CGS Avaition, Inc
PO Box 470635 Dept 2nd
Broadview Hts, Ohio 44147
Phone: 440-632-1424 x 110
Fax: 440-632-1207
http://www.cgsaviation.com/
Check out photos from the 1996 & 2001 Labor Day flyin and
the hawk I personaly have for sale and a movie taken inside it while flying.
The HAWK was designed in the era of foot launching, weight shift
controls, and throttles held in the mouth. It was meant to raise the
level of powered hang gliders as they were called, to the level of
conventional, full-sized aircraft. Ultralights back then couldn't fly
in winds much above 5 mph or in crosswinds of any velocity. The pilot
was uncomfortable in cold weather and had to really think about what he
was doing before taking off. Basically, an ultralight was a very
restricted toy. The HAWK revolutionized the entire ultralight industry
by raising the level of performance, design, pilot protection and
comfort to the same standards as full sized aircraft. Noted aviation
writer Peter Lert said the HAWK was the "first proper little airplane".
The design criteria of the HAWK was as follows: pilot protection,
crosswind capability, ability to fly in high wind, responsive controls,
rugged design and pilot comfort.
Pilot Protection and Safety
The first concern during the HAWK's design was how to best protect the
pilot during a forced landing in trees, rough fields, barbed wire
fences, or other unforeseen obstacles. The sturdy bridge-like structure
of one inch diameter tubing forms a roll-cage which surrounds the pilot
completely. Combine this with the seat belt and shoulder harness
restraint systems and you have the ideal situation wherein th airframe
takes the initial shock of impact instead of the pilot. THIS IS AN
IMPORTANT BUFFER ZONE. Designs where the pilot is completely, or
partially hanging out of the airframe, can allow him or her (rather than
the airframe) to take the first impact, in an emergency situation. The
shape of the nose serves a dual purpose of aerodynamic efficiency and
pilot protection. In the event of a tree landing, or any landing where
you might go through some type of irregular mass, this nose shape allows
the branches, or other mass, slide above and below the pilot, much like
a wedge. All these features for pilot protection can sound gloomy, but
fortunately you will probably never need them. Like car insurance
however, it's good to have it when you do need it!
Engineering
The HAWK, unlike most early ultralight designs, was not a converted hang
glider. It was designed from the wheels up to be a proper little
airplane. The engineering phase of this design took over a year before
any metal was actually cut. The engineering criteria used was that for
conventional airplanes.
Testing
CGS AVIATION performed load tests of the control system and various
control system methods. Landing gear drop tests were performed as well.
Load testing of the wings in both positive and negative conditions, load
testing of the horizontal and vertical tail assemblies for gust and
positive and negative loadings verified the engineering data as to the
strength of the airframe. Flight tests included stalls in all
configurations (with and without flaps), maximum gross weight take offs
and landings, tuft testing, prop tests, maneuvers, spin attempts, and
high G maneuvers. We followed the normal guidelines for flight testing
a new design. The first two HAWK prototypes had over 200 hours each
before we sold the first HAWK to a customer.
Maintenance
The construction of the HAWK, utilizing anodized aluminum tubing and
gussets held together with pop rivets, allows for easy repair even in
the field if necessary. For example, a bent tube can be removed by
drilling out the rivets with a battery powered drill and installing the
new tube using rivets and a hand operated pop riveting tool. The HAWK
features completely anodized tubing which stops corrosion and allows for
long life airframes. Many HAWKS built in 1983 are still flying today!
Performance and Features
The HAWK's wide landing gear serves two functions. First, it allows for
greater crosswind capabilities (20 knots, 90 degrees, tested). The
wider gear also lets stones or gravel (which can be kicked up by the
tires and thrown backwards) not hit the propeller. In narrow landing
gear designs, the prop disk is directly behind the tires, throwing
stones into the prop. The large horizontal stabilizer area provides
exceptional longitudinal stability and a broad CG range. The large
vertical stabilizer and rudder also provide exceptional yaw stability.
The HAWK maintains positive elevator control right through a stall. The
curved boom tube serves many useful purposes. It allows the horizontal
stabilizer to be mounted above the downwash of the wing and flaps,
allowing you to slip the HAWK with the flaps down. It provides for the
gear legs to be shorter while still having enough clearance at the tail.
Shorter gear legs also allow the vertical CG to be lower for enhanced
ground stability and easy entrance and exit to the cockpit. And, it
looks good too! The process of bending the boom tube work hardens it a
bit, increasing its tensile strength. A curved tube is also torsionally
stiffer than a straight tube. The kit itself comes with the wings,
horizontal and vertical stabilizers, elevators and flaps onstructed, the
welded parts complete and 51% for you, the builder, to pop rivet and
assemble. The covering fits onto the wings and fuselage like a sock
onto a foot.
Flight Characteristics and Performance
In 1982 the CGS HAWK forever changed the profile of the Ultralight
world. Designed by Ultralight pioneer Chuck Slusarczk (who patented
powered hang gliders), the HAWK was the first of the "proper little
aeroplanes." The CGS HAWK masterfully integrated conventional and
low-speed aerodynamics, to provide pilots with flight characteristics
that instill a feeling of confidence in the design. The Hawk’s unique
double-surfaced airfoil and 4-position flaps enable the pilot to get
into and out of small fields with authority. When the flaps are
retracted, the smaller wing and higher wing loading enables one to
cruise comfortably at speeds of 55-75 mph, even in rough air. The CGS
HAWK incorporates features recommended by a NACA (National Advisory
Committee for Aeronautics) report, resulting in an aircraft with a
well-behaved stall andinherently incapable of spinning. The Hawk has
standard three-axis control; joystick controlled ailerons and elevator
along with pedal operated rudder. The ailerons are large, with positive
control through all speed ranges. Differential rigging on the ailerons
eliminates adverse yaw. The Hawk is a light aircraft with the feartures
the experienced pilot deserves. Besides being easy to fly, the Hawk
provides a clean design. This combination translates into performance
unavailable in any other light aircraft.inherently incapable of
spinning. The Hawk has standard three-axis control; joystick controlled
ailerons and elevator along with pedal operated rudder. The ailerons
are large, with positive control through all speed ranges. Differential
rigging on the ailerons eliminates adverse yaw. The Hawk is a light
aircraft with the feartures the experienced pilot deserves. Besides
being easy to fly, the Hawk provides a clean design. This combination
translates into performance unavailable in any other light aircraft.
Consider these standard features:
100% double-surface wings, high-lift, low-drag airfoil.
3.8 oz precolored dacron cloth (Ceconite optional), design options
available.
Rugged, strut-braced wings. Strut-braced stabilizer with large area for
added stability.
Removable wings for easy storage and transportation.
Ailerons stick operated and very smooth.
Stick operated elevators are very responsive.
Pedal operated rudder, functional at very low speeds.
Flaps are full 4-position (0-15-30-45), for extra short field takeoffs
and landing.
Steerable nosewheel – push right, go right (steerable tailwheel on
taildragger).
All controls are stainless steel cable actuated, with hight quality
fillings used throughout.
Permanently mounted seat, seatbelt and shoulder harness.
Rollcage cockpit provides added protection.
Enclosed cockpit provides windbreak, allows year-round flying.
Durable Lexan windows provide excellent visibility all around, lasting
clarity.
Removable side windows for cool summer flying.
Large, convenient access panels on both sides, to reach fuel tank,
engine and storage areas.
Rotax powerplant for proven dependibility.
Rigid tailboom speeds construction, maximizes strength.
Stable tricycle landing gear (taildragger or floats optional).
Airspeed indicator, Altimeter and Temp Gauges.