. It has a rotor diameter of 770 mm and an all-up-weight of approximately 1250 grams (44 ounces).

Two configurations with be available: the Assembled Kit (AK), with just the helicopter and motor, and the Ready for Radio (RR), with all of the on-board electronics. No pricing or availability has been announced yet, but a short movie has been posted.

Our take: This is a very interesting new product, and could easily become the standard beginner fixed pitch helicopter. It's both larger, heavier, and more visible than the current champ, the Esky Honey Bee Fixed Pitch, but being in a larger class, will obviously cost more. Besides being easier to see in the air, which means less chance of losing orientation, the Funcopter should also be more stable. I learned on the Honey Bee, and while it's quite durable, it's also the twitchiest heli I've flown.

Overall the Funcopter design looks quite good. This is the first single rotor helicopter I recall seeing without a main gear, so I'm curious to know how well the power system performs. In theory it means one less part to break and replace. I'm also curious whether the tail is powered from the main motor or has its own motor. The frame looks simple and should provide some protection for the battery in a crash.

My experience with Multiplex products is that they are extremely well engineered. Just the packaging on my AcroMaster had more thought put into it than models from other companies. This tends to come at a premium price, but in my opinion is worth it. We'll try to get a review sample of the Funcopter in the coming months to help you learn more about this unique helicopter.

Update (April, 2009): Check out our hands-on coverage of the Funcopter from the 2009 Toledo Show (scroll down to the Multiplex section).

Arizona Electric Festival 2009 Roundup

Daniel Switkin — Sun, 15 Feb 2009 09:14:45 -0600

The Arizona Electric Festival is held every January in Mesa, Arizona. While it's too cold to fly in many parts of the country, this show brings electric pilots out in force. We're not able to attend this year, but wanted to share some links featuring the best coverage from around the web.

Micheal Heer from RCGroups has put together some great video coverage of the 2009 event, with dozens of in-flight clips. The T-Rex 700 canopy strike is particularly impressive.

Jacob Niehus has also posted an HD video with an overview of the flight demos he saw, and there are a few good clips on YouTube. Also, check out photos from the Multiplex team, including some action shots of the new ParkMaster 3D.

To learn more about this year's show and chat about it, have a look at the RCGroups Mesa 2009 Forum.

Century Swift NX Preview

Daniel Switkin — Mon, 19 Jan 2009 15:14:52 -0600

I was recently in the San Francisco Bay Area for business and had a chance to stop by the Century Heli headquarters in San Jose, California. This building contains the warehouse as well as product development and support staff, in addition to a small showroom in the front. The employees had just returned from the AMA Expo, where they had debuted a number of new products.

The Century Heli building in San Jose.

One side of the showroom with spare parts.

A few scale helis on display on the other side of the showroom.

The Swift NX prototype.

Another angle of the Swift NX frames.

It turns out my timing was perfect as I got a chance to see the prototype of the Swift 16 replacement, which will be called the Swift NX. There are numerous changes to the kit:

The NX uses a double-stacked main gear, which means the tail is now driven during autorotations.
The battery pack now sits on an angled tray underneath the canopy, rather than being hung from below. The prototype still had the aluminum battery tray below but it may be removed before going into production.
The canopy has a completely new styling and is only attached at two points, rather than four. It is somewhat larger and more angular, and the trademark "crater" in the windshield is gone.
The elevator servo arrangement has changed completely. The servo is now mounted in between the frames, and connects to an internal bellcrank which moves a 90 degree elbow to the swashplate. A separate anti-rotation bracket is no longer needed.
Above and behind the new elevator mounting points are built-in plates for mounting the gyro and receiver. Previously, an optional gyro plate was available for screwing into the top of the tail boom mount, and receiver placement was an afterthought.
The landing gear struts are thicker and more sturdy than the previous ones.

The old yellow canopy from the Swift 16 next to the new white canopy from the Swift NX.

Our take: These are all welcome improvements to the Swift 16, especially the battery placement and built-in gyro and receiver mounting points. Hopefully the new canopy will be easier to install and remove than the current one, otherwise changing batteries will be tedious.

I'm a bit ambivalent about the new elevator setup, as I have not had a problem with the older, simpler design. That's not to say there's anything wrong with it - this design is shared by some of the Century nitro helicopters. However it does contain more moving parts and more opportunities for friction.

Other than the items described above, the NX appears very similar to the 16. I did not notice any changes to the head other than the new bearings for the main gear. The prototype had heavier, solid paddles on it which would be a welcome change, but they may have been temporary. This particular heli also had a longer tail boom and upgraded tail boom supports, but I was told they were not going to be used.

No word yet on release date or pricing, or whether some of the problems with the Swift 16 kit have been addressed. Look for an article in the next month describing those issues and how they could be resolved. The Swift 16 remains one of the best values in a 500-550mm electric helicopter, and although I bought the existing model recently, I'm excited to see a new revision on the horizon.

Updated February 28th, 2009: Our new Swift 16 Improvements article is now posted.
read more »

MS Composit Pitts S2 Bulldog Review

Daniel Switkin — Thu, 01 Jan 2009 14:02:33 -0600

Specifications

Wingspan	33.5 in.
Wing Area	Approx. 508 sq. inches
Weight	18 oz. AUW
Wing Loading	5.1 oz./sq. foot
Length	33.5 in.
Electric Motor Requirements	200 Watt brushless motor, 18A ESC, 3S LiPo 1000-1500 mAh
Radio Required	Four channels, 3-4 micro servos
Street Price	$80 USD

The MS Composit Pitts S2 Bulldog is a park flier-sized foam biplane with a true airfoil. The majority of the plane is made of heavy-duty EPP foam, with the exception of the tail group (stabilizers, elevator, and rudder), which is Depron. The kit comes prepainted with a yellow and black scheme and the basic hardware needed, and comes in a simple bag.

The entire kit comes in a bag.

All of the kit parts before starting construction.

Right away, you'll notice that this model has a lot of potential, and also a number of shortcomings. I'll skip to the end of the review a bit by saying that if you make a number of replacements and modifications, this can be a great flying plane. However, the kit as sold off the shelf is only mediocre.

The upgraded wheels on the left, the stock plastic ones on the right.

Let's get a few negative things out of the way up front. The manual is quite poor compared to other manufacturers. This eight page leaflet is vague and meant for experienced builders, and will leave beginners used to a step-by-step manual out of luck. Fortunately, there's not as much work to do as with a balsa ARF.

The included wheels are just lightweight plastic discs, and are fragile to boot. Plan on replacing them with some real rubber wheels, or moving the aileron servo(s) to the top of the bottom wing, and flying without gear. If you do attach the landing gear, you'll want to bend it forward, as the stock position will cause the plane to nose over on almost every landing.

Building

I began building with the wings. The bottom wing comes as one piece, while the top comes in two halves which need to be glued. Although the manual suggests CA with kicker, I used UHU for all similar steps with great results.

Cutting the ailerons out of the wing cores.

Hinging the ailerons with Transpore tape.

Transpore and Blenderm tapes compared.

The Bulldog has four working ailerons, which makes it great for rolls. MS Composit cuts their wings such that the ailerons are built it - the foam itself is the hinge. I didn't care for this arrangement, as it makes the surfaces stiffer than necessary, and more likely to warp when moved. I decided to cut the ailerons free like most other foamies. I applied a small amount of UHU to the foam before using Transpore tape for the hinge. If you have Blenderm on hand, it will work at least as well if not better.

EPP wings have a natural tendency to flex, and like many foamies, these need to be stiffened. MS Composit has a very clever and inexpensive way of doing this. First you cut a slot 2-3 mm deep from wingtip to wingtip. Then you insert a length of string (included in the kit) into the slot, and soak it in thin CA. The string gets hard almost instantly and is quite effective in preventing flex. Many people choose to substitute carbon fiber instead, but it's not necessary.

Using string and CA to stiffen the wings.

The string is used on top and bottom, then trimmed.

The Depron tail is somewhat disappointing, being more fragile than the rest of the plane. I would have preferred EPP, or EPP covered with a plastic film, the way the ElectriFly Yak 55 does. As it is, the rudder and elevator both need to be cut out from their stabilizers and bevelled at 45 degrees before being hinged. I found the best way to do this was to make a 90 degree cut to separate the pieces, then hold the piece on an angle and sand it down to create the bevel.

The beveled edges on the rudder and vertical stabilizer.

I would not have cut the elevator backwards if the graphics had been face up.

Plenty of throw on the rudder.

At this point I have to confess to a building mistake which is entirely my fault. I happened to cut the elevator out with the graphics facing down. By not paying attention, I cut it the wrong way. That is, I made the stabilizer oversized and the control surface undersized. While it functions fine, a serious 3D pilot would no doubt find this setup lacking. The lesson is, pay attention: the edge with the notch is part of the elevator, and faces the rear of the plane.

The elevator slides into a slot in the fuselage and secures easily. However the vertical stab and rudder attach poorly. The stabilizer simply abuts the top of the fuselage and is glued there, which has no strength. A better design would have been one or two tabs on the stabilizer which would lock into holes in the top of the fuse. The rudder has a single hinge into the fuselage which is fine.

I used this stronger hinge to connect the rudder.

The assembled tail with the too-small elevator.

Things are starting to shape up.

Installing the servos takes some improvisation. If you're used to scratch building foamies, this will be second nature, but for everyone else it might be disconcerting. To start with, the manual uses one aileron servo for all four surfaces. I don't like the geometry of these setups, and wanted more torque, so I decided to use two Futaba S3110s for the ailerons with a Y cable.

This step is easier to do before attaching the bottom wing to the fuselage. The holes for the servos need to be cut out, with special care not to cut too deeply. You could also mount the servos on their sides if desired. I spaced them out as much as possible without adding extensions so that the force of the linkage would be closer to the center of the control surface. If you place the servos (and hence the control horn) too far inboard, the ailerons will bend excessively. Even with my setup I found the ailerons warp rather than staying flat while deflected. One solution is to add carbon fiber strips to the trailing edges.

I anchored the bottom wing with two carbon rods.

The Y cable to the aileron servos, with nice straight linkages.

The placement of the elevator and rudder servos is also up to you. I used the approximate locations suggested by the manual, choosing the height of each to get a straight shot to the control horn. One thing I didn't care for is the way the pushrods and their plastic tubes are supposed to be sunk into the fuselage. This bends them a fair amount and adds some friction. In the end I went with it, but standoffs would have worked better. On the upside, the pushrods come with z-bends already made, and adjustable pushrod keepers which make setting the linkages easy. I glued all four servos in place with a hot glue gun to make them easy to remove if needed.

Cutting a hole for one of the tail servos.

The servo lead from the other tail servo needs to come through the fuselage to reach the receiver.

The pushrods can be cut down once installed.

The tail control surfaces hook up in the standard way.

Attaching the wings is not hard but it is important to pay attention to the alignment. Again I used UHU plus a lot of weight to keep everything flat. The struts between the wings interfered a bit with the top ailerons but were easy to trim back. The linkages between the top and bottom ailerons are thin metal and tend to bend a bit. You may want to replace them with carbon rod.

Using lots of weight to glue the wings.

The stock connector between the top and bottom ailerons.

Installing the power system.

Close up of the power system.

All the electronics mounted on one side.

Just one servo and the battery on the other.

For power I used the BP Hobbies 2217-9 brushless motor and the ElectriFly SS-25 ESC, which I happened to have on hand. The plastic motor mount does not secure well to the foam - you may need to experiment to make sure it is retained well. This motor is a bit on the heavy side at 2.6 ounces. I put the ESC and receiver on the opposite side to offset the battery, although lateral CG still proved to be a problem. Use the flattest three cell LiPo you can to prevent unwanted roll towards the battery, and attach it with a velcro strip so you can adjust the longitudinal CG (front to back).

Flying

Since I fly off grass, I always hand launch the Bulldog. There's room to grab the fuselage in front of the top wing, but be careful of the prop. I use an APC 10x4.7 SF with good results. The BP motor has plenty of power to climb out with a gentle toss.

For the maiden I used a 3S 1500 mAh pack, which worked but felt heavy in the air. A 1250 mAh LiPo felt better, and convinced me to order some 1000 mAh packs, which help offset the weight of the motor. With these smallest packs I set my timer at 8.5 minutes and never use more than 80% of the capacity. With very aggressive flying 7.5 minutes is still doable.

The Bulldog ready to hand launch.

Doing a harrier around the field.

Looks pretty...

... and flies great.

Flying the Bulldog makes the lousy hardware, upgrades, and modifications worthwhile. It's stable and floats very well at slow speeds. The roll rate is great as you would expect from four ailerons, and there's plenty of rudder available. Although my setup will hover and perform outside loops, it doesn't punch out strongly the way a 3D plane should. I'd suggest a lighter motor and leaving off the landing gear if you want that kind of performance.

Landings are pretty easy. I tend to keep a little power on, but you could glide in deadstick too. As I mentioned earlier, the stock landing gear is positioned too far back, and will cause the plane to nose over. You may be able to prevent this with full up elevator, but I just bent the gear forwards.

Long Term Report

I've been flying the Bulldog for four months now, long enough to get a good feeling for its durability. Overall it's pretty tough. Those nose over landings never did any harm, and the wings can handle an impact well. I don't hesitate to fly it on windy days, unlike my wood planes. The Depron tail surfaces can break though, especially the thinnest part of the rudder, next to the control horn.

Look how the motor's torque twisted the wires!

Another shot of the broken nose.

Notice the scotch tape on the Depron rudder.

Both chopsticks were inserted this far.

The one notable exception to this toughness is the nose. When built stock, it is almost guaranteed to snap in a crash. The simplest solution is to use some wood chopsticks or BBQ skewers and run them through the motor mount, down through the nose. Try to get it past the plastic landing gear mount to make the entire nose rigid. A side benefit of using chopsticks is that the motor mount will glue onto them in addition to the foam, for a stronger bond.

Conclusion

The Pitts S2 Bulldog is a lot of fun and a good flier. It's a bit expensive for what you get, and some of the hardware is junk, but it can be turned into a great plane with a little time and effort.

Be sure to check out this excellent build thread on RCGroups for additional upgrades and changes you can make, like building EPP tail surfaces.

Great Planes Cherokee Sport-Scale ARF Airplane Overview

Zero — Tue, 11 Nov 2008 03:00:00 -0600

Great Planes Cherokee Sport-Scale ARF is a 60 in model which could be rigged with either glow or electric power. This scale model is ideally suited to those interested in a scale-looking low wing model and is a great step-up after your first trainer. Being an ARF, they claim 4-6 hours of assembly and your off to the field. This model will perform the basic aerobatic maneuvers and should be an ideal first low wing airplane for the serious RCer.

The cockpit area lifts off providing access to the electrics

Construction features and details on this model are no in short supply. Great Planes has a real winner on their hands with both a great looking scale plan in the Cherokee ARF as well as what should be a good performer when using electric or nitro propulsion. Great Planes explains all the great features on their website, but some of the highlights include: a bolt-on wing and tail for easy assembly and transport, tricycle landing gear, fiberglass wheel pants look great while providing low drag, and with a 5 channel radio you can even operate the included flaps. You will need at least a 4 channel radio (5 channel for the flaps), servos, and electric or nitro power to complete this model.

Specifications

Can be fitted with Electric or Glow power

Wingspan: 60 in (1520 mm)
Wing Area: 606 in² (39 dm²)
Weight: 6.75-7.25 lb (3.1-3.3 kg)
Wing Loading: 26-28 oz/ft² (79-85 g/dm²)
Length: 46 in (1170 mm)
Requires: 4+ channel radio system (5-channel required for operational flaps) w/4-7 standard servos
Electric Power Requirements:
- ElectriFly™ RimFire™ 42-50-800 Out-runner Brushless Motor (GPMG4700);
- ElectriFly Silver Series SS-60 Brushless Electronic Speed Control (GPMM1850);
- 18.5V 3200mAh LiPo battery (GPMP0622 or GPMP0623);
- propeller (10x5E or 11x5E)
Glow Power Requirements:
- 2-stroke .40-.46 cu (7-7.5cc) or 4-stroke .52-.56 cu in (8.5-9.2cc) engine

All the components of this ARF

For more information, check out the Great Planes website.

Century Swift 3D 6-Channel 2.4Ghz RTF Overview

Zero — Mon, 10 Nov 2008 03:00:00 -0600

The complete package

Swift has produced an excellent 30 size electric ready to fly helicopter. This is a fine model and has been test flown and ready for the experienced 3D flyer or with training gear would be an excellent choice for the first single blade helicopter. Similar to other 30 size models on the market, but it also includes a 2.4Ghz 6-channel radio which will provide awesome Spread Spectrum technology so you don't need to worry about someone on the same frequency taking out your heli. With a length of 105 cm, this is a good size to get started and Century Helicopters produces some nice quality models so you are backed by a company with good access to parts for repair. This is critical for any helicopter flyer.

Century Swift 3D 6-Channel 2.4Ghz RTF

As far as the details and construction, this isn't an all graphite model; but being a ready-to-fly helicopter it has good quality. Also, for a beginner composite plastic parts are much more forgiving in a crash and many new pilots make the mistake by trying to learn on a fancy graphite model that is much more expensive to repair.

Features

Powerful 550 sized outrunner motor
High speed tail mounted servo
heading lock gyro
nicely integrated tail system
eCCPM control geometry
Thrust bearing supported blade grips
2.4 GHz control radio
1700-1800 rpm for blades - easy for beginners to control

Specifications

Century Swift 3D 6-Channel 2.4Ghz RTF

Main Rotor Blades: 520mm
Tail Rotor Diameter: 21cm
Length: 105cm
Height: 34.4cm
Weight: 1.56kg
Speed Control: 75/95 Amp
Motor: 1440kV
Battery: 4S Li-Po 20C/30C
Pinion: 10 tooth
Head Speed: 1600 - 2100 RPM
Radio System: Elite 2.4GHz 6 Channel
Flight Time: 12-15mins
Charger: Standard AC Wall Charger

For more information, check out the Century website.