Advanced Blended Winglets
The most noticeable feature to appear on new 737's are the winglets. They have been credited to Dr Louis Gratzer formerly Chief of Aerodynamics at Boeing and now with Aviation Partners Boeing (APB). They were first flown on a -800 in June 1998 as a testbed for use on the BBJ. They are now available as a standard production line option for the -700, -800 and BBJ; or as a retrofit from APB and to date approximately 300 737's have them fitted. Boeing is "continuing to assess the applicability" of winglets on the -600 & -900.
|
APB began flight testing
a winglet equipped 737-300 in Nov 2002 which gained its FAA supplemental
type certificate (STC) on 30 May 2003. The STC for the -400 is expected
in 2005. Winglet equipped classics are known as Special Performance
(SP). Other winglet News Stories An excellent article by Boeing in Aero 17 is available at: /www.boeing.com/commercial/aeromagazine/aero_17/winglet_story.html
|
 |
I. Next-Generation 737 Production Winglets
Description
Winglets are wing tip extensions which provide several benefits to airplane operators. The winglet option increases the Next-Generation 737's lead as the newest and most technologically advanced airplane in its class. These new technology winglets are now available on 737-800s as well as on the Boeing Business Jet (737-700 and 737-800).
There are two types of winglet available, Boeing's own built into the wing at the time of manufacture and the APB winglet as a retrofit. At 7ft the APB winglet is slightly shorter than Boeings own at 8ft 2in.
Benefits
Depending on the airplane, its cargo, the airline's routes and other factors, winglets have the potential to give:
IMPROVED TAKEOFF PERFORMANCE
By allowing a steeper climb, winglets pay off in better takeoff performance, especially from obstacle-limited, high, hot, weight-limited, and/or noise-restricted airports. Performance Improved climb gradients increase 737-800 allowable takeoff weight (TOW).
Some examples include:
" Chicago-Midway:
~1,600 lb additional TOW
" Lanzarote (Canary Islands): ~3,500 lb additional TOW
" Albuquerque, Denver, and Salt Lake City: ~4,400 lb additional TOW
REDUCED ENGINE MAINTENANCE COSTS
Better climb performance also allows lower thrust settings, thus extending engine life and reducing maintenance costs. Lower Required Thrust Levels Extend On-Wing Life.
Takeoff - Winglets
allow up to 3% incremental derate.
Cruise - Cruise thrust levels are reduced by up to 4%.
FUEL SAVINGS
Winglets lower drag and improve aerodynamic efficiency, thus reducing fuel burn. Depending on the missions you fly, blended winglets can improve cruise fuel mileage up to 6 percent, especially important during a time of rising fuel prices.
INCREASED PAYLOAD RANGE
The addition of Aviation Partners Blended Winglets to the 737 Next Generation has demonstrated drag reduction in the 5 to 7% range that measurably increases range and fuel efficiency . In addition, the Blended Winglets allow the 737-NG to take off from higher, hotter airports with increased payload.
|
Series
|
Range (nm) Normal
|
Range (nm) With Winglets
|
|
-700
|
3250
|
3634
|
|
-800
|
2930
|
3060
|
|
-900
|
2670
|
2725
|
ENVIRONMENTALLY FRIENDLY
With winglets, you can be a good neighbour in the community you serve. They enhance performance at noise-restricted airports and cut the affected area by 6.5 percent, saving you money on airport noise quotas or fines. By reducing fuel consumption, winglets help lower NOx emissions by 5%.
IMPROVED OPERATIONAL FLEXIBILITY
By increasing Payload Range and Overall Performance, Blended Winglets add flexibility to fleet operations and route selection. Air Berlin notes, "Previously, we'd step-climb from 35,000 to 41,000 feet. With Blended Winglets, we can now climb direct to 41,000 feet where traffic congestion is much less and we can take advantage of direct routings and shortcuts which we could not otherwise consider.
MODERN DRAMATIC APPEARANCE
Blended Winglets bring a modern look and feel to aircraft, and improve customers' perceptions of the reliability and modernity of the Airline.
Dimensions
Each winglet is 8 feet long and 4 feet in width at the base, narrowing to approximately two feet at the tip.
Added wingspan
Winglets add approximately 5 feet to the airplane's total wingspan - from 112 feet 7 inches to 117 feet 2 inches. (All Next-Generation 737 models have the same wingspan.)
Weight
Each winglet weighs about 132 pounds. Increased weight to the airplane for modifying wing and installing winglets is about 480 pounds.
Airplane provisions
Structural modifications to accommodate the winglet include strengthening the wing's centre section and other internal strengthening on the wing. These enhancements are done in the normal production process. Various systems changes have also been made to accommodate winglet installation.
Offerability
Production and retrofit winglets for the Next-Generation 737s are available through Boeing (production) and Aviation Partners Boeing (retrofit). Aviation Partners Boeing (APB) is a joint venture partnership between Boeing and Aviation Partners Inc. (API).
Certification
Retrofit FAA Supplemental Type Certificate (STC) was granted to APB on 3/23/2001. LBA (German regulatory agency) STC was granted to APB on 5/4/2001. JAA STC was granted May 2001. Boeing PLOD (program letter of definition) was granted 5/9/2001 by both the FAA and JAA for Boeing production.
Availability
737-700, 737-800, 737-900, 737-BBJ - available now. Deliveries began May 2001. Initial customers included: South African Airways, Air Berlin, American Trans Air, Polynesian Airlines, and Hainan Airlines - both through direct purchase and leasing options via ILF, GATX, GE Capital Corp., and Flightlease.
Operational Considerations
There is a small difference in rotation rate for airplanes with winglets installed and, as a result, the crew needs to be cautious of pitch rate. There is also approximately a ½ unit take-off trim change between non-winglet and winglet aircraft so the green band is slightly different for winglet aircraft.
II. 737-200 Mini-Winglets
This is a 737-200Adv, L/N 628, fitted with mini-winglets. This is part of the Quiet Wing Corp flap modification kit which gained its FAA certification in 2005. The package includes drooping the TE flaps by 4 degrees and the ailerons by 1 degree to increase to camber of the wing. Benefits include:
" Payload Increase
of up to 5,000 lbs.
" Range Increase up to 3% " Fuel Savings up to 3%
" Improved Takeoff/Landing Climb Gradients
" Reduced Takeoff/Landing Field Length
" Improved High Altitude Takeoff/Landing Capability
" Improved Hot Climate Performance
" Reduced Stall Speeds by 4-5kts
Photo: Julian Whitelaw
10 Jul 2003 - Air Plus Comet Becomes World's First Operator of Boeing 737-300 with Winglets
Air Plus Comet yesterday became the world's first operator of a Boeing 737-300 with advanced-technology blended winglets and the latest carrier in Spain operating Boeing airplanes.
The winglets, which curve out and up from the plane's wing tips, improve an airplane's performance and allow it to fly more than 185km farther than a 737-300 without winglets. Winglets also offer excellent environmental benefits, including reduced fuel use, takeoff and landing noise, and in-flight engine emissions.
"As the first worldwide customer for the new 737-300 blended winglet, we will be the first to experience the fuel savings and environmental benefits they bring," said Alejandro Avila, Air Plus Comet technical director.
The 737-300, leased from Aircraft Leasing Management, was delivered today. Headquartered in Madrid, Air Plus Comet provides long-distance charter flights between Spain and European locations and the Americas. It began operations in 1997.
Aviation Partners Boeing, a joint venture of Boeing and Aviation Partners, Inc., developed the winglets. The winglets can be installed on 737-300, -400, -700 and -800 models. More than 28 carriers fly nearly 300 winglet-equipped 737s.
