Section 4 – Normal procedures
INTRODUCTION
1. INTRODUCTION
Section 4 describes checklists and recommended procedures for the conduct of
normal operations for P2006T aircraft.
1.1. NORMAL OPS GENERAL RECOMMENDATIONS
The following points should be always brought to attention to pilot/instructor/operator when
operating a Tecnam aircraft equipped with variable pitch propeller:
1. Propeller governor ground check.
As prescribed by the propeller/governor manufacturer, a drop of 400/500 propeller RPM
should be produced during this check. Its aim is to confirm the governor efficiency, not its
complete feathering function.
Especially during the first cycle of propeller lever pulling, the governor tendency is to respond
to the input with consistent delay, causing the pilot to continue moving back the propeller lev-
er until an abrupt RPM change is observed. This causes an excessive drop in propeller speed
that may reach up to 800 RPM in some cases and, consequently, a drop of up to 2000 engine
shaft RPM. The long term result is a major wear of engine gearbox, bushings and pistons. In
some cases, it may also result in detonation.
In order to avoid these long term adverse effects, the governor ground check should be per-
formed by slowly and gently pulling the propeller lever. The purging cycle should be repeated
3 times, making sure that the governor closely and firmly controls the rpm.
The following recommendations have to be followed during the test:
- propeller speed drops shall be of 400/500 propeller RPM
- the cycle shall be repeated 3 times
- the pilot shall be ready to push the propeller lever if a drop of >500 RPM is recorded
2. Power changes.
When power setting changes are required in any flight condition, remember the following cor-
rect procedure:
Power increase = FIRST Prop THEN Map
Power reduction = FIRST Map THEN Prop
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