Small-Field Flying
Paul Bradley | [email protected]
THE BUILDING SEASON is upon us. Based on the cover date of this issue, we are nearing the end of the calendar year and are into the traditional building season.
Also included in this column:
- New Pat Tritle kits from Manzano Laser Works
- Sky Greenawalt’s Acme Aircraft Company offers new kits
These days the building season can mean different things to different modelers. For some it represents an opportunity to launch a nice build-it-yourself model. Others will use the time to assemble the already-built components of a highly prefabricated model. Either way, the time represented by the winter months is a great period for adding one or more new models to our small-field-flying hangar.
With so many good prefabricated or ARF kits available, it is only natural that the modeling press tends to give that type of product more print space. Quality offerings combined with the demands of life taking away from precious building time have led to a strong following of ARF models. I know that I have gone that route on more than one occasion in recent years.
Although the ARF choices of today are getting a lot of attention, I’ve seen some excellent kits for those of us who also like to build a model from the ground up (pun intended). Converting a group of parts or blank sheets of our chosen building material into a nice-looking and -flying small-field model is satisfying.
The main issue is having the time to devote to such projects. It might be argued by those who are fairly new to the hobby that know-how is also a consideration when starting a build-it-yourself project. Fortunately, technology available to the kit developer today has done wonders for making those two factors less of an issue.
Laser-cut parts have moved the build-it-yourself model to a totally new plateau. The parts are quite accurate and can take advantage of advanced design approaches which allow the components to be quickly assembled into properly aligned, strong, light structures. This makes the process of assembling the basic structures of a model go quickly.
The underlying design of the model structure also makes it possible for people with little or no building experience to achieve great results from the start, especially when supported by the comprehensive building manuals that many of today’s build-it-yourself kits include.
With this in mind I want to discuss several excellent build-it-yourself kits that are fairly new on the market.
I have had the great pleasure of showcasing a number of the models designed by Pat Tritle. His many different aircraft are being produced as short kits through Manzano Laser Works. The kits contain the full-size plans, all laser-cut parts, and plastic parts if applicable. The builder supplies strip wood, piano wire, wheels, covering, and other hardware.
I want to discuss two models that represent a new trend: a larger-size model that works well in the small-field venue. The secret is keeping the airplane lightweight while increasing the overall size. The bigger sizes are nice from a flying-quality point of view and for being able to view the model in flight.
Shown is a 44-inch Tiger Moth. Pat has a smaller version but is now offering one in a larger size. What makes it so special is its flying weight: a scant 19 ounces or less, depending on the battery and motor choice.
The 44-inch wingspan translates into 570 square inches of wing area. Talk about a floater! The wing loading is only 4.8 ounces per square foot.
The model in the photo is using an E-flite 920-rpm-per-volt Park 400 outrunner motor powering an APC 11 x 5.5E propeller. Its energy comes from a 2100 mAh two-cell Li-Poly battery pack. It features aileron, rudder, elevator, and throttle control functions.
This leads me to a discussion about structural design for our models. Pat Tritle’s aircraft are designed for electric power. We normally associate electric power with quiet operation. That is certainly true, but another important factor for electric power is no vibration. This is huge when it comes to designing a lightweight model. You don’t need nearly as much structure to keep things together in flight.
To help illustrate this point I have included a picture of my version of Pat’s 44-inch Tiger Moth under construction. (I fell in love with the model and bought one of the kits.) It is similar to a large rubber-powered free-flight airplane. The structure may look frail to someone who has only built and flown internal-combustion power, but it is quite strong. It does not carry around unnecessary material, making it efficient.
By way of contrast I direct you to the October 2006 Flying Models. That issue contained a nice construction article for a .20 four-stroke, glow-powered Tiger Moth with the same 44-inch wingspan. The model is well designed and flies well on the .20 four-stroke.
Its structural design is dramatically different and yields a flying weight of 46 ounces. That is more than twice the weight of Pat’s design. Depending on your small-field venue, both models may be suitable, but the lighter one will certainly be more comfortable to fly in a small space.
Following the trend of the larger Tiger Moth, Pat has developed a 48-inch-span version of his recognizable mid-20th-century general-aviation design. I can’t mention the specific company name and aircraft model number because of design and image-licensing issues from the full-scale-airplane manufacturer. I’m sure you will recognize the model shown. This mess with aircraft manufacturers now demanding licensing fees from the modeling industry is an issue that I won’t go into here, but it sure makes me lose respect for the leadership of the full-scale-aviation industry.
The 48-inch general aviation aircraft has a wing area of 312 square inches and a flying weight of 12.7 ounces. This is another excellent, efficient, lightweight structural design that lets a larger model fly comfortably in the small-field venue.
Power for the model is a Hacker A20 turning a 10 x 3.8 APC Slow Flyer propeller on two 1320 mAh cells.
As does the Tiger Moth, this model utilizes all four flight controls. My only problem with it is its siren song saying “add me to your build list.” That list is far too long, but I fear I am likely to succumb. If you are feeling as tempted as I have been, you will find contact information at the end of the column.
I want to stay with the theme of larger, lightweight small-field models slightly longer. In addition to the kits offered by Manzano Laser Works, we are fortunate to have another innovative designer in our midst who is doing bigger-model designs that are suitable for small fields. Schuyler “Sky” Greenawalt is doing business as Acme Aircraft Company. He has several nice laser-cut kits available.
Look at the photos to see his elegant Beech D-18. At 48 inches in wingspan, it works well in a small-field environment. As does Pat Tritle, Sky renders models that have lightweight but strong, efficient structures.
The Acme Beech D-18 has a wing area of 275 square inches with a flying weight of 20 ounces or less depending on landing-gear options. Using two of the smaller brushless motors, such as the Himax 2208 or 2212, and a three-cell 1320 mAh Li-Poly battery pack, the model has excellent flying characteristics.
It is set up with ailerons, elevator, rudder, and throttle. You can even install retracts for some real scale-flying enjoyment. The 20-ounce flying weight includes retracts. (Okay, I confess that one of these kits is in my building queue as well.) Please see the contact information at the end of the column.
Just to give you an idea of what the creative designer can produce, I have included a picture of Sky with his in-progress, lightweight, 80-inch-wingspan B-24. This model is intended to be powered by four GWS IPS motor/gearboxes. That is four Lite Stik power systems flying an 80-inch-span scale World War II bomber!
The B-24 weighs a mere 11 ounces. Talk about light! Sky uses silkspan and model dope as the covering.
As a comparison, go back to the September 2006 MA and review the nice B-24 presented by Frank Baker as a construction article. Frank’s 82-inch-span model is nearly the same size as Sky’s aircraft. Frank’s is powered with four .10 glow engines and weighs 6 pounds. These models represent two successful aircraft with a different design approach based on the choice of power.
Don’t you just love the range of possibilities we enjoy in this hobby? I do hope Sky will release the B-24 as a kit when he gets it all sorted out. If he does, you can bet that my stash is likely to grow by one more.
A Summer-Flying Flashback
Before wrapping up this installment, I want to share one more laser-cut, build-it-yourself model. This is not a new offering, but one that deserves consideration.
In the pictures you will see my Herr/Sig Aqua-Star seaplane. The model is intended for glow power, but my water venue is better suited to electric.
For the photo I left the cowl off so you could see the motor installation. My choice of power is the AXI 2208-34 outrunner turning a 7 x 5 APC electric propeller and a three-cell 1320 mAh Li-Poly battery pack.
This is a lovely, lightweight model worthy of your consideration if you are looking for a good airplane to fly off water in 2007. I have enjoyed mine during the past summer flying season. The kit is available from Sig Manufacturing.
This brings us to the close of the column. With all of the new projects in progress out there, please don’t forget to send me a few pictures so we can all enjoy your efforts. I can be reached via regular mail at:
32328 Spinnaker Run Magnolia, TX 77354
or via E-mail: [email protected]
Sources
44-inch Tiger Moth and other Pat Tritle short kits: Manzano Laser Works 1 Hawks Rest Rd. Tijeras, NM 87059 (505) 286-2640 [email protected] www.manzanolasers.com
48-inch Beech D-18 and other kits: Acme Aircraft Company [email protected] www.acme-aircraft.com
Aqua-Star: Sig Manufacturing Box 520 Montezuma, IA 50171 (641) 623-5154 [email protected] www.sigmfg.com
Transcribed from original scans by AI. Minor OCR errors may remain.
