NCAR Airborne Instrumentation Inventory

1. INSTRUMENT IDENTIFICATION

Instrument Designation:
Honeywell Laseref SM Inertial Reference System

Instrument Abbreviation:
ALAT, ALON, ALT, VEW, VNS, VSPD, PITCH, ROLL, THDG

Instrument Measurements:

a) Trace Gas


b) Cloud Physics/Aerosol


c) Radiation/Optical/Electrical


d) Additional Capabilities
Aircraft 3-dimensional position
Aircraft 3-dimensional ground speed
Aircraft 3-dimensional attitude

Resource Person/Developer:
Name: Dick Friesen
Affiliation: NCAR/ATD/RAF
Phone: (303) 497-1047
Email: rbf@ucar.edu

Principle of Measurement:
Data from laser gyros and strapped-down accelerometers are integrated by the Laseref's internal computer to produce all the measurements:

• Pitch angle
• Roll angle
• Yaw angle (true heading)
• Ground speed east and north components
• Vertical airplane speed (with damped input from external barometric pressure sensor
• Latitude
• Longitude
• Altitude (with input from external barometric pressure sensor)

In situ/Remote/Flux Measurement:
In situ

2. INSTRUMENT APPLICATION

Scientific questions to be answered:
Where am I?

Field projects in which the instrument has been used:
most

Publications describing the instrument, applications and field project results:

3. Instrument Deployment

Altitude:
all

Aircraft Platform:
all

Inlet Configuration/Location:


Calibration/Cross Calibration:


Operator Requirements:
15 minute (or more) alignment before use

Data Collection:
external

Post-flight Data Validation, Processing, Hours per Flight Hour etc.
RAF NIMBUS software processor
Post-project validation by RAF Project Manager

Physical Characteristics:
Dimensions:
Weight:
Power:
Other:

4. Instrument Performance

Linear Range:
± 90 deg (latitude, pitch)
± 180 deg (longitude, roll)
0 to 360 deg (true heading)
± 400 m/s (horizontal ground speeds)
± 200 m/s (vertical speed)

Response Time:
20 ms to 200 ms (5 to 50 samples per second depending upon measurement)

Detection Limits:
0.00017 deg (latitude, longitude, pitch, roll, true heading)
0.0020 m/s (horizontal ground speeds)
0.0095 m/s (vertical speed)

Accuracy:
± 0.027 deg per hour (latitude, longitude)
± 0.7 m/s per hour (horizontal ground speeds)
± 0.0254 m/s per hour (vertical speed)
± 0.033 deg per hour (true heading)
± 0.083 deg per hour (pitch, roll)

Precision:


Limitations (such as altitude, airspeed, etc.)

5. Alternative Techniques

6.Status/Plans

7.Comments