In a recent letter regarding the noise from the Navy’s EA-18G Growler aircraft at Naval Air Station Whidbey, author Terry Sparks begins by proclaiming: “As an engineer I keep an open mind when reading studies” (“Noise from Navy Growlers on Whidbey no threat to health”). An “open mind” did not seem evident in the wide-ranging, often fallacious, and scientifically unsupported statements in the discourse that followed.
For example, he claimed, “that a 150-decibel jet engine noise level will drop to 81.6 decibels a half-mile away and down to only 75.5 decibels a mile away. The noise threshold is 70 decibels.” Both claims are wrong.
Actually the noise attenuation rate depends entirely on the jet’s altitude and power setting: A jet at 5,000 feet and 84.5 percent power will be 87 decibels (dB) on the ground below and 81 dB one mile away, or at 10,000 feet, it will be 77 dB on the ground and 75 dB at one mile away (Table 3.1.2 in the Navy’s environmental impact statement).
Also questionable is his claim that the “noise threshold is 70 decibels.” Presumably, he is referring to the old Shultz curve annoyance threshold, which though proven to be wrong, was 65 not 70 dB; however, it no longer stands. Worldwide acoustic scientists now fully agree the annoyance threshold is around 50 db. Note that 70 db is four times louder than 50 dB.
Then he goes on to disparage an underwater noise study saying “it twisted the facts.” As an engineer, he should understand that publishing in the formal scientific literature requires critical peer review to validate the efficacy and credibility of the research. That process ensures nothing is twisted. Reviewers, if even suspected of having a bias or personal agenda, are excluded from the pool of candidates.
He also argues that the Growlers are essential in protecting the U.S. from China, yet a recent article in National Defense Magazine states that Growlers “have inherent limitations that may be prompting calls for divestment.” See “Questions emerge after Congress prohibits Growler divestment” in nationaldefensemagazine.org.
That article goes on to explain that “[Growlers] are not able to reliably standoff jam overlapping air defense radars that can reach out to 250 nautical miles. Yes, the Growlers have a unique combination of capabilities and the ability to do RF-enabled cyber … but against China, it is going to be difficult to conduct, given their air defense and sensor networks.”
If the author really has an open mind, he will be open to what Hudson Institute Senior Fellow Bryan Clark suggests; that is, the Navy should “shuffle its master aviation plan to put the best, lowest-time Growlers into its carrier air wings while retiring the rest or sending them to reserve expeditionary [land-based] squadrons.”
That would go a long way toward fixing the noise issue and it seems a lot wiser than his suggestion of buying out all of Coupeville via eminent domain.