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From page 42... ... 42 The entries in the following bibliography are not intended to be comprehensive, but rather to summarize interpretations of findings of some of the better known studies of the annoyance of helicopter noise. They exclude studies intended mostly to measure helicopter noise emissions and some laboratory studies of rotor noise whose findings have little direct bearing on the design of social surveys of the annoyance of helicopter noise. Read the entire page →
From page 43... ... 43 an overhead aircraft might crash. The attitudinal response of bother or annoyance to aircraft noise was found to be positively correlated with crash fear: "On the whole, residents who feared a crash were more annoyed by aircraft noise than those who did not." The authors noted that the scatter of dose-response points about their trend line exhibited greater scatter than expected by chance alone. Read the entire page →
From page 44... ... 44 report also cites two studies of "heightened reaction" to helicopter noise -- presumably not associated with blade slap -- by Schomer (1983) and Atkins et al. Read the entire page →
From page 45... ... 45 Through the assistance of the Volpe Center, FAA then acquired measurements of helicopter noise at the urban center of New York City, chosen in order to quantify the noise levels in a densely populated metropolitan community. Among the locations of focus were the New Jersey Liberty State Park and the vicinity of downtown heliports. Read the entire page →
From page 46... ... 46 FAA grouped the approaches for addressing the noise issue that were gathered from all stakeholders into 10 groups and the report presents technical discussions relative to each approach: • Ensure Safety of Helicopter Operations • Establish Noise Abatement Helicopter Routes • Keep Helicopters at Higher Altitudes • Limit Hovering • Reduce Helicopter Source Noise • Reduce Flights by Electronic News Gathering (ENG) Operations • Restrict Helicopter Flights • Charge Fees for Helicopter Operations • Improve Information on Helicopter Operations and Noise Abatement Practices • Establish a Forum for Addressing Helicopter Noise Issues. Read the entire page →
From page 47... ... 47 routes in the vicinity of specific airports illustrates the problem of separating helicopters from fixed-wing aircraft. Specific areas of concerns such as the Hollywood Bowl and Getty Center, as well as communities where helicopters are an issue are described. Read the entire page →
From page 48... ... 48 and single impulse. The positive slope of about 1.5 dB per doubling of repetition rate (or 5 dB/decade) Read the entire page →
From page 49... ... 49 It is interesting to note that the guidelines generally recommend that helicopters stay 1,000 ft above noise-sensitive areas. The following aircraft are included in the noise abatement procedures document and, while it appears comprehensive, it is from 2009 and should be updated as some of the guidance for some of the aircraft listed is quite general and not as aircraft-specific as that done for other aircraft in the list: Agusta A109A, A109A II, and A109C Bell Helicopter 204, 205, 212, UH-1, AH-1 Series Helicopters 206A, 206B, 206B-3, 206L, 206L-1, 206L-3, 206L-4, and 206LT 427, 429 407 430 Boeing 234 and CH-47A [Note: Some information also applies to 107 and CH-46.] Read the entire page →
From page 50... ... 50 two sets of factors other than the conventionally measured, A-weighted, acoustic energy of helicopter noise emissions. The first component of virtual noise is the noticeability of distinctive features of helicopter noise emissions, such as high-speed impulsive noise (HSI) Read the entire page →
From page 51... ... 51 Miller, N., "Technical Memorandum, Review of Studies that Address Effects of Helicopter Noise," HMMH, Feb. 2015 (for the Town of East Hampton) Read the entire page →
From page 52... ... 52 example, Molino notes "The presence of blade slap, in and of itself recognized as contributing to increased annoyance, produces changes in other acoustic parameters that can compensate for or account for the increased annoyance cause by the presence of blade slap." Molino concludes from the contradictory and inconclusive nature of the findings of laboratory studies about the annoyance of helicopter noise that "there is apparently no need to measure helicopter noise any differently from other aircraft noise." The logic and universality of Molino's conclusion are open to question, given the limited nature of comparisons that Molino describes among the findings of different forms of laboratory studies of the annoyance of helicopter noise. Another major limitation of Molino's review is that he confines his review to the direct annoyance of airborne acoustic energy produced by helicopters, and ignores the potential contributions to annoyance of secondary emissions (audible rattle and sensible vibration) Read the entire page →
From page 53... ... 53 their annoyance because they do not take into consideration the temporal context of noise intrusions.ii They propose instead a method of continuous judgment, such that the annoyance of helicopter and other ". Read the entire page →
From page 54... ... 54 Pater, L., R Yousefi, and J Read the entire page →
From page 55... ... 55 and temporal considerations, are shown in Figure B3. This figure plots the correlations in four groups of differing temporal considerations. Read the entire page →
From page 56... ... 56 noise] related to impulsiveness is perceivable by subjects but is not accounted for by either EPNL or [ISO's] Read the entire page →
From page 57... ... 57 (repetition) rates, to the annoyance of a single broadband noise. Read the entire page →
From page 58... ... 58 fire, and quarry blasting) , and treats helicopter blade slap as a special case. Read the entire page →
From page 59... ... 59 Brentner, K., "Rotor Source Noise Prediction and the Challenges of Rotor Noise Abatement," Pennsylvania State University, 2014 [Online] Read the entire page →

From page 42...

... 42 The entries in the following bibliography are not intended to be comprehensive, but rather to summarize interpretations of findings of some of the better known studies of the annoyance of helicopter noise. They exclude studies intended mostly to measure helicopter noise emissions and some laboratory studies of rotor noise whose findings have little direct bearing on the design of social surveys of the annoyance of helicopter noise.