Aviation Fleet Solutions is flight testing for JT8D-200-powered MD-80s a hush kit that the company says will meet ICAO Chapter 4/Stage 4 noise requirements set to take effect in January 2006. AFS will hold the STC for the modification, designed and built by Pratt & Whitney; it includes an improved fan inlet liner, a 16-lobe mixer, a muffler and a tabbed nozzle. The hush kit will come in two varieties (heavyweight and lightweight) to meet the noise reduction that operators need to achieve. Installation can be completed on-wing, typically in 80 to 160 hours depending on whether the lightweight or heavyweight option is used.
While in-service MD-80s are not required to meet the Chapter 4 noise standards (the regulations apply only to new aircraft and engine certifications), Pratt & Whitney says EU countries or airports themselves could implement noise-based restrictions that result in landing charges and footprint restrictions for operators of engines that do not meet Chapter 4. AFS expect the STC to become a popular noise solution for airlines, given the more than 1,000 MD-80s remaining in the active fleet. — John Croft
