Looking into the Alaska Airlines fuselage case, NTSB will examine door plug, bolts
STEVE INSKEEP, HOST:
Can a president order the murder of a political opponent and get away with it? A federal appeals court considered that question as former President Trump looked on, and we will hear the arguments in a moment. First, we follow up on a story of interest to many people who fly. It's the aftermath of an Alaska Airlines flight that made an emergency landing after a panel came off the side of the plane. The nearest seats were empty, which may be why this incident wasn't even more disturbing. Boeing has updated instructions for inspection and maintenance. Some 737 Max airplanes are grounded. But what now? The National Transportation Safety Board investigates safety incidents and tries to figure out how to keep them from recurring. And Jennifer Homendy is chair of the NTSB. She's on the line. Good morning.
JENNIFER HOMENDY: Good morning.
INSKEEP: I grant that these things take a while to reach final conclusions, but do you feel you understand pretty much what went wrong?
HOMENDY: Well, we know what broke. The components on the top of the door plug fractured, which allowed the plug to be violently expelled from the plane. The bolts that hold those components in place - we don't know whether those bolts themselves also fractured, were loose or whether they weren't even installed on the door. And that's something we're going to have to determine when we get that door plug to the lab.
INSKEEP: Oh, so you just told me something I didn't know. You know that some pieces fractured, but that some bolts - you don't know - might not even have been in there in the first place. Somebody might have forgotten?
HOMENDY: We don't know. Those bolts could have fractured. They could have been loose, or they weren't there. So when we get the door plug, we're going to pack that up today and send it back to our headquarters in Washington, D.C., where we have labs. And our metallurgists will begin examining those pieces and other components. But they're going to want to look at those fittings at the top of the door plug to see if they can tell if the bolts were installed. They will be able to figure that out, because they'll be able to see witness marks. If the bolts were installed, that would be present.
INSKEEP: I'm glad you mentioned the lab. I'll just note that they're a bunch of professionals who work on plane crashes and other kinds of disasters and try to figure them out after the fact, and that's what's happening now. Let me ask about the human role here. We're told, anyway, that warning lights were illuminated on this flight three times, involving the pressurization in the cabin, and apparently this was in some way disregarded. Should this plane have been flying at all?
HOMENDY: Well, those warning lights, we - first of all, we have a team that is looking at those warning lights. At this time, we have no indication that those warning lights were in any way related to the expulsion of the door. And let me just take a second to describe that. That system monitors and adjusts cabin pressure and - automatically. There's a primary system, there's a secondary system and there's a manual system. So there are two backups on the aircraft. It's a triple redundant system. We know the two other systems were working on the aircraft, and the Federal Aviation Administration allows airlines to continue flying the aircraft with those other backup systems. So in this case, what we want - we do want to make sure there was no linkage, so we are pulling the memory cards and looking at the maintenance and testing that was done on those systems.
INSKEEP: So you're saying that there was a redundant system and, even with this problem showing up, that they could fly again. But I'm remembering a recent flight where the plane didn't even ever get off the ground. We ended up leaving the plane because there was some internal panel, one of those plastic panels that isn't even, like, important to the structure of the airplane, that was loose. That was too much. It's surprising to me that any small problem at all of this sort would allow the plane to take off.
HOMENDY: Yeah. And that's something we're going to look at as part of this investigation. Because we're an independent federal agency, we also look at not just the operator, not just the humans involved and the machine and the environment in which they were operating. We also look at federal standards and oversight of the operator and the manufacturer by the Federal Aviation Administration.
INSKEEP: How soon would you expect the other 737 planes that have been grounded to be cleared?
HOMENDY: Well, that is a decision by the FAA.
HOMENDY: They - we do not have authority to ground or unground those. My understanding is that they are in the process of inspecting those planes and making certain findings and reporting those and repairs. I think it's key, though, in this situation that they know absolutely what occurred here before ungrounding the planes.
INSKEEP: Find out what happened beforehand. Chair Homendy...
INSKEEP: ...Thanks so much.
HOMENDY: Thank you.
INSKEEP: Jennifer Homendy is chair of the National Transportation Safety Board. Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.