Boeing has been one of the most influential and advanced commercial and private aircraft manufacturer in the world. The company has had an undeniable effect on the modern airline industry as commercial aviation grows into the world’s largest and fastest growing markets. Following World War II, the Seattle based company took an entry into commercial aviation with the Boeing 707, an engineering marvel in 1958, the year it was first introduced to the world. Following since Boeing introduced the 727, a wide body airliner with 3 rear mounted turbojet engines.
Unfortunately however, the 727 experienced little success despite its innovative design. The aircraft had a very poor safety rating. 737 cargo hold problems, engine malfunctions and bulk head failures all contributed to over 300 incidents world wide claiming the lives of over 4000 innocent people. Boeing needed a new return and a new generation of smaller, fuel efficient and safer aircraft to enter the late 20th century. The 737 was introduced in 1967, a narrow bodied single aisle airliner. And low and behold, the 737 experienced massive success over its 50 plus years in service with over 10,000 units built, making it the best selling airliner in the world. A title it still holds today.
The latest generation of the Boeing 737 is the 737 MAX lineup. A revived and modernized re-iteration of the popular 737, the 737 MAX’s bring fuel efficiency and aerodynamics to the top of the priority list. This latest generation of the 737 bring some unique updates and changes as follows:
- A brand new CFM LEAP-1B turbofan engine. Thrust: 29,317lbs.
- 11-12% reduction in fuel burn and 7% reduction in operating cost.
- Fly-by-wire spoiler system, to improve production flow, reduce weight and improve stopping distances.
- New tailcone to improve aero efficiency and reduce fuel burn by 1%
- Advanced technology winglets which feature upward and downward-directed composite airfoils
- Longer nose gear extension (15-20 cm)
- Four 15.1 inch LCD cockpit display screens in landscape orientation.
- New electronic bleed air system, allowing for increased optimization of the cabin pressurization and ice protection systems.
- Updated EEC software, fuel and pneumatic systems.
Despite all these incredibly advanced innovations put into the 737, the 737 MAX has been receiving bad names today due to two fatal incidents involving two units of the 737 MAX 9 aircraft, operated by Lion Air and Ethiopian Airlines. The former accident occurred in October 2018 when a Lion Air 737 MAX 9, only a 5 month old aircraft, crashed into the Java sea killing all on board. The latter has been stirring up modern news and the aviation industry as an Ethiopian Airlines 737 MAX crashed near Addis Ababa on March 10th, 2019. Just 5 months after the Lion Air crash in 2018.
Initial reports indicated that the Flight 302 pilot struggled to control the airplane, in a manner similar to the circumstances of the Lion Air crash.A stabilizer trim jackscrew found in the wreckage was set to put the aircraft into a dive.Experts suggested this evidence further pointed to MCAS as at fault in the crash. About 30 of the 737 MAX aircraft were flying in U.S. airspace when the FAA grounding order was announced. The airplanes were allowed to continue to their destinations and were then grounded.
The MCAS System
The Maneuvering Characteristics Augmentation System (MCAS) flight control law was introduced on the 737 MAX to mitigate the aircraft’s tendency to pitch up due to the aerodynamic effect of its larger, and heavier, and more powerful CFM LEAP-1B engines and nacelles. The stated goal of MCAS, according to Boeing, was to make the 737 MAX perform similar to its immediate predecessor, the 737 Next Generation. The FAA and Boeing both refuted media reports describing MCAS as an anti-stall system, which Boeing asserted it is distinctly not. The aircraft had to perform well in a low-speed stall test.
The impetus for Boeing to build the 737 MAX was serious competition from the Airbus A320neo, which was a threat to win a major order for aircraft from American Airlines, a traditional customer for Boeing airplanes. Boeing decided to update its venerable 737, first designed in the 1960s, rather than creating a brand-new airplane, which would have cost much more and taken years longer. Boeing’s goal was to ensure the 737 MAX would not need a new type rating, which would require significant additional pilot training, adding unacceptably to the overall cost of the airplane for customers. Boeing considered MCAS a hidden detail of the flight control system and did not describe it in the flight manual nor in training, based on the fundamental design philosophy of retaining commonality with the 737NG.
This rush to refresh and update an aging fundamental design of the Boeing 737 is what many experts and analysts in the aviation industry led Boeing to develop such a flawed design in the 737 MAX. As of June 2019, Boeing MAX planes are still grounded in the US and production of the aircraft has been cut by over 10 planes a week.