2016 PC Guide - Descent

Question 1

Turbulent Air Penetration

What are the turbulent air penetration speeds above 15,000 ft MSL?

Answer 1

NG - 280 kt / 0.76 Mach

CL - 280 kt / 0.73 Mach

Question 2

VNAV Descent

You are flying on a VNAV path descent, but did not program the Descent Forecast Page. Passing FL180, you set the local altimeter setting of 30.45. What will most likely occur to the VNAV mode at that point?

Answer 2

With a local altimeter of 30.45 set, the aircraft will now be about 500 feet high on the path. VNAV will revert to VNAV SPD.

Question 3

VNAV Descent

During a VNAV Idle Path Descent, does the FMC attempt to maintain target speed? If not, how can you “help” the aircraft stay at target speed?

Answer 3

The FMC does not attempt to maintain target speed during an Idle Path Descent. If necessary, you will use the thrust levers or the speed brake to stay at the target speed.

Question 4

VNAV Descent

During a VNAV PATH descent, you get a DRAG REQUIRED message. What does this mean? Should you deploy speed brakes?

Answer 4

This messages means that your airspeeds is more than 10 kts above the planned target speed. You may or may not need to deploy speed brakes depending on the speed restrictions.

Question 5

VNAV Descent

If you get high, what means do you have to get back on the PATH?

Answer 5

• Deploy speed brakes
• Increase the descent speed in the FMC
• Increase the descent speed using Speed Intervention
• Use vertical speed

Question 6

ILS Approach MCP Modes

You have been cleared for an ILS approach. When is it appropriate to select the MCP Approach Mode and why?

Answer 6

VOR/LOC or LNAV should be used to intercept the localizer course. After VOR/LOC capture, select the Approach Mode. If Approach Mode selected prior to approach capture, the aircraft could descend on the glide slope regardless of course guidance.

Question 7

Missed Approach Criteria

During an ILS approach, when must crews execute a missed approach.

Answer 7

• The CDI exceeds a 2 dot deflection while on the final approach segment in IMC.
• A 2 dot low glide slope deflection on the final approach segment in the IMC.
• In the NG, the expanded LOC pointer becomes “unfilled” while on the final approach segment in IMC.
• Either pilot directs a go-around