OneShot
05-29-2005, 02:33 PM
This is about the formula for calculating the speed of a contact from the P-3C OWTOP Manual, page 24.
For this forumla to work you need two successive contact positions, for example two MAD returns. Now place the cursor on the first MAD contact and hit "R" - without clickin draw a line to the next contact and read out the distance between those two. Thats the distance ... for the time you need to put down markers with the time when this position was marked on the NAV map (check the manual how to do that). Means both Markers you used should have a time attached. The difference in minutes between those two markers is your time in the formula.
Example :
First contact at 1235, second contact at 1237 = 2 minutes between them. Distance measured between those two is 1000yds. Divide the Distance by the time means 1000yds by 2 minutes. Multiply the result with 60 (for 60 minutes = 1 hour). The last step is to divide that result by 2025 (because we are using yards for distance and 2025 yds are 1nm). The result would be 15(kts).
Just the numbers :
1000 / 2 = 500
500 * 60 = 30000
30000 / 2025 = 15
You can use whatever time lies between your two positions, just the example uses 2 minutes.
For this forumla to work you need two successive contact positions, for example two MAD returns. Now place the cursor on the first MAD contact and hit "R" - without clickin draw a line to the next contact and read out the distance between those two. Thats the distance ... for the time you need to put down markers with the time when this position was marked on the NAV map (check the manual how to do that). Means both Markers you used should have a time attached. The difference in minutes between those two markers is your time in the formula.
Example :
First contact at 1235, second contact at 1237 = 2 minutes between them. Distance measured between those two is 1000yds. Divide the Distance by the time means 1000yds by 2 minutes. Multiply the result with 60 (for 60 minutes = 1 hour). The last step is to divide that result by 2025 (because we are using yards for distance and 2025 yds are 1nm). The result would be 15(kts).
Just the numbers :
1000 / 2 = 500
500 * 60 = 30000
30000 / 2025 = 15
You can use whatever time lies between your two positions, just the example uses 2 minutes.