Update, 2:15 PM PDT: Airbus issued this response to the Boeing development:
“This kind of split-tip device was among the options we studied for the A320 Family, and we decided instead to advance with our Sharklet design as the most efficient. Our Sharklet figures (3.5% improvement over the already-efficient A320 wing with wing-tip fences) are flight-test proven.”
Boeing today announced a revised winglet to add 1.5% in fuel efficiency for the 737 MAX, releasing a photo. See here. This will be on top of the advertised 10%12% fuel burn gain previously announced.
Separately, David Hess, CEO of Pratt & Whitney, told the PW media day “that as far as we know, the 737 MAX is not an opportunity for us,” citing the Boeing-CFM exclusivity agreement.
Update, 0900 PDT: Boeing held a tele-press conference to discuss the new “Boeing Advanced Technology Winglets,” (BATW) which it also called “dual feathered” winglets.
Boeing said this is an exclusive Boeing design and not derived from a similar design promoted by Aviation Partners. Key points:
- Up to 1.5% lower fuel burn, depending on the length of mission;
- The design used Computational Fluid Dynamics to design it, a process used from the 787/747-8 programs;
- This is completely new technology, not having roots to the MD-11 which has a similar-looking wingtip arrangement;
- The wingspan is increased by only “inches” compared with the NG;
- The BATW is likely scalable to larger aircraft;
- There are no current plans to make the BATW available on the NG, though this could change;
- Although there will be some benefit to range, the BATW isn’t significant;
- Boeing now claims 18% better all-in costs than the current Airbus A320 (based on figures as a starting point Airbus disputes);
- This just about does it for aerodynamic changes to the 737; architectural changes should be nailed down in the third or fourth quarter; and
- “Our major trades aerodynamically are done.”
Aviation Partners has a similar concept; the differences between Boeing and AP are evident.
Here’s how McDonnell Douglas executed a similar concept on the MD-11: