16.1 General
The operational safety of the craft in normal service conditions and in equipment
failure situations should be demonstrated by full-scale tests of the craft itself or an
identical craft. The objective of tests is to determine information to be included in
the craft operating manual in relation to:
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.1 handling and performance limitations;
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.2 actions to be taken in the event of any foreseeable failure of equipment,
systems or structure; and
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.3 limitations to be observed for safe operation following the failures listed in
.2.
16.2 Proof of Compliance
Information on controllability and performance should be contained in the operating
manual. It should include the craft performance characteristics exhibited during the
manoeuvres prescribed in 16.5.3, 16.6 and 16.7. The parameters of the worst intended
conditions in all operating modes should be included. Compliance with the performance
characteristics listed should be demonstrated in accordance with part C and through
trials carried out in accordance with annex 8.
16.3 Weight and Centre of Gravity
Compliance with each of the handling, controllability and performance provisions should
be established for all combinations of weight and centre of gravity position significant
for the operational safety in the range of weights up to the maximum permissible weight.
16.4 Effect of Failures
The effect of any likely failure in control devices, services or components (e.g. power
operation, power assistance, attitude and altitude control systems) should be assessed
in order that a safe level of craft operation can be maintained. Effects of failure
identified as being critical according to part C should as far as practicable be
verified through the trials conducted in accordance with annex 8.
16.5 Controllability and Manoeuvrability
16.5.1 The effort required to operate the controls in the worst intended conditions
should not be such that the person at the control will be unduly fatigued or distracted
by the effort necessary to maintain the safe operation of the craft.
16.5.2 The craft should be controllable and be capable of performing those manoeuvres
essential to its safe operation up to the critical design conditions.
16.5.3 When determining the safety of a craft in respect of controllability and
performance, the Administration should pay particular attention to the following aspects
during normal operation and during and subsequent to failures:
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.1 yawing;
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.2 turning;
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.3 stopping in normal and emergency conditions;
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.4 for all operational modes other than the displacement mode, stability about
three axes and in heave;
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.5 trim and flight trim;
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.6 plough in; and
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.7 lift power limitations.
16.5.4 The terms in 16.5.3 are defined as follows:
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.1 Turning is the change of direction of a craft's track at its normal
maximum operating speed in specified wind and sea conditions.
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.2 Yaw is change of direction of a craft's heading without a change in the
craft's track.
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.3 Trim, when applied to the displacement or other modes up to and
including planing, means the difference between forward and aft draughts.
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.4 Flight trim means the condition of the craft whereby control surface
settings are such that the craft attitude and direction is maintained without
significant operator input.
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.5 Plough in is an involuntary motion involving sustained increase in drag
of a craft at speed, usually associated with partial collapse of an air cushion.
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.6 Lift power limitations are those limitations imposed upon machinery and
components which provide lift in operational modes other than the displacement
mode.
16.6 Change of Operating Surface and Mode
There should be no unsafe change in the stability, or controllability, altitude or
attitude of the craft during transition from one type of operating surface or mode to
another. Information on the behaviour characteristics of the craft during the transition
should be included in the craft operating manual.
16.7 Surface Irregularities
Factors which limit the ability of the craft to operate over irregular, sloping or
discontinuous sea or land surfaces should be determined, as applicable, and included in
the craft operating manual.
16.8 Acceleration and Deceleration
The Administration should be satisfied that the worst likely acceleration or
deceleration of the craft would not hazard the persons on the craft, following any
foreseeable failure, emergency stopping procedures or other likely causes.
16.9 Speeds
Safe maximum speeds should be determined, taking account of modes of operation, wind
force and direction and the effects of possible failures of any one lift or propulsion
system over calm water, rough water and over other surfaces, as appropriate to the
craft.
16.10 Minimum Depth of Water
The minimum depth of water and other appropriate information required for operations in
all modes should be determined.
16.11 Hard Structure Clearance
For amphibious craft, when cushion-borne, clearance of the lowest point of the hard
structure above a hard flat surface should be determined.
16.12 Night Operation
The schedule of tests should include sufficient operation to evaluate the adequacy of
internal and external lighting and visibility under conditions of normal and emergency
electrical power supply in all operational modes and during docking manoeuvres.