Thus, while aircraft were infi- 

 nitely more effective than sur- 

 face vessels in conducting 

 large scale visual reconnais- 

 sance during good flying 

 weather, during poor weather 

 the surface vessel had the 

 advantage because of its sur- 

 face radar ... and the Grand 

 Banks area is renowned for 

 poor weather. However the 

 practice of routinely using sur- 

 face patrol vessels to supple- 

 ment IIP aerial reconnais- 

 sance was short lived, ac- 

 knowledging the overall supe- 

 riority of aerial reconnais- 

 sance. Since 1950 surface 

 patrol vessels have been em- 

 ployed during only 5 seasons 

 (1957. 1959, 1972, 1973, and 

 1980). Clearly IIP reconnais- 

 sance is highly dependent on 

 Coast Guard aviation. In 1983 

 the use of Side Looking Air- 

 borne Radar (SLAR) was in- 

 corporated into IIP reconnais- 

 sance. SLAR has proven it- 

 self to be an excellent tool for 

 the detection of icebergs. It 

 also provides some ability to 

 discriminate between icebergs 

 and vessel targets. SLAR is 

 essentially an all-weathersen- 

 sor, although moderate to se- 

 vere air turbulence drastically 

 limits its usefulness. Each 

 present-day IIP aircraft is 

 SLAR-equipped: theHC-130 

 aircraft with a model AN/APS- 

 135; the HU-25B with model 

 AN/APS-131, part of the 

 AIREYE system. The intro- 

 duction of this sensor.coupled 



with improved ability to predict 

 iceberg drift, precipitated a 

 change in the strategy for 

 aerial reconnaissance. Be- 

 fore 1983 aerial surveillance 

 was accomplished by a de- 

 tachment continuously de- 

 ployed to the ice patrol area 

 throughoutthe ice season and 

 flying on an average of about 

 every other day. Since SLAR 

 became the primary iceberg 

 sensor, the ice reconnais- 

 sance detachment deploys to 

 its Canadian base approxi- 

 mately one out of every two 

 weeks, flying every day when 

 deployed. This approach al- 

 lows use of aircraft supporting 

 IIP to more readily support 

 other Coast Guard missions 

 as well. Using SLAR atypical 

 HC-130 patrol will fly seven 

 hours covering around 1700 

 track miles and a 27,000 

 square mile expanse of water. 

 The more range-limited HU- 

 25B covers a smaller area but 

 usually can conduct twothree- 

 hour patrols daily. 



In addition to their ice- 

 berg surveillance role Coast 

 Guard aircraft also serve as 

 platforms from which IIP con- 

 ducts "airborne oceanogra- 

 phy". From HC-130 aircraft 

 IIP deploys satellite tracked 

 drifting buoys which help de- 

 fine the ocean currents in the 

 ice patrol area. This near real- 

 time information is pivotal in 

 the accurate prediction of ice- 

 berg drift. From both the HC- 



130 and the HU-25 aircraft, 

 IIP deploys Air deployable 

 expendable Bathy-Thermo- 

 graphs (AXBT) which deter- 

 mine the ocean surface tem- 

 perature and thermal structure 

 of the water column. This 

 information is used to predict 

 iceberg deterioration. The 

 oceanographic information 

 acquired in turn helps limit the 

 amount of iceberg reconnais- 

 sance which is necessary. 



Since 1946 Coast 

 Guard aviation has played an 

 increasingly more important 

 role in the conduct of the IIP 

 mission. Today IIP is highly 

 dependent on Coast Guard 

 fixed wing aircraft. With the 

 outstanding support provided 

 by Coast Guard aircraft and 

 those who operate them the 

 Coast Guard has been able to 

 increase the effectiveness and 

 efficiency of the IIP service it 

 provides for mariners. 



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