Reviews

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.

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 »

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.

LADO 60-1 Electric Retract Review

Paul Osinski — Wed, 08 Oct 2008 22:15:14 -0500

The Aero-Modeler traditionally had two choices for their models if they needed retractable landing gear. Pneumatic air and servo assisted mechanical retracts. Now our third choice is electric. LADO Technologies has developed an extensive line of electric retracts. For this review, I will be critiquing the 60 sized, 85 degree drop in replacements for Hanger 9 planes.

First impressions:

Underside with integrated controller board

When I opened the box of my first 2 LADO retracts, my first thought was that of incredible craftsmanship. The outside casing is machined from two blocks of aluminum that fit together with pin point precision. The control circuit board is integrated into the bottom of each retract. The lead wire has a universal connector of high quality with a custom rubber seal to hold them in place. Located on the inside of the brass pivot stud, are stainless steel setscrews for fastening the strut. On the top side of the retract units is an adequately thick mounting plate with countersunk holes for screwing your retract to your wing mounts. The casings and circuit board are held together with high quality socket head cap screws. As the units come shipped with the mechanism set at a 45 degree angle for testing before they leave the factory, the brass jackscrew can be seen from the opening. This model retract can be ordered with 5/32 or 3/16 opening for your struts. The total weight of a pair of these units is just a tad over 6 ounces. In my opinion, a well built piece of equipment.

Installation:

3/4 view

Installing the LADO retracts are very straight forward. Fit them to your wing with your strut trimmed and aligned and screw them down. Join the lead wires with a Y adaptor and plug the end into your channel 5 pins on your receiver. Turn on your transmitter and receiver and flip the switch. The units are powered by the receiver. The LADO’s come to life with a sweet motor sound, then a forceful locking sound can be heard as the built in motors labor slightly. Current draw is .3 Amps during movement and .5 Amps for about 1/4 second during locking. Movement is slow compared to mechanical or air retracts. Using a regulator set to 6 volts, it took about 6 seconds for them to fully deploy. Great for modelers that want realistic retract speed. You can even purchase an accessory board to replace your Y adaptor that will stagger the retracts for even more realism.

Practical operation:

Side view

I installed my LADO’s in a 9 pound War Bird with 3/16 spring struts. Simply put, they work flawlessly. I start to retract the gear right after the first turn after liftoff so I can watch the gear slowly tuck under the wing as the plane is flying level above the runway. What a joy to watch! I do the same for landing as well. Special attention should be paid for landing. It is going to take around 6 or 7 seconds for the retract gear to lock down so plan ahead to avoid any mishaps. On landing, the retracts are solid. Not a single budge.

Durability:

Side view with wire strut and wheel

I can not say I have had hundreds of flights using these retracts. I will however share an experience. On my maiden flight of my War Bird, one of the struts got a tad bent on landing. Since I had blocked my gear mount bay with bass and plywood I figured it would be alright to try to bend the strut back without taking out the retract or causing any damage to the wing. I retracted the gear till the strut was about at 10 degrees to the wing and turned off the receiver to stop the retracts from further travel. I then grabbed the wheel and tugged till the strut was strait again. After that I cycled the retracts several times to be sure they would be fine. Not a single problem then, or ever since. From that experience, I am convinced the durability of these units is far more than need be.

Maintenance:

According to the manufacturer this model may need a little light machine oil after 2 years.

Overall conclusion:

If you want worry free retracts this is the way to go. Imagine not having to worry about a stalled servo, bent rods, having to pump air into your system or concern yourself about a loose air line. LADO retracts are built with the highest quality standards for years of service.

Company history:

Lado Technologies

Lado Technologies is owned by Doug Pientak. Located in Orville California. Like many great company’s it all started in a big garage.

The idea for electric retracts was a result of a conversation with Kalvin of Keleo Creations. He wanted some trouble free retracts for a plane he was working on. Doug, an Aero-Modeler himself thought it was an awesome idea as he was not happy with mechanical or air retracts either. Early in the 1 ½ year development, Doug realized that a Jack Screw design was the best way to design the new equipment.

Doug is an Electrical Engineer with a background in Product Development. With that experience it still was not a smooth beginning. “I am not a machinist by trade”, as a result he had to learn how to work a milling machine. “It was very frustrating in the beginning because I started with an old machine”. In retrospect, the end product was worth the frustration.

Much has happened in the last three years for LADO Technologies. Just after 8 months of development his Father, Larry partnered with Doug. In September of 2007 the company moved to its current facility. Shortly after the move a new lathe was purchased to help with production. The beginning of 2008 Doug’s wife, Lanae joined the team to help with electronics assembly, bookkeeping and to answer the phone. A HAAS Vertical Mill was purchased with high volume capabilities. “The HAAS is a joy to run. Simply input the parameters and push the button” Doug told me with obvious excitement in his voice. The latest change was made on 8/5/08 which is LADO’s web site. It has a new look and is much more user friendly than the original. “An account must be setup and has many advantages for the customer with this feature”. The improvement to the web site lets the customer get actual shipping costs, lets the customer check the status of their order and if an order is shipped that has a tracking or delivery confirmation number, the buyer can get that as well. If an item is not in stock the web site will not let you place an order. This eliminates any backorder problems. Another one of the site’s great improvements is the ‘Gear Finder’. This feature lets you match your plane or gear with the appropriate LADO equipment. Doug informed me that the only thing missing from the web site is the LADO Guarantee. He will Guarantee LADO Retracts for a one year period, including parts and labor.

During my phone interview with Doug, he also told me: “Business is booming, the economy has had no effect on the volume of orders”. Building LADO retracts are his only source of income. LADO Technologies is actively developing new products and will add them to the product line as they become available. The LADO facility also has a company mascot, an African Gray Parrot. Doug, how about a picture of your mascot on your site? Aero-Modelers, as you know have great senses of humor.

My overall conclusion:

LADO Retracts are well designed and durable equipment well worth the price. The owner of this small business is dedicated to Aero-Modeling as well as producing a quality product.

But wait, there’s more!

LADO Technologies produces a wide variety of retract products. Products like; Actuators that transform your air retracts into electric and controller Actuators. Check them out today.

Dualsky XMotor Review

Daniel Switkin — Thu, 28 Aug 2008 08:52:18 -0500

When looking for a new power source for my RC Bug, I ran across a very unusual motor from Dualsky. This tiny outrunner contains a 6 amp brushless speed controller in the motor housing. That means you get a matched motor and ESC with no hassles of soldering bullet connectors or checking which way the motor spins, and less wire clutter when installed. Read on for our review.

FMA Direct Cellpro 10s Charger Review

Daniel Switkin — Sat, 02 Aug 2008 14:10:52 -0500

The FMA Direct Cellpro 10s is a balancing lithium battery charger, capable of charging a single battery up to 10 cells, or two batteries simultaneously up to 5 cells, with power up to 10 amps. It can handle lithium polymer, lithium ion, and the M1 lithium cells from A123 Systems. Let's dig in and put it through its paces.

Align T-Rex 450S Build Notes

Daniel Switkin — Tue, 13 May 2008 21:34:23 -0500

The Align T-Rex 450 series is perhaps the best known of the mini-size electric helicopters. Many reviews are available online, including this thorough one at T-Rex Tuning. In this article I'm going to sum up the positive and negative experiences I had building the 450S aluminum kit, and include a list of tips to help you out.

Eagle Tree Systems eLogger V3 Review

Daniel Switkin — Wed, 02 Apr 2008 21:50:11 -0500

The eLogger V3 from Eagle Tree Systems is an in-flight data logger which continuously records volts, amps, watts, and milliamp-hours to enable pilots to analyze the performance of their electric power systems. In addition, it supports a wide variety of optional sensors to record altitude, airspeed, component temperatures, RPM, and more.

BUKU Self-Tuning Exhaust System Review

Sean — Wed, 12 Mar 2008 04:57:49 -0500

In the RC world, one of the things that we think about most is getting the absolute best power from our vehicles that we can. One element that is crucial to having the best power possible from your vehicle is a well matched exhaust system that can complement the power of your motor. Alot of times, you can have the best motor out there, but if you haven't paired it with a good exhaust, you can kiss all the horsepower and abilities of your motor goodbye. On the flip side, if you have a old motor, or a motor that does not create alot of power, you can wake it up or give it a good kick in the rear by adding a great exhaust. The question is, which one? This is where the Buku comes in.

ElectriFly Reactor 3D Review

Daniel Switkin — Mon, 28 Jan 2008 19:34:00 -0600

The ElectriFly Reactor 3D from Great Planes is a 41" wingspan, mid-wing acrobatic plane. It is aimed at intermediate and expert pilots looking for a 3D-capable park flyer. With huge control surfaces and no dihedral, I was really excited to build this plane and get up in the air.