F-35
One of four F-35 fighter jets parked at the Vermont Air National Guard base at the Burlington International Airport in South Burlington on Wednesday, May 29, 2019. Photo by Glenn Russell/VTDigger

In the eyes of many who oppose the F-35, the Vermont Air National Guard’s original sin came during the era of the F-16, when pilots began frequently implementing afterburners, which are essentially auxiliary jets that increase thrust — and noise  — on takeoff. 

There was no environmental impact statement or in-depth public debate about the use of afterburners for the F-16, and some residents felt the military had snookered them. 

So when the prospect of the F-35s coming to the Burlington International Airport was raised, community members quickly raised the question of how often this new fleet would take off with afterburners. 

Documents obtained by VTDigger reveal that the Air Force is internally predicting that, at other bases hosting the F-35, afterburners might be used as much as 10 times more frequently than they originally publicly predicted. The Vermont National Guard, however, says that they still plan to use the boosters in a limited way.

A local activist plans to challenge that claim in court.

Originally, the Vermont Air National Guard and the Pentagon estimated that the F-35s coming to Vermont starting this fall would rarely use afterburners. In their detailed 2013 Environmental Impact Statement (EIS), the military estimated that the planes would use afterburners for roughly 5% of flight operations. This estimate not only influenced the contours of the resulting noise maps, but also the overall decision of whether Vermont was a good fit for the planes. 

Across the country, as other communities have been considered to base the planes, the military has plugged in similar afterburner predictions. Yet according to an internal Pentagon document obtained by VTDigger, real afterburner use on the F-35 may be much higher than publicly predicted.

As the Air Force moves forward with environmental impact reviews at other bases, it appears to be counseling officials to calculate afterburner use for at least 50% of all flight operations. The Air Force has already delayed at least one base review by at least four months “due to some discrepancies and concerns over F-35 flight elevation and afterburner usage.” 

“It’s all just a big Charlie Foxtrot,” one official involved in this review wrote to colleague in an email, using military slang for a messy situation. This official added that the chaotic situation “could have been addressed over a year ago when we all questioned the validity of only using 5% [afterburner].” He added that this new need to calculate higher afterburner use for the F-35 will “delay or at least complicate” environmental reviews for the plane going forward. 

If afterburners are employed on the F-35, decibels will skyrocket, increasing the risk of hearing damage for community members and likely widening and elongating the noise zone. According to a Pentagon source, who asked not to be named for fear of retribution, afterburner use at at least three Air Force bases with the F-35 — Hill in Utah, Eglin in Florida, and Luke in Arizona — has been higher than anticipated. 

An Air Force spokeswoman referred questions to the Vermont National Guard. In an e-mail, Guard Captain Mikel Arvovitch didn’t address VTDigger’s specific questions over whether Vermont officials had discussed increased afterburner use with federal officials, but said “nothing has changed.” 

“We will take-off in military power 95 percent of the time and afterburner five percent of the time,” Arcovitch wrote. 

In reaction to the document, Retired Col. Rosanne Greco of South Burlington, who has been leading the fight against the planes for years, was expected to file a legal request Thursday morning in federal court demanding the Air Force complete a supplemental impact study that would more accurately project F-35 afterburner use. Greco also requested the Air Force delay the plane’s basing, scheduled to begin any day now, until such an assessment is undertaken. 

Retired Col. Rosanne Greco
Retired Col. Rosenne Greco appeared before a joint meeting of the House General, Housing and Military Affairs Committee and the Senate Government Operations Committee at the Statehouse in Montpelier on Tuesday, Feb. 5, 2019. File photo by Glenn Russell/VTDigger

“Those of us who were working this years ago predicted that the F-35 would eventually be forced to take off in afterburner much of the time, especially in Burlington, which has a very short runway,” Greco told VTDigger. “The facts here are not surprising. What is surprising is it sure seems like we were lied to during the basing process.”

As VTDigger has previously reported, the original impact statement process was highly flawed, and saw political interference from Sen. Patrick Leahy’s office. 

Documents show that during this process, both Leahy’s office and Air Guard officials aggressively pushed the Air Force to alter noise modeling software in an apparent attempt to reduce the projected scope of noise pollution in the communities surrounding the airport. The Guard and Leahy’s office consulted with the plane’s manufacturer, Lockheed Martin, on the noise modeling.

[Read VTDigger’s 2018 series on the Burlington F-35 basing.]

The shift from one modeling software – Karnes 2 — to new software – Karnes 3 – was in direct conflict with orders from the Air Force’s national headquarters. In emails, Lynn Engelman, an Air Force noise/encroachment manager, complained that Vermont Guard officials had “hijacked” the environmental scoping process and were providing “inconsistent answers.”

A Pentagon official who was involved in the entire basing process said Vermont Air Guard officials became concerned when initial Karnes 2 estimates showed significant noise pollution around the airport. He said there was a concerted push by the Air Guard to adopt the newer Karnes 3 profile and tweak inputs to reduce noise estimates. 

“Burlington’s operational folks wanted to be in the analysis room every step of the way,” the official said. “They were changing the data and they wanted to see draft data before it got too far along. If they saw that a certain flight operation with a certain thrust level and angle was going to increase noise they would say ‘Oh, we won’t fly that way, we’ll do it this way, which will produce less noise.’”

Air Force Col. Lowell Nelson appeared to be nervous about using the Karnes 3 model for noise assessments in the Burlington area.

F-16 fighter jet
The last four Vermont Air National Guard F-16 fighter jets left the VTANG airbase during a “Viper Out” ceremony in South Burlington on Saturday, April 6, 2019. The F-16s arrived in 1986 and are being re-assigned elsewhere to make room for new F-35 jets at the base. Photo by Glenn Russell/VTDigger

“The potential concern is using this potentially unreliable area of data could significantly understate the noise contours,” Nelson wrote in a 2011 email to a colleague. “It would look ‘better,’ but maybe not appropriately so.”

Nelson also made the overriding point that truly accurate noise data would not be available until the planes touched down in Vermont. Indeed, there are many factors that can influence noise, including atmospheric conditions. 

In a 2010 email, Vermont Air Guard Lt. Col. Christopher “Pooter” Caputo said that if the Guard was able to secure use of Karnes 3 for the environmental assessment, “I’m confident [noise] numbers will decrease even more. My guess is they would probably be cut in half again if not even more! This just strengthens our argument that much more.”

Air Guard officials and Leahy’s office strong-armed Air Force officials who eventually complied. They subsequently delayed the release of draft environmental data and adopted the Karnes 3 model, according to government emails and documents.

In 2013, Caputo wrote it was not in the best interest of the Vermont Air National Guard to release updated noise projections to the public before the official statement naming Burlington a base for the planes.

“It will only add to the confusion of the ignorant SOBs that are fighting the F-35 beddown,” Caputo wrote to five fellow Air Guard officials.

Twitter: @Jasper_Craven. Jasper Craven is a freelance reporter for VTDigger. A Vermont native, he first discovered his love for journalism at the Caledonian Record. He double-majored in print journalism...

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