SO1106 Embedded GPS/INS (EGI)

Question 1

What are some of the shortfalls of mechanical Gyros?

Answer 1

Wear and tear will cause precession errors.
Dirt and dust can enter the vacuum
High-G adversely impacts the rotation of the Gyro

Question 2

What is the drift rate of the RLG in the T-38C?

Answer 2

Less than 0.8NM/hr

Question 3

The three major segments in GPS

Answer 3

Space, User and Control

Question 4

How many satellites in the normal GPS operational constellation?

Answer 4

24 (and 3 spares)

Question 5

How many satellites are visible at all times from any point on earth?

Answer 5

5-8

Question 6

How many orbital planes are there for satellites?

Answer 6

6 (with nominally 4 satellites in each)

Question 7

What is the Precise Positioning System (PPS) accuracy?

Answer 7

22 m horizontally
27.7 m vertically
200 nanoseconds time

Question 8

What is the GPS hot start, time and accuracy?

Answer 8

18 seconds, 25 meters

Question 9

What is the GPS warm start, time and accuracy?

Answer 9

75 seconds, 25 meters

Question 10

How many seconds does the EGI require to power down?

Answer 10

10s

Question 11

How long does SH alignment take?

Answer 11

1.5 min or less

Question 12

How long does coarse alignment take?

Answer 12

2 minutes

Question 13

How long does fine alignment take?

Answer 13

4 minutes

Question 14

How long does normal GPS acquisition take in the T-38?

Answer 14

1.5-3 minutes

Question 15

What altitudes does the RALT indicate?

Answer 15

From 0’ to approximately 5200’

Question 16

What is the precision of the RALT?

Answer 16

+/-2’ or 2% whichever is highest when within +/- 45 degrees of straight and lvl.

Question 17

How much can the YSAS move the rudder?

Answer 17

+/-2 degrees (this is in addition to the +/-2 degrees of the rudder trim)