An FAA supplemental type certificate (STC) issued to Trolltune promises to help operators of Gulfstream IIBs and GIIIs fly within strict noise limits at Van Nuys Airport (VNY) in Southern California. The STC isn’t a Stage 3 hush kit, explained Trolltune president Tom Storli, but limits maximum takeoff weight to 64,000 pounds, thus cutting takeoff noise by three decibels–to 79.8 from 82.8–enough to meet the new Van Nuys limit of 80 dBA. This limit is a City of Los Angeles ordinance that takes effect on January 1 next year.
Stage 2 airplanes have not been able to take off at Van Nuys between 10 p.m. and 7 a.m. for many years, but they can land at any time. However, as of Jan. 1, 2016, no Stage 2 operations will be allowed in the lower 48 U.S. states, so the Trolltune STC provides two years of operating relief at Van Nuys for GIIB/GIII operators.
While the STC is simple to accomplish with a placard and some paperwork, Storli spent two years researching and flight-testing the mod. The Trolltune STC costs $40,000, although the price will rise to $50,000 as the January deadline nears, Storli told AIN.
Because older Gulfstream values are so low, he explained, operators may be balking at the cost of Stage 3 hush kits. “Others want to defer that decision, and my STC allows them another two years to decide in the case of Van Nuys.”