Navigation

Question 1

The L and R IRU provide inputs corresponding to the Captains and FO instruments. What about the RDMI?

Answer 1

The RDMI recieves IRU info from the opposite.

Question 2

What are the 4 positions of the Nav switches and what do they mean?

Answer 2

OFF- alignment lost, 30 second shutdown as the shutdown sequence
commences.
ALIGN - Initiates alignment when parked
NAV - Normal operating mode, permits system to enter NAV mode after completing alignment, initiates a 10 min alignment if selected OFF.
ATT- Provides only att and heading info.

Question 3

The IRS mode sel presents HDG information in True north?

Answer 3

Yes

Question 4

What does flashing align mean?

Answer 4

Irregularity of the alignment process.

Question 5

How do you accomplish an IRS full alignment?

Answer 5

• Airplane must be parked
• Requres approx. 10 min
• Align lights should be extinguished

Question 6

Is it normal for ON DC light to illuminate on IRS mode selector?

Answer 6

Yes but only during start when performing backup power test.

Question 7

What does it mean if the fault light is illuminated on IRS?

Answer 7

INOP remainder of flight and ATT/NAV modes have a fault.

Question 8

If the GPS fails what else does the a/c have to calculate position?

Answer 8

• DME-DME
• VOR-DME
• Localizer stations with DME
• IRS

Question 9

Describe ANP..

Answer 9

Actual Navigation Performance - Estimates the quality of position in NM, it is limited to potential errors. The smaller the number the better!

Question 10

Describe RNP…

Answer 10

Required Navigation Performance - what is needed to fly the segment or during a certain operation.

Question 11

Where is RNP and ANP displayed?

Answer 11

FMS POSITION REF pg 2/4

Question 12

Whats the difference in the 757 and -300/767-300ER variant when operating in stby power with respect to the IRUs

Answer 12

757 - the left IRU is limited to 5 min of power.

-300/767-300ER - the right IRU is limited to 5 min of power

Question 13

The -300 has ADIRUs. What is that?

Answer 13

Combination of both ADC and IRU

Question 14

How many ADFs o 757 vs 767?

Answer 14

1 on 757 and 2 on 767. Can be parked by selecting 100.0

Question 15

What is the least likely to show RADAR returns…

Answer 15

Small ice crystals

Question 16

Whats the maximum display range for weather and turb?

Answer 16

320 for wx and 40nm for turb

Question 17

What bus is the radar connected to?

Answer 17

L AC bus

Question 18

What position should the -300 weather radar remain in during ground ops?

Answer 18

Test position

Question 19

Does the 757-200 have predictive WS?

Answer 19

No, 757-300 does. Available about 12 secs after RADAR scan begins.

Question 20

When does the RADAR automatically scan for windshear?

Answer 20

• Thrust levers are advanced for TO
• A/c is in flight below 2,300 ft RA
• Predictive ws alerts are only issued when the aircraft is below 1,200 RA.

Question 21

When does predictive ws change from a caution to a warning message?

Answer 21

3nm its a caution

1.5nm its a warning