IDC Underwater Navigation & Dive Planning

Question 1

What are the two primary methods of underwater navigation taught in PADI training?

Accepted Answer

Natural navigation (using environmental features) and compass navigation (using a magnetic compass)

Answer

PADI teaches two primary navigation methods: natural navigation using underwater landmarks, current direction, and bottom contour; and compass navigation using a magnetic compass.

Question 2

How do you calculate the reciprocal heading on a compass when navigating in a straight line?

Accepted Answer

Add 180 degrees if the heading is below 180, or subtract 180 degrees if it is 180 or above

Answer

The reciprocal (return) heading is found by adding 180 degrees if the original heading is less than 180 degrees, or subtracting 180 degrees if it is 180 degrees or greater.

Question 3

What is a 'natural navigation check-in point' and how should divers use it?

Accepted Answer

A distinctive underwater landmark that divers identify to confirm their position during a dive

Answer

Natural check-in points are distinctive underwater landmarks (rock formations, coral heads, anchors) that divers identify during the dive to confirm their position and progress.

Question 4

What key elements should a dive plan include?

Accepted Answer

Maximum depth, dive duration, air turnaround pressure, buddy assignments, entry/exit procedures, signals, and emergency contacts

Answer

A dive plan is a comprehensive pre-dive planning document covering all safety-critical parameters: depth, time, air management, buddy system, site-specific procedures, and emergency response.

Question 5

What does the 'rule of thirds' refer to in dive air management?

Accepted Answer

Using one-third of the air supply for the outbound journey, one-third for the return, and keeping one-third in reserve

Answer

The rule of thirds is an air management principle: use one-third going in, one-third for the return, and keep one-third as an emergency reserve.

IDC - Certified Instructor Development Course Trainer Practice Test

IDC - Certified Instructor Development Course Trainer Practice Test

IDC Underwater Navigation & Dive Planning