Extra 300S - Description of the System

Section 908
Smoke System
908 - 6 Page Date: 20. April 2002
Pilots Operating Handbook
EXTRA 300S
908.7 DESCRIPTION OF THE SYSTEM
On pilot's demand the smoke system produces a trail of smoke by injection of smoke oil (straight
paraffin oil) into the engine exhaust. The smoke oil is vaporised by the exhaust gas heat and is
visible as dense smoke after leaving the exhaust.
For smoke system activation the "SMOKE ARM" switch located at the pilot instrument panel
needs to be switched ON first. The smoke „ON-OFF“ toggle switch is located on top of the
throttle lever. For filling the smoke oil tank the "SMOKE REFILL" switch needs to be ON. After
the refill process is completed the "SMOKE REFILL" has to switched OFF. When both switches
("SMOKE ARM" and "SMOKE REFILL") are in the ON position, the smoke system is not
energized and will not run. There are two different systems approved:
A) DUAL PUMP SYSTEM
The smoke oil tank is filled by a refill pump through a quick connector located in the aircraft belly
fairing. A filled smoke oil tank is detected by a float switch placed in the tank which shuts the refill
pump off. An additional injection pump placed at the firewall within the engine compartment
pumps the smoke oil from the smoke oil tank through a solenoid valve and the injector nozzle
into the hot exhaust gas to generate smoke.
The system consists of:
- Floptube smoke oil tank with float switch
- Refill pump in the pilot compartment with quick connector in the belly fairing
- Injection pump in the engine compartment with a shut-off solenoid in the pilot
compartment
- "ON-OFF" switch on the throttle lever
- Two relais (make contact type) for pumps and for the solenoid control
- "SMOKE ARM" switch to arm the system and "SMOKE REFILL" switch for refilling
placed at the instrument-panel
- Circuit breaker for pumps and control placed at the instrument-panel
B) SINGLE PUMP SYSTEM
The smoke oil tank is filled by a pump (reversed polarity) through a quick connector located in
the aircraft belly fairing. This line includes a filter to prevent dirt to enter the smoke system. A
filled smoke oil tank is detected by a float switch placed in the tank which shuts the pump off.
The same pump (normal polarity) injects the smoke oil from the smoke oil tank through an
overpressure/check valve and the injector nozzle into the hot exhaust gas to generate smoke.
CIRCUIT BREAKERCIRCUIT BREAKER
CIRCUIT BREAKERCIRCUIT BREAKER
CIRCUIT BREAKER
SWITCHSWITCH
SWITCHSWITCH
SWITCH
ON ON
OFF OFF
SMOKE SMOKE
ARM REFILL
SMOKE SMOKE
PUMPS CONTROL
BREAKER
5
10 or 15
Page Date: 20. September 2006