Flying wings have been around since man first attempted to fly. Defined as an aircraft with no tail or defined fuselage, a flying wing usually has no protruding structures except for motors/engines, antenna masts, or other minor changes to the general wing shape.
Pros of Flying Wings as FPV Aircraft
Several benefits are unique to flying wings. First, they are less prone to wind disturbances and more stable when flown on windy or gusty days. The lack of a large cross sectional area, such as a fuselage or a tail boom, allows the wing to cut through the air with less buffeting and turbulence.
Not a flying wing – Skywalker before flight.
Second, a flying wing can typically achieve higher speeds than a similarly sized RC airplane. This is due to the wing’s more aerodynamic design. A conventional airplane has more drag caused by the fuselage and secondary control surfaces found on the tail.
Third, for a given weight flying wings provide greater lift capability. The entire aircraft body provides lift, compared to the fuselage on a plane that adds weight but no lift.
Cons of Flying Wings as FPV Aircraft
The placement of FPV components on a wing is much trickier than on a conventional RC airplane. Without the benefit of a large fuselage in which to house the FPV components, one must install the video transmitter, autopilot, stabilization system, batteries, and other gear directly inside the wing itself.
The insertion of the electronics directly into the wing can be done by either using a razor blade and cutting into the foam, or melting the foam with a hot soldering iron. It’s important not to weaken the wing too much by cutting or melting too deeply or at structurally important areas, such as where the foam is thin or near control surfaces.
This cutting or melting of locations can reduce the structural integrity of the entire wing and may cause instability in flight, or a greater degree of damage in a crash. EPP foam is arguably the best material from which to construct your wing. Crash Test Hobby specializes in providing EPP foam flying wing kits and helpful build videos. Their service and quality are top notch. They also have excellent advice on what motors, servos, and speed controllers to use in their products.
Most beginner FPV pilots will want to start with simple trainer-type FPV plane designs for their first few FPV experiences. However, once a pilot becomes proficient flying airplanes by FPV, it might be fun to try FPV with a flying wing design.
Which Flying Wing to Buy?
Several flying wing models are available commercially, and these have been tested and reviewed many times. The flying wing section on FPVLab has many reviews and discussions regarding adapting the flying wing platform to FPV use.
Alternatively, flying wings can be constructed from scratch using some simple and inexpensive construction methods and materials. rctestflight has developed several of his own designs using insulation foam and poster board.
These cheap and easily found materials make designing your own flying wing a fairly easy process. Still, for optimal performance, flight time, and FPV satisfaction, it’s probably better to purchase a kit or RTF flying wing before attempting to build your own from scratch.
Preflight Checks on an FPV Flying Wing
There are a couple of unique considerations that one must think about before flying a wing, either RTF or home built. The first is that the correct center of gravity, although important on regular RC airplanes, is critical to a flying wing’s stability. This sensitivity to center of gravity means that one must check, and recheck, where the plane balances before flight.
Flying Wing Reflex 1/4″ on 78″ wing.
In addition, if a flying wing is used as an FPV setup, setting up the correct center of gravity becomes even more difficult.
In a normal RC FPV airplane one can just shift components, especially the heavy batteries, around in the fuselage to arrive at the desired balance point. With an FPV wing, however, the battery compartments and other equipment positions must be cut or melted into the foam itself.
A second consideration is that of setting the correct reflex before flight. Reflex provides an aircraft without a fuselage or elevator with aerodynamic pitch stability. More on this phenomenon can be found on the reflex wing Wikipedia entry. This effective uptrim on the elevons depends on the wing size, but is usually around 1/4″. Not setting the reflex correctly can make the wing unflyable.
It’s also important to have strong servos running the elevon control. Since elevons are a wing’s only useful control surface, they need to be stable to prevent the wing from fluttering at high speed.
Crash Test Hobby provides an excellent flying wing pre-flight checklist on their site.