Embraer E190-E2 Still on Track, Despite Engine Snags

 - February 14, 2017, 9:00 AM
The Embraer E190-E2 prototypes have now flown more than 550 hours and engineers have now frozen the model's aerodynamic configuration. (Photo: Embraer)

The Embraer E190-E2 certification effort continues to progress slightly ahead of schedule, despite the need to “optimize” the flight-test schedule to accommodate production problems involving the Pratt & Whitney PW1000G geared turbofans destined to power all three E2 variants.

Speaking with AIN in late January, Embraer Commerical Aircraft COO Luis Carlos Affonso reported that the three 190-E2 flight-test airplanes had accumulated some 550 flight hours, meaning the program completed approximately one-third of its certification campaign. Embraer expects to fly the fourth and final flight-test article—equipped with a full cabin for evacuation trials and other interior-related systems tests—in two or three months, he added. 

In terms of the flying campaign, the Embraer COO said that the airplane has conducted short takeoff and landing (STOL) tests and high-angle-of-attack testing “with good results,” following the freezing of aerodynamic configuration in the fourth quarter of last year. Affonso further reported that engineers have already arrived at a maximum lift coefficient, flight-test data on which Embraer has submitted to certification authorities for inclusion in runway performance manuals.   

Test flights have shown very little need for aerodynamic changes, he added, apart from “some tweaks” such as what Affonso called small improvements in the slat tracks and landing gear doors to reduce drag. 

Planning a total of 2,000 hours of flight testing, 1,500 hours of which it will need for certification validation, Embraer expects a far more mature airplane at entry into service than in previous campaigns, said Affonso, thanks to the large amount of ground testing planned from the outset of the campaign. The company has already performed more than 30,000 hours of ground testing on the fatigue and static test aircraft as well as integration analysis on the company’s so-called Iron Bird located across town from the São Jose dos Campos assembly hall, in Eugenio de Melo.

Tasks recently finished include tests dedicated to lightning strikes and ground vibration, and recently started test items include VmCG—or maximum control on the ground—and fuel calibration, said Affonso.

The Embraer executive noted that airframers in general perform more ground testing in modern campaigns than they did in the past, largely due to the level of sophistication of new systems and the amount of integration involved.

In Embraer’s case, the company has left even less to chance with its decision to build all of the first three flight-test aircraft with virtually the same level of instrumentation, allowing for relatively easy transfer of duties from one airplane to the other. Although a more expensive approach than what most airframers typically take, it will pay for itself in schedule flexibility, said Affonso.

Even in terms of the program’s production plan, Embraer has take what Affonso characterized as a conservative approach, first building E1s on the so-called hybrid production line to limit risk of introducing the E2s onto a newly reconfigured workstation arrangement. The company plans to start assembling the first production E190-E2 some time during the second half of this year. Although Affonso said the company has decided how many production airplanes it plans to build during the first year, he chose not to reveal the rate, saying only that, again, Embraer will not risk a too ambitious approach.

I would say we have taken a relatively conservative approach in terms of production ramp up for the first year,” said. “So our ramp-up is not too steep in the first year; we did not yet make public how many we will build but we don’t want to accelerate too much. So one of the consequences of that is that we’ll have more time to start building the production airplanes. So then the first airplane will be more mature, it will be more advanced in our test campaign.”

Addressing the subject of Pratt & Whitney’s production problems involving the PW1000G geared turbofans destined to power the all three of the E2 variants, Affonso expressed cautious optimism that the issues would not affect Embraer’s production schedules. “We have the advantage of not being the first, so we expect our engines to be in very good shape for entry into service,” he said.

These are production issues, so we had to optimize our schedule a little bit for the flight-test airplanes, but so far so good,” added Affonso. “They will be solved this year, and so we do not envision our production plan being affected by this, [and] so far Pratt has been very firm that they will provide the engines to us on time.”