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Boeing 737 Max Jets Grounded By FAA Emergency Order (nbcnews.com)
President Trump announced an emergency order from the Federal Aviation Administration on Wednesday grounding Boeing 737 Max jets in the wake of an Ethiopian Airlines crash Sunday and a Lion Air accident in October that together killed 346 people. The emergency order comes two days after the FAA said the Boeing 737 Max planes are still airworthy. NBC News reports: Trump's announcement came as the FAA faced mounting pressure from aviation advocates and others to ban flights of the planes pending the completion of investigations into the deadly accidents. Sunday's crash killed 157 people and the one in Indonesia in October left 189 dead. "We're going to be issuing an emergency order of prohibition to ground all flights of the 737 Max 8 and the 737 Max 9 and planes associated with that line," Trump announced, referring to "new information and physical evidence that we've received" in addition to some complaints.
The FAA said it decided to ground the jets after it found that the Ethiopian Airlines aircraft that crashed had a flight pattern very similar to the Lion Air flight. "It became clear that the track of the Ethiopian flight behaved very similarly to the Lion Air flight," said Steven Gottlieb, deputy director of accident investigations for the FAA. United States airports and airlines reacted to the order Wednesday, acknowledging that it will lead to canceled flights. American has roughly 85 flights a day on the Boeing Max 8 and Max 9 jets. United Airlines has about 40 such flights. Southwest Airlines has the most, about 150 flights per day on these types of jets out of the airline's total of about 4,100 flights daily.
The FAA said it decided to ground the jets after it found that the Ethiopian Airlines aircraft that crashed had a flight pattern very similar to the Lion Air flight. "It became clear that the track of the Ethiopian flight behaved very similarly to the Lion Air flight," said Steven Gottlieb, deputy director of accident investigations for the FAA. United States airports and airlines reacted to the order Wednesday, acknowledging that it will lead to canceled flights. American has roughly 85 flights a day on the Boeing Max 8 and Max 9 jets. United Airlines has about 40 such flights. Southwest Airlines has the most, about 150 flights per day on these types of jets out of the airline's total of about 4,100 flights daily.
A clean-sheet design would absolutely have better positioning of the engines. Unfortunately, the 737 platform comes from an era of much smaller engines, so there just isn't enough under-wing clearance to fit modern turbines in the original locations (even versions with engine updates from 10-20 years ago have odd bulges around the nacelle where parts had to be relocated to fit).
The MCAS system was implemented because the 737-MAX engines are placed more forward of the wing which will tend to induce a nose up pitching moment particularly at high angles of attack near stall. This would've probably been a certification issue.
Now the 737 MAX had the engines placed so far forward to enable enough ground clearance. The original 50-year old 737 had low bypass engines which much smaller and could be placed directly under the wings. The newer models already ran into ground clearance issues, and this was initially solved by putting the engine systems to the side of the engine creating a distinct ovoid nacelle shape. With the new GE Leap engines, this fix was no longer sufficient due to larger engine diameter, hence the repositioning forward.
Newer aircraft like the airbus a300 series and the airbus a220 (bombardier cseries) never had this issue because they were designed to accomodate large diameter newer generation engines. The basic design of the 737 has always suffered from this flaw and really Boeing should have invested in a new aircraft design rather than try to re-engine an aircraft that was never designed for it. This was like fitting a V-12 engine into a model T.
You forgot two other important items:
Made the algorithm rely on only a single sensor reading.
Allowed the algorithm to move the trim so far that it makes it impossible for the pilot to overpower it with the control column.
They could have made the MAX fully fly by wire, with envelope protection - the problem is, they would have lost the type rating it would share with the rest of the 737 family (and 767 and 777), meaning that pilots would have to be retrained to fly the MAX and they couldnt cross-fleet between the versions without that extra training.
But Boeing was chasing the grandfathering that makes variants such as the MAX so cheap to invest in, as it doesn't mean they have to do a full recertification, just a partial recertification, which takes less time and is cheaper.