How Embraer Developed the ERJ 145 Variants: ERJ 135 and ERJ 140

According to authors Armando Castelar Pinheiro and Regis Bonelli, the main challenges faced by the new owners of Embraer aircraft after privatization were to make the company competitive (after all, in our history on Bombardier, we have already touched upon how the Canadian aerospace giant was developing the Global Express around the same time) and be strategically focused. The new owners of Embraer injected $500 million and "invested heavily in the development and marketing of the EMB 145 model, then renamed ERJ 145".Photo: Lukasz Golowanow | Wikimedia Commons The Role of the Brazil's Public Institutions in Building the ERJ 145 (variants) Brazil's public sector institutions, like FINEP (Financiadora de Estudos e Projetos - Finance Fund for Studies and Projects) and BNDES (a State development bank) contributed to 22% of the development costs of the ERJ-145/135 family. A programme of Brazil's Ministry for Science and Technology called PDTI (Programa de Desenvolvimento Tecnológico Industrial -Industrial Technology Development Programme) was also seminal in the development of the ERJ 145, as Embraer was the largest beneficiary of this program, aimed at "fresh funding and tax holidays to innovating firms". According to Andrea Goldstein, a total of R$ 142 million was assigned to Embraer in subsidies between 1993 and 2000. It was during this time that Embraer's ERJ 145 had been developed: the first flight of this fifty-passenger aircraft occurred in 1995, with initial deliveries occurring in 1996.Looking at the ERJ 145's Performance Capabilities The nose of the ERJ145 was based on the EMB120. The ERJ 145 also had an extended center fuselage. During development of the ERJ-145, Embraer evaluated three competing aerodynamic layouts: a straight wing with over-wing engines, a swept wing with under-wing engines, and a swept wing with engines mounted on the rear fuselage.The over-wing engine layout, derived from the EMB-120 Brasília, was initially attractive because of its low development risk and cost. It reused a straight, unswept wing based on the turboprop design—modified with increased span, winglets, and a thinner airfoil—and stretched the fuselage to seat 45 passengers. Cruise speed was progressively raised from Mach 0.70 to 0.75.The under-wing engine configuration introduced an all-new swept wing (about 26° leading-edge sweep) optimized for higher cruise speeds around Mach 0.80-0.82. However, under-wing engines required longer landing gear and a redesigned nose, increased costs, reduced cabin seating due to emergency slide requirements, and raised concerns about foreign-object damage from engines positioned close to the ground. The rear-fuselage-mounted engine configuration combined the aerodynamic advantages of the swept-wing design with fewer integration compromises. With a rear-fuselage-mounted engine, Embraer eliminated the need for longer landing gear, reduced foreign-object damage risk, and avoided costly fuselage and cabin penalties. Finally, this configuration became the final choice for the ERJ-145. Let's take a look at the configuration of the ERJ 145: Maximum Takeoff Weight (MTOW): 22,000 kg (48,501 lb) Maximum Landing Weight (MLW): 19,300 kg (42,549 lb) Maximum Payload: 5,786 kg (12,755 lb) Maximum Usable Fuel: 5,136 kg (11,322 lb / 6,396 L / 1,690 gal) Maximum Cruise Speed: Mach 0.78 Time to Climb to FL350: 18 minutes Takeoff Field Length: 1,380 m (4,528 ft)2,270 m (7,448 ft)Landing Field Length: 1,400 m (4,593 ft)Service Ceiling: 37,000 ft Range: 1,550 nm (2,873 km)*** Photo: 4300streetcar | Wikimedia CommonsThe ERJ 135 A need for an aircraft that could serve less dense routes than allowed by the ERJ 145 led to the development of the ERJ-135- a variant shortened by 11.6 feet. Equipped with two rear-mounted Rolls-Royce AE 3007A3 turbofan engines, the aircraft offered a range of 1,750 nautical miles (3,240 km) and a maximum takeoff weight of 20,000 kg (44,092 lb). Sharing roughly 96% systems and components with the ERJ-145, the ERJ-135 benefited from extensive commonality across the family, and its test program was completed ahead of schedule in May 1999. The aircraft entered service shortly afterward in July 1999 with Continental Express and American Eagle, quickly gaining favor among operators for its low maintenance requirements and reduced training costs. Here's a look at the companies that provided the components and systems that the ERJ135 needed: Sonaca of Belgium: Pylons, the center and rear section of the fuselage Gamesa of Spain: Wings International Nacelle Systems: Engine Nacelles and Optional Thrust Reversers Hamilton Sundstrand: An Air-Conditioning System EROS: Oxygen system The ERJ 135 is equipped with a retractable tricycle landing gear supplied by Liebherr, complemented by robust Goodrich wheels and brakes. The system features a forward-retracting nose gear and a Hydro-Aire brake-by-wire system, contributing to precise ground handling and braking performance. Propulsion is provided by two Rolls-Royce AE 3007-series turbofan engines mounted on rear fuselage pylons. These engines incorporate advanced digital engine control, while the air intakes are fitted with anti-icing systems to ensure reliable operation in adverse conditions. The standard AE 3007A engines are rated at 31.3 kN of thrust, with the optional AE 3007A1 variant delivering approximately 15% additional power. ERJ-145's smaller variant had already amassed 145 orders by late 1998—less than a year after its launch. American Eagle committed to 75 aircraft with options for another 75 at the 1998 Farnborough Airshow. Continental Express followed closely, placing firm orders for 25 ERJ-135s and options for 50 more. ERJ 140 In September 1999, Embraer launched the third member of its regional jet family, the 44-seat ERJ-140. Like the ERJ-135 and ERJ-145, it was a straightforward derivative design, differing primarily in fuselage length and maximum seating capacity. Photo: Mastrangelo1710 | Wikimedia CommonsThe ERJ-140 completed its first flight on June 27, 2000, with deliveries beginning in late July 2001. The aircraft was developed largely for U.S. operators seeking to navigate pilot scope-clause restrictions limiting the number of 50-seat regional jets they could operate. American Eagle became the launch customer.Here is a look at the specifications:Maximum Takeoff Weight (MTOW) 21,100 kg (46,517 lb)Maximum Landing Weight (MLW) 18,700 kg (41,226 lb)Maximum Payload 5,292 kg (11,666 lb)Maximum Usable Fuel 5,136 kg (11,322 lb / 6,396 L / 1,690 gal)Maximum Cruise Speed Mach 0.78Time to Climb to FL350 16 minutesTakeoff Field Length 1,270 m (4,167 ft)Takeoff Field Length (alternate) 1,850 m (6,070 ft)Landing Field Length 1,380 m (4,528 ft)Service Ceiling 37,000 ftRange 1,650 nm (3,058 km)Interior Configuration 44 seats @ 31 in pitch