Monday, September 27, 2010

Helicopters

Helicopters introduce new hazards into exploration that are not encountered in general aircraft operations. Their versatility means unusual hazards and risks, which must be controlled by careful selection of contractors and equipment, competencybased training for employees, and strict compliance with rules and operating procedures. Margins for error are small. All operations must be conducted in accordance with the relevant CASA requirements. While the helicopter pilot is the key person in the safety chain, and must remain in total charge of the aircraft, all those involved in helicopter operations have important roles to play.

Selection of contractors and helicopters
When selecting contractors and types of helicopter to be used, consider:
• what will the helicopter be used for, e.g. ferrying staff to and from site, transporting equipment, slinging drill rigs and gear, undertaking aeromagnetic surveys, etc.
• seating capacity, average and maximum loads to be carried, range required, terrain to be covered
• contractor, pilot and engineer experience, reliability and record
• records of routine helicopter maintenance checks
• liaison between contractor and exploration company so that each other’s needs are fully understood
• servicing and fuelling arrangements
• radio and communication requirements.

Control of helicopter operations
The pilot is in command of operations affecting the helicopter, but total cooperation is needed from all those using it. Important issues are as follows:
• The pilot is the sole arbiter of safety. There must be no harassment, coercion or encouragement to act against the pilot’s judgment.
• Passengers must comply with the pilot’s briefings concerning in-flight procedures, including emergencies, embarking and disembarking, and general safety.
• The pilot must be briefed on passenger numbers, loads to be moved and flight path hazards.
• A competent experienced person must be appointed to be in charge of ground and helipad operations.


Helicopters are a valuable aid to exploration

Helipad safety
Helipad requirements vary according to types of helicopter, frequency of landing, terrain, vegetation and type of work to be carried out. Helipad safety must be controlled by a competent experienced person, who must have full authority on the ground. Reference should be made to CASA’s Civil Aviation Advisory Publication No. 92-2(1) Guidelines for the establishment and use of helicopter landing sites.

Points to be considered include the following:
• Size of helipad must be fully discussed with the contractor and pilot, taking into account the helicopter type and size, and the need for slinging loads.
• Good all-round clearance is required for manoeuvring of helicopter and loads.
• Vegetation must be sufficiently cleared to allow room for tail rotors and for approach and departure. A fully loaded helicopter may not be able to take off vertically. Dense low vegetation may absorb the downdraft and affect lifting ability.
• Touchdown area must be clearly marked, and any markers securely fastened down so they do not blow into rotors.
• Helipad design must suit local prevailing winds.
• Wind speed and direction indicators should be erected at base camp helipads.
• Fuel must be stored at a safe distance from the helipad.
• Helipad must be kept clear of unauthorised persons, equipment and loose or light objects.
• Only an authorised person is to signal the pilot, except in an emergency.
• Everybody must keep clear of the tail rotor at all times. They must not approach the helicopter when the main rotor blades are in motion unless authorised.
• Rotors can flop excessively in gusty winds.

Embarking and disembarking
Embarking and disembarking procedures vary according to the landing site. General rules include the following:
• Wait until the pilot gives permission before approaching or leaving the helicopter.
• Always approach and leave from the front, and remain in the pilot’s line of vision and in the 10 to 2 o’clock position.
• Never walk behind or under the tail, even when the rotors are stopped
• Approach and leave in crouched position, holding on to loose clothing and equipment.
• Always secure doors and harnesses when leaving.
• Do not jump on or off the helicopter. If the helicopter is hovering, transfer weight gradually to avoid suddenly upsetting the balance of the machine.
• Firmly fasten hats or safety helmets or carry them in the hand.
• On sloping ground approach and leave from the downhill side, to avoid the main rotor.
• Provide survival kits and communications systems at drop-off points in case the helicopter cannot return.

Loading and unloading
General rules for loading and unloading include:
• keeping landing site clear of loose articles
• carrying tools at waist height, not carrying anything on the shoulders, not throwing articles in or out of the helicopter
• using two people to carry long items and carrying them horizontally
• accurately assessing load weight, including an allowance for reduced lifting capacity at high altitude
• checking goods to be loaded with the pilot, especially batteries, fuel, LPG, etc. Hazardous cargo must be identified and packaging requirements adhered to. Slinging loads beneath the helicopter is a specialised operation subject to Civil Aviation Order 29.6 issued by CASA. Sling loading may only be carried out if:
• the helicopter has an approved supplementary flight manual detailing how the operations will be carried out
• slinging is in accordance with the manual
• the pilot has been trained and certified and has an endorsed licence for sling loading
• passengers other than flight crew or those essential to slinging are not carried
• all personnel are suitably briefed by the pilot beforehand
• only those authorised by the pilot are to attach and detach slings
• all precautions are taken by the pilot to ensure the safety of people on the ground
• unusual items, especially long items, are properly prepared for slinging.

Signals and communications
Universally accepted hand signals exist for communication between ground and helicopter pilots. These include signals for helicopter movements, landing, slinging, winching loads, and clear to start engines. Signals should only be given by trained and authorised persons, except in an emergency, but it is essential that all of the exploration crew are familiar with them.

Ground/air/ground radios are increasingly used for direct communication between pilot and ground crews. Procedures for this form of communication should be properly established and used. Do not rely on the helicopter radios as the sole means of communication. Passengers should not be dropped off at isolated points or unscheduled locations unless they have a survival kit and means of communicating with a base or emergency service, preferably by radio.

Operations
Points to be considered before starting exploration work include:
• keeping copies of work area maps on the helicopter and at the base camp
• leaving food, water and a radio communications system with everyone dropped off at a remote site
• ensuring that people dropped off know where they are before the helicopter leaves
• if people are walking from the landing site, fly the route to be traversed beforehand. People should carry emergency rations, signalling equipment, etc. at all times.

Emergencies
Emergencies can involve incidents with the helicopter itself or using the helicopter for evacuation of injured people. Points to be considered for helicopter emergencies include:
• provision of survival kits containing water, food, tents, life jackets, etc. on the helicopter
• first aid kit, compass, maps, signalling equipment, distress flares
• emergency locator beacon with both impact and manual switches
• firefighting equipment on the helicopter and at the helipad
• provision of survival kits and emergency communication to all persons dropped off at isolated or unscheduled locations.
Factors to be considered before transporting injured or sick people, which may adversely affect the patient, include:
• atmospheric pressure changes, which may cause severe pain to ears, sinuses, etc.
• turbulence and vibration causing further pain or injury to those with fractured bones or internal injuries
• noise causing distress to those with head injuries.