Archives for September 2013

Two New Videos Added!


I added two videos to the website this past week.

Top view of the Ares Tiger Moth 75 RTF biplane

Top view of the Ares Tiger Moth 75 RTF biplane

The first one is on the Ares Tiger Moth 75.  Ares did a superb job creating this remarkable RC model. The plane looks great and truly captures the character of the original aircraft. The model weighs an incredible half ounce yet has three channels of control.

The Tiger Moth comes completely assembled. The main components, to include the landing gear, lower wing, battery and four wing struts are all held in place by tiny magnets. With this scheme, any inadvertent bump causes these components to simply pop off with no damage.

As a matter of fact, you can see an accidental midair at the end of the video. The Tiger Moth was reassembled and back in the air five minutes later.

And did I mention the Moth flies great?

Front view of the ParkZone Mini Vapor

Front view of the ParkZone Mini Vapor

The second video is on the ParkZone Mini Vapor. The Mini Vapor is, from my calculations, the lightest ready to fly RC model you can purchase. The Mini Vapor weighs just a third of an ounce and has three channels of control.

The Mini Vapor has large all-moving control surfaces for positive flight control. The model is exceptionally well made with every attention to detail to keep things light.

The model normally maneuvers at a 45 degree nose high pitch attitude during slow flight. The Mini Vapor is a fun, easy and stable model to take in the air.

ParkZone Mini Vapor First Impressions


I flew my new ParkZone Mini Vapor for the first time this past Monday. See my write up here.

Front view of the ParkZone Mini Vapor

Mini Vapor front view

I am extremely impressed with this remarkable little model. It flies and handles like a much larger and heavier aircraft. The Mini Vapor has plenty of power, exhibits balanced controls and is great fun to maneuver close in.

The Mini Vapor has a wingspan of 8.7 inches and weighs a mere 8.5 grams. I am quite sure this is the lightest production ready to fly RC model airplane available.

The Mini Vapor uses three channels of fully proportional radio control. Two linear servos connect to the all-moving rudder and elevators for positive control authority. The tiny brushless motor is operated by the receiver’s electronic speed control.

Mini Vapor demonstrating close in flight

Demonstrating close in flight

Design attention to detail clear as you examine the aircraft. All efforts are focused on keeping the weight to an absolute minimum. Lander gear placement, wing post attachment tail surface connections are delicate, yet secure. There is even an airfoil shape built into the film covered wing.

The Mini Vapor can takeoff from the ground or start flight with a hand launch. The model is very maneuverable and has a crisp response to control inputs. Nose high slow flight is the Vapor’s forte. With practice, hovers of a sort can be demonstrated. An occasional loop/flip can be flown as well.

The Mini Vapor is an affordable addition to anyone’s indoor flying fleet. The model’s slow flight characteristics make for a great trainer. You cannot go wrong with this fun and ready to fly ultra micro indoor RC model plane.

Ares Tiger Moth First Impressions


I flew the new Ares Tiger Moth 75 this past Monday. See my write up here.

Tiger Moth 75 in flight

Tiger Moth in flight

I am very impressed with this remarkable ready to fly model. The Tiger Moth flies and handles like a much larger model aircraft. The plane has plenty of power and the controls have a positive feel.

The Tiger Moth uses an innovative combination of a linear servo for the elevator combined with a magnetic actuator for the rudder.  This attention to detail results in the lightest weigh possible for this semi-scale flyer.

Top view of the Ares Tiger Moth 75 RTF biplane

Tiger Moth top view

The Tiger Moth uses powerful tiny magnets to hold the structure together.  Magnets keep the landing gear, bottom wing, four struts and lipo battery in place.  This is a wonderful feature as the components simply pop off if you have a bump or hard landing, preventing damage.  And it takes just a moment to put everything back together.

The Tiger Moth can takeoff from the ground or start flight with a hand launch. The model is  maneuverable and has a crisp response to control inputs.  The larger rudder provides for tight turns with no indication of a stall.

The Tiger Moth is an affordable addition to anyone’s indoor flying fleet. You cannot go wrong adding this ready to fly micro RC plane to your model collection.

Clark Y and Moskal Blackburn


My latest page is a discussion of the Clark Y airfoil with instructions on how you can draw this useful wing rib shape for your model plane designs.

Three views of a Clark Y airfoil showing different lengths

Three views of a Clark Y airfoil showing different lengths

The Clark Y was developed in the 1920s for general purpose aviation. The airfoil provided good handling and predictable stall characteristics, design elements sought in those early days of flight.

It turns out that the Clark Y is a great choice for radio control model airplanes. The airfoil is well suited for model airplane construction due to its flat bottom. Wing ribs can be placed directly on a flat building board.

The Clark Y has a good amount of depth to accommodate wing structure, to include components such as aileron servos or retractable landing gear.

Steve Moskal's Blackburn under construction (copyright

Steve Moskal’s Blackburn under construction (copyright

As with full scale aircraft the Clark Y provides good handling characteristics and gentle stalls. I use the Clark Y for all of my model aircraft designs.

For antique flyers such as the Blackburn or the Fokker Spin, with their under cambered airfoils, I used the Clark Y outline to prepare the wing rib shape with a variation. I left out the full depth of the ribs per the original wing design. The planes fly fine, yet retain the unique look of aircraft produced during the first decade of flight with their thin wing sections and under camber layout.

You really cannot go wrong with using a Clark Y for a sport radio control model plane.

The page shows detailed information on how to plot out the airfoil. The diagrams show the calculations that are needed. You can draw the airfoil by hand or use a program such as TurboCAD. A CAD program is a big help as you can easily copy and resize the airfoil to fit new designs.

Finally, there is a fascinating series of posts on the RC Groups forum by Steve Moskal on his build of the Blackburn. Check out the post here.

Steve is a talented and meticulous modeler. He goes into great detail on the construction of his rendition of the Blackburn. I am certain his version will turn out to be a top competitor.

Detail of a hand drawn Clark Y airfoil

Detail of a hand drawn Clark Y airfoil

Mini Vapor and Tiger Moth


Ares Tiger Moth ready to fly RC model plane

Ares Tiger Moth ready to fly RC model plane

I recently purchased two ready to fly models, Horizon Hobby’s Mini Vapor and the Ares Tiger Moth. Both are interesting models and come from quite differing design perspectives. I look forward to the test flights when our indoor flying venue opens on Sept 16th.

My first impressions are positive. Both models are well made and very light weight. The Mini Vapor uses a lot of carbon rod technology and plastic film covering to achieve its weight goals. The Mini-Vapor uses a 30 milliamp lipo battery. This is one of the smallest batteries I have seen to date. As a general rule, you can get a good idea how serious the designer is by the size of the battery.

The Mini Vapor uses a ParkZone “brick” that combines the receiver, two linear servos and electronic speed control into one compact unit. The brick is located aft to ensure the correct center of gravity.

The Mini Vapor uses all-moving control surfaces which is a useful method for positive control with low flight speeds. There is even an airfoil shape via plastic ribs for the wing.

I made a short test hop in our indoor garage. The Mini Vapor handles well and will provide good practice on paying attention to slow flight characteristics. Learning how to handle an aircraft flying at low airspeeds is a skill sometimes not fully learned by the RC flying community.

Slow flight involves the use of pitch to control airspeed and throttle to gain or lose altitude. Becoming comfortable with slow flight, which is the flight regime for any takeoff or landing, makes you a better pilot. I’ll provide more information on the Mini-Vapor after I complete a few additional test flights.

The Tiger Moth is a great combination value with a 2.4 GHz transmitter, built in charger and a completely assembled aircraft. The Tiger Moth employs an actuator for rudder control and a liner servo for the elevator. The electric motor throttle is via an electronic speed control.

Mini Vapor RC model plane in flight

Mini Vapor in flight

A lot of thought went into the Tiger Moth ready to fly design. The aircraft is made from foam. The wings, struts, landing gear and lipo battery are all held in place with rare earth magnets. This is an innovative technique that I have not seen before.

The advantage of the magnets is their light weight while retaining the ability to allow a part of the aircraft to safely separate in the event of a bump into a wall or hard landing. Glue does not provide this option, while almost certainly adding more weight than the magnets.

The Tiger Moth’s wing incidence settings are precisely set in place via the length of the cabane struts. The foam wings have a well-defined airfoil shape.

All in all, two carefully designed ultra-light weight radio control models. More to follow!

I also added an updated video of my Electro Aviator RC model plane. The Electro Aviator is my second model aircraft design and was published in Quiet and Electric Flight International magazine.

The Electro Aviator is a good looking sport flyer and is an ideal first plans built aircraft. The construction is straightforward and you will be rewarded with an attractive model aircraft that flies well and stands out on the flight line. Purchase a set of CAD plans here.


Electro Aviator PDF Plans


I added the Electro Aviator plans in a PDF format today. The plans will be sent via e-mail so you can get started right away. The plans print out on five 8.5 inch by 11 inch sheets. The plans will need to be enlarged 343%. I also include the plans files on three CAD formats, to include TurboCAD, AutoCAD Native and Drawing eXchange formats.

Electro Aviator model plane side view showing decals

Electro Aviator side view showing decals

Until I created the PDF files, all I was able to supply were the original CAD files. The limitation of the CAD files is that the user must have a CAD program installed on their computer to view and print the plan files. The advantage of the PDF format is that anyone can print out the plans through the free Adobe PDF Reader.

The Electro Aviator is a sport radio control model airplane. The Electro Aviator uses four channels of control and is made from normal construction materials of balsa and light plywood. The Electro Aviator makes a great initial project for someone new to plans build model aircraft.

Plans can be enlarged at a variety of office supply stores such as FedEx Office. Note that the plans can be enlarged to any size desired. Many modelers make a smaller or larger version of a design. Depending on the size difference, you may have to substitute wood sizes.

A great example of changing a plan size is Werner’s enlargement of my Blackburn plan by 125%. Given the slow speeds of this type of model and resulting lower flight loads, you can use the same wood sizes as shown on the original plan.

Stay tuned as I will prepare a plan making the Electro Aviator in a smaller size suitable for indoor flight. I am looking at around a 30 inch wingspan and a weight of under three ounces. Control will be via the ParkZone ultra micro RC equipment. More to follow as I get started on the TurboCAD drawings.

Sheet one of five showing the Electro Aviator PDF plan file

Sheet one of five showing the Electro Aviator PDF plan file

Wing Incidence and Blackburn Gallery


I added a page today discussing an airplane’s wing incidence angle setting. Getting the wing incidence right is an important part of any aircraft design, whether model or full scale.

Bleriot nose detail

Bleriot wing incidence setting

Most sport radio control model aircraft do well with around 1 to 2 degrees of positive wing incidence. For a variety of reasons this setting will make for a more stable model, one that will not hunt around seeking a pitch attitude.

Many of the newer, lightweight 3D aerobatic models come with flat airfoils and a zero degree wing incidence setting. This works well for these unique flyers in that the aircraft are rarely flying “on the wing” but rather maintaining flight directly from engine thrust.

BlackburnTopView-1000Hovering flight is an excellent demonstration of this concept. When an aircraft is hovering the wing is not producing any lift. The entire aircraft is held aloft by the thrust of the motor alone.

I discuss my experience determining the proper wing incidence during the design of the Chickadee, Blackburn and Fokker Spin. I went through an interesting trial and error process during test flights. This investigation was prompted by Werner asking a question on the differing incidence settings for the Blackburn and the Spin.

As an aside, from my USAF time flying in the F-4 Phantom, the example of a hovering 3D radio control model is a case where the thrust-to-weight ratio of the aircraft is greater than one. With the light aircraft weight compared to the power of today’s model aircraft engines, it is not at all difficult to exceed a 1:1 thrust ratio.

Chickadee electric RC plane front view

Chickadee electric RC plane front view

Some military jet fighter aircraft can exceed a 1:1 thrust ratio. This is typically at a lower fuel weight, soon before a landing is required. Due to the lack of airflow over the control surfaces typically found on a turbine powered aircraft, there is no way a full scale jet fighter can hover even though it might have enough thrust.

I am unaware of any full scale piston powered propeller driven aircraft that have enough engine thrust to hover. There is one group modifying a turboprop Super Tucano acrobatic biplane that will attempt this feat. We’ll see!

I also added a new picture gallery of the Blackburn. The photos show the Blackburn under construction, details of the wing, fuselage and landing gear, the aircraft in flight and some views of Werner’s version. Werner enlarged the plans 125%. The result is a well handling model that flies in a scale-like manner. Do check out the YouTube video.