cules aircraft were equipped with the usual radar and loran receivers 

 and additionally with the new Doppler Navigation System. The goal 

 of navigational accuracy from Ice Patrol aircraft is plus or minus 

 1 mile. The navigation by loran does approach this accuracy in some 

 areas, but in many areas on the Grand Banks and vicinity this accu- 

 racy cannot be attained. The Doppler Navigational System was 

 expected to solve the navigation problem, but after 1 year's use on 

 Ice Patrol, it must be stated that it has been a disappointment thus 

 far, with hopes for hnprovement. 



Another problem that has plagued Ice Patrol for many years is the 

 inability to identify radar targets during marginal or poor visibility. 

 Many flights must be made in marginal weather and some with poor 

 visibility. Flight tracks of the Ice Patrol flights are usually spaced 

 25 miles apart, which is a compromise between maximum area cover- 

 age and maximum probability of detection. Thus a visibility of at 

 least I2V2 miles is required to obtain 100 percent visual effectiveness. 

 Often this visibility is not obtained (see table 2) , with reliance shifted 

 to radar. The altitudes flown by Ice Patrol aircraft vary from 500 

 to 2,000 feet, and from these altitudes even the smaller bergs can 

 usually be picked up by radar up to 15 miles. Radar targets can then 

 be identified by diverting from the planned track unless the ceiling- 

 is below 500 feet. With ceilings frequently below 500 feet, the 

 inability to identify a radar target as a fishing trawler or an iceberg 

 becomes a serious handicap. International Ice Patrol has tested a 

 few detection-type instruments in flight with some success; however, 

 the tests were not deemed sufficiently promising due to excessive costs 

 of purchase and installation. One such instrument called the bolo- 

 meter was tested in 1954, but could not detect ice in fog. It is planned 

 to install airborne radiation thermometers, which are the successor to 

 the bolometer, aboard Ice Patrol aircraft for the 1964 ice season for 

 use in recording the surface sea temperatures along the track to enable 

 location of the Labrador and Atlantic Currents and branches. The 

 use of this instrument is expected to assist in berg drift and deteriora- 

 tion forecasting and in flight planning. Further research has been 

 conducted on instruments tested by the Ice Patrol, and when the 

 promise of success justifies the effort and expense, the equipment will 

 be purchased and installed with the objective of improving the effi- 

 ciency of the International Ice Patrol and providing the best possible 

 services at the lowest costs. 



Five observation flights were made from 13 January to 27 February 

 by the Air Detachment to determine the southern limit of ice and to 

 enable deciding when to commence the International Ice Patrol. 

 Two of these flights were made in a survey north along the Labrador 

 coast to Baffin Island and return for the main purpose of determining 

 the 1963 iceberg potential. Five observation flights were made by 



