An examination of the spectral class low frequency limit for helicopters

Details

• Creators:
  Schulz, Noah E. ; Boeker, Eric
• Corporate Creators:
  John A. Volpe National Transportation Systems Center (U.S.)
• Corporate Contributors:
  United States. Department of Transportation. Federal Aviation Administration. Office of Environment and Energy
• Subject/TRT Terms:
  • Helicopters
  • Aircraft noise
  • Sound level
  • Measurement of electromagnetic phenomena
  • Noise sources
  • Noise prediction
  • Noise model
  • Helicopter noise
  • Integrated Noise Model
  • Helicopter noise data
  More +
• Publication/ Report Number:
  DOT-VNTSC-FAA-14-03
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  John A. Volpe National Transportation Systems Center (U.S.)
• Abstract:
  Currently, INM and AEDT do not use spectral data below 50 Hz in their noise computations. However, helicopter rotor rotational noise is dominant below 50Hz, with a fundamental frequency at the blade-pass frequency (BPF) and harmonics at integer multiples of BPF. Noise data for several helicopters have been measured for inclusion in the INM/AEDT database with expanded spectral data down to 12.5 Hz. The purpose of this effort is to determine what effects, if any, inclusion of low frequency data will have on resulting noise modeling. The results of which would determine if and how an expanded-spectra capability should be included in AEDT.
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/12003/dot_12003_DS1.pdf
• File Type:
  [PDF - 1.13 MB]
• Collection(s):
  Volpe Center
• Main Document Checksum:
  urn:sha256:ed55635d044a911343b3881c54870c3e39532ab03ab38f10d98b177944439a15