A21 S : the Pleasure of Flying
By the A-21S a pupil learns more quickly and profitably under the direct control of the instructur sitting by his side and thanks to the great Calif' s teaching effectiveness. The A-21S being certified for normal aerobatics and cloud flight can operate in all conditions. No one can expect a more "honest" and harmonious behaviour from a sailplane of this type : quick response to controls, high stability and manoeuvrability , straight and progressive stall in all conditions, reluctancy to entering spin and spontaneous and prompt exit.
Calif A21-S is RAI , FAA , LBA and DGAC certified. Proof of Calif' s excellent qualities are several national and international records set up this gliders and the fact that they are being used in many civil and military soaring schools with great satisfaction and outstanding results.
A21 SJ : Soaring in Freedom
As a metter of fact only the "cleanest" jetglider on the world could have stemmed from a glider like the A-21. The A-21SJ, far from being a cross-bred, is on the contrary the only motorglider having an engine really integrated in the structure , without any decay in the aerodynamical efficiency when the plane is used as a pure sailplane. Careful studiesand a consistent extension of the "Calif philosophy" have led to an easily accesible and exemplary powerplant installation, efficient and unsophisticated at the same time, and to an almost total elimination of parasite drag. Up to 90 percent of parts are common to both the A-21S and the A-21SJ, so that the glider can be easily transformed into a jetglider even in retrofit. The main differences - besides of course the powerplant installation and the related equipments - are in the lading gear (enlarged legs and wheels, tailwheel enlarged, swiveling and connected to pedals) in the instrumetation and in some aerodynamic fairings. The A-21SJ can install turbine engines having a thrust ranging between 90 and 130 N and the engine may be started and stopped at will in flight under any condition. As a motorglider the A-21SJ makes use of powerplant just for autonomous take-off, to climb and regain height in case no rising airstream should be present.
In addition to that, the A-21SJ behaves exactly like an aeroplane, when the turbojet is kept working during the whole flight. While keeping the qualities of sailplanes such as the high efficiency and the low stall and landing speeds, it features the same level of comfort, mobility, speed and range as an aircraft. Peculiar advantages are lastly a very low fuel consumption, an exceptional ceiling (over 33,000 ft) and a negligible noise level.
The engine is easily accessible trough a handy opening panel. All normal maintenance operations can be done quickly and easily. Fuel is contained in wing and fusolage tanks with a total capacity of 138 literes. Consistently with the above said "Calif philosophy" the engine air intake can be closed in flight to restore the perfect aerodynamics of the sailplane. The high positioned air intake prevents foreing objects from being ingested. The position and orientation of the engine exhausts are such as to cause no problem of ground erosion or grass field demaging.