Boeing has selected a 68-inch fan diameter for the CFM LEAP-1B engine for its new 737 MAX family and reveals it has now received...

Boeing has selected a 68-inch fan diameter for the CFM LEAP-1B engine for its new 737 MAX family.

The manufacturer says the Boeing 737 MAX has continued “to receive overwhelming acceptance from customers”. Boeing reveals it has now received order commitments for more than 600 aircraft to date from eight airlines, up from 496 aircraft from five airlines when the program launched in August.

According to Boeing, the 737 MAX program is on schedule in terms of internal design-configuration milestones. The manufacturer says it continues to focus on engagement with customers and partners to optimize the engine core architecture. Firm configuration for the 737 MAX family is scheduled for 2013. First flight for the 737 MAX is scheduled in 2016, with deliveries to customers beginning in 2017.

Boeing has named its new, re-engined 737 family the 737 MAX and the capacity-equivalent of the 737-800 (the highest-selling version of the 737NG family) is to be the 737 MAX 8

“The 737 is a more efficient, lighter design and requires less thrust than other airplanes in this class, which is important because weight and thrust have a significant effect on fuel efficiency and operating costs,” says John Hamilton, 737 chief program engineer.

“With airlines facing rising fuel costs and weight-based costs equating to nearly 30 per cent of an airline’s operating costs, this optimized 68-inch fan design will offer a smaller, lighter and more fuel-efficient engine to ensure we maintain the current advantage we have over the competition,” adds Hamilton.

The new 737 family will be powered by CFM International LEAP-1B engines. Boeing says the new-engine 737 family will burn 10 to 12 per cent less fuel than current 737s.

Boeing claims the 737 MAX family will also have a 7 per cent operating cost advantage over the competing Airbus A320neo family, which is offered with CFM LEAP-1A and Pratt & Whitney PurePower PW1100G geared-turbofan engines.

The Boeing 737 MAX 9, the biggest model in the new, re-engined 737 MAX family, corresponds to the 737-900ER model in the 737NG family

At the lower end of the aircraft-size scale, fuel-burn comparisons against the competing Bombardier CSeries family, which is powered by the PurePower PW1500G engine, are not yet clear.

Bombardier said earlier this week that, together with data from flight-testing of the PW1500G, final results from five years of wind-tunnel testing of the CSeries design have validated the Canadian manufacturer’s predictions that the CSeries family will burn 20 per cent less fuel than comparably sized existing jets. Among such aircraft are the Boeing 737-700, the Airbus A319 and the Embraer 190 and Embraer 195.

Boeing says the 737 MAX family will have the capacity for increased range, while providing better fuel-efficiency than today’s 737 family.

The manufacturer also makes the claim that, when 100 aircraft of the 737 MAX family are compared to a fleet of 100 of today’s most fuel-efficient aircraft of comparable size, they will emit 277,000 fewer tons of CO2 and save nearly 175 million pounds of fuel per year, which translates into $85 million in cost savings.

Boeing says its new family of re-engined 737s – the 737 MAX 7, 737 MAX 8 and 737 MAX 9 – builds on the strengths of the Next-Generation 737

Boeing expects the fuel burn of the 737 MAX family to be 16 per cent lower than the current A320 family and 4 per cent lower than the A320neo family, though Airbus has said that engines and new ‘Sharklet’ wing-tip devices combined will make the A320neo family at least 15 per cent more fuel-efficient than today’s A320-family jets.

The Boeing 737 family is the world’s most-ordered commercial jet transport, having won orders for more than 9,000 aircraft since the first 737 version, the 737-100, entered service in 1967.

Today’s Boeing 737NG family represent the third generation of the Boeing 737 and the 737 MAX will represent the fourth generation. The A320neo represents the second generation of the A320 family, while the Bombardier CSeries family is completely new.