Boeing delivered to United the Next-Generation 737-800 that was used as the flying test bed for the performance improvement package. The airplane played a key role in testing and certifying the performance improvement package now available on Next-Generation 737s, Boeing said in a statement today. Boeing began performance improvement testing in November 2010 with the goal of reducing fuel consumption by up to 2 percent. For customers, that would mean saving an average of US$120,000 per airplane, per year, based on current fuel prices. The result of the testing is a package of performance improvements that includes aerodynamic shaped anti-collision lights, streamlined slat and spoiler trailing edges, wheel well fairings re-contoured to smooth the air flow near the main landing gear and a redesigned environmental control system exhaust vent. Meanwhile, CFM has introduced the new CFM56-7BE, an enhanced version of its already fuel-efficient engine. The improved design engine includes a high and low pressure turbine modification which is now standard on all production 737s. \"The improved fuel savings is part of our commitment to deliver market-leading value to Next-Generation 737 customers,\" said John Hamilton, vice president and chief project engineer 737 program. With the testing done on the United airplane, Boeing was able to begin delivering last month the Next-Generation 737s featuring the performance improvement package. The delivery becomes United\'s fifth 737 with the Boeing Sky Interior. The new interior introduces new lighting and curving architecture that create a distinctive entry way. Passengers enjoy a greater sense of spaciousness in the cabin in an environment simulated by light-emitting diode (LED) light. The new interior also features decorative sculpted sidewalls, newly improved and expanded pivot stowage bins. The airplane delivered to United last week marked the final 737 delivery for the carrier in 2011. United took delivery of three 737-800s and one 737-900ER (extended range) earlier this year. In 2012, United will take 19 Next-Generation 737-900ERs.