The FAA issued a final rule today that prohibits jets with an mtow of 75,000 pounds or less from operating in the contiguous U.S. after Dec. 31, 2015, unless they meet Stage 3 noise levels. To take effect on September 3, the rule could affect up to 599 civil jets, though any of these aircraft that are hushkitted or otherwise modified to meet Stage 3 standards will be permitted to operate in the U.S. in 2016 and beyond.
Some models of the banned airplanes can be modified to meet Stage 3 noise levels with the installation of a hushkit, the FAA noted. “Of the 17 models of airplanes affected by this ban, hushkits had previously been available for six models: the Dassault Falcon 20; Learjet 23, 24 and 25; and the Gulfstream II and III. An unknown number of these airplanes may already have a hushkit installed.”
However, the only hushkits currently available for the affected Stage 2 jets are for the Gulfstream II and III, the FAA said. With cost estimates ranging from $850,000 to $1.5 million for the modification, it added, “the cost of the hushkit for the Gulfstream II exceeds the recorded value of the airplane.” Avcon said last week that STC approval of its new hushkit for 20-series Learjets is in the hands of the FAA.