9.3.1 The gas turbine should be free from surge
or dangerous instability throughout its operating range up to the
maximum steady speed approved for use. The Administration should take
measures to ensure that the turbine is not operated within any speed
range where excessive vibration, stalling, or surging may be encountered.
9.3.2 The strength of turbine engines should be
such that any reasonably probable shedding of compressor or turbine
blades will not lead to damage that would be likely to hazard the
craft, its occupants or any other personsfootnote.
9.3.3 Any turbine should be so installed as to
avoid excessive vibration within the craft.
9.3.4
Sub-paragraph 9.2.7 should
apply to gas turbines in respect of fuel which might reach the interior
of the jet pipe or exhaust system after a false start or after stopping.
9.3.5 Turbines should be safeguarded as far as
practicable against the possibility of damage by ingestion of contaminants
from the operating environment. Information regarding the recommended
maximum concentration of contamination should be made available to
the Administration. Provision is to be made, if necessary, for preventing
the air intake from icing.
9.3.6 In the event of a failure of a shaft or
weak link, the broken end should not hazard the occupants of the craft,
either directly or by damaging the craft or its systems. Where necessary,
guards may befitted to achieve compliance with this requirement.