FLIGHT MANUAL
DYNALI HELICOPTER COMPANY
Edition N°3
DYNALI H2S January 2012
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7.6.
TRANSMISSIONS
- A small driving pulley is bolted directly onto the shaft emerging from the clutch shaft. Eight
trapezoid belts transmit the movement of the main pulley to the upper pulley which contains
the two free wheels. The shaft transmits the movement towards the front of the main rotor
via the main transmission box and towards the tail rotor via a flexible joint then to the rear
transmission box.
- The long transmission shaft for the rear rotor is supported by bearings in the tail tube.
- The main transmission box includes conic gearing with helicoidal cogs providing a single
reduction stage, lubricated by an oil bath. It is cooled by the circulation of the oil and by an
air vent.
- The rear transmission box also contains a pair of conic gears with helicoid gears lubricated
by an oil bath. The inward and outward shafts are made of stainless steel.
« HIGH » OIL LEVELS IN THE MAIN TRANSMISSION AND OF THE TAIL ROTOR
GEARING ARE EXTREMELY IMPORTANT ; MAINTENANCE OF THIS HIGH LEVEL IS
DESIGNED TO AVOID CAVITATION.
7.7.
ENGINE
Subaru DS EJ25 engine
Stroke : 2500 cm
3
Power : 180HP
Motor structure : Subaru
Electronic injection : MOTEC
Exhaust : Dynali
7.8.
FLIGHT CONTROLS
Standard equipment includes dual controls. The cyclic on the passenger side can be
removed. All controls are activated via shafts with maintenance free ball joint ends. The
flight controls of the Dynali H2S operate in the same way as the controls of most other
helicopters. The cyclic and the collective control the pitch of each blade via a cyclic teetering
hinge.
The cyclic stick is double but the two elements can be separated. The regulations only allow
dual control during pilot training with an instructor.
The collective is also of the classical type with a twisting throttle grip. An electronic system
controls the fuel supply as a function of the collective but fine adjustment is still necessary
and is supplied by a servo called the governor. The governor acts on the air intake valve of
the injection system. It is commanded by the computer.
The friction of the collective is adjusted by the torque tightening of its attaching bolt.
It is possible to take off with a failed governor but the pilot must then adjust the throttle grip to
maintain 100% on the rev. counter until landing)