Unplanned Diversions

Question 1

An an aviation chart, what is the radius in NM of a MATZ

Answer 1

5nm

This is useful to know as you can measure your thumb against the MATZ to estimate range on an aviation chart using your thumb (rule of thumb!)

Question 2

What is the typical rule of thumb for general aviation speeds per minute for;
60kts
90kts
120kts

Answer 2

1. 60kts = 1nm per minute
2. 90kts = 1.5nm per minute
3. 120kts = 2nm per minute

Question 3

What is the “easy” angle to use for time calculations around a diversion

Answer 3

60॰

Question 4

When planning for a diversion, in order to help navigation and estimating distances and times, what should a pilot plan for when choosing a turn point on the aviation chart

For example, if I were flying to Gloucester and was then told to divert to Wellesbourne, what should I do before just turning the plane towards Wellesbourne

Answer 4

Plot diversion from a key landmark

Plan diversion from key landmark so you can identify when above it
Remember: TIME TURN TALK
Mark the time you start your diversion from the planned landmark
You can now work out your ETA to the destination from the landmark

Question 5

Once you have started a diversion, what critical piece of information should you check on your aviation chart and compare to your planning

Answer 5

Minimum Safe Altitude
(MSA)

Check the MEF - Minimum Elevation Figure - for the section you are flying and ensure you have sufficient clearance

Question 6

What is the formular to calculate the maximum wind correction angle (WCA॰)

Answer 6

Max MCA॰ = ( 60 / TAS ) x wind speed

Example, if TAS = 90 kts, and wind is 090॰ @ 20kts and our track is 360॰
60 / 90 = 0.666
0.666 x 20 = 13॰

Question 7

Using the rule of thumb DI method, you are flying a track 360॰, with a wind component of 045॰ @ 20kts. Calculating the max WCA॰, what is the correction required.

HINT: Draw a circle to reflect the DI instrument and plot the lines

Answer 7

9॰

1. If TAS = 90 kts, and wind is 090॰ (full cross wind component from 360॰) @ 20kts and our track is 360॰
   60 / 90 TAS = 0.666
   0.666 x 20 = 13॰
2. We know our wind is actually from 045॰. On the DI imagine the lines that represents the 090॰ cross wind component, and a line from the actual wind direction to the center of the DI
3. Imagine drawing a line down from the wind component (i.e. 045॰) down to the max cross wind line.
4. Note the line intercepts the max cross wind component at around 70% of the way. This means we need 70% of the WCA॰
5. 70% of 13॰ = 9॰
   LINK HERE