Tag: airline emergencies

Special engine out procedures, Part 2

There is an old adage that says that being a single-engine pilot minimizes your decision making in an emergency, and there is some truth in that. If your only engine fails, you’re landing.

In a multiengine airplane, you may or may not have options. In a turbine-powered airplane, assuming you have properly loaded the plane and give due deference to published performance data, you will indeed have options. This is especially true on takeoff.

In the FAR Part 121 world that is the airlines, there are certain performance criteria that an airliner must be able to meet, and one of them is the ability to comply with the four segment climb in the event that an engine fails during the takeoff. Most of the time, this isn’t a problem. A properly trained crew can lose the use of one engine, maintain control of the plane, and fly it off the ground safely and figure out where the best place to land will be.

Sometimes, though, terrain or obstacles (or both) preclude the straight-out departure. In this case, there needs to be an alternative procedure. The airlines and manufacturers work the engineers to produce viable options.

These are then tested in the simulator (and probably in a few cases in the real airplane). The procedures are then tweaked and validated and are published. However, they aren’t available in the public domain, because each procedure is ‘owned’ by the airline and/or the manufacturer. Jeppessen, which is the primary producer of aeronautical charts, publishes the procedures as “10-7” pages. And it’s possible that two companies flying the same airplane may have different procedures at the same airport.

Common airports for 10-7 pages, also known as special engine-out procedures, are Las Vegas, Phoenix, or Reno. Most of the time, the issue is terrain, but not always. In a few cases, like Washington National, there may be another issue. Departing Runway 1 at DCA, the issue is Prohibited Area 56 and the fact that a straight-out departure would put you square in the middle of the airspace that protects the White House and the U.S. Capitol.

But terrain is the most common driver of 10-7 development. When I was at the regionals, we had a 10-7 page for Reno that was incredibly complex. The only way to really fly it safely was to brief the first turn and the associated altitude, and then plan on having the nonflying pilot provide a progressive reading of the steps as the flying pilot attempted to fly. In a place like Reno or Vegas, the weather is almost always VFR, so you can plan to maintain visual separation from the rocks. But this isn’t always the case.

Here’s the rub: 10-7 pages are not something the tower is going to be familiar with, so if you have to fly a single-engine procedure, you’ll need to tell the tower that you’re going to be flying a company-specific procedure due to an engine failure. In a high-traffic area, this can get exciting. The best thing you can do is tell the tower to stand by, and do what you need to do to get to a safe altitude and a place where you can trouble-shoot and figure out your plan for getting back on the ground.

A couple of other notes about 10-7 pages: They are often used for a single-engine missed approach as well; and different fleets at airline X may well have different procedures. In fact, it’s possible that some fleets will need a 10-7 page, and others will not.

As a new airline pilot, you can expect an early introduction to 10-7 pages and how to brief them. You’ll also likely get a taste of at least one in the simulator. But, better to see it there for the first time than on the line!—Chip Wright

This is part 2 of a two-part series. See Part 1 here.-–Ed. 

Human factors assumptions, part 1

As I write this, the Lion Air and Ethiopian Air Boeing 737 MAX accidents are still being investigated. While we know that the MCAS system is going to get the major share of the blame, there is also a push to change the way pilots are trained. One of the topics that has come up is one that was addressed in the movie Sully, the story of the USAirways dead-stick landing in the Hudson River, and that is some of the assumptions that go into aircraft and systems design.

Engineers—both hardware and software—creating a new design need to make some basic assumptions about pilot reaction time, knowledge, and experience. Reaction time delay is one of the most difficult things to predict. Modern aircraft are so dependable and so reliable that it’s easy to take them for granted. And that’s the problem: When something does go wrong, it’s critical that the time lag of a response be given adequate consideration. As Sully showed, when the crews in the sim knew exactly what was going to happen and when, and were allowed to respond immediately, they had no trouble getting the crippled A320 back to departure airport, especially when allowed to practice several times.

In reality, though, such events almost never go so smoothly—after all, who ever anticipates losing both engines to a flock of geese? Imagine dealing with the shock of some kind of a collision, followed by a marked change in the normal noise pattern of flight, and then the audible chimes and lights and other indications of an anomaly. Then, once that has begun to set in, the brain has to convince itself that what it is seeing or hearing is real.

Media reports indicate  this happened with the Lion Air and Ethiopian Air crews. Additionally, it involved a system that the crew of the Lion Air flight was totally unaware of, and the crew of the Ethiopian Air flight was only marginally aware of. The noise of the stick shaker—which is extremely loud and distracting in the 737 by design—combined with the realization that the airplane was descending and trimming itself nose down must have been overwhelming. In both incidents, there was surely a realization at some point that the crew was unable to overcome the airloads in order to reverse the trim.

It’s one thing for designers to try to anticipate crew responses during the early phases of flight. But they also need to look at human factors from several angles, including crews that might be in the middle of a longer flight on the back side of the clock, such as a red-eye or a transcon. The effects of fatigue on sensory response need to be accounted for, which is another reason that some warnings are designed to be loud and attention-getting.

The type of fatigue matters too. Is the crew tired because it’s the last leg of a six-leg day, or is it because they are flying in the middle of the night? Crew experience also needs to taken into account. An experienced, well-trained crew is going to have a better response under virtually any circumstance, and there is reason to believe that at least one of the pilots involved in the Ethiopian Air crash may have been extremely low on the experience meter. Throw in a similar situation with fatigue or personal stress, and such an individual could easily be overwhelmed. It might impossible to account for every possibility, but realistic common denominators need to be established.

Manufacturers do what they can to test their theories and assumptions in the simulators, but there are limits to the effectiveness. Every pilot knows that during a sim flight, something will go wrong. They may not know what, or when, or where or how, but they are primed for a surprise, so even the surprise isn’t a total surprise. Further, when you know that you’re in a box, you know that you’re eventually walking away. That means that the effect of full-blown fear and panic is almost impossible to test for or measure.

There has already been much discussion about human factors assumptions moving forward as result of these accidents, and it’s a discussion that will go on for some time. Checklists and procedures are already being retested, rewritten, and studied. Pilots have complained for years that inexperienced cockpit inhabitants—usually first officers—are unable to cope with a sensory onslaught of often conflicting information. These accidents seem to bring some evidentiary data to that argument, though we must wait for the final reports to be written.

What we do know is that 346 people were killed in very preventable accidents, and the laws are written in blood. Changes will be coming.—Chip Wright

SWA 1380

As I write this, Southwest 1380 has already started to fade from much of the public memory. Much has been made about the way the crew responded to such an explosive event—explosive in more ways than one. Nobody ever really anticipates or expects to deal with an engine that blows up in flight, let alone one that also breaks a window and generates a sudden decompression of the cabin.

That said, there is training for something like this. Most airlines in the United States have transitioned to advanced qualification program (AQP) training. Without getting into the nitty-gritty details, part of AQP includes flying scenarios in the simulator that represent real flights between two regular cities, with some kind of a snafu thrown in for the crew to handle. Some scenarios will force a diversion, and some won’t; some are deliberately vague enough that some crews will divert and some will not.

Southwest recently put its crews through an event that included a catastrophic engine failure in cruise  United did the same with its 737 crews a couple of years ago). I don’t know if the scenario included the decompression, but an engine failure is handled almost the same way in either scenario. Like many transport jets, the 737 is designed to fly at or near the highest MEAs on one engine, and it will level off at 22,000 to 24,000 feet at maximum weight on one engine. Obviously, in the case of 1380, that kind of level-off wasn’t possible, but the initial response is the same: Get the airplane into a descent while maintaining a safe airspeed. With the decompression, the goal is to get down to 10,000 feet as quickly as possible so that passengers don’t need oxygen.

Every airplane will respond differently to an engine failure. A wing-mounted engine will cause substantial yaw—possibly a noticeably rolling motion that needs to be addressed fairly quickly. The crew of this flight likely needed a few seconds to register just what had happened—after all, in the sim, everybody already knows what’s coming, but this was real. The immediate response to the cabin pressure change would have been to don their oxygen masks while regaining control of the plane. That means turning off the autopilot (or silencing the disconnect alarm), setting power on the operating engine, and retrimming. This is the “aviate” part of aviate, navigate, communicate.

Every airline dictates who will do what during an emergency, and the final report from the NTSB will spell out how the crew determined who would fly and work the radios versus running the checklist. In this case, there were at least three non-normal checklists that needed to be completed: the engine fire/severe damage checklist, the decompression checklist, and the single-engine approach and landing checklist. The crew at some point also needed to make contact with the cabin crew to get an assessment of the extent of any injuries or damage in the cabin. They likely also asked the flight attendants what they could see out the window as well—and this all happened while dealing with a tremendous amount of noise thanks to the hole in the window.

In spite of the fatality on board, the crew appears to have handled this event as well as or better than expected. No doubt the relatively recent sim event brought a sense of familiarity with the situation, and their years of combined experience helped produce a successful outcome. Like many, I’m already curious to see what the final report will say; expect to see it sometime next winter or spring.—Chip Wright


As I write this, we are only a few days removed from the in-flight engine failure on Southwest 3472, a Boeing 737 that experienced an uncontained failure of the left engine just after reaching its cruising altitude.

While the cause of the incident is far from being determined or disclosed, one thing is clear: The pilots did a great job of getting the airplane on the ground safely as quickly as possible while complying with the appropriate checklists.

Larger airplanes generally have a book called the Quick Reference Handbook (QRH) on the flight deck to deal with certain emergency or abnormal conditions. Printed by the manufacturer initially, the book can be modified to a degree by the operating airline with the consent of the manufacturer and the FAA. The modifications usually take into account certain equipment configurations and/or operational experience that leads the airline to think there may be a better way to execute a certain procedure.

The QRH is usually compartmentalized in one of two ways. The first is to have all of the Emergency procedures in one section, subdivided by the various systems (usually alphabetically). The Abnormal/Caution section then follows, also broken down by each aircraft system.

The second method is to simply list all of the systems in alphabetical order and then spell out the various procedures within each chapter. Emergencies will still be first, followed by an alphabetical listing based on the problem or indication presented to the crew.

The checklist will then go through a process of confirming what problem has been presented, and then a series of corrective actions is presented. This will be often be followed by some IF/THEN scenarios that talk the crew through troubleshooting. The IF/THEN steps can be confusing, and a tremendous amount of time is dedicated to minimizing the possibility of mistakes.

In a case like the one of SWA 3472, the crew would have run a Severe Engine Damage procedure that would have had them systematically prevent further damage by shutting down fuel flow to a potentially burning engine. Once the engine (or what was left of it) was secured, the next step would be getting the auxiliary power unit (APU) started. The APU is a small turbine engine in the tail of the airplane that has a generator for providing electricity and air conditioning. While it’s primarily used on the ground, it is designed to be a back-up source of electrical power in flight.

Once the emergency is stabilized and an appropriate destination is determined, the next step is getting the airplane properly configured for a single engine landing. Fortunately, this is driven home in training, and for each airplane, the setup is pretty consistent. In the 737, the flaps will be limited to 15 degrees, as opposed to the usual 30 or 40. The 15-degree setting greatly improves performance in the event of a single-engine go around. Approach speeds will be computed accordingly, and they will be higher. All of this could affect which airport might be suitable for the landing.

An airport that the airline already serves as the alternate is always the first choice, but it isn’t always the best choice. A suitable airport will be one that has crash/fire/rescue capability, but it may not be a station for your company, and while that can create some logistical nightmares, passenger, crew, and equipment safety is the most important consideration.

Engine failures and other major malfunction emergencies are, fortunately, rare. Preparation and good training are the key to success, along with keeping calm. The old adage of aviate first, navigate second, and communicate third always applies, and it doesn’t matter what kind of airplane is involved: You have to maintain control first before doing anything else. Then, and only then, can you use the QRH—and any other resources—to help save the day.—Chip Wright