Summary - P-8020068

CHAPTER THREE

INSTRUMENTS FLIGHT PLANNING

Your action is:

Plot 235o/65 kts on windface.

Set new course of 139o on TC mark.

Note a RCW = 65 kts and TW = 7 kts.

Based on a guide = number of 5; 65/5 = 13 right crab.

Turn to 152o (139o + 13o R) at 0908.

Estimate GS = 307 kts.

Therefore, ETA to AMG = 0926.

Once the wind (235/65) is determined it is immediately applied to the next leg in order to make

an appropriate turn (152o). To continue, an ETA is predicted (0926) based on a wind derived

GS.

Once again, we are applying DR principles. We use the best wind information available and

predict what happens on the subsequent leg. Use of the CR-2 is encouraged to increase

accuracy.

Theoretically, the entire route could be flown in this manner. Of course, winds do change and

so, over a long flight, accuracy is degraded. By applying fundamental DR principles such as

speed, time, distance, and wind, we can predict with reasonable accuracy our position and the

time of arrival.

305.

SUMMARY

Do not assume DR is strictly used as a last resort when everything else has gone wrong. You, as

the NFO, should be able to predict where the aircraft is at a certain time (ETAs) and constantly

update the wind. If you are on a leg that is too short to do an accurate GS check, as long as you

have updated wind information, you can use it to predict a GS.

3-6 SITUATIONAL AWARENESS