Table 2 



Calculated Detection Ranges for Platform FP-1 

 Platform Data: Fixed, production^ four legs - 10 ft diarnete; 

 Prime power ~ gas turbine, water depth - 60 feet 



Frequency 



40 



Hz 



630 



Hz 



2000 



Hz 



5000 



Hz 



Source Level (1/3 Octave Band at 1 Yard) 



137 dB re 1 micropascal 



124 



118 



117 



Case I: Optimal Propagat ion (Cylindrical Spreading) 



Animal Listening Assumption 



A. Good Detection B. Conservative Detection 

 (1/3 octave crit, band) (100 Hz crit. band) 



Ambient Noise Condition Frequency Detection Range Frequency Detection Range 



1. 



High Ambient 



40 



Hz 



15 



Kyd 



7, 



.4 



nm 



40 



Hz 



1, 



,5 



Kyd 



0, 



,74 



nm 



2. 



Medium Ambient 



40 



Hz 



120 



Kyd 



59. 



.0 



nm 



40 



Hz 



12. 



,0 



Kyd 



5, 



.90 



nm 



3. 



Low Ambient 



40 



Hz 



600 



Kyd 



296, 



.0 



nm 



40 



Hz 



60, 



.0 



Kyd 



29. 



,60 



nm 



Case II: C onservative Propa g ation (Spheri c al Spreading) 



Animal Listening Assumption 



A. Good Detection B. Conservative Detection 

 (1/3 octave crit. band) (100 Hz crit. band) 



Ambient Noise Condition Frequency Detection Range Frequency Detection Range 



1. High Ambient 40 Hz 130 yds 0.60 nm 40 Hz 40 yds 0.02 nm 



2. Medium Ambient 40 Hz 350 yds 0J,7 nm 40 Hz 110 yds 0.05 nm 



3. Low Ambient 40 Hz 800 yds 0.39 nm 40 Hz 250 yds 0.12 nm 



G-42 



