ROTI

USE OF ROTI (RATE OF TURN INDICATOR)
1.THE RATE OF TURN INDICATOR IS EQUIPMENT WHICH INDICATES THE INSTANTANEOUS RATE AT WHICH THE SHIP IS TURNING.
2. THIS INDICATOR IS FED 60 TO 200 PULSES PER MINUTE FROM THE STEERING REPEATER AND FROM THIS INPUT IT WORKS OUT THE INSTANTANEOUS RATE OF TURN.
3. THE DIAL IS MARKED USUALLY 0 DEG. TO 60 DEG. ON EITHER SIDE. AS PER IMO PERFORMANCE STANDARD THE DIAL SHOUD BE MARKED NOT LESS THAN 0 DEG. TO 30 DEG. PER MINUTE ON EITHER SIDE AND GRADUATED IN INTERVALS OF 1 DEG. PER MINUTE.
4. AS WE KNOW THAT WHEN SHIP TURN SHE ACTUALLY TRAVERSES SOME DISTANCE ROUND THE ARC OF A CIRCLE AND CANNOT EXECUTE A SHARP TURNS ABOUT A POINT.
5. WHEN SHIP IS MAKING A TURN IT PRECISE THE SHIP TRACK UNCERTAIN DUE TO HER CHARACTERISTIC, CONDITION, WEIGHT AND UKC. 
6. THEREFORE NAVIGATOR USES THE TOUCH OF SHIP TRACK DURING THE TURN THAT IS UNCERTAIN OF POSITION UNTIL THE SHIP IS STEADED ON THE NEW COURSE.
7. IMO RECOMENDS FOR PASSAGE PLANNING IS NOT ONLY MONITOR THE POSITION ON STRAIGHT COURSE BUT ALSO ON CURVE SECTION OF PASSAGE. THIS CAN BE ACHIEVED BY THE TECHNIQUE CALLED RADIUS TURN BY THE HELP OF ROTI AND SHIP’S LOG.
8. THE RATE OF TURN IS BASED ON THE FORMULA ROT= V/R.
WHERE

V-> IS THE SPEED OF VSL OVERGROUND.
R-> IS RADIUS OF TURN.