Download or read book Comparison of Speech Intelligibility in Cockpit Noise Using Sph 4 Flight Helmet with and Without Active Noise Reduction written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-11 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Noise Reduction (ANR) is a new technology which can reduce the level of aircraft cockpit noise that reaches the pilot's ear while simultaneously improving the signal to noise ratio for voice communications and other information bearing sound signals in the cockpit. A miniature, ear-cup mounted ANR system was tested to determine whether speech intelligibility is better for helicopter pilots using ANR compared to a control condition of ANR turned off. Two signal to noise ratios (S/N), representative of actual cockpit conditions, were used for the ratio of the speech to cockpit noise sound pressure levels. Speech intelligibility was significantly better with ANR compared to no ANR for both S/N conditions. Variability of speech intelligibility among pilots was also significantly less with ANR. When the stock helmet was used with ANR turned off, the average PB Word speech intelligibility score was below the Normally Acceptable level. In comparison, it was above that level with ANR on in both S/N levels. Chan, Jeffrey W. and Simpson, Carol A. Unspecified Center NAS2-12425; NAS2-13188; RTOP 505-61-51...

Download or read book Comparison of Speech Intelligibility in Cockpit Noise Using SPH 4 Flight Helmet with and Without Active Noise Reduction written by and published by . This book was released on 1990 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Noise Reduction (ANR) is a new technology which can reduce the level of aircraft cockpit noise that reaches the pilot's ear while simultaneously improving the signal-to-noise ratio for voice communications and other information-bearing sound signals in the cockpit. A miniature, ear-cup mounted ANR system, developed by Royal Aerospace Establishment, Farnborough, United Kingdom, was tested by U.S. Army Aeroflightdynamics Directorate, Simulation and Aircraft Systems Division, Crew Station Research and Development Branch to determine whether speech intelligibility is better for helicopter pilots using ANR compared to a control condition of ANR turned off. The ANR system was installed in a stock Army SPH-4 flight helmet, and tested in a background of recorded AH-1S (Cobra) cockpit noise, using phonetically balanced word lists, per MIL-STD-1472C. Two signal-to-noise ratios (S/N), representative of actual cockpit conditions, were used: 0 dB and +10 dB for the ratio of the speech to cockpit noise sound pressure levels. Speech intelligibility was significantly better with ANR compared to no ANR for both S/N conditions. Variability of speech intelligibility among pilots was also significantly less with ANR. When the stock helmet was used with ANR turned off, the average PB word speech intelligibility score was below the Normally Acceptable level, per MIl-STD-1472C in the 0 dB S/N levels and exceeded the Exceptionally High Intelligibility level with S/N +10 dB. Keywords: Cockpit communications, Active noise reduction.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1990 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances In Industrial Ergonomics And Safety V written by R Nielson and published by CRC Press. This book was released on 2003-09-02 with total page 1009 pages. Available in PDF, EPUB and Kindle. Book excerpt: Each year public awareness of the importance of ergonomics for improving people's working conditions and home environment increases, as the application of ergonomics brings more and more tangible benefits to society at large. The Annual International Industrial Ergonomics and Safety Conference held in Copenhagen, Denmark in June 1993, sponsored by the International Foundation for Industrial Ergonomics and Safety Research brought together more than 200 ergonomic professionals from North America, Europe and Asia to present over 120 research papers, in a quest to share their knowledge of new developments in design for people and improving safety at work.; This volume is a reference on the variety of problems that industrial and office workers face today, and moreover, offers solutions in the drive towards the safe workplace.

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1994 with total page 1064 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flight Research at Ames written by Paul F. Borchers and published by . This book was released on 1999 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA SP written by and published by . This book was released on 1962 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).

Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 1388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeronautical Engineering A Cumulative Index to a Continuing Bibliography supplement 261 written by and published by . This book was released on 1991 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Audio Effectiveness in Aviation written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Aerospace Medical Panel. Symposium and published by . This book was released on 1997 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Noise Environs and Helmet Performance for the P 1127 V STOL Aircraft written by Henry C Sommer and published by . This book was released on 1968 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the evaluation was (1) to measure the acoustic noise environment in the cockpit of the United Kingdom Hawker Siddeley P-1127 V/STOL aircraft that would serve as an acoustic guideline for cockpit noise levels of aircraft being contemplated or under construction, and (2) to determine the acoustic attenuation of various Air Force flight helmets in the inventory or being contemplated for Air Force inventory items. Cockpit sound pressure levels in the P-1127 V/STOL aircraft at various engine rpm settings were measured. The cockpit noise environment at maximum engine rpm was reproduced in the laboratory and used to obtain objective attenuation data for three Air Force flight helmet/liner configurations. Measurement of real-ear attenuation at threshold were also accomplished on the helmet/liner configurations. (Author).

Download or read book Cockpit Noise and Speech Interference Between Crewmembers written by and published by . This book was released on 1989 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Massed Versus Distributed Practice in Learned Improvement of Speech Intelligibility written by Jerry V. Tobias and published by . This book was released on 1976 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Manikin Measurements of the Noise Attenuation Provided by Flight Helmets written by John R. Forstall and published by . This book was released on 1968 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the noise attenuation provided by five flight helmets were obtained on a manikin head and compared with attenuation measurements obtained on human subjects according to the USASI Standard for Evaluating Real-Ear Attenuation at Threshold. The two sets of measurements were similar. The manikin method has certain advantages which should be considered in terms of the particular requirements of an evaluation program: (1) a helmet can be optimally fitted with little expenditure of time; (2) variability introduced by human factors is kept at a minimum; (3) high levels of noise can be used as the test stimulus; (4) visual and auditory monitoring of the attenuated noise provides the experimenter with a precise appraisal of the fit as adjustments are made; (5) manikin measurements are particularly useful in revealing improvements in attenuation resulting from minor modifications. (Author).