The media is gushing over the heroic deeds of an airline captain on Southwest 1380, which suffered an uncontained engine failure. The stories generally do not mention a co-pilot (example) and therefore it would be impressive for this captain to have been the first person to earn a single-pilot type rating for the Boeing 737-700. However, when the airliner checks in with PHL tower, the first officer’s voice is heard on the radio (full audio). Newsweek identifies this pilot as Darren Ellisor. The big safety innovation of airlines is the crew concept and the multi-pilot crew so it is surprising to me that every time a flight makes the news the media gives us the impression that we are back to the 1920s single-pilot airline system (see below for how Captain Sully was apparently by himself in the Airbus).
[Why is the public apparently more interested in a narrative of a lone hero, be it Captain Sully or Tammie Jo Shults, the Southwest captain? Why wouldn’t a story about five people (two pilots plus three flight attendants) working together to achieve a successful outcome actually be more inspiring? Most of us work on teams so why wouldn’t we be more inspired by a story about teamwork?]
For the pilots of this airplane it was like a normal day in the simulator (they actually said as much a couple of days later in an official statement: “As Captain and First Officer of the Crew of five who worked to serve our Customers aboard Flight 1380 yesterday, we all feel we were simply doing our jobs.”). Essentially all airliner or bizjet sim training is single-engine operation following a failure because flying a working jet with a three-pilot crew (bulletproof autopilot, left-seat captain, right-seat first officer) is actually easier than a lot of single-pilot operations in light aircraft (hence the higher accident rate for four-seaters, even when experienced pilots are at the controls). Thus, the “engine failure then land single-engine” is something that a mid-career airline pilot would have done 500 times or more in a sim that is so realistic it can be logged as time in the actual aircraft. A 18-year-old seeking a multi-engine rating on his or her Commercial certificate would have to demonstrate managing an engine failure in a piston twin and then flying a single-engine approach and landing… solo. The applicant who failed to demonstrate this competently to an examiner would fail the checkride and not earn the rating. Similarly the pilot seeking a type rating for a turbojet-powered aircraft, such as a business jet or a Boeing 737, must demonstrate this capability before being legally authorized to fly the aircraft (only as part of a crew in the case of the B737, which requires two pilots minimum).
What did happen from the pilots’ point of view? The plane depressurized, necessitating the donning of oxygen masks (the ones in front are “quick-don” types accessible by reaching behind one’s shoulder) and then a reasonably rapid descent from what seems to have been about 32,000′. The goal is to get down to about 10,000′ where everyone can take off their oxygen masks. At the same time, the airplane would yaw because of the asymmetric thrust (dead engine on one side). The plane would have been on autopilot at the time and therefore the yaw damper would automatically kick in some rudder to counteract the yaw.
Usually the crew divides responsibilities between the Pilot Flying, who manipulates the flight controls and/or supervises the autopilot, and the Pilot Monitoring, who does everything else, including talk to Air Traffic Control (ATC). The Captain and First Officer, both of whom are fully trained to fly the aircraft, swap these roles after each leg of a trip. If something goes wrong, the Pilot Flying will take over the radios and thus free the Pilot Monitoring to dig into the checklists, typically accessible via a “Quick Reference Handbook” (“QRH”; see this example from the Canadair Regional Jet (CRJ) that I used to fly). It is the Pilot Flying’s job to ask for the appropriate checklist, e.g., “Give me the Engine Fire Message checklist” (though the Pilot Monitoring can suggest checklists, e.g., “Would you like the Left Engine Oil Pressure Message checklist?”). There are some items to do from memory, with the two pilots cooperating so that they can agree on which engine is the dead one and should have its thrust/fuel lever cut off, for example.
Airline training stresses the use of the autopilot in an emergency, which frees the human pilots to concentrate on the checklists and not pulling back, for example, the thrust lever on the running engine. The Pilot Flying monitors the autopilot and the Pilot Monitoring is going through the checklists and making sure that items such as gear and flaps are set appropriately at various times.
The Southwest crew was favored with “Day VFR” flying conditions (i.e., it wasn’t dark and there weren’t low clouds over the runway) and were near a super long runway, the 12,000′ 27L runway at KPHL. Once any fire is extinguished, e.g., by cutting off the fuel or blowing the squib on a bottle of fire extinguishing stuff (that’s about as technical as we got in training), the situation on a CRJ is no longer considered an “emergency” but merely an “abnormal” operation and the pilots go to the “Single Engine Procedures, In-Flight Engine Shutdown” checklist. The APU is started so that there is a backup source of electrical power (in case the second engine quits!) and various switches are set up so that the dead engine is secured. Then it is time for “ABNORM 1-9, Single Engine Approach and Landing.” The CRJ checklist calls for landing with partial flaps, thus resulting in a 25 percent increase in landing distance. Full flaps enable landing at a slower speed, but the extra drag means that the remaining engine would be straining to keep the plane on the standard glide path to the runway.
For a plane that ordinarily can land in 5,000′, landing on a 12,000′ runway with one engine is a normal day at the office (sim). As noted above, this is the very situation for which nearly all of airline sim training is directed, albeit usually in uglier scenarios, such as an engine that fails just as the plane is taking off (a “V1 cut”). The wind was favorable on the morning of April 17, blowing straight down the runway at roughly 20 knots (on the recording you will hear the Tower controller saying that the wind is from 280 (magnetic west-northwest) and a plane pointed down 27L would have a magnetic heading of 267 degrees (“27” is short for “270”, a west heading; the L is because there is a parallel 27R and, to avoid confusion, the final parallel runway is “26”)). This reduces the touchdown groundspeed and therefore the landing distance (I was once a passenger on a B737 landing in Ushuaia, Argentina into a 50-knot headwind, which the pilots said was normal for Tierra del Fuego. The airspeed of 120 knots thus translated into a groundspeed of 70 knots, a slower touchdown than a Cirrus SR20 in calm wind conditions!)
Not to take away too much from the pilots’ achievement, but keep in mind that a Boeing 737 on one engine and no pressurization is still a much more capable aircraft than a typical light Cessna, Cirrus, or Piper. The autopilot is much better (if it even exists in the little plane!). The climb performance is better (not that this crew ever needed to climb). There are a lot more redundant systems. That’s why there is the standard joke about the airline captain who rents a Cessna from a flight school and puts “Will be declaring an emergency” in the remarks of the FAA flight plan form. The Tower controller later asks why and the captain responds “I’m going to be down to one engine, one radio, one navigation system, and no autopilot.”
If you’re looking for heroes, though, think about the flight attendants. They’re in the back of the plane with 140+ screaming passengers. There is a hole in the airplane. At least one person has suffered injuries that will prove to be fatal. Others are injured as well. They have received no training for this scenario. (Most flight attendant training, as I understand it, is directed at evacuations once the aircraft has landed.)
Some questions that friends have asked:
Why is the term “souls on board” used in aviation? Why does ATC ask? Does it matter if there are 50, 100 or 150 on board? Answer: They want to know fuel on board so they can figure out how much firefighting gear to bring to the scene and also S.O.B. so that they know when to stop searching for bodies. It is the standard phrase even for quotidian matters such as filing an IFR flight plan mid-air (e.g., if the weather turns out not to be clear as hoped).
What is an “extended final”? Answer: Based on the plan discussed in the ATC recording, the plane was lined up with the runway about 20 miles away rather than the usual 7 miles or so (for instrument conditions; it might be only 1 mile at a crazy airport such as LGA in VFR conditions; I wrote about this). That makes life easier for everyone.
Dumping fuel? Answer: 737 does not have a fuel dump capability. If you’re too heavy to land you fly around in circles for a while or just try to land gently so that you don’t stress the gear. If you’ve got a serious emergency and the plane is already damaged it doesn’t matter. You just land overweight. Remember that the max landing weight is for an incompetent landing and is mostly driven by how much abuse the gear can handle.
Do you think damage to cowling/wing/window affected flight performance in any measurable way? And if so, would autopilot recognize and be able to compensate? Answer: The autopilot will manipulate the controls to achieve its programmed goal, e.g., airspeed of 210 knots or heading of 180 (South). Airplanes are usually at least slightly misrigged so that the autopilot will have to hold a bit of left aileron pressure, for example, to keep the airplane from rolling off course. So slight damage to one wing would be like a worse-than-average rigging.
[If you want to truly scare yourself, read Nine Minutes, Twenty Seconds: The Tragedy & Triumph of ASA Flight 529, about Atlantic Southeast Airlines Flight 529, which suffered a prop failure and ended up with a huge amount of drag on one wing that could not be corrected by feathering or any other pilot action. The twin turboprop couldn’t hold altitude on the remaining engine. Flight attendant Robin Fech proved to be a true hero.]
So… let’s hear it for flight attendants who put their lives on the line every day and don’t get to log multi-engine turbine time or look out the front windows. Also for any passengers who got right on a replacement B737 and took off again from PHL to Dallas or wherever else they were ultimately headed. And let’s try to remember poor Jennifer Riordan, the unlucky passenger who died.
Related:
- Unsafe at any speed: Philip and a piston twin (turbojets such as the B737 are actually much easier to fly after an engine quits because there isn’t a lot of drag from the dead engine)
- Airbus A320 certified for single-pilot operation (makes a similar point from 2009: “News accounts have not spent a lot of ink on the people who did the toughest job in this incident: Shelia Dail, Donna Dent, and Doreen Welsh, the flight attendants.”)
- Recording of Delta 1889 pilots trying to get out of a hail-producing thunderstorm. They can be forgiven for sounding nervous. A thunderstorm is the primary aviation hazard for which there is no
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