Accession Number:

AD0750607

Title:

A Suggested Method for Estimating Patch Length from Turbulence Measurements Using Results from Low Altitude Flights by a T-33 Aircraft.

Descriptive Note:

Aeronautical rept.,

Corporate Author:

NATIONAL AERONAUTICAL ESTABLISHMENT OTTAWA (ONTARIO)

Personal Author(s):

• Gould,D. G.
• MacPherson,J. I.

Report Date:

1972-08-01

Pagination or Media Count:

25.0

Abstract:

When an aircraft encounters a patch of turbulence, the RMS turbulence intensity is usually constant only over a portion of the total period of exposure. A method is suggested for estimating the patch length as a function of intensity for turbulence encounters that have two or more regions of different turbulence intensities. It makes use of the fact that the amplitude or level crossing distributions that fall between the normal distribution and the exponential distribution be closely approximated by a superposition of normal distributions of different intensities. Level corssing distributions of vertical acceleration from a series of T-33 low altitude turbulence research flights are analyzed using this procedure, and results from flatland and hilly lakeland are compared. Author

Descriptors:

• *TURBULENCE
• MATHEMATICAL PREDICTION
• INTENSITY
• JET TRAINING AIRCRAFT
• LOW ALTITUDE
• FUNCTIONAL ANALYSIS
• MEASUREMENT
• CANADA

Subject Categories:

• Aerodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE