April 29, 2001 



Description of the Experiment . The goal of the test conducted on April 29, 2001 was to 

 determine the effect of varying the gain setting on the ability of the MSS 5000 to display 

 icebergs. Wind and sea height were approximately 25 KT and 1 .5 meters, respectively. 

 The ice targets included one 34 meter-long iceberg (small, non-tabular) and two nearby 

 growlers (< 15 meters). The search pattern was simply a series of boxes flown at an 

 altitude between 6000 and 8000 feet around the targets at ranges varying from 5 NM to 

 15 NM from the icebergs, with most of the detection opportunities occurring at a distance 

 of about 10 NM. 



Results . Although the target image quality (target brightness and definition) was best at 

 high gain settings, the small iceberg was detected on 19 of 19 opportunities, without 

 regard to the gain setting. The two growlers were detected on 27 of 38 opportunities 

 (71%). Most of the missed detection opportunities (7 of 1 1) were on east-west legs, 

 where the radar was looking across wave trains, which can obscure small targets. The 

 remainder of the missed detection opportunities for the growlers (4 of 1 1) were at the 

 longest range (15 NM) or lowest gain setting (5%). 



Commence 



test pattern 



~1730Z 



7, 11,15-«- 



End test 



pattern 



~1930Z 



_L 5,9, 

 13,17 



Wind (-25 KT) and 

 waves (-1.5 meters) 



8,12, 16 



Initial 

 1 detection 

 -1400Z 



Figure 5. Test pattern and iceberg distribution for the April 29, 2001 evaluation. 

 Numbers in red indicate detection opportunity. 



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