UAL Union: Pilots Don't Need To Know About All Automatic Systems

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As Boeing pushed to provide airlines with more information on a background auto trim system on its 737 MAX, the head of one pilot union said it’s not necessary for pilots to know the details of every automatic system on an airliner and that they’re already adequately trained to handle runaway trim abnormals.

The auto trim system is called MCAS and is intended to improve pitch characteristics and stall protection when the aircraft is hand flown at high angles of attack and high load factors. Although it’s not directly implicated in the Oct. 29 crash of a Lion Air 737 MAX into the Java Sea, investigators are examining what role it might have played.

Breaking ranks with two other pilot unions and his own Air Line Pilots Association leadership, Todd Insler, chairman of the United Airlines ALPA unit, questioned why ALPA publicly pushed Boeing to provide more information on the auto trim system, insisting that pilots are already well trained to handle any uncommanded trim events. Unions for Southwest and American Airlines and ALPA’s national leadership have been critical of Boeing for failing to provide pilots with documentation on MCAS as they transitioned to the MAX.

“We’re the only U.S. ALPA operator of the airplane,” Insler told Forbes. “We weren’t consulted by ALPA prior to their putting the letter out.” Insler said although MCAS isn’t specifically described in United training manuals, runaway trim procedures are: “You have to manually take control—that is one of the early things they teach you when you fly jets. The procedure is there in our manual, and we practice this over and over again. The first time I see an adverse event, I want to see it in a simulator, not with 300 people behind me,” Insler said in the Forbes report. In an interview with the Seattle Times, Insler compared automated background systems on airliners to watching television. “I don’t need to know how it works,” he said.

Indonesian investigators revealed flight tracking data that showed Lion Air JT610 flew sharp pitch, vertical speed and altitude excursions before plunging almost directly into the water 11 minutes after taking off from Jakarta. All 189 people aboard were killed. The aircraft had a recent history of unreliable airspeed indications and an angle-of-attack sensor had been replaced prior to the flight. MCAS—Maneuvering Characteristics Augmentation System—relies in part on data from the AoA sensor. If it detects high AoA at high load factors when the airplane is being flown manually with flaps up, it automatically rolls in nose down stabilizer trim at the rate of 0.27 degrees per second to a maximum of 2.5 degrees. If the AoA condition isn’t resolved, the cycle repeats. The 737 has stabilizer trim cutout switches that inhibit electric trim from functioning and pilots are trained to use these as a standard runaway trim response.

Indonesian investigators say they hope to release a preliminary accident report by the end of November. Meanwhile, shortly after the crash, Boeing sent information on MCAS to MAX operators and the FAA followed up with an emergency AD describing failure indications and responses.    

Comments (10)


I may not have to know how every electron inside a "smart" TV works but I sure need to know I have one and how to work it and that it could do things I don't want it to! That this guy is in opposition to other pilot unions is likewise suspect?

Now I'm going to have to query a friend high up in the UAL flight ops hierarchy to see what HE thinks. I'm betting he disagrees with this assessment! I sure do.

Posted by: Larry Stencel | November 18, 2018 8:24 AM    Report this comment

Is there CVR and FDR information yet?

Posted by: Jason Baker | November 18, 2018 10:13 AM    Report this comment

Todd Insler is "just a bit outside". If the ignorant are flying Boeing, I ain't goiin'.

Posted by: Rafael Sierra | November 18, 2018 11:27 AM    Report this comment

Good grief.
More testimony in favor of autonomous aircraft. Oy.

Posted by: YARS (Tom Yarsley) | November 18, 2018 11:39 AM    Report this comment

We are flying on US 1156 in May from BWI to SFO, please tell me CAPT Insler will NOT be on the flight deck. I really don't want a pilot that doesn't think he needs to know how the automated systems on his aircraft work.

Posted by: Kenneth Sabel | November 19, 2018 4:45 AM    Report this comment

"The aircraft had a recent history of unreliable airspeed indications and an angle-of-attack sensor had been replaced prior to the flight. "

THOSE errant devices have doomed many modern passenger airliners who's crews did not react properly. Those crashes were all WITHOUT a MCAS trim system. Knowing or not knowing that subsystem becomes irrelevant if the crews are already in deep doo doo because of primary instrument malfunctions.

Lets just say that if you don't have reliable airspeed and attitude information that flying any heavy multi-engine passenger airliner can overwhelm a flight crew in short order.

Posted by: Mark Fraser | November 19, 2018 7:36 AM    Report this comment

Reacting appropriately to a Trim Runaway does not require knowledge of the underlying cause. Time yielded to mentally parsing possible causes the runaway is time given over to the deteriorating situation. In a worse case restoring trim position after arresting the runaway is impossible. There may be other situations in which knowledge of MCAS is useful even critical. Reacting to Trim Runaway does not, to this observer appear to be one of them.

Posted by: C. David Buchanan | November 19, 2018 9:54 AM    Report this comment

I wonder if Mr. Insler would think that this would apply:
"Before beginning a flight, each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight."

I bet the Lion Air pilots would have found this information..... enlightening.


Posted by: Blake Mantel | November 19, 2018 3:50 PM    Report this comment

The above two posts encapsulate the benefits and limitations of detailed system knowledge.

There is no time for analysis when the aircraft is departing controlled flight. On the other hand, if the preceding crew had a detailed understanding of the MCAS they very possibly would have rejected the airplane until the problem was fully sorted out to their satisfaction.

Posted by: kim hunter | November 19, 2018 10:57 PM    Report this comment

" The 737 has stabilizer trim cutout switches that inhibit electric trim from functioning and pilots are trained to use these as a standard runaway trim response." Yes, but will these switches also cut off the MCAS system? Mr. Insler seems to be making a precarious assumption at this point.

Posted by: Warren Webb Jr | November 22, 2018 11:02 AM    Report this comment

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