Fiber-Optic Gyros - Northrop Grumman Electronic Systems ...

Latitude (deg)
24235
33.05
33
32.95
32.9
32.85
32.8
32.75
32.7
32.65
Figure 13. LN-260 INS/GPS
F16[1] C015.1539.00015.BNG016.bd01.mat
32.6
32.55
-99 -98.8 -98.6 -98.4 -98.2 -98 -97.8 -97.6 -97.4
Longitude (deg)
COMMERCIAL PRODUCTS
8
Figure 14. Synthetic Aperture Radar Image of
Fort McHenry Obtained Using the LN-260 to
Stabilize and Navigate the SAR Antenna
Figure 15. LN-260 Flight Test Trajectory (left) on an F-16 and
Radial Position Error Rate Versus Time (right)
The LTN-101E (Figure 16) uses fiber-optic gyros
in a four MCU package for use on commercial
transport aircraft. The LTN-101E also uses navigation
grade silicon MEMS accelerometers. It performs both
a navigation function and an air data function and
integrates with an external GPS receiver.
The graph on the left of Figure 17 shows the free
inertial position error during a 15 hour static
laboratory navigation test. The green line indicates the
two nautical mile per hour (nmph) performance
requirement and the red line is the radial position error
rate (1.69 nmph) for the first hour of testing. The
graph on the right in Figure 17 shows the free inertial
position error for a flight test that lasts over 10 hours.
The LTN-101E readily meets its free inertial
performance requirements.
The LTN-101E is in development and
qualification and will start production in 2007. It will
be DO-178 certified.
Another fiber-optic gyro product for commercial
transport aircraft is the LTR-97. This a replacement for
an old mechanical direction gyro/vertical gyro
(DG/VG) system used on older transport aircraft. It
provides synchro outputs for pitch, roll, and heading,
analog outputs for pitch and roll, and discrete outputs.
It is DO-178A certified. Over 300 systems have been
delivered to date and production is ongoing.