Patrolling the EEZ

In addition to this equipment and its associated manpower, the system depended on secure 24-hour communications, and an organisation to coordinate air, sea, and land operations. In most countries, it was natural to turn to the armed forces to cobble together some form of coast-guard system, since they already had the communications and the organisational capability, and no urgent defence threat. On the other. hand, their existing aircraft and surface vessels have generally been found to be ill-suited to the task, and there may (as in the case of Australia) be legal problems in sailors arresting civilians. It is perhaps worth noting that the long-established US Coast Guard service, although a para-military organisation, comes under the Department of Transportation, not Defence.

In the case of Australia, fishing and illegal immigration have been the driving forces behind surveillance operations, although there are many other considerations involved. At a symposium organised by Hawker de Havilland in Sydney 1978 it was estimated that the Australian fishing catch was worth something in the region of $200m annually, involving 9,000 vessels representing a capital investment of $226m, and a work force of around 18,000, aside from those working at shore plants processing the fish. However, allowing for the activities of boats from Japan, Taiwan, and Indonesia operating within the Australian Fishing Zone (AFZ), and for some expansion by the domestic fishing industry, it was suggested that the potential annual value of the catch within the AFZ was probably closer to $500m, clearly a national asset worth protecting.

However, it is also recognised that health and quarantine considerations are potentially far more important than the direct benefit to fishing revenues. At the Sydney conference, the annual value of Australia’s sheep, cattle, pig and poultry production was put at $3,471m, of which $2,512m was exported. The introduction into Australia of exotic diseases affecting animals could thus cause considerable harm to the economy, as could pests and diseases affecting plants. Other important EEZ considerations include the smuggling of drugs and fauna, the detection of pollution that may threaten fisheries and beaches, the protection of offshore oil rigs against possible terrorist attacks, and search and rescue (which is jointly the responsibility of the Commonwealth and State governments). Whereas the protection of the fishing and farming industries can be allocated some direct monetary value, such matters as controlling the inflow of drugs cannot readily be given a price tag. It is nonetheless clear that failure to keep smuggling to a minimum could have very serious consequences for Australian society.

Since the 200-mile AFZ was declared on 1 November 1979, Australia’s efforts at patrolling and policing the zone have centred on the use of HAN S-2G Trackers and RAAF Dakotas based at Darwin, RAAF P-3 Orions making around-thecontinent tours from Edinburgh SA, and approximately 15 chartered light twin-engined civil aircraft, together with surface patrols and intercepts by the RAN’s 12 “Attack”-class patrol boats, which form three squadrons based at ·sydney, Cairns, and Darwin. These activities have been coordinated in Canberra by the ACSC (Australian Coastal Surveillance Centre), a part of the Department of Transport.

The RAN Trackers have now been withdrawn and replaced by the first of 10 GAF Searchmasters, three of which are to be operated by the Bureau of Customs. The “Attack”-class patrol boats are likewise to be replaced by the “Freemantle” class, of which 15 are on order and a further 10 are planned.

The Commonwealth review of national civil surveillance requirements that is curently in progress is expected to recommend further aircraft purchases in order to provide search capability at a greater range than the Nomad but at far less cost than the Tracker and Orion. The use of these military aircraft has doubtless provided some useful training for their crews, but chasing fishing vessels has little connection with the serious purpose of such aircraft, and they cannot be diverted indefinitely from their defence role. It is anticipated that the new aircraft will number five or six, and that they will have gross weights in the 20-ton class, ie the British Aerospace 748 Coastguarder, the Fokker F27 Maritime, or possibly the de Havilland Canada Dash 7 Ranger.

Scenario

Notwithstanding Australia’s 20,000 km coastline, the search effort involved in the maritime resources zone is kept within reason by the fact that the active areas for fishing, smuggling, illegal landings, etc, represent only a fraction of the total area, and that fishing activity is seasonal and can be regulated in such a way as to make violations relatively easy to detect.

In the days of the 12-mile limit, the objective was simply to exclude foreign fishing vessels from operating in Australian waters. In contrast, within the 200-mile zone the aims are to allow Australian vessels to harvest as much as they can, and license foreign vessels to catch whatever is left, consistent with the long-term conservation of resources.

Canada was one of the leaders in establishing means to regulate the activities of foreign fishing vessels. National fishing allocations are negotiated at government level, and within these allocations individual boat licences are sold, specifying exactly how much each boat is allowed to catch, and laying out detailed conditions and the penalties for infringements. These conditions include inspection on demand, and that the boat must carry a radar beacon and clearly visible markings. It must also report its position on entering and leaving the EEZ, and at daily intervals while within the EEZ.

With these provisions, it is relatively easy to keep track of licensed vessels. Given severe penalties for poaching or exceeding quotas (confiscation of equipment and possibly the vessel itself, coupled with the threat of harsh penalties on return to the port of origin), infringements are rare. In the case of Canadian fisheries surveillance, it is claimed that most violations are detected within one day of the start of fishing. An important element in the system is a computer operation termed FLASH (Foreign Fishing Vessels, Licensing And Surveillance Hierarchical Information System), which stores all relevant data. By this means each of the aircraft and search vessels is provided with a current list of the foreign boats that it can expect to encounter on its patrol.

Given such measures to control the activities of foreign vessels in the AFZ, a search of the active areas once weekly is probably sufficient to ensure a reasonable probability of detecting violations, although some reserve capacity will clearly. be needed in order to respond to other types of demand, eg when some source of intelligence indicates that a major smuggling operation is about to take place in a specific area.

The sea is normally searched by radar from a height of around 2,000 ft to allow visual identification, the rate of advance depends on the cruise speed of the aircraft and the density of vessels on the water. Given radar beacons on licensed boats, it may not be necessary to identify every target visually. Where a vessel is breaking regulations, its position is reported by radio, and modern cameras can provide evidence of the infringement, recording date, time, position, etc, on the edge of the film. The photograph will also indicate (in the case of a fisheries violation) the type of fishing in progress, and it may be possible to identify. Fish lying on the deck.

Although most fishing takes place in daylight, there is clearly a need for a night-time search capability for fisheries protection (most squid fishing is done at night) and other roles. At night it may be possible to identify a ship by means of the aircraft’s landing lights, but a searchlight is preferred by some operators. Flares can be used, but require the aircraft to gain altitude before release. For photographic evidence, the best form of illuminaion appears to be electronic flash. If required, this can be filtered to the near infra-red to give covert operation.

Comparison

In considering the most likely longer-range aircraft to complement the Nomad, the Dart-engined BAe 748 and Fokker F27 have already proved their merits in many years of operations, whereas the PT6-engined DHC Dash-7 is relatively new, having entered service only in 1978. The BAe 748 and F27 cost approximately the same, while the Dash-7 is cheaper, possibly subsidised by Canada’s government. In Australia the 748 is operated by both the RAAF (eight navigation trainers at East Sale, Vic, and two VIP transports at Fairbairn, ACT) and the RAN (two electronics surveillance aircraft at Nowra, NSW), both services carrying out their own overhaul work as necessary. The F27 is operated by Ansett (with a total of 19), Bush Pilots (one), East-West (10), MacRobertson-Miller (one), and TM (10).

Comparing the performance of these aircraft in their Coastguard, Maritime, and Ranger versions, the two Dartengined types are very similar, while the Ranger is somewhat slower, but is more of a STOL machine. In principle, the two high-wing aircraft should enjoy less drag than the low-wing Coastguarder, but the effect of the cleaner wing-body junction seems to· be_ almost counterbalanced by the external tanks of the Maritime and outweighed by the drag of the Ranger’s two extra engine nacelles.

They have virtually identical operating empty weights, the Coastguarder with 13,207 kg, the Maritime with 13,311 kg, and the Ranger with 13,172 kg. However, the Coastguard has rather more internal fuel, with 10,047 litres compared to 9,326 for the Maritime and 9,350 for the Ranger. Adding the corresponding fuel weights to the OEW thus makes the Coastguarder the heaviest by a slight margin, with a gross weight of 21,145 kg, compared to 20,678 kg for the Maritime and 20,558 kg for the Ranger. At these take-off weights on a standard day the Coastguarder will clear a 15 m obstacle in approximately 915 m, the Maritime taking around 1050 m to the same height, and the Ranger beating them both with a distance of only 800 m. This STO performance is not as good as the 600 m take-off distance of the GAF Searchmaster, but it is quite remarkable for an aircraft of this class. The Ranger presumably achieves its STO by virtue of long-span flaps giving efficient deflection of the four slipstreams, and by its slightly lower wing loading, approximately 257 kg/sq m, compared to 275 for the Coastguarder and 295 for the Maritime.

All three have similar amounts of power: two 2,280 shp Darts in the Coastguarder, two of 2,370 shp in the Maritime, and four PT6s of 1,120 shp in the case of the Ranger. However cruise speeds vary according to wing loading and general cleanliness of the airframe, the 245 knot Coastguarder being beaten by the 256 knot Maritime, with the Ranger tailing behind at 233 knots, despite avoiding the drag of a ventral radome. This pecking order is, however, reversed when the criterion is time on station: at a radius of 400 nm the Ranger can patrol for approximately 8. 5 hr, whereas the Coastguarder appears to be limited to around 7. 75 hr and the Maritime to perhaps 7. 0 hr. At 800 nm, the Ranger and the Coastguarder have endurances in the order of 4. 5 hr, with the Maritime offering perhaps 3. 5 hr. All these endurances are for patrol at 2,000 ft, and it should be noted that the Ranger figures refer to slower speed, ie 128 knots, compared to 145 knots for the two twins. However, such comparative data can only give a general guide since some of the sales brochures supplied to this writer by the manufacturers leave a great deal to be desired.

Turning to radar performance, both the Coastguarder and the Maritime accept the drag penalty of ventral radomes in order to have 360-degree cover, whereas the Ranger (which was originally projected with a similar installation) now has a nose radome giving 180-degrees. Although in principle this sweeps just as wide an area as a full-circle sweep, it is clear that from practical search considerations a ventral radome is the preferred solution. The Canadian manufacturer opted for a nose radome on the basis of reducing drag and fuel consumption, and eliminating radome damage when operating from gravel strips.

The Coastguarder is currently equipped with the MEL Maree radar, although the more sophisticated MEL Sea Searcher (as fitted to the Sea King 5) is also available for approved customers. The standard fit on the Maritime is the Litton APS-504 (V)-2 as on the Searchmaster L. The Ranger was originally to have had Litton LASR-2, but more recently it is quoted as having a Texas Instruments radar. All of these radars appear to be capable of detecting a trawler with an equivalent reflecting area of 200 sq m at a distance of approximately 40 nm in sea state 3-4. On the information provided in the aircraft sales brochures it is impossible to say which radar provides the longest detection range. However, it seems unlikely that the aircraft will be chosen for its standard radar fit, since the manufacturers can change the equipment to suit customer requirements, although it is possible that only the Coastguarder can accommodate the deeper radome of the Marec radar (thanks to its unrivalled 122 cm ground clearance).

Any purpose-designed maritime search radar will provide a beacon-interrogation mode, a choice of pulse widths (short for penetration of sea clutter and good short-range definition, long pulses for good long-range performance), and a variety of display modes. Aside from the traditional PPI (plan position indicator) display with the aircraft fixed in the centre and the radar returns moving, it will also provide a ground stabilised mode, in which data from the navigation system is used to fix the ground returns and the aircraft position moves across the display. This enables the operator to mark target positions on a transparent overlay showing the adjacent coastline. The ground-stabilised mode can be offset (ie, with aircraft off the screen), and the display can be limited to a sector-scan to increase the probability of detection. Although all the radars mentioned above will probably give all these facilities, it is noteworthy that the Coastguarder’s Maree provides these displays on a 43 cm screen, whereas the Maritime’s APS-504 has only a 17. 8 cm screen. The larger screen is naturally more conducive to effective operation.

Before leaving the subject of avionics, it may be noted that there are basic differences between the main contenders in terms of primary navigation equipment. The Coastguarder combines Doppler tactical navigation with Marconi Omega-VLF general navigation, the latter being chosen for low cost and easy maintenance, and better accuracy (2-5 nm CEP) on long flights. The Maritime uses a Litton LTN-72 inertial system, chosen for high accuracy (approximately 1 nm/hr) and worldwide use. However, one might question how well Doppler works at steep bank angles, whether Omega stations give 24-hour coverage around Australia, and whether inertial systems retain their accuracy in a constantly manoeuvring aircraft. Once again, the solution appears to be to choose the aircraft on other criteria and specify the navigation system of your choice.

Since equipment is largely interchangeable, perhaps the best approach in making a comparison is to stick to the fundamentals of the aircraft and discuss each one in turn.

The BAe Coastguarder provides a good combination of speed and endurance, and it is a strong aircraft, well suited to unpaved runway operation. It appears to lead first in the radar search mission by virtue of its unrivalled 43 cm display. Secondly, it is almost certainly best in maintenance costs: BAe claim an advantage of approximately 20 per cent over the Maritime, due to the latter’s problems of bonded structure inspection and detecting leaks in the pneumatic system, and its less robust undercarriage. Thirdly, the Coastguarder appears to be more flexible in its application and development potential. It has a large rear door for parachuting heavy loads (eg, large rescue dinghies) and can rapidly be converted to transporting passengers or cargo, eg, in taking ground crew and spares to a forward base. It has provision for four underwing pylons, and BAe is obviously well qualified to develop Coastguarder for the ASW or anti-shipping strike missions. To these advantages might be added the fact that the AMF already flies and overhauls the BAe 748, and it seems likely that (in the short term, at least) the AMF will operate whatever long-range complement is chosen for the Nomad.

The Coastguarder’s disadvantage is its low wing, which somewhat restricts visual search, although this is only a secondary mode of operation. Conversely, when circling a vessel for visual identification, the low-wing aircraft may be better off than its high-wing competitors. Moreover, in the unlikely event of a ditching, the low-wing aircraft will float relatively high in the water, facilitating crew escape.

The Fokker F27 Maritime combines the visual search advantage of high wing with the highest speed of the trio, but it has the shortest endurance, due to its limited fuel volume, and appears to be the least well suited to short, unpaved strips. However, it leads in sales, with three for Spain, three for Philippines, two for Peru, two for the Netherlands, and one for Angola. At the time of writing, no Coastguarder has been sold, and nothing has been heard recently of the Canadian Coast Guard order for two Rangers. If an Australian Coast Guard service should be established under the Department of Transport, then Maritimes could be serviced and overhauled by TAA or any number of operators.

The DHC Dash-7 Ranger is even more of an STOL aircraft than the Coastguarder, and it eliminates the risk of gravel damaging a ventral radome, but it is debatable whether this short, rough strip capability is really important in a long-range aircraft. It is claimed to have a quieter cabin than either twin-Dart aircraft, but the European manufacturers say there is little difference in noise level if their aircraft are throttled back to Ranger speeds. The Canadian aircraft is alone in having four engines, which might be argued to be safer in continuous overwater operation. However, with an unscheduled shutdown rate of one in 100,000 hours for the Dart, this point seems academic.

The Ranger has the disadvantage of a radar scan angle restricted to 180 degrees. It is also somewhat slower than its rivals and probably has higher maintenance costs due to its four engines, the shorter TBO of the PT6, and the fact that having the power does not halve the overhaul cost. The Ranger is also at a disadvantage in being new to Australia.

As well-established aircraft the two European types are likely to be favoured, with the final choice perhaps determined by who is to operate them, ie, military crews or civilians.