Great Planes Giant Aeromaster ARF Review with Fuji 43 Gas Engine!

Dick Pettit walks down nostalgia lane, remembering his 1996 review of the Giant Aeromaster Kit, then comparing it to the newest Aeromaster...the Giant Aeromaster ARF with a Fuji 43!

Great Planes Giant Aeromaster ARF and it's builder (I'm the one in the fancy shirt)

Introduction

First landing, slow, smooth and only one tiny bounce
First landing, slow, smooth and only one tiny bounce
Spec Advertised Measured
Wingspan, Each:73"73"
Wing Area:1880 sq. in.1777 sq in
Fuse Length:63"63.5"
Weight:16-18 lb17.5 lb (280 oz)
Wing Loading:22.9 oz/sq. ft.22.9 oz/sq ft
Servos:See text for details6 Hitec HS4775BB
1 HS635HB
1 HS4255BB
Transmitter:4+ chFutaba 7C PCM
Receiver:4+ chFutaba PCM
Prop:n/aAPC 20x8
Engine:1.6-2.3ci glow
1.7-3.7ci gas
Fuji Imvac BT43EI

Additional Equipment: Tru-Turn 3" Black Anodized Spinner
4c 1100mA Ignition battery

Manufacturer:Great Planes
Available Online From:Tower Hobbies

Then....

Here's what I wrote way back in 1996 when I built the kit version of the great Planes Giant Aeromaster:

"Biplanes have always held a special place in my world of model aviation, and I'm sure that they are many other modelers’ favorites also. A number of years ago, before I was even interested in R/C models and quite possibly before many of you were even born, Lou Andrews designed a small biplane model that could be easily built and flown by the average modeler. It was designed to be powered by a .40 size engine, used standard radio components, was small enough to be carried in normal vehicles and could be built with 3 different wing plan forms. This was the famous Aeromaster biplane that was built and flown by thousands of pilots around the world. The wings were held on by rubber bands, as were the main landing gear legs. Aeromasters have been boring holes in the skies for a long time. Then, about 15 years ago, Great Planes bought the rights to produce the kits, to which they made a number of updates, including bolt-on wings and main gear, a clear canopy and a round cowl. These changes were probably added to a large majority of the original Aeromaster models during the course of their careers. The Super Aeromaster evolved into a .60 size aerobatic biplane that could be decorated to resemble many scale planes, like the Jungmeister and the Waco. It, too, was a very nice model to build and fly."

"But, what about the Giant Scale modelers, like me? We had been asking for a larger version of the Super Aeromaster for a long time, wanting to fly a model like the Super Aeromaster, but in a larger, more powerful version. I suppose Great Planes Model Manufacturing Company had heard enough whining from those Giant Scalers, and they had their design team draw up a Giant size version of the Super Aeromaster, naming it, of all things, the Giant Aeromaster. With its 73 1/2" wingspan, room on the nose for a large gas engine and all the great flying characteristics of the original Aeromaster, the Giant Aeromaster is the subject of this Product Review."

It was a pretty nice flying airplane, capable of most standard aerobatic maneuvers, but it really excelled in low and slow flying, something I really enjoy too. It was easy to keep up with, with gentle landings and graceful airborne maneuvers being it's strong points. I used a magneto equipped 41cc gas engine, but others were powered by larger, more powerful engines. They exhibited better vertical performance, but they still flew just as fast horizontally as mine.

And Now...

Now, 10 years later, Great Planes has kept up with the trends of the times and introduced the Giant Aeromaster ARF, with the same wingspan, length and power requirements as the original, but now allows the modeler to get the plane into the air in hours instead of weeks. I arranged to get one of the Giant Aeromaster ARFs for this review and also ordered one of the new Fuji BT-43EI engines, as suggested in the manual.

I also found out that the Giant Aeromaster is also being made available in an RTC (Ready to Cover) format. This means that the builder has the option for just about any color scheme they want, from Pitts Special to Christen Eagle to Jungmeister, just let your mind go wild.

Kit Contents

Taking the cover off the 56" by 14" by 15" shipping box, we find a plethora of goodies...

The Main Components --

  • a set of upper and lower wing halves,
  • a sleek fuselage assembly,
  • all the appropriate tail surfaces,
  • The usual detailed, excellent Great Planes Instruction Manual

And the hardware included:

  • Painted fiberglass cowl and wheel pants,
  • formed and painted aluminum main landing gear,
  • tail wheel wire and bracket,
  • main and tail wheels with collars,
  • aluminum cabanes and N struts,
  • fiberglass engine mount for a large glow engine
  • fuel tank with lines for both glow and gas,
  • point type hinges,
  • all control linkage materials,
  • formed plastic canopy,
  • pilot figure,
  • all necessary nuts, bolts and screws for assembly,
  • self-stick graphics sheet

Looking closer I found that all the control surfaces are hinged using a form of point type hinges similar to the popular Robart design. This makes for a strong but flexible hinging method that will stand up to years of normal flying.

Decisions to Make

As I'll mention in the assembly area, there were several choices to be made...

  • Engine (glow or gas, etc);
  • Two aileron servos or four;
  • Reverse one elevator servo, or use radio programming/mixing (I had a reversed servo on hand);

Assembly

I'll be using Pacer Brand adhesives to assemble the Great Planes Giant Aeromaster ARF, including their epoxies, ZAP instant adhesives and Hinge Glue. With these adhesives, and any others you may chose to use, please provide proper ventilation during their use. Also take sure that proper ventilation is used when cutting and sanding fiberglass parts such as the cowl and wheel pants.

The Giant Aeromaster is no different than most ARFs in having a few wrinkles, and it took a little more than an hour to run the heat gun over the Top Flite Monokote to bring up the bubbles, shrink them, and then press the covering back down to the surface. Be extra careful when heating any of the trim covering because it may have a different shrink rate than the underlying MonoKote. Also, take care not to keep the heat gun aimed over one place for a long time because, contrary to popular belief, MonoKote can develop large holes when heated beyond it's heat tolerance point, especially over open structure. I rate the covering job on the Giant Aeromaster to be average.

Preparing the Wings

I found that the pre-drilled hinge holes were the correct diameter, but several had to be drilled deeper. Also the use of a countersink bit will open up the area around the hinge pivot point, allowing the aileron gap to be held to a minimum. Lastly, take care when applying the hinge glue or epoxy, since it can dribble out the balsa hinge blocks inside the wings and spoil the appearance of the covering. Use only as much adhesive as needed.

I cut the servo openings through the Monokote with the tip of an old soldering iron which both cuts the material and seals the adjoining material to the wood structure. The builder is given an option to use either two or four aileron servos, either of which is adequate for a plane like this one. If two servos are used, the lower ailerons are directly driven by the servos and joiner rods will connect the lower ailerons to the upper ones. I have had some difficulty establishing geometrical equality when operating ailerons in this manner, so I chose to use four servos, each driving it's own individual aileron. But you still have the choice since all the parts necessary for either version are in the kit box.

With the panels joined and the tape removed, we next assembled the control linkages for either just the lower wings or both of them, if we chose to use four aileron servos. The control horns are attached to each aileron using sheet metal screws that do not go all the way through the surfaces. Be sure to insert each screw, remove it and apply a drop or two of thin ZAP to each screw hole to harden the threads.

Mounting the Tail a Touch Early

I jumped ahead, knowing that the stab and fin need to be aligned to something before gluing them into place. The book says to align the stab to the building board but I chose to align it to the wing. In order to get the fuselage off the board, I installed the main landing gear, wheels and wheel pants, making sure that good building practices were followed. These included the use of thread locker on the mounting bolts and wheel collar set screws and filing or grinding flat spots on the axle shaft where the wheel collars are to be places. A drop of oil on each axle wouldn't hurt to keep the wheels turning freely.

On a plane of this size and weight, I don't care for the type of tail wheel assembly that is glued tightly to the rudder since it places a lot of vertical load on the tail structure. One of the popular leaf spring tail wheel assemblies will work fine, but I decided to give the stock unit a try. You can make up your own mind as to what you want to use.

Either one elevator servo needs to be reversed or that function needs to be dealt with in the transmitter. I had a reversed servo waiting for such a project.. I then noticed that there is barely enough room for the two elevator servos, a single rudder servo and the throttle servo on the hardwood mounting rails. Careful planning must be considered before finalizing the servo locations. The line drawing in the manual does not represent the actual size of the servos.

Time for Gas! or At Least the Engine....

Engine installation is next and Great Planes has thoughtfully installed the blind nuts in the back of the fuselage to fit both the Fuji 43EI gas engine and the plywood mounting plate for two cycle engines. If other engines are contemplated, I hope the builder has small hands since there is barely enough room for a child's hand inside the fuselage at the firewall.

A small opening had to be cut in the front of the lower hatch area to allow the ignition wiring to get to the engine.

The fuel tank assembly comes with plumbing suitable for both gasoline and glow fuel. The tank clunks are huge, but their weight will just about guarantee that they will always be in the fuel supply.

The completed fuel tank was then installed in the fuselage and this was the hardest part of the assembly so far. Trying to get two pieces of neoprene fuel tube through a small hole in the tank former while the tank itself was in the way was extremely difficult, but it can be done.

The tank vent and carburetor lines come out of the fuselage through a hole cut in the top of the firewall. The vent line then has to get past the engine, which can get very hot while running, without touching it. I used a scrap section of brass tubing fastened to the fuselage behind the engine to act as the vent line. Th carb line is easier to install since it wraps around the carb and directly into the carburetor fitting. I put a Tee in the carb line to be used with a DuBro Fill-It fuel filler assembly that will be mounted on the cowl.

The throttle linkage was next, and there was already a pushrod tube installed in the fuselage that worked just about perfectly with the Fuji 43EI. I suspect it will also work with the recommended glow engine, but possibly not for other engine choices. The throttle pushrod itself is a plastic tube which will not transmit interference from the engine ignition system back to the radio system. If the stock throttle on the carburetor is used, the pushrod assembly has to have a 180 degree bend to attach to the relatively short arm.

The plastic clevis is a nice touch, but the clevis pin is considerably smaller in diameter than the hole in the throttle arm. This causes excess play in the throttle linkage and this is not what I wanted.

The stock throttle arm was removed by grinding the peened edge of the throttle shaft and gently twisting the arm off the shaft. The spring between the arm and the carburetor was saved for use with the new arm. I used a spare nose wheel steering arm, drilled the hole to fit the throttle shaft, put an EZ connector on the end and connecting the throttle linkage. This time there was no play or excess motion.

Mount the Cowling

Mounting the cowl isn't all that difficult, but the photo and text of the location of the mounting blocks don't match each other. Go by the photo, not the text. I added a few wood dowel pegs tl each mounting block for a bit more strength.

Additional holes for the muffler outlet pipes, the spark plug and an enlarged opening behind the cylinder head had to be cut.

The Easiest so Far -- Mounting the Wings

The installation of the wings comes next and it was the easiest process I found so far. (by the way, all the holes are drilled and the blind nuts are in place)

In this order,

  • mount the lower wing,
  • bolt on four strut brackets,
  • bolt on four more strut brackets to the upper wing,
  • bolt on cabanes to upper wing,
  • bolt interplane struts to lower wing brackets,
  • place upper wing over interplane struts,
  • bolt them together,
  • put the Aeromaster on it's nose,
  • make sure the wings line up with each other and tighten all bolts.
  • Mark and drill holes in fuselage for cabanes.
  • Insert screws, remove and harden threads with thin ZAP, and reinstall screws.
  • Done!

The upper and lower wings measured within 1/16" or each other to the tips of the stab, which is close enough for me. The only change I made was I swapped the Phillips head screws used for mounting the struts and cabanes for Allen head bolts since these will be the ones that will have to be removed to disassemble the plane.

If the builder decided on aileron servos on the lower wing only, the kit comes with aileron joiner rods, clevises and horns that are now installed to make the upper ailerons move correctly.

Final Steps

CG OOPS!

The balance point shown in the manual is wrong and is corrected by an addendum and on the Great Planes web site. The correct balance point is 2 1/2" back from the leading edge of the LOWER WING. Mark this point on the top of the lower wing on each side of the fuselage, turn the completed plane over and balance at these points. There's a +/- 3/8" range from this starting point, but I like to get the plane to balance where the manufacturer suggests and go from there.

Lots of great little details in this build. The fuselage even has some plywood on each side into which the switch can be mounted.

I was pleased to find out that the total weight of the Giant Aeromaster, ready to fly, minus fuel, was 17.5 pounds. That's less than the high end of the weight range, but with a wing loading of less than 23 ounces per square foot, this plane should fly just fine. If the lighter two stroke OS 1.60 engine is used, there may be a need for some nose weight due to the much lighter weight of this engine compared to the Fuji 43EI.

Speaking of the Fuji 43EI, I took the completed airplane out to the backyard engine testing area and filled the tank with some gas mix. After choking and flipping the prop about 10 times, the engine coughed once and started on the third flip after the choke was opened. After allowing the engine to warm up a bit, I revved it up to find that the high speed mixture was within 1/8 rich of a turn of being perfect. The low speed needle needed a little tweaking, but it'll now idle at 1500 RPM and turns the APC 20-8 wide blade prop at almost 7000. That combination provides more than 21 pounds of pull on my digital fish scale and will be plenty to get the Aeromaster into the air.

Spinner Color?!?!

I heard that Tru-Turn was offering a new service with their spinners. They now have the capability to anodize many of their spinners and hubs in several colors, including red, gold, black and blue. These colors will probably not match your paint job or covering, but a beautiful contrasting colored spinner will surely set your model away above the average. I got a 3" standard spinner which they anodized jet black and it really looks good on the nose of the Giant Aeromaster. Get more information directly from Tru-Turn .

Flying

I took the Giant Aeromaster to "Area 51" on a cool morning that promised to provide good flying conditions. The plane was assembled, taking about 10 minutes for all of the nuts and bolts to be installed, and a bunch of ground photos were taken. My assistant test pilot, Rick Cawley, took the controls of the video camera while I handled the transmitter for the first flight. The Fuji 43EI started up just fine and the radio range check showed that everything was in working order. I made a back and forth taxi run while waiting for Rick to get in position at the far side of the field (better light for picture taking from that side) and everything was ready to go.

Take Off and Landings

I increased power slowly and the Giant Aeromaster began to roll briskly down the runway. Only a slight amount of right rudder was needed to keep it headed in a straight line. After several hundred feet of rolling and still at half throttle, the Aeromaster lifted off the ground as if it were on rails. There was no lack of power and flying speed even at this power setting and I trimmed it for hands off level flight.

But I had been in the air almost 15 minutes and I had to set up for a landing. With power reduced and lined up on the main runway, the Aeromaster seemed to float down towards the grass strip. With about the last foot of altitude between the plane and the ground, power was cut and the plane just bounced gently and slowed to taxi speed. I then realized that there was still plenty of gas in the tank, so I taxied back to the opposite end of the runway, increased power and took off once again, this time at full throttle. The Aeromaster jumped into the air and I realized that there was even more power available than when I first took off. I'm not saying that the Aeromaster has unlimited vertical performance, but it'll climb up to a high altitude in just a blink of an eye.

Soon I landed again, taxied back and made yet another takeoff, just to see if they could be made any better. The third landing was probably the best of all, but there was still just a slight bounce when touching down, but this was later corrected by holding in just a small amount of power until the wheels were on the ground. I taxied the Aeromaster back to the pit area for refueling and some inspection.

Rick also really enjoyed his stick time with the Aeromaster, particularly landing. In his hands, there was no bounce at the touchdown, but he was holding in a little power, like I said I would do.

Basic Aerobatics

Early in the first flight, I took it up to a comfortable altitude and increased power to almost full, and did a beautiful axial roll. Next came a great big loop and the Aeromaster never lacked power, even at the very top of the loop. Back at half throttle, I cruised around a bit and then decided to see what low speed response would be like. The Aeromaster just flew a lot slower with absolutely no loss of control response. Back on the power, I climbed to altitude again, cut the power and let the nose fall, breaking into a 2 turn spin. It entered the spin perfectly and came out within a quarter turn of my neutralizing the controls. This was a great flying model.

I did some more basic aerobatic maneuvers like a stall turn, a Split S and some Cuban 8's. The stall turns were absolutely perfect and it looked like the Aeromaster was turning on an axle.

Rick's turn! Rick did a slow taxi run and then took off just as smooth as could be imagined. I said to "exercise it a little". He then proceeded to fly the Aeromaster as it was designed to fly, sport aerobatics. Three axial rolls in a perfectly straight line, several loops, one after another and some knife edge passes were done in no particular order.

He landed and took off again and remembered he hadn't done any inverted flying, so he rolled the Aeromaster onto its back and proceeded to fly several circuits of the field area upside down (see the video). He later said that very little down elevator was needed to maintain inverted flight and the Aeromaster didn't need much elevator correction when flying in knife edge. Rick landed again and immediately took off in the opposite direction. Why? Probably because he didn't want to waste valuable fuel on just taxiing. This time, more aerobatics, and every maneuver seemed to be smooth and stable with no hint of marginal control.

After the next landing and refueling, I got out the video camera and filmed Rick flying the Aeromaster yet again. He was really enjoying himself and the plane performed beautifully. More aerobatics, low passes and sweeping turns, all punctuated by loops, rolls and inverted fly-bys led up to the last landing of the day. And this one was probably the best one all day.

Overall Flight Comments

Rick and I took a seat in the shade of the shelter and discussed what he thought of the Aeromaster. Every other sentence he spoke was something like "I really like flying that plane". He said the Fuji 43EI engine provided plenty of power, although we both said that there would be many builders that would want to use a larger engine. We thought that the Fuji did perfectly well. Rick seemed to think that the control throws were just about perfect, even though he never used high rates at all, even on the rudder during knife edges. I had set up the throws according to the numbers in the manual and they seemed to be a great starting point. Rick also said that the slight bouncing on my landings were the result of not holding in a little power just before touchdown, which he did, as was seen in his almost perfect landings. We were both happy with the results of that day's flight tests. We had put almost an hour of flight time in the Aeromaster and had enjoyed every minute of it, even with the split landing gear (more to follow)....

Back at the shop…

On my first landing, Rick had noticed a problem with the main landing gear. The gear legs have an aluminum center section that is laminated with what looks like soft balsa wood and is painted with an epoxy type paint. When the gear legs flex, even very slightly, the balsa cannot bend with it and had delaminated from the aluminum. One side was split front and back half way down, and the other one was split about a quarter way down. The split laminations would in no way reduce the load carrying ability of the main gear legs, but it did look pretty bad. I had some yellow electrical tape in my tool box and I wrapped the tops of both gear legs tightly to keep them from delaminating any more.

I fixed the main gear that afternoon at the shop by cleaning the laminations well, applying a drop or two of thick ZAP to the joints and clamping them together. This would certainly be enough to hold them together, so I wrapped the top half of each leg with fiberglass strapping tape, the stuff you hold packages together with. I applied one wrap to the lower part, two wraps to the middle and three wraps to the top, trying to keep them as even as possible. It looked OK, but not as good as I wanted it to be, so I then applied a covering of white Monokote to the tape, just to hide the wrappings. It still had a few ridges showing, but from a distance it was much better.

I "field tested" the gear in the back yard by dropping the fully assembled Aeromaster from a height of two feet above the grass. The strapping tape held perfectly and I got to thinking that maybe the tighter gear legs would keep the Aeromaster from bouncing so much. Or maybe I should just learn to land it perfectly like Rick did....

Great Planes indicates that they've not seen or heard of this problem previously, and will check their stock. Hopefully the problem was unique to my model...

Photo/Video Gallery

Downloads

Conclusion

The Giant Aeromaster ARF form Great Planes is a welcome addition to a fine line of ARF planes. It is not an all out 3D monster, it'll probably never win any scale competitions and it will certainly not be flown in any park. What it WILL do is fly smoothly and gracefully, slowly and faster, high or low, and do this with style. It took me about 12 hours to assemble, but you mileage may vary. The Fuji 43EI engine provides all the power the Aeromaster needs to fly in this manner, and it starts easily and runs smoothly, so what more could you ask? Other than the small problems during assembly that could be overlooked easily and even the split laminations on the main gear legs which was a looks issue not structural, the Great Planes Giant Aeromaster ARF is a wonderful plane to assemble and fly.

It will make any pilot feel proud to be its owner...I know that I am....

Positives:

  • Very complete kit,
  • all items suitable for plane of this type and size,
  • excellent flying plane -- stable, aerobatic
  • great sport plane

Negatives:

  • Wing area more than 5% smaller than advertised,
  • would've liked more room to ease installing 4 servos side by side in fuselage,
  • cut out for tank vent line left line extremely close to hot engine,
  • main gear legs delaminated after first soft landing.
Last edited by AMCross; Oct 10, 2006 at 07:36 PM..
Thread Tools
Dec 31, 2006, 10:30 AM
Registered User
Thanks for your article. I am in the process of buying one. I have been flying the orginal Aeromaster by Lou Andrews for many years, since in the mid 1970's. That was a real winner for me. Thanks again


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Article Great Planes Siren Hotliner ARF Review Andy W Electric Sailplanes 4065 May 13, 2020 06:30 PM
Article Great Planes Wright Flyer ARF Review Michael Heer Parkflyers 24 Apr 28, 2019 09:15 AM
Article Great Planes Giant Ultimate ARF with Fuji 43 Gas Joint Review with RC Report pettit Fuel Plane Talk 6 Apr 25, 2007 05:44 AM
Discussion **NEW** Great Planes Giant Aeromaster ARF Jim T. Graham Product Announcements 0 May 30, 2006 10:45 AM
Article Great Planes Spirit 100 ARF Review Tim Wolff Sailplane Talk 0 Nov 24, 2005 02:00 AM