Operational Status:
- , not on request list but could be available if requested
General Description:
- Schematic for LAMS:
- The LAMS measures airspeed in a region of undisturbed airflow via the Doppler shift in the frequency of laser light returned from a laser beam focused ahead of the aircraft. The coaxial laser system uses optical heterodyning to detect the Doppler shift in light backscattered from atmospheric aerosols. The system uses fiber-based components and a laser producing 4W at a wavelength of 1.56 μm. The beam is focused about 12 m ahead of the aircraft and is capable of producing high-rate data (up to about 100 Hz). Because the system relies on backscatter from atmospheric aerosols, its performance is sometimes limited when aerosol concentrations are low, but it has performed in tests up to 90% of the time at flight altitudes exceeding 40,000 ft. For details of the test results, see the publication by Spuler et al. (2011) referenced in the "Documentation" section at the end of this page.
Measurement Characteristics:
- Overall estimate of uncertainty: 0.1 m/s
- Response time: 0.02 s
- Precision: 0.1 m/s
- Other measurement characteristics (comments on signal/noise, bias limits, etc): sometimes limited by low aerosol backscatter