C13 Practical Navigation

Question 1

What are the two main types of departures you can do in VFR, referring to a nav log

Answer 1

Overhead Departure and En route departure

Question 2

What is an overhead departure?

Answer 2

A departure that involves you circling overhead the dep. aerodrome and using it as your first point on your nav log.

here, you aim to reach a desired altitude and speed above the dep. aerodrome before you fly towards your next checkpoint. Once you are set, and fly overhead your departure aerodrome, you fly the heading to your next checkpoint and start the timer

Question 3

What is an enroute departure?

Answer 3

The En route departure means that after take off you immediately fly the heading to your first checkpoint on your nav log, reaching your desired speed and altitude on the way.

Question 4

What is the 1 in 60 rule?

Answer 4

For every 60nm flown, one mile off track corresponds to one degree off track.

So, if you have flown for 60nm, flying 15 degrees North off track, you are 15 nm North of where you should be

Question 5

If you have travelled 15nm and you are one mile off track, using the 1 in 60 rule, what would be your track error after traveling 60nm?

Answer 5

4 degrees off track.

The 1 in 60 rule states that for every 60nm travelled and being one mile off track, you subtend an angle of 1 degree. As you have only travelled 15nm but are already 1 nm off track, you off track angle is 4 times greater

Question 6

What is the equation for track error (in degrees)?

Answer 6

60 x Distance Off track (nm)) / distance travelled along the track (nm)

Question 7

You realize you are off track and you are before the halfway point of your leg. How would you use the 1 in 60 rule to track a course that would take you straight back to your original track? (This is called the Double Track Error Method)

Answer 7

1. Find out how many degrees you are off track from your previous checkpoint.
2. If for example, you find you are 5 degree off track, simply fly 5 degrees towards your original track to fly parallel to it, and then another 5 to fly towards it

i.e. Change heading by twice your track error to fly a heading that will take you back to your original track

Question 8

You realize you are off track but are after the halfway point of your leg. You cannot use the Double track error method s this would make you miss your next checkpoint. So, how would you be able to reach your next checkpoint? (Hint: Use the track error formula)

Answer 8

1. Find the track error from your previous checkpoint
2. Find the track error to from your next checkpoint
3. Sum the two track error together and change heading by your total track error. This will take you directly to your next checkpoint

Question 9

After 40 miles you realize you are off track by 3nm. What is your track error?

Answer 9

Track error = 60 x distance off track (nm) / distance flown from previous checkpoint(nm)

Track error = 60 x (3/40) = 4.5 degrees

So you are 4.5 degrees off track from you previous checkpoint

Question 10

What is the Closing Angle Method?

Answer 10

It is another way to find your heading to your checkpoint when off track.

1. Find how far along your original course you are from your previous checkpoint as a fraction of the total leg (e.g. 1/4)
2. Invert this fraction and multiply it by the angle from your next checkpoint to your aircraft
3. This is how much angle correction to port or starboard you need to reach your next checkpoint

Question 11

After spotting your 3rd checkpoint you realize you are 2 miles to the left of your desired track, what would be the heading to steer to fly directly to your next checkpoint?

You know from your flight planning that the leg to your 3rd checkpoint is 49nm, and you are 33nm along it.

Answer 11

1. Find track error: Here we need the angle from the next checkpoint so:

60 x 2nm / (49-33) =7.5 degrees off track

2. Now, using the closing angle method:

You are more or less 2/3 of the way along your original track so invert the fraction and multiply it by your off track angle

3/2x7.5 =12 degrees

So, to fly directly to your checkpoint correct your heading by 12 degrees starboard (to the right)

Question 12

What are the 2 different ways of calculating track error?

Answer 12

1 in 60 rule

Formula for track error: 60 x distance off track / distance from last checkpoint

Question 13

If I am 5nm from my last checkpoint, and 3 nm off track, what is my track error using the 1 in 60 rule?

Answer 13

If we continued like this for another 55nm, when we are 60nm from the last checkpoint we would be 36nm off track (60/5x3)

The 1 in 60 rule says for 60nm every nm off track is 1 degree

So our track error from our last checkpoint is 36 degrees