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Type C 26 has 100 hp Bristol 'Lucifer' engine and is suitable for training and practice purposes as well as for aerobatics. The safety of all three types is exceptionally high, but nevertheless a normal curb weight is achieved by reducing the number of superfluous construction elements. As a result of the different engine weights, the A-fall safety is tenfold for type C 23, 8.5 times for type C24, and one fold for type C26. Fracture tests were carried out and no fracture was achieved in the A-case when a complete sash was loaded with clamping and connection fittings with 9-fold safety of type C24.
The cell consists of 4 equal surfaces, the vertical canopy, 2 N-stems and 2 support cables and 1 counter cable on each side. The wings are designed with two spars and
have only 7 identical ribs each. All ribs, with the exception of the end rib, are open, so that the surfaces can be checked from the inside of the rib by means of the
illuminated lamp after hard landings. The planking is made of plywood. The wing skeleton is built only from the two spars, a simple inner
tube truss to accommodate the resistors and the spar twist and the 7 ribs. The transverse stiffeners of the planking between the ribs are applied with
the planking. The wing built in this way is extremely easy to repair. The ailerons are located in the upper wing.
The hull consists of three main parts, the engine bridge, the tubular steel chassis and the wooden hull. The tubular steel motor bridge is
connected to the tubular steel chassis with 4 bolts. The engine, including the radiator and all fairings, can be removed from the fuselage by loosening 4 nuts.
The tubular steel chassis accommodates the two seats as well as all the controls internals. This consists of a horizontal longitudinal shaft, which carries the two control sticks for leader and pupil at its front and rear end.
The rudder levers are mounted separately. The elevator is operated from the rear stick by straight ropes, the front and rear sticks are coupled by a rod. The aileron is operated by cable pulls via diverter rollers, as is the rudder operation. The floors consist of removable wooden grates that rest on the lower longitudinal tubes of the chassis.
The wooden hull is coupled to the tubular steel chassis with the 4 spars by extremely strong node connections. All fuselage frames consist of the same profile strips, which form square frames. Similar to the surface production, the frames are not erected on a slipway, but are applied in their individual parts to the plywood planking and fastened together with this to the spars and then lashed at the corners.
The fuselage end is closed by a strong frame made of oval tube, which carries the horizontal and vertical stabilizers as well as the spur with its suspension. By
loosening the short end hood, these parts can be seen immediately. The horizontal stabilizer consists of a continuous damping surface and a continuous
elevator. The elevator is triple mounted. The course stabilizer is structured in the same way. The tail unit also has plywood planking and is similar in structure
to the wings.
The chassis is made of 2N-stems, a front M-frame, 2 auxiliary axles with lower shear plate and aluminium cladding. The distance between the auxiliary axles
is very large, so that the wheel axle can also swing forwards and backwards. The rubber ropes lie very flat in their normal state and only turn vertically when
the spring is stronger, so that a differential suspension is created, which responds very softly, but is also able to absorb heavy shocks. This
arrangement together with the large auxiliary axis distance enables take-off and landing in the worst ground or
short take-off without the aircraft jumping. The wheels in the size of 700X100 are also oversized for easy execution of outlandings.
Special emphasis was placed on fire safety with regard to rollovers, as can occur in school operations. The fuel for 2% hours of flight is
stored exclusively in a drop container in the canopy, which is covered with rubber. The precipitated fuel line is laid openly and can be closed by an easily
accessible stopcock. The carburettors are installed in a fireproof steel chamber. Behind the engine there is a fire bulkhead, consisting of 2
sheet steel walls at a distance of 30 mm with air space in between. The entire front part of the fuselage up to the driver's seat is made only of steel and aluminum. Just as much emphasis is placed on safety against injury in the event of crash landings. Both occupants are completely safe from wood splinters because they sit in the heavily oversized
tubular steel chassis, which is not dented even in the event of a severe breakage. The driver's and student compartments are heavily padded by foam rubber. Any possibility of
getting stuck on protruding parts is eliminated. The front edge of the student and driver's cab cut-out as well as the windscreens is heavily rubber-armoured. In front of the
chests of both occupants, a flexible rubber belt is stretched across the torso.
Particular emphasis was placed on easy upgrading and dismantling as well as good interchangeability of all parts. In this way, the
damaged part of the three-part fuselage can be removed and the rest of the fuselage can continue to be used. In the case of a headstand with a break in the screw and the front part of the fuselage, for example, the aircraft can be airworthy again within v2 hours by
loosening the entire engine bridge. In the event of slipping on the wing, the middle of the
fuselage will often be damaged by tearing out the connecting fittings; it can also be replaced by a new one shortly by uncoupling the engine bridge and the wooden fuselage. In case of slipping backwards, the tail unit can be replaced with the wooden fuselage, etc. In order to be able to
easily check the condition of the aircraft in all parts after hard landings, every fitting or vital point was made accessible without forcible removal of planking and panelling. For example, the motor bridge can be completely exposed immediately by opening the large side door. The chassis can be viewed at every point from the driver's and student's seats. The tail attachment is to be checked by removing the end canopy, the inside of the tail surfaces is to be checked by retractionfrom the inner ribs just like with the wings, etc