April 2011 Pg-1
These plans are for the PB-1 only, please ignore other references.
Goals of the PoorBoy designs are straight forward construction, and low cost.
Handling qualities of the Poorboy are intermediate Ultralight Aircraft.
Entry level handling Ultralight planes will fly hands off easily when trimmed
properly and are very stable usually with long wings and generous dihedral.
Intermediate handling Ultralight planes (like the Poorboy) usually have shorter
wings with less dihedral and require more attention to the controls. Advanced
handling Ultralight planes require constant control input to keep the plane
responding to the pilots wishes and will respond quickly to the controls as
acrobatic maneuvers would require (short wings and center of gravity centered
about the mid point of the airplanes mass).
The PB-1 is designed around the rotax 503 DC/DI, standard model, a second PB-1
is flying well using a 35hp cuyuna, use 35 to 50 hp air cooled engines).
The PB-H is a heavier version of the PB-1 designed for heavy pilots still using
a 503 Dual carb.
Wingspan 25’~27’ (depends on wing tip)
Wing Area 125 sq/ft. -- Wing Cord 5’
Length 20’, Width 25’, Height 6’ -- Never exceed speed 75 mph.
Build time 450 hrs. -- Engine Rotax 503 air cooled.
Aluminum tube is the primary building material in the PoorBoy and the reason
for that choice is based on quick building times, ease of repair
techniques, and the ability to see problems during safety inspections as
compared to Wood or composites. The Poorboy use 4130 steel parts in
critical areas and the covering is heat shrink Dacron fabric.
Tools required are what most folks have in their homes, you will also need
additional tools such as cable swage tool, pipe bender, and pop rivet
gun. Steel parts can be supplied by us when requested, you can build the steel
parts yourself from the plans if you have the welder also a small hydraulic press.
Materials list include 6061 T-6 aluminum, 4130 steel for some parts, fabric
covering w/supplies, and the engine. A few general hardware items like
wheels/tires are used. Aircraft grade hardware is required for all bolts,
turnbuckles, etc. Cost to build should run about $ 3000. for materials to
build the airframe. Covering cloth and cement cost about $300.00 to $500.00.
Latex paint option can save on painting costs (about $200).
April 2011 Pg-2
Materials are available from suppliers like Wicks (1 800 221-9425) and
Aircraft Spruce & Specialty (1 800 824-1930).
We use a Rotax 503 engine on the PB-1, others like Kawasaki, Hirth, Cuyuna (2SI)
can work well, power differences are obviously going to effect flight performance.
I have a PB-1 flying with a Cuyuna UL202 35hp that does fine so the 503 is not
the only engine possibility.
Building has some benefits, you can buy some parts and build as your budget allows
and you get the enjoyment and education of the project. Building also means you
know what you have internally and you have a new plane.
This is our not responsible for your butt statement. (liability release).
Safety is the big concern. Flying Ultralight aircraft can be a risky activity,
a person needs to be acutely aware of the dangers to life and limb. PoorBoy
Aviation takes no responsibility for your safety in this endeavor, these plans
are available with that understanding. These plans will show you how to build
Poorboy aircraft based on the flying prototype that PoorBoy Aviation flies.
If you do not have experience to evaluate building and flying an Ultralight
you should take the information and plans to someone with sufficient knowledge
that you trust to help you with an evaluation of this activity.
* If you are new to Ultralight aircraft:
Risk Management: The first year of driving a car or motorcycle is
statistically the most dangerous, this would also be true of Ultralights.
Riding a motorcycle might be considered twice as risky as driving a
car, flying an Ultralight is risky similar to riding a motorcycle.
There is a learning curve associated with each of these activities. Flying
Ultralights is not difficult “however” the knowledge associated with it is
* TRAINING What to expect: You should expect about 5 to 7 hrs of instruction
time in a general aviation trainer or ultralight trainer close to the point of
“solo”. What your intension would be is to learn the basic reactions and skills
of flying, this is the minimum hours of training a person needs and is not a license
requirement like the Sport Pilot License but is what is needed to be able to fly
an Ultralight with some margin of safety. You will need to know the rules of the
airways etc. "pilot training". People vary in training needs, the shortest and
quickest people to be trained are not necessarily the safest pilot.
* Special Note: As an Ultralight Pilot you have the additional duties of
engine and airframe mechanic, this is not like flying a certified aircraft where
someone else checks to make sure the aircraft is safe to fly. As an Ultralight
Pilot you are the ultimate authority and must decide if the design and condition
of the aircraft are adequate for safe flight. You can gain further maintenance
information by contacting ultralight flight instructors, airframe mechanics and
other ultra-lighters that you have confidence in, an excellent source is EAA
ultralight chapters, EAA national and ASC (Aero Sports Connection). Try your
local FBO also. If you are going the Sport Pilot route and N number the aircraft
these issues are covered in that training.
April 2011 Pg-3
“The MOPED of aviation”
An Ultralight aircraft: -- is defined as a single occupant, 254 lb. aircraft,
carrying 5 gal. of fuel, stall speed not to exceed 24 knots (28mph), not to
exceed cruise speed of 55 knots (63mph). A Ultralight can weight as much as 278
lbs. with a ballistic chute (24 lbs. weight allowance). Aircraft meeting these
parameters do not require a pilots license. The Spirit of Part 103 rule allows
for single occupant flight of an aircraft without a license with low speeds and
light weight = low kinetic energy. This formula lowers the danger to the pilot,
property, and the public; as an aircraft adds weight & speed the kinetic energy
goes up, greater fuel capacity increases fire danger and so forth. Fat Ultralights
have come about mostly from a desire to increase airframe strength, then followed
a desire for heavier engines (safer performance), greater fuel capacity (it isn’t
a good idea to run out of gas) and so forth. You don’t want to get too far from the
“spirit” of the law, the FAA has been somewhat tolerant of Fat Ultralights but as
the definition is stretched their tolerance may decrease. The alternative to flying
as an Ultralight is to get a Sport Pilots license and “N” number the plane.
Ultralights often require state registration, also knowledge by the pilot of aircraft
rules and regulations, and of course the knowledge and skill of pilot in command.
The exception should not be made to fly a two place Ultralight without registration,
proper training and (license), the FAA will not be tolerant of this, nor in good
judgment should you.
The PoorBoy has good handling and performance; it has a nice design look and the
fit and finish is up to you. The Poorboy is designed for those people who want to
do the building themselves and do it inexpensively.
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