Linked List: March 13, 2019

Wednesday, 13 March 2019

‘The World Pulls the Andon Cord on the 737 Max’ ★

Jon Ostrower, writing at The Air Current (Ostrower has been reporting on — and cultivating sources in — the aviation industry for decades):

Every airplane development is a series of compromises, but to deliver the 737 Max with its promised fuel efficiency, Boeing had to fit 12 gallons into a 10 gallon jug. Its bigger engines made for creative solutions as it found a way to mount the larger CFM International turbines under the notoriously low-slung jetliner. It lengthened the nose landing gear by eight inches, cleaned up the aerodynamics of the tail cone, added new winglets, fly-by-wire spoilers and big displays for the next generation of pilots. It pushed technology, as it had done time and time again with ever-increasing costs, to deliver a product that made its jets more-efficient and less-costly to fly.

In the case of the 737 Max, with its nose pointed high in the air, the larger engines — generating their own lift — nudged it even higher. The risk Boeing found through analysis and later flight testing was that under certain high-speed conditions both in wind-up turns and wings-level flight, that upward nudge created a greater risk of stalling. Its solution was MCAS, the Maneuvering Characteristics Augmentation System control law that would allow for both generations of 737 to behave the same way. MCAS would automatically trim the horizontal stabilizer to bring the nose down, activated with Angle of Attack data. It’s now at the center of the Lion Air investigation and stalking the periphery of the Ethiopian crash.

A riveting read.

Several Boeing 737 Max 8 Pilots in U.S. Complained About Suspected Safety Flaw ★

Cary Aspinwall, Ariana Giorgi, and Dom DiFurio, reporting for The Dallas Morning News:

Pilots repeatedly voiced safety concerns about the Boeing 737 Max 8 to federal authorities, with one captain calling the flight manual “inadequate and almost criminally insufficient” several months before Sunday’s Ethiopian Air crash that killed 157 people, an investigation by The Dallas Morning News found.

The News found five complaints about the Boeing model in a federal database where pilots can voluntarily report about aviation incidents without fear of repercussions. […]

The disclosures found by The News reference problems with an autopilot system, and they all occurred during the ascent after takeoff. Many mentioned the plane suddenly nosing down. While records show these flights occurred in October and November, the airlines the pilots were flying for is redacted from the database.

This, more than anything else I’ve read, makes me think it is the right decision to ground these planes pending an investigation. Here the key part of one of the pilot’s reports:

This description is not currently in the 737 Flight Manual Part 2, nor the Boeing FCOM, though it will be added to them soon. This communication highlights that an entire system is not described in our Flight Manual. This system is now the subject of an AD.

I think it is unconscionable that a manufacturer, the FAA, and the airlines would have pilots flying an airplane without adequately training, or even providing available resources and sufficient documentation to understand the highly complex systems that differentiate this aircraft from prior models. The fact that this airplane requires such jury rigging to fly is a red flag. Now we know the systems employed are error prone — even if the pilots aren’t sure what those systems are, what redundancies are in place, and failure modes.

I am left to wonder: what else don’t I know? The Flight Manual is inadequate and almost criminally insufficient. All airlines that operate the MAX must insist that Boeing incorporate ALL systems in their manuals.

(Airworthiness Directives (ADs) are “legally enforceable regulations issued by the FAA in accordance with 14 CFR part 39 to correct an unsafe condition in a product. Part 39 defines a product as an aircraft, engine, propeller, or appliance.”)

Boeing 737 Max Flights Banned by U.S. After Other Countries Ground Planes ★

Ian Austen and Selam Gebrekidan, reporting for The New York Times:

President Trump announced on Wednesday that the United States was grounding Boeing’s 737 Max aircraft, reversing an earlier decision by American regulators to keep the jets flying after a second deadly crash in Ethiopia.

The order came hours after Canada’s transport minister said that newly available satellite-tracking data suggested similarities between the crash in Ethiopia and another accident last October. In a statement released after Mr. Trump’s announcement, the F.A.A. also cited “newly refined satellite data” as supporting the decision to ground the jets. […]

The accidents have put Boeing on the defensive. The 737 Max is Boeing’s best-selling jet ever and expected to be a major driver of profit with around 5,000 of the planes on order. Its shares have fallen about 13 percent this week.

I’m not sure how to bet on how this is going to turn out. My gut feeling until today has been that these two crashes were flukes, and that the similarities between them were just a very unfortunate coincidence. Trump rage-tweeting about the complexity of newer aircraft seemingly put the FAA into a position where they had to ground them, though. And I can definitely see the argument that an overabundance of caution is called for.

Update: After reading about multiple similar complaints filed by pilots about the 737 Max — specifically about problems with the planes going nose down shortly after takeoff — I’m now convinced grounding them pending investigation is the right move, and now I’m wondering why it took the FAA so long to do so.

I also wonder what this means for non-“Max” Boeing 737s — how many air travelers will be spooked just because they sport the 737 name?