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Division 4 - Functional Tests and Trials.

Part A - Pre-operation - All A.C.V's.

4000. Before any A.C.V. may be operated for the purpose of approval or certification, the vehicle, it's machinery and systems shall be subjected to a schedule of tests to ensure the correct functioning and safety of operation of all systems and machinery. The schedule, which may include recommended procedures provided by machinery or equipment manufacturers, shall be approved.

4001. In submitting test schedules for approval, data shall be included relating to the proposed test methods, values of test parameters to be achieved, and any standards proposed.

4002. Testing shall include, but not necessarily be limited to, functioning of the following:-

1. Main propulsion machinery;
   
   
2. Main lift machinery;
   
   
3. Fuel filling, feed, transfer and vent systems;
   
   
4. Directional control systems and devices;
   
   
5. Bilge pumping systems;
   
   
6. Liquid ballast or trim systems;
   
   
7. Propulsive thrust controls;
   
   
8. Lift or cushion air controls;
   
   
9. Auxiliary power units;
   
   
10. Normal electrical power generation and distribution systems;
    
    
11. Emergency electrical power generation and distribution systems, including the operation of any switching or interlocks;
    
    
12. Emergency lighting;
    
    
13. All instrumentation and displays provided at crew duty stations;
    
    
14. All controls provided at crew duty stations;
    
    
15. All alarms;
    
    
16. All emergency controls provided;
    
    
17. Internal communication, including passenger broadcast system;
    
    
18. Compass system;
    
    
19. Ventilation and environmental control systems;
    
    
20. Radio communication equipment;
    
    
21. Any navigation equipment fitted.

4003. In addition, the following tests shall be carried out:-

1. All doors, windows and hatches shall be subjected to a water spray test, using a water jet or not less than 207 kPa, to establish that the vehicle is effectively water-tight;
   
   
2. The vehicle flexible structure shall be inspected with the vehicle on full hover, and such adjustments and measurements shall be made as may be necessary to ensure that the air cushion and it's components conform to design geometry and parameters;
   
   
3. The vehicle is to be subjected to static stability trials, in the course of which sufficient measurements are to be recorded to establish that cushion geometry and vehicle static roll and pitch stability conform to design data at weights up to the maximum for which certification is sought;
   
   
4. The vehicle is to be weighed in such a manner that it's weight and longitudinal and lateral c.g. positions may be calculated for any loading condition within the operating envelope for which certification is sought;
   
   
5. All propellers, lift fans, and their transmissions shall be subjected to tests and adjustments to ensure that they are dynamically balanced, at normal operating conditions, in accordance with recommendations of the component manufacturer or vehicle designer.

4004. All navigation lights shall be tested and adjusted to ensure that visibility sectors comply with the applicable requirements of the International Rules for the Prevention of Collision at Sea, and that screening is provided to minimise the effects of glare and reflection upon vision of crew members.

Part B - Pre-operational - Prototype Vehicles and Installations. ^

4100. In addition to the tests and trials required by Part A of Division 4, before a prototype vehicle or prototype installation in a vehicle is operated for approval or certification, tests or trials shall be carried out to establish integrity of installations and compliance where appropriate with design data.

4101. Such additional tests as may be required shall be scheduled by agreement between the manufacturer and the certification authority in conjunction where appropriate with component manufacturers or other specialized testing agencies.

4102. Machinery.

Main machinery components of propulsion and lift systems shall be subjected, either separately or collectively, to such testing as may be required to establish structural integrity of the installed component or system, it's vibratory or oscillatory loading spectra, and the effects of such spectra on the vehicle structure and safe operation. Testing shall include, but not necessarily be limited to, that required by Section 792 of this Standard.

4103. Electrical Systems.

The normal electrical power generation and distribution systems are to be operated and subjected to sufficient testing to establish a representative electrical load analysis to which the systems will be subjected during all anticipated combinations of electrical loading.

4104. Fault Conditions.

All main and auxiliary machinery, fluid systems, directional control systems, and electrical power generation and distribution systems shall be subjected to such tests as may be necessary to determine that, under all reasonable fault conditions that may be experienced in service:-

1. Adequate indication is provided to crew members;
   
   
2. Any automatic function of the system consequent upon the fault operates correctly;
   
   
3. The fault and it's effects do not impair the safety of operation of other systems;
   
   
4. The fault can be contained without additionally impairing safety, by corrective measures.

4105. Special Tools and Equipment.

Where maintenance or servicing operations, or operation of the vehicle, depend for their safety upon the use of special tools or equipment designed and manufactured, or adapted, specifically for use on the vehicle, the safe operation of such equipment is to be demonstrated, and any limitations on it's use are to be recorded.

4106. Installations.

All equipments, systems and controls shall be operated according to agreed schedules in order to determine that all machinery and it's systems, controls, components and equipment may operate under all conditions for which they were intended within any prescribed limitations.

Part C - Operating Safety Trials - Prototype Vehicles and Equipment. ^

4200. An Air Cushion Vehicle of a model or configuration which has not previously been issued with a safety certificate permitting it's general use shall be subjected to a schedule of trials to determine any loading, operational or environmental limitations with which the vehicle type shall comply in order to provide the required level of safety in service.

4201. The schedule of tests shall attempt to demonstrate safety of operation of the vehicle and management of it's systems and controls in loading and environmental conditions up to and including those declared in the design specification. It is emphasised that any safety certification given will relate to the conditions achieved during the course of trials; all trials documentation duly authenticated by the representative designated by the manufacturer for the conduct of the trial and submitted in substantiation of claims for certification will be considered.

4202. For vehicles operating in the marine environment, quantitative results should be provided to demonstrate:-

1. Directional and speed control characteristics during low speed manoeuvring in the displacement mode, both hull-borne and cushion-borne;
   
   
2. Directional and speed control characteristics during transition to, and operation at, speeds up to the maximum for which certification is sought;
   
   
3. Turning circle diameters at all speeds, and associated roll stability;
   
   
4. Any limiting safe deflection of any directional control device, either when applied singly or in combination;
   
   
5. Normal and emergency stopping distances from pre-determined speeds up to the maximum for which certification is sought, when operating with zero hydrodynamic yaw angle;
   
   
6. Any limitations of the vehicle speed/hydrodynamic yaw angle envelope to be observed in order to maintain safe operation;
   
   
7. Any limitations of longitudinal c.g. position affecting safety of operation;
   
   
8. Any adverse longitudinal trim changes dependent upon aerodynamic or hydrodynamic velocity or wind or wave direction;
   
   
9. Vehicle response to a single failure of one propulsion main engine, one lift main engine, and one directional control device (other than a fixed-axis propeller), during turns in each direction;
   
   
10. Any adverse effects upon safe handling and control resulting from operation over shallow water.

4203. In addition to the results by section 4202, qualitative results should be provided to demonstrate:-

1. Adequate authority of directional control to maintain desired vehicle heading under normal operating conditions without undue control movements or operator fatigue;
   
   
2. Adequate authority to maintain vehicle longitudinal trim angle under all loading conditions within the operating envelope for which certification is sought;
   
   
3. Adequate control authority to maintain safety of operation with reduced capability subsequent to any one of the single failures examined in section 4202 (i);
   
   
4. Adequacy of outboard vision and transparency clearance systems for safe operation under all environmental conditions for which certification is sought, including operation at night where this is a certification objective;
   
   
5. Adequacy of visibility and accessibility of an instrumentation, displays and controls provided for crew members for safe operation and management of the vehicle and it's systems, under all lighting conditions;
   
   
6. Adequacy of all ventilation and environmental control systems provided;
   
   
7. Audibility of all internal communication and broadcast systems during normal vehicle operation;
   
   
8. Management of vehicle systems, and of vehicle control and handling with 50% (minimum of one) of electrical power generators inoperative.

4204. For amphibious vehicles, additional trials shall be conducted to demonstrate adequacy of control and any limitations required to maintain operational safety during transitions to and from solid and liquid surfaces, and during manoeuvring when overland.

4205. An evacuation trial shall be conducted, using evacuation procedures and facilities provided for emergency evacuation and using lifejackets and liferafts proposed and stowed in their normal positions. The trial shall be arranged to simulate as closely as practicable the activation of a fire alarm in a Designated Fire Zone and the subsequent initiation and completion of an evacuation. Personnel involved shall be crew members not more than those carrying out normally assigned duties of the vehicle in service, initially at their normal duty station; a number of representative passengers not less than 50% of the maximum complement for which certification is sought, distributed representatively in passenger accommodation, and observers from or representing the certification authority. The result of this trial shall determine any passenger loading restriction which may be required in complying with the evacuation time allowance provided for in Section 1004 of Division 1 of these Standards.

4206. In trials to determine the vehicle response and control subsequent to a main lift engine failure, in vehicle designs employing multiple lift fans and intakes, the adequacy of the intake closure on the failed lift fan intake to prevent total loss of cushion air shall be demonstrated.

4207. The vehicle shall be subjected to a towing trial, during which any limitations imposed by directional control characteristics when being towed in both the displacement and hovering modes at speeds up to the maximum towing speed for which certification is sought shall be determined.

4208. Any vehicle which is of a design which has previously been subjected to prototype safety certification trials, but which incorporates such changes to structure, machinery or equipment that may render invalid any results of such trials shall be subjected to additional trials to establish the effects of such changes upon safety certification.

4209. Instrumentation or recording equipment required for trials data gathering shall be installed such that the accuracy of normal vehicle instrumentation and displays is not impaired, and that crew members may perform their normal duties with minimal distraction.

4210. Vehicles engaged upon prototype safety certification trials shall carry two-way radio communication equipment capable of maintaining communication with local safety services and weather information facilities.

Part D - Operating Safety Trials - Production Vehicles. ^

4300. Every Air Cushion Vehicle shall be subjected to a schedule of trials which shall be agreed between the manufacturer and the certification authority. The trials schedule will require that the vehicle demonstrates performance, handling and control characteristics essentially similar to those previously established during trials of the prototype vehicle.

4301. In addition, every Air Cushion Vehicle will be subjected to a flotation trial, during which the vehicle is to be moored or anchored in water for a period of not less than 12 hours. During this trial, any automatic bilge pumping system is to be rendered inactive and upon completion, all watertight compartments shall be sounded and/or bilged. The source of any leaks resulting in an accumulation in any watertight space in excess of 100 1. shall be investigated and corrected, and the vehicle subjected to a repeat trial.

4302. Trials shall be conducted during vehicle operation of any installed radio-communication equipment and navigational equipment, instruments or aids with which the vehicle may be equipped to meet operational requirements for the service intended. Trials shall establish that the equipment may be operated safely without mutual interference, and without impairing the safety of operation of the vehicle and it's systems or the accuracy of any instrumentation or display.

Part E - Vehicles of other than Canadian Manufacture. ^

4400. Before any Air Cushion Vehicle which has been manufactured in a country other than Canada may be issued with an Inspection Certificate, the importer shall submit to the safety certification authority such technical data and certification as may be required to enable the degree to which the vehicle complies with these standards to be determined.

4401. Upon satisfactory evidence that the vehicle complies with these standards, safety certification trials may be required in order to confirm that the vehicle may safely operate in the intended Canadian environment. In establishing such confirmation, the certification authority may require modifications to the vehicle or it's installed equipments, or may revise any operating limitations or restrictions where such revision is essential for the preservation of the required level of safety.

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