NA From Germany, joined Dec 1999, 11588 posts, RR: 9 Posted (9 years 5 months 3 weeks 3 days 4 hours ago) and read 4476 times:
In 2000 Aviation partners tested huge blended winglets on a 742 freighter, registered N639FE, a former Fedex/Flying Tigers/SAS airplane (no photo w. winglets available on a.net). Why has no 747 Classic ever been equipped with them. Too expensive? I mean, on a 747, winglets must save $$$, so why was the project quietly cancelled?
I think they have achieved a 7% saving in fuel burn, but don't quote me on that ! So just let's say they reduce fuel burn by 4%, on a thirsty 747 Classic, this means huge savings ! The classics of some operators will be around for some time to come, e.g. Kalitta or MK airlines, so I think the programme would have made sense. IMO the fuel price was't high enough at that time.