WHY USEFUL AIRCRAFT?
Tools, not toys.
These were my goals in designing Useful Aircraft, and some notes on things I discovered along the way.
Fast and easy builds. Experienced builders can build airframes in about 15 minutes.
Easy to repair. Inexpensive materials can be used to get you flying again quickly. Painters tape, hot glue and hotel key cards can fix about anything.
Unobstructed FPV view. No airframe or propellers in your picture.
Generous Internal space, big enough to fit:
Raspberry Pi's and other Single Board Computers
Arduinos and other micro controllers
Go Pro cameras in a nose mount (careful with CG)
Insta360 cameras (sticking out the top)
RunCams
External loads of over 500 grams have been flown repeatedly.
Room for Autonomous Flight Controllers, GPS modules and other accessories. I've experimented with:
Matek F405
Matek F411
Pixhawk
Generic F7 boards
Various Stabilizer boards
Built in Crashworthiness
Protecting what's onboard with a nose designed to absorb loads, and a fuselage that will protect your installed equipment in all but the most serious of impacts.
Protecting what you hit by not having a motor and a propeller be the first thing to make contact with any object you run into.
Good Flight Characteristics
Stall Behavior - with or without leading edge cuffs, stall behavior is predictable, and with plenty of warning. Stall break is most commonly straight ahead, and the vertical stabilizers arrest any tendencies towards spins.
Control responsiveness is good. Roll rates are obviously coupled to airspeed, but roll control is crisp in cruise.
Pitch control is enhanced via induced flow. Regardless of speed, pitch response is possible if coupled with power. Elevator response is precise.
Wide Center of Gravity envelope. It's possible to fly the aircraft with an amazing variety of stores and battery combinations thanks to a very authoritative pitch control. Effective use of trim and cautious widening of your flight envelope when testing new CG positions will demonstrate this ability. Obviously there are limits - but it's amazing what and where things can be carried.
Reasonable size. A ready to fly airplane (or two) fits easily in a car trunk.
Good Cooling. The Packet was designed from the start for operations in Arizona summertime heat. Good airflow through the fuselage will help to keep your internals cool.
Good Radio Frequency passthrough. Antennas can be mounted internally. I routinely fly with internal GPS antennas, Wifi, Bluetooth, and antennas for radio control and telemetry mounted inside my planes.
Inexpensive enough to try new things. You break things while innovating, and this aircraft let's you get back in the air quick.
Easy to transport. If needed in a remote location, Packet's can be shipped and built quickly on site. When work is completed, only the electronics are returned.