EMS Helipads associated with Victorian hospitals are principally used by helicopters in the statewide Air Ambulance Victoria fleet, or those under arrangements with AAV. In general, these are high performance twin-engine helicopters that are capable of operating in accordance with Performance Class 1 criteria.
ICAO Volume II of Annex 14 to the Chicago Convention defines the physical layout of helipads. This section of these guidelines presents the primary characteristics of hospital helipads.
There are three principal elements required to provide and operate a helipad that is suitable for the types of helicopters used by AAV:
The layout of these components is shown below:
The specific marking for helipads at hospital sites is a red H on a white background.
Offsite helipads are generally marked with a white or yellow variant of the standard H marking. For such sites that are principally used by air ambulance helicopters, consideration should be given, in consultation with the Manager AAV, to applying the standard hospital helipad marking.
The dimensions of the hospital helipad marking are shown below:
The marking is primarily used as the aiming point for landings and is therefore to be located centrally within the FATO.
The helipad markings should be a highly reflective paint mixture containing glass beads or similar. The reflective paint provides visual guidance to the helipad at night or low light conditions, when the marking will be reflected in the beam from the helicopter floodlighting equipment.
Public access should be restricted to the helipad as a safety measure. Where it is not practical to restrict public access, consideration needs to be given to the identification and marking of a public safety area around the helipad. The minimum separation between the public area and the centre of the helipad should be 30metres.
Vehicular access should be provided to enable patients to be safely transferred to and from road ambulances. The access link between the helipad and the adjacent road network should provide a smooth surface suitable for the transportation of patients.
Lighting requirements for EMS helipads will depend on the location of obstacles and the availability of a suitable power source.
The type of lighting system chosen will depend on the projected usage and should be selected in consultation with the Manager, AAV.
Options available for helipad lighting include floodlights or ground level lights. Floodlighting is used in conjunction with retro-reflective markings. Ground level lights identify the edge of the LLA and the FATO. Power sources can be mains supply or solar powered.
Air ambulance helicopters are equipped with high-powered floodlights that complement the helipad lighting systems.
In order to reduce additional obstacles around the helipad, where possible, floodlighting should be combined with a wind indicator or on nearby structures. The distances between the helipad and any adjacent floodlights may need to be considered in determining the suitability of floodlight options.
A wind speed and direction indicator should be provided at each hospital helipad to provide a visual guide to the wind speed and direction. The direction indicator should be illuminated to be visible by approaching aircraft.
The preferred location of the wind indicator is adjacent to the helipad on the upwind side of the primary operating direction.
The wind indicator and pole should be located outside of the helicopter flightpath envelope and clear of turbulence-affected areas. The windsock should normally be 2.4 metres long with a diameter of 0.6 metres as nominated by ICAO.
Details of the criteria for windsock lighting are presented in Section 9.6 of the Civil Aviation Safety Authority (CASA) Manual of Operational Standards Part 139.
Two 4.5 kg CO2 fire extinguishers should be available as close as practicable to the helipad.
The helipad dimensional requirements presented in this part of these guidelines relate to helipads that are used by one helicopter at a time.
The spatial requirements for helipads intended to be used by more than one helicopter or to accommodate parked helicopters require further consideration beyond the scope of these guidelines. For further advice on this issue please contact the Manager, AAV.
The EMS helipads described in these guidelines are intended and designed for use by helicopters operating in Visual Meteorological Conditions (VMC).
The use of a helipad in Instrument Meteorological Conditions (IMC) and the use of Global Positioning System (GPS) based instrument approaches under the Instrument Flight Rules (IFR) require additional consideration beyond the criteria presented in these guidelines. For further information contact the Manager, AAV.
The physical characteristics of the principal AAV helicopter fleet are set out in Appendix C.
However, in an emergency, alternate helicopter types such as those serving military or offshore facilities, may use an EMS helipad. This will require additional consideration beyond the criteria presented in these guidelines. For further information contact the Manager, AAV.
A flightpath is the normal route taken by aircraft after lift off or prior to landing.
The direction and dimensions of flightpaths to and from a helipad need to be defined as part of the helipad planning process. The flightpath is defined in 3 dimensions in relation to helipad described in this guideline:
For maximum use of the helipad, a number of flightpaths are needed to accommodate a range of operating conditions. Flightpath selection is dependent on weather and environment considerations such as prevailing wind conditions, the likelihood of excessive turbulence and the location of existing and potential future obstacles. The minimum number of flightpaths must comply with statutory and guideline requirements.
Ideally, the range of flightpath directions available around a helipad for takeoff and landing approaches would extend through 360º. Such operational flexibility is rarely available however, particularly around hospital sites, and flightpath options need to consider factors particular to each site. The planning and orientation of the helicopter flightpath will also need to consider the land use zoning in the vicinity of the helipad. Hospitals are frequently located in areas where adjacent land use zonings permit developments up to two or three storeys. Such developments and the associated vegetation frequently create a confined area for helicopter operations.
Minimum dimensions for helicopter flightpaths are prescribed by ICAO and adopted by CASA. The general shape, in plan view, of the flightpath envelope for air ambulance helicopters is a trapezoid extending from the boundary of the FATO area to a width of 150 metres. The cross-sectional dimensions of the flightpath envelopes for air ambulance helicopters have been developed after consideration of the following principles:
Accordingly, to provide a suitable clearance over such obstacles, flightpath envelopes for EMS helipads incorporate a minimum height of 12 metres above the helipad for the initial takeoff distance of 250 metres. This criterion is based on the ability of EMS helicopters to operate with an increased Critical Decision Point (CDP) elevation. The CDP applies to the landing (LDP) and the take-off (TDP) phases of flight.
The CDP is used to determine the action to be taken in the event of one engine becoming inoperative (OEI). If the OEI event occurs below the CDP height, the helicopter lands at the helipad, and if above the CDP, an OEI fly-away is completed.
The helicopter has reduced performance during OEI operations and the provision and protection of an obstacle-free fly-away area is essential for the safe operation of the helicopters. Flightpath envelopes are defined in these guidelines to identify volumes of airspace around a helipad that need to be protected against the future encroachment of obstacles. The extent of such envelopes therefore extends to the regions defined by the nominal location of the flightpath envelope at a height limit of 40 metres, the general height of development outside the high-rise city regions.
In general terms, helicopters operating under the Performance Class 1 criteria will attain a height of 40 metres within 900 metres of the helipad location and this dimension has been adopted for hospital helipad flightpath envelopes. A plan view and section through the take-off profile is shown in Figure 4. A plan view and section through the approach profile is shown in Figure 5.
Helicopter operating directions are dictated by the prevailing wind speed and direction. The usability of hospital helipads needs to be assessed with reference to the crosswind and tailwind limitations applicable for Performance Class 1 operations.
Reference to the Flight Manual Supplements for the Bell 412EP and the AS365N3 helicopters indicates a nil tailwind and 10 knot crosswind limits apply in considering the effects of prevailing winds for these aircraft.
Records of wind data are available from the Bureau of Meteorology for a number of sites throughout Victoria.
Computer modelling of wind data should be undertaken. There is a range of computer models available, however CASA has adopted the meteorology module of the CSIRO’s The Air Pollution Model (TAPM) computer program. TAPM uses records of synoptic meteorology in combination with terrain and vegetation databases to provide average wind data for a specified location.
Helipad studies need to determine the potential usability of a helipad with respect to the ambient wind conditions and the range of flightpath orientations available after existing and potential obstacles have been considered.
A helipad should have two approach surfaces, separated by at least 150º. Additional approaches may be provided, the number and orientation ensuring that the helipad usability factor will be 98% in recognition of the need to have the helipad available for medical emergencies.
In situations where the combinations of prevailing winds and obstacles in the vicinity of the helipad prevent the target usability being achieved, the hospital should make alternate air access arrangements.
The potential for turbulent wind conditions in the vicinity of the helipad and associated flightpaths may need to be considered and discussed with the Manager, AAV. Where it is clear that issues of this nature are significant or may affect the safe operation of the air ambulance, more detailed information such as laminar flow studies or wind tunnel testing may be required.
These helipad guidelines relate primarily to ground level facilities in areas where surrounding development is unlikely to exceed a height of 40 metres above the helipad elevation.
Specialist consideration of flightpath definitions is required for locations where a rooftop helipad is contemplated and in locations where obstacles may exist with a height in excess of 40 metres above the helipad elevation. Such considerations might include location of rooftop exhaust and air conditioning systems, wind turbulence and surrounding tall structures.
Takeoff Flightpath Envelope
Approach Flightpath envelope
EMS helicopter flightpaths need to be protected against obstacle intrusion to ensure the continued availability of the helipad.
Protection of the flightpath areas is achieved by incorporating details of the flightpath envelopes within the relevant municipal planning schemes. The mechanism adopted to achieve the required level of protection is the Design and Development Overlay (DDO).
An overlay is a standard provision in Municipal Planning Schemes that ensures the important aspects of the land are recognised. The DDO enables the extent of flightpaths to be identified with a development height restriction placed over the area.
In general three DDO areas are defined for each EMS helipad – one for the area within the initial 250 metre, one for the subsequent take-off climb area and one for the approach area.
In general, the DDO areas will provide maximum flexibility for helicopter operations and for the consideration of any referred development applications.
Development proposals within the DDO area that exceed the nominated height limit are to be referred to DH by the Council. DH shall consult with the Manager, AAV and the Helipad Manager for further consideration of:
Proponents of referred developments will need to:
Development proposals in areas where multiple flightpath orientations have been defined may be successful on referral provided their resultant effect will not adversely reduce the usability or safety of the helipad. Development proposals that would adversely reduce the usability or safety of the hospital helipad will not be supported.
There is currently no specific land use zoning requirements for a hospital helipad.
Consideration should be given to rezoning a helipad area where the helipad location is within a Public Use zone and it is proposed to implement public access restrictions in the vicinity of the helipad.