IN-FLIGHT MEASUREMENT OF ROTOR BLADE AIRLOADS, BENDING MOMENTS, AND MOTIONS, TOGETHER WITH ROTOR SHAFT LOADS AND FUSELAGE VIBRATION, ON A TANDEM ROTOR HELICOPTER. VOLUME 3. DATA PROCESSING AND ANALYSIS SYSTEM
Abstract
An extensively instrumented tandem rotor helicopter was flight-tested to measure the rotor blade airloads and the resulting rotor blade motions and bending moments, rotor shaft loads and moments, and fuselage vibration. The voluminous output of this extensive instrumentation was processed by a fully automated data system which is described in the volume. Data were tape-recorded in sequenced-multiplexed, frequency-modulated (FM) form during flight testing. The FM signals were discriminated to analog form and were digitized by using a high-speed analog-to-digital converter. Digital data were calibrated, corrected for temperature and load interactions, and harmonically analyzed by using a series of digital computer programs. Airloads pressure data were numerically integrated to determine instantaneous blade section lift and pitching moment and the lift and pitching moment of the entire rotor blade. Data were also prepared for other analyses. The data system also included various data checks which are discussed. Substantiating tests and analyses that were performed to ensure the proper operation of this system are also presented. Data output from this program is available on a computer tape (nine-track, IBM System 360) in fully identified form for utilization in further analyses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1967
- Accession Number
- AD0671662
Entities
People
- John W. Obbard
Organizations
- Boeing Rotorcraft Systems