U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PUBLICATIONS

NIST Special Publication 250-79 Airspeed Calibration Service.

Published

Author(s)

Tsyh Tyan Yeh, J. M. Hall

Abstract

The National Institute of Standards and Technology (NIST) provides calibration services for airspeed instrumentation such as Pitot-static tubes, anemometers (ultrasonic, thermal or hot-wire, cup, and propeller types) as well as others. The NIST calibration system consists of a wind tunnel and a Laser Doppler Anemometer (LDA). The standard for airspeed measurement is a fiber optic LDA, which is calibrated with known velocities produced by a rotating disk. A Pitot-static tube probe and thermal anemometer are used as check standards. The wind tunnel used for the calibration has a test cross section of 1.5 m by 2.1 m and water droplets injected into the wind tunnel from fine spray nozzles provide the light scattering particles necessary for the operation of the LDA. The range of the airspeed in the calibration service is from 0.15 m/s to 40 m/s.This document also describes the methods of operation and uncertainty of NIST airspeed standards. An extensive component analysis of the system was performed. Over the calibration range, the airspeed uncertainty is found to be a function of airspeed and the expanded uncertainty at 95 % confidence level, i.e. k = 2, in m/s can be expressed by the root-sum-square of 0.0064V and 0.0036 m/s, where V is airspeed in m/s. This gives a maximum uncertainty of 2.5 % (0.0038 m/s ) at the lowest airspeed of 0.15 m/s and a minimum uncertainty of 0.65 % (0.26 m/s ) at the highest speed of 40 m/s.
Citation
Special Publication (NIST SP) - 250-79
Report Number
250-79
NIST Pub Series
Special Publication (NIST SP)
Pub Type
NIST Pubs

Download Paper

https://doi.org/10.6028/NIST.SP.250-79

Keywords

airspeed calibration, airspeed standards, uncertainty analysis, windspeed
Optical physics and communications

Citation

, T. and Hall, J. (2007), NIST Special Publication 250-79 Airspeed Calibration Service., Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.SP.250-79 (Accessed April 25, 2024)

Created September 26, 2007, Updated November 10, 2018