As a companion feature to Topic 23-8: The Adverse Effects Created by the Comfort Zone, the following is a NASA ASRS report from a crew that made three ATC clearance errors on what was reportedly a routine, easy flight. (NASA ASRS report #1922237)
This was a flight with 3 different ATC clearance errors that were not all immediately trapped. I was Pilot Monitoring (PM) and the First Officer (FO) was Pilot Flying (PF). We were flying ZZZ1 [to] ZZZ on the ZZZZZ arrival.
First ATC clearance error: The first was to cross ZZZZZ at 250 knots then descend via the ZZZZZ arrival. With the first restriction, the 250 knots at ZZZZZ, we were getting close to it, and I queried the FO about slowing to 250 for ZZZZZ. He slowed down and we crossed it at 250 knots.
Second ATC clearance error: Then we stayed level at our last captured altitude, I think it was 12,000 ft., when I noticed that we had passed our TOD for 8,000 ft. at ZZZZZ1. I told the FO we need to descend best rate immediately, and I quickly saw we weren’t going to make the restriction. I advised, ATC, and they said “Roger”, and to just do best rate down and fly heading 360, and we complied.
Third ATC clearance error: Next we were getting set up for a visual to 28. ATC said to maintain 180 knots to the FAF. When we were still 3 to 4 miles from the fix, the FO began slowing down and asked for flaps 30. Without thinking, I glanced at the speed, and selected flaps 30. Immediately after, I realized what I had done, and told the FO to keep the speed up just under 180. The FO kept the speed mostly in the 175 to 180 range, but initially the speed had dropped almost to 160. I elected not to raise the flaps, because we were already so close we would have to immediately extend them again, and it would complicate the profile. We then finished configured at the FAF. Meanwhile tower gave a 737 instructions to do S-turns. And despite my best effort to vacate the runway quickly, [the aircraft] had to go around.
Pilot’s Analysis: The FO was struggling to remember ATC instructions, and I was not monitoring closely enough to catch the mistakes early enough. I also need to think more before extending flaps when asked. Regarding the 250 knots at ZZZZZ I successfully identified the error and called it out.
- Unnecessary conversation: After that the FO was talking about their previous non-flying job in law enforcement, and some of the remarkable things that he did. While technically we were above 10,000 ft. in the most critical section of an RNAV arrival is not a good time to be talking about anything of any significance. I didn’t want to egg him on, and I just nodded and said that’s interesting, but I didn’t say, “Hey let’s talk about this on the ground or on a longer flight, we gotta work on this descend via”, like I should have. Because of this, I didn’t notice that we had passed the TOD soon enough.
- Automatic habit pattern versus appropriate attention level: Then, on the Visual Approach, I should have given it 1 more second of thought before complying with the FO’s request for flaps 30. I de-briefed the FO on all of this.
- Inappropriate attention level: We talked about how I should have been PM more closely, that he needs to be more aware of ATC instructions, and that descending via an RNAV is not a good time to talk about heavy topics. This was a sloppy flight and we need to better. I need to PM more closely. Especially in an “easy” day in clear VMC when the airspace isn’t busy. It is when everything is easy and quiet and not a lot is going on when I get most complacent and my attention drifts. I need to do something active, like keeping a scanning loop going, checking something, or talking about the descent profile, to help keep focus. This is something I’ve been working on. I’ve been working on thinking more before extending flaps. I need to pause [for a moment] and verbalize the flap speed, before extending flaps to check speed and check if extending flaps makes sense in that point in time. This will help me catch a poor decision to extend flaps.
Notice how all three errors seem to stem from the decreased attention focus of both pilots. This seems to be associated with the flight environment characterized as an “easy day in clear VMC when the airspace isn’t busy”. We can envision two very comfortable pilot with expectations that this was going to be a routine, unchallenging flight that mirrored past routine, unchallenging flights. As I cover in the discussion topic (23-8), a common side effect of settling into a comfort zone is modulating attention level with perceived work level instead of with the phase of flight. Consider the following discussion questions.
- Airline flying is often repetitive and unexceptional. It is very easy to settle into our comfort zone. How does this affect our expectations? How do our expectations change over time? How do they affect our levels of planning, briefing, SA building, and monitoring?
- How much did the crew’s first error effect their follow-on errors? Consider an analogy of a boxer who receives a stunning blow from their opponent. They don’t immediately snap back into full readiness. They take time to get over the stun, rebuild their situational awareness, and respond. Do we see evidence of this residual effect in this crew’s subsequent errors?
- In their analysis of the event, the Captain admits to favoring flightdeck rapport over preserving sterile flightdeck protocols compared with focusing the crew’s efforts on complying with the ATC clearances. They allude to the difference between following sterile flightdeck rules and actually satisfying the underlying objectives. The purpose of sterile flightdeck protocols is to focus the crew’s attention toward planning, monitoring, and executing flightdeck tasks during high consequence phases of flight. During this event, how did their unskillful adherence to sterile flightdeck rules affect their ability to recover from early errors and prevent follow-on errors?
