AutoGyro MTOsport, Maintenance Manual

Page: 55 / 191

Manufacturer
Maintenance Manual
AutoGyro
MTOsport
MMM-MT-C_14-11-19 Part C
– System Description Section (Ch. 21 – 90)
Page 17 of 22
62-31-00 Rotor Head Bridge, Bearing and Teeter Tower
The rotor head bridge is made of welded stainless steel. Rotor bearing (Manufacturer Life Limited!)
and teeter tower represent one integrated component. The rotor bearing temperature (RBT) sensor is
also allocated to the rotor head bridge, respectively the rotor bearing.
62-32-00 Rotor Gimbal Head
Tilting action or flight control of the rotor is facilitated by the rotor gimbal head. The gimbal head is
sometimes also referred to as
‘hang point’ and represents a cardan hinge.
62-41-00 Rotor RPM Monitoring
Rotor RPM monitoring is realized by an inductive pick-up which is installed with a gap of 3-4 mm at the
sprocket wheel. The sensor counts the (10) holes in the sprocket disc. Rotor RPM is indicated in the
cockpit in an analogue-type instrument which also houses the control electronic. The system requires
power supply.
CHAPTER 63 - ROTOR DRIVE
63-11-00 Pre-rotator
The pre-rotator is used to quickly bring the rotor
up to safe RPM for take-off run by the press of a
button. Pre-rotation is activated by a push-button
on the flight control stick. Because of a safety
circuit, activation of the pre-rotator is only
possible with the pneumatic mode selector in
FLIGHT position and the control stick fully
forward. This prevents inadvertent activation of
the pre-rotator during flight or in BRAKE mode.
The pre-rotator is activated as long as the
respective push-button on the control stick head
is depressed, provided the following pre-
conditions are met:

pneumatic mode selector set to FLIGHT

control stick in full forward position

trim pressure less than 3 bar
In this case, the pneumatic actuator at the pre-
rotator belt clutch is pressurized, lifting the
smaller pulley out of its brake position and
tensioning the belt at the same time. Engine
torque is then transmitted through the lower pre-
rotator drive, a 90° gearbox and upper drive to
the pinion which is engaged by another small
pneumatic actuator into the geared ring of the
rotor head. The drive pinion is sliding on a
helical gear to provide automatic lock-out in
case of rotor RPM overrun. In order to allow
necessary changes in length both pre-rotator
drive shafts feature a sliding sleeve coupling.
The pre-rotator can be activated in BRAKE position to park the rotor blades fore-aft for taxi. To do so,
the pre-rotator push-button and the overdrive/override switch in the cockpit panel have to be pressed
simultaneously. Prolonged activation of the pre-rotator with rotor brake engaged should be avoided.
63-11-10 Pre-rotator Lower Engagement
Pre-Rotator (Rotor Drive)
1
– Lower engagement (belt and pulley clutch)
2
– Lower drive shaft
3
– 90° gearbox
4
– Upper drive shaft
5
– Upper engagement (drive pinion w/ bearing)