Before any of this happens, Embraer intends to bridge the gap between current and second generation by introducing a wide-ranging set of systems, avionics, cabin and airframe improvements that will provide a foundation for a transition to the new jet later this decade. “Our strategy is to have the best product now with all the improvements until we introduce the second generation. [It keeps us competitive], so really that investment we are making now will help us while we continue to develop the next E-Jets,” says Affonso.
Honeywell is again involved in the interim upgrade and will supply its Next Generation Flight Management System (NGFMS) for new-build and retrofit installation beginning in 2015. The updated FMS, also used on the Boeing 747-8 and Gulfstream G650, will support optimized flight profiles and include a “cost index” to cut fuel burn. It also includes Honeywell's “Smart Landing” system, which reduces runway excursions, as well as enabling compliance with required navigation performance standards of 0.1 nm. The NGFMS is compatible with Primus 2, further helping the systems and pilot-machine interface transition to the second generation.
The upgrade plan, which Embraer first revealed last month when it announced a recent Republic Airways firm order for 47 Embraer 175s, will be introduced from now through 2015. And “There are other things we are considering for 2016-17,” says Embraer's commercial aviation market intelligence vice president, Claudio Camelier.
The first wave is a fuel-burn improvement package along with a series of maintenance updates, all of which are being introduced this year. Package 1 includes a series of aerodynamic “clean-up” features to reduce drag, along with optimization of the environmental control and anti-ice systems, to reduce excessive use of engine bleed air. The aero package includes fillers to close drag-causing gaps in the horizontal tail, a revised rain deflector over the cabin doors, improved ram air doors in the lower fuselage and low-drag wheel fairings. The package, which builds on updates already developed for the larger Embraer 190/195 in some cases, has been incorporated in new aircraft being delivered last January 2012.
A second fuel-burn reduction package, based on further aerodynamic clean-ups of the APU inlet and anti-collision beacon as well as an all-new wingtip, will begin flight tests in the second quarter of this year. The new wingtip extends overall span by around 9 ft. to 94 ft. 2 in. and replaces the existing vertical winglet. The larger tip, which is angled with a dihedral of 45 deg., imposes added bending load to the wing and is therefore accompanied by local strengthening to the wingbox, skins and stub wing where the unit attaches to the fuselage.
The added low-drag features will be incorporated from 2014 onward as will the first new wingtips, which are due to enter service that year on the E-175. The extended tip follows on the E-190 and E-170 in 2015 and in 2016 on the E-195. “The design has been evaluated in the wind tunnel at transonic and subsonic conditions which validated computational fluid dynamics simulations. We've also evaluated all the low-speed characteristics and the wind tunnel tests have given us a high degree of confidence that the flight tests will confirm these results,” says Camelier.
Together, all the updates are expected to give a 5% fuel burn benefit to the E-170 based on a 600-nm flight, while the biggest beneficiary is expected to be the E-175 which could see fuel burn improve by as much as 5.5%. As the E-190 and E-195 already have some of the drag reduction features, these will see relatively lower improvements of 3.5% and 4%, respectively.
The updates also include a series of systems and avionics improvements aimed at lower maintenance costs, enhanced reliability and optimized navigation performance. They include longer-life LED external lights developed by Wisconsin-based Emteq, which states that the unit is among the first of its type to enter service. Other elements include a revised maintenance plan that extends the basic check interval to 7,500 flight hours from 6,000. The extension is “based on data from experience over about 10 years, and saves the equivalent of one basic check per aircraft around that period,” says Commercial Aviation Programs Vice President Leandro Laia.
To further reduce operating costs, Embraer's upgrade plan also includes installation of a prognostic health management system to monitor equipment and anticipate failures or malfunctions. “The idea is to transform an unscheduled maintenance event into a planned maintenance event with less downtime and less interruption to the flight schedule,” says Camelier, who adds that the system will be available in December 2014.
The following year, it also intends to introduce a scheduled structural health monitoring (SHM) system that involves the installation of fatigue and corrosion sensors in hard-to-access areas of the airframe around the aft doors. “To conduct a visual structural inspection you have to remove the galleys, lavatory, seats, liners and so on, but with the SHM you have electronic sensors that provide the data,” Camelier adds. Embraer estimates the SHM will reduce the time for inspections by 128 man-hours.