Cavalier

The SA102.5 Cavalier is a much modified and refined development of the GY-20 Minicab. It is in the same French tradition, as the Jodels, the Emeraudes, and other fine wooden aircraft from Europe, but designed in Western Canada by Stan McLeod. The first flight of the prototype SA 102 was made in 1964 and subsequent development (such as the addition of tip tanks) lead to the first flight of the SA 102.5 in February 1971.

Basically, a SA102.5 Cavalier is a two-seat (side by side) cantilever low-wing monoplane. The wing section is a NACA 23015 at the root and NACA 23012 at the tip. The wing structure consists of a single wooden box spar, plywood leading edge, and an auxiliary rear spar to carry the flaps and ailerons. The centre section and leading edge of the wing is plywood covered, the remainder covered with fabric. The fuselage is a wooden truss type structure of spruce and birch ply construction. The cockpit doors and canopy are of fibreglass. The rear decking is fabric covered as are the control surfaces. The standard aircraft has a fixed tricycle under-carriage with spring steel gear legs. Fuel is carried in wing tip tanks of up to 22 Imperial gallons capacity. Engine options range from 85 hp to 135 hp.

Some Notes from the Designer - Mr Stan McLeod (April 2004)

SA102, SA102.5, SA 103, SA104 Cavaliers and SA105 Super Cavalier

The Cavalier started life as the SA102 Cavalier and the prototype; built by Forest Fenton of Calgary, flew with 135 hp Lyc in 1963. This was a fairly basic machine by present day standards but was the aircraft that proved the "Rod Nose Gear" could be made to work (others had tried and failed). The original prototype just plain wore out, was rebuilt and I believe still exists. Could use engines from 85 to 135hp, could be built as tri gear or tail dragger and was easily convertible from one to the other.
NOTE: the tail dragger turned out to be around 15 mph SLOWER than the tri gear and didn't handle rough fields any better than the tri gear; however both offered excellent handling on the ground. Some builders demanded retractable gear for the Cavalier and this was not practical so I spent some 4-5000 hrs designing a new airplane with retractable gear - the SA105 Super Cavalier.

SA105 Super Cavalier (1968)

This airplane follows the same basic construction pattern as the SA102.5 but is beefed up to;
1) take larger engines and variable pitch props from 125 to 200 hp, including auto conversions
2) withstand the higher gross weights necessary
3) withstand the higher stresses of the higher cruising speeds
4) enlarged cockpit
    a) to house two people comfortably for long cross country flying
    b) more radios and instruments for x country and IFR flying
    c) provide room for the retracted nose wheel and pilots/pass, legs
    d) added baggage space necessary for x country travel
5) fuselage is 4" wider and 4" taller than the 102.5 and 7" longer
6) wing structure is beefed and modified to accept retractable gear and mechanism
7) tricycle landing gear is all spring steel and manually retracted similar to the early Mooneys. hydraulic retraction can be adapted quite easily
8) streamlined fibreglass tip tanks are added to remove all fuel from the cockpit and increase the aspect ratio and wing area (these tanks produce lift and reduce drag).

specifications
 
powerplant
propeller
length
height
wing span
wing area
seats
empty weight
useful load
gross weight
fuel capacity
range
Lycoming O-290GPU 135hp
metal 69x69
x
x
x
x
2
975 pounds
x

1500 pounds
x
x

performance

takeoff distance, ground roll
rate of climb
max speed
cruise speed
landing distance, ground roll
service ceiling
x
1000 fpm
185 mph
160 mph
x
x

limiting and recommended speeds

design manoeuvring speed (Va)
never exceed speed (Vne)
stall, power off (Vsl)
landing approach speed
x
x
55 mph
x

All specifications are based on manufacturer's calculations