Stage 4 Md80
 

From the 1-7 October issue of Flight International:

"Jet Engineering expects this week to start flight testing a Boeing MD-80 fitted with a modified exhaust mixer designed to....compliant with Chapter 4 noise limits. The two-week flight test program at Mojave....on an MD-81 and is due to begin around 4 October. It follows ground tests of the mixer at Pacific Gas Turbines in San Diego, which showed noise reductions and performance improvements. The company says reduced back-pressure from the modified mixer increases the cruise thrust of the Pratt & Whitney JT8D-200 engine by around 500 lb (2.2kN), which translates into a specific fuel consumption saving of between 2% and 3% at reduced power settings. The new mixer, weighing around 20kg (44lb), adds around 0.15m (0.5ft) to the length of the exhaust. Jet Engineering expects noise levels at take-off to be reduced by 2dB at each measurement point, contributing to an overall cumulative noise reduction totaling 10dB."......"Diversified Aero Services, the Florida-based company supplying the testbed, says the modification is expected to save operators which fly about 1000h a year around $1M over the same period. Predicted savings include the elimination of noise-related charges, lower fuel costs, extended economic life, and enhanced market values. Certification of the kit is expected by year-end for all MD-80 variants, with kits available in early 2003."

:D

Wonder how long it will take the brass hats in Brussels to declare that as the MD80 was not stage 4 to begin with...so, it ain't no good.:rolleyes: :eek: