Aircraft Accidents and Frozen Chickens

In 1987, when I took a DC-10 Maintenance class, the instructor showed a film of how they test aircraft windshields (wind-screens) for bird strikes: they launched grocery-bought chickens at the wind-screen using a ‘chicken cannon’ (real thing), which launches the long-expired bird at the test wind-screen at 200 miles per hour (MPH).  Since wind-screens are engineered to be heated and reinforced internally to absorb and deflect a bird strike, this is the only way to test the product for integrity.  The bird strikes the wind-screen, spatters at the high rate of speed and deflects away from the cockpit.  The pilots and aircraft are protected.

A wind-screen designer for high-speed locomotives used the same cannon to test locomotive wind-screens; they are designed to be just as strong.  Using the chicken cannon, the tester launched the chicken at the locomotive wind-screen; the test chicken exploded through the wind-screen, created a gaping hole through the heavy metal control compartment back wall and lodged in the aft structure.  Needless to say, the test was a failure; the locomotive wind-screen manufacturer asked the aircraft wind-screen manufacturer for hints as to make their product better.

The aircraft wind-screen manufacturer replied … and I quote, “Next time you test the cannon, defrost the chicken.”

These are real methods and events; I didn’t make them up; I saw the videos.  I talk about them to emphasize the destructive difference between a bird at ambient temperature, whose structural strength matches your Thanksgiving turkey about to be carved; versus the frozen chicken with the pliability of a rock or brick.

I noticed in the aviation news this week that a surge in Drone activity has resulted in the Federal Aviation Administration (FAA) prompting ‘emergency’ action in regards to Unmanned Aerial Vehicle (UAV) use; an average of 250 safety incidents per month involving near misses between UAVs and aircraft of all kinds, e.g. airliners, private aircraft, helicopters, etc., have been reported.  In addition, the National Transportation Safety Board (NTSB) is investigating a Staten Island, NY, incident involving an Army UH-60 helicopter striking a drone.

Since the professional UAV industry is working tirelessly to acquire aviation industry credibility, let me just say this: Professional UAV industry, you are your own worst enemy.  By allowing UAV lobbyists to confound the media by using adjectives like ‘baloney’ to describe UAV strike dangers; by allowing lawyers with no aviation background to try bullying the FAA; by allowing amateurs to cause FAA emergency actions with their irresponsible behavior; the FAA, the NTSB, Air Traffic Control, Airlines, the Airline Pilots Association (ALPA) and other mainstream aviation organizations will never recognize you as safe to use their airspace.  They have built and occupied that airspace for over seventy years and you need to start playing by their rules.

But, since UAV lobbyists have been misrepresenting the safety implications of a drone or UAV strike, I will defer back to my chicken cannon story to make a point about strength.  I feel it is necessary to make the case for why a UAV hitting an aircraft – any aircraft – is more dangerous than people realize.

And, by the way, the average UAV is represented by the frozen chicken.

Let’s start with the helicopter, particularly the UH-60 in the NTSB accident investigation.  The Sikorsky UH-60 is popularly known as the Black Hawk, as in the 2001 movie, Black Hawk Down.  It is indicative of the design of most helicopters – from the Bell 47 used in the M*A*S*H series to the Eurocopter AS350 employed by police and traffic news stations everywhere – in that it has a Main Rotor for vertical lift and horizontal maneuvering, while the Tail Rotor controls torque created by the main rotor.

Both Rotors’ blades are airfoils, meaning they do not have Leading Edges that are as sharp as a Ninja sword blade; they are rounded to create lift, exactly like an aircraft’s wing.  The blades cannot cut through concrete or metal, like so many action movies portray.  Instead, when ANYTHING hits the Rotor blade’s leading edge, the blade is forced backwards against the direction of rotation; the blade is also structurally compromised or destroyed by the impact.

The Main Rotor turns at 258 rotations per minute (RPM); this means that the tip of the #1 Main Rotor blade passes the same spot in space 4.3 times per second … that’s 4.3 times PER SECOND.  In this case, both the ambient temperature or the frozen chicken would destroy either fragile Rotor Assembly while it is operating.  After the Rotor blade is destroyed from the strike, the Rotor is now out-of-balance; the helicopter is uncontrollable, it experiences incredible vibrational torque forces and the helicopter drops straight down on whatever … or, whoever … is below it, with absolutely no warning.  That is the reality of a UAV strike against a helicopter … any helicopter.  These are not my opinions; these are facts supported by engineering data and accident investigations.  If the UH-60 in the NTSB investigation were struck in either Rotor, all occupants of the helicopter would have been killed … period!

The effects of a UAV strike on a propeller aircraft are similar, except the propeller rotates to provide forward motion; the propeller blades are small airfoils that, like a wing, provide a negative pressure (lift) in front of the propeller that pulls the aircraft forward.  Again, the propeller is rotating at great speeds; when it hits the UAV, the catastrophic results will put the engine propeller shaft out of balance causing extreme torque forces on the aircraft and, in the case of a single engine aircraft, will turn the plane into a glider with enough forward momentum to bring the plane and its occupants to the crash site.

To an airliner, there are multiple dangers.  Any jet airliner approaching an airport travels between 140 to 200 MPH, according to what stage of the landing phase they are in.  Studies have been done that shows UAVs are impossible for pilots to see, because:

  1. The airliner is traveling too fast to sight a UAV, especially at night. The UAV is almost invisible to the naked eye, even when one is looking for it;
  2. The landing phase of flight is very busy. Pilots are lowering flaps, talking with air traffic, lowering the gear, monitoring instruments, e.g. airspeed, altitude; they are too busy to look out the window for UAVs that shouldn’t be there.

Let’s look at the dangers of impact.  First, as demonstrated by the chicken cannon, the UAV can – and will – penetrate the wind-screen; the pilots will either be seriously injured or killed causing all passengers to be killed as a result.

As mentioned in an earlier article, a gull tore through the radome of a B727, went through the metal bulkhead behind it and knocked the Captain unconscious when it exploded in his lap; I know this because I helped repair the damage.  The B727 was moving at about 140 MPH and all three pilots never saw the bird or the flock it belonged to.

And, what about the engines.  Since US Airways, flight 1549, the ‘Miracle On The Hudson’, stands as the landmark example of why bird strikes are survivable, let’s look a bit closer.  An airliner’s engine Fan rotates at around 3600 RPM.  Think about that … each Fan blade hits the same point in the engine inlet sixty times per second … SIXTY TIMES PER SECOND.  Can you imagine the kinetic energy that is generated?

I spoke about the consistency of an ambient temperature chicken – or in US Air 1549’s case, a Canadian Goose – is that of a cooked turkey.  A bird’s bones are hollow; like with the cannon, the carcass splatters against an unforgiving object.  However, in the case of the B727, the carcass of a smaller bird penetrated metal and landed in the cockpit; so, with enough force, even a bird can cause catastrophic damage to metal at 140 MPH.  The flock of Canadian Geese did catastrophic damage to both of US Air 1549’s engines.  Imagine a solid metal-and-plastic object, like a UAV, striking the engines’ blades that are spinning at 60 rotations per second.  Result: DISASTER.  And, US Air 1549 was over water.

The argument about UAVs in the national airspace has to be one of facts, not opinions or sarcasm.  These are dangerous forces, dangerous results and dangerous amateurs.  When even a bird as simple as a chicken can cause catastrophic damage, perhaps we need to be more selective as to how we approach greater threats to safety and lives.

Aircraft Accidents and Gremlins

For Bugs Bunny’s many fans, the 1943 episode: Falling Hare, had the Gremlin, a fun character in that he is one of the few Warner Brothers characters to actually outwit the Brooklyn-ese speaking Bunny.  Designed to resemble a red-nosed, eyelid-drooping imp with wing-shaped ears and an aircraft tail … for his tail, the gremlin wreaked mechanical chaos with the Army-Air Force aircraft, as well as driving crazy said Bunny.

Gremlins were mischievous trouble-makers, discovered during World War II; they purposely sabotaged aircraft for non-political reasons, except, perhaps, for the fun of it.  They were the banes of aircraft mechanics everywhere, making first-age technology malfunction for confusing reasons.  If you don’t believe they exist, ask William Shatner’s character, Bob Wilson, from The Twilight Zone episode: Nightmare at 20,000 feet; Bob Wilson said, in reference to his airplane’s wing, “There’s a man out there.”

I’ve been reading up on what amount to ‘good’ gremlins: little robots that can be used inside the moving parts of a turbine engine, without the benefit of cracking open the engine case.  These little guys don’t resemble Bugs Bunny’s foil, yet they are designed to be small enough to fit into the incredibly small clearances of modern-day turbine engines.

To succumb to the inevitability of technical servants assuming all the skills of their human masters; it’s disturbing.  Making the aviation industry sit down and become aware of technical complacency is like trying to herd cats.  As I’ve written before, it concerns me that we continually trust the technology to solve all our problems and eliminate so much earned experience, e.g. driving our cars or piloting our aircraft, while we engage in texting or conversations about retirement.

I see Labor concerns with this technology.  Again, just like that mythical second officer that supposedly sat behind the Captain and First Officer in the airliner’s cockpit, jobs can and will be taken by, of all things … Robots.  How many man-hours or jobs will no longer be available because of our race to technological dependency?  But, I’m not trying to talk about Commerce.

It would be naiveté to dismiss all new technologies as a threat, in this age of micro-robots.  In its day, technological advances, e.g. the borescope (a flexible lighted wand), that can photograph or provide visual non-destructive inspection (NDI), was the advanced technology for inspecting the inside of a turbine engine; indeed, even the modern jet engine itself, is light years ahead of its older siblings.  But even as one studies the difference between the jet engines used on the B707 as compared to evolved versions used on the later B737 and lastly the B757, the advancements are off-the-charts revolutionary.  But, they also represent that surrender of control.

Chief Scientist Dr. Don Lipkin of GE Global Research, along with his associates Todd Danko and Kori MacDonald, have developed these micro-robots with the intention of utilizing them on jet engines.  This is an incredibly beneficial technology, make no mistake.  The usage is limited now to visual inspection, but there are plans to evolve the robots to conduct repairs.  One must understand, that to effectively inspect a jet engine ‘on-the-wing’ requires access to internal components with clearances of micrometers instead of meters.  Once inside, the robot must maneuver its camera to record images in an area too small for a borescope.

Riding a plastic track, the robots are inserted into the aircraft turbine engine.  They lock onto a set of rotating blades and are spun past the static blades – stator blades – taking pictures; this gives the inspector with a laptop a front row view of the compressor blades.  Other robot versions use magnetic wheels to crawl into the engine and place themselves into an optimum position to get the best inspection view.

In contrast, when employing a borescope, several plugs are removed from the engine casing.  A borescope’s telescoping wand is inserted through the holes and the compressor section is rotated past the scope.  The scope is only limited by its inflexibility; the wand cannot make 180 degree turns in so small a space.  If the inspection cannot be done adequately, the engine must be removed and the casing opened for a more complete visual.  This costs airlines money and time; replacement engines must be provided, man-hours performed and money spent.

Delta Airlines flight 1288 in Pensacola, Florida, July 6, 1996; United Airlines flight 232, Sioux City airport, Iowa, July 19, 1989; and American Airlines flight 383, in Chicago airport, Illinois, October 28, 2016; if a better means of visual inspection were available, these accidents may have been prevented.

This inspection method is considered NDI; the time to conduct the inspection is reduced considerably by using the robots.  As a result, less man-hours are utilized; less personnel to conduct the inspection; and more time the engine is spent ‘on-the-wing’.

It is planned to equip the robots to effect repairs in these tight places, meaning the robots can be utilized during an aircraft’s ground time on the gate.  The ability to make repairs in the confined space of a Compressor section may be, to me, pushing the safety limit beyond its technology.  And this is where someone must delay the technology, or in Bugs Bunny speak, “Apply the air brakes.”  For example, let’s look at one straightforward engine repair job: Blade Blending – a means of filing down damage to a blade.  Blade blending is an allowable procedure, in some instances, depending on where the blade is damaged, e.g. at the tip, or the base and how much material can be blended.  Blending is a minor repair I’ve made countless times; limits are intentionally made for safety.  Although not labor-intensive, the repair can be done wrong or the pre-repair damage can be too extensive, resulting in, and including, blade replacement.

Without the ability to closely inspect the repair, one could induce a hairline crack or burr that could propagate into a complete blade failure, which probably doesn’t sound as bad as it really is.  Imagine, however, a compressor blade breaking free from inside the compressor section as the engine is spinning at 3600 rotations per minute; the engine could suffer further catastrophic damage, including an out-of-balance condition; all this could occur before the pilots could react to the emergency.  With International flights being what they are, this could take place over the ocean, three-plus hours away from a suitable airport.

This is all conjecture; this type of damage may never occur.  However, with parts rotating at such incredible speeds and operating in extreme temperatures that would themselves contribute to failure, perhaps the purposes of the micro-robots should never exceed inspection.  It is my feeling – and experience – that if damage is discovered, then the engine should be split, the parts repaired or replaced under controlled conditions.  It is a useful technology, if only used to its proper degree – no more.

So, when does good technology turn into a gremlin, a force that can destroy instead of help?  When we exceed the design of the technology, hold it to a higher standard than it should be held to.  Kind of like the countless technologies we have become too reliant on.  And, unfortunately, unlike with Bugs Bunny, air brakes don’t work.

Aircraft Accidents and Depleted Uranium

Hollywood has the uncanny ability to remove all realism from just about everything.  Their perception of the mechanisms of an aircraft accident, e.g. the mid-ocean disaster of the FedEx MD-11 in Cast Away is designed more to aid the shot than actually depict the hazards of an actual accident.  Chuck Noland (Tom Hanks’s character) ends up outside the crashed MD-11 in the ocean, surviving the impact, yet almost killed by a still operating #2 tail engine that slowly descends on him.

In Chuck’s case, it’s unlikely our hapless hero gets out of the fuselage unscathed, without getting sliced up on the jagged fuselage’s metal or turned to jelly by the incredible impact forces.  The ocean’s surface, where he’s treading water on, is mostly jet fuel and hydraulic fluid, two liquids that have a lower density than water and therefore float on the surface.  They give off noxious fumes; jet fuel can give a person second or third degree chemical burns, not to mention the damage they would do to his eyes and lungs.  Ironically, the only non-threatening item is the running #2 engine.  Why?  Well, you know that jet fuel feeding the engine?  Hapless Chuck has been splashing around in it on the ocean’s surface.  So, it’s safe to say that a movie set will be arranged for the most advantageous shot; aircraft debris is placed strategically to avoid shadows or block the actor’s close up.

So where am I going with this; what’s the point?  Aircraft accident scenes are very dangerous places.  Rescue workers/first responders face many dangers from the crashed aircraft and even the victims, themselves; things you would never consider hazardous upon arrival at an accident scene, e.g. American 587 in Belle Harbor, NY.

The Airbus A-300 fell onto a Queens neighborhood, killing several people on the ground.  Aside from the aircraft debris, there was concern over underground gas lines or unexploded automobile fuel in the neighborhood vehicles.  At Ground Zero, the dangers to first responders were more numerous, from the dust clouds generated during the Towers’ collapse to subway tunnels and sewer pipes below the surface.  However, these two disasters were unique in many ways, but they represent the unknown hazards in any disaster.

But all transportation accidents beget their own hazards, whether the mode is Marine, Rail, Highway or Pipeline; for the sake of my articles, I stick with Aviation.  Each accident, whether General Aviation or Commercial, is fraught with dangers to first responders.  To support the discussion, let’s put our imaginary accident scene in an empty field, miles from civilization; the origins of the risks to human safety would be limited to the accident aircraft and the victims within.  These hazards could be classified under three categories: Technological, Biological and Unexpected.  It is for these reasons that first responders and accident investigators are hopefully well protected by HAZ suits.

Technological hazards are those attributed to the aircraft; they are limited to those perils that one can expect to find and are therefore, usually, avoidable.  As mentioned earlier in the introduction, fuel plays an important part.  Fuel not consumed by post-crash fires could seep into the ground, giving off noxious fumes that can be ingested through the lungs or burn unprotected eyes from excessive exposure.  Any fuel that seeps into clothing can cause second and third degree chemical burns if not removed right away.  The fuel tanks that are breached can be a constant supply of more fume, until the sections are removed from the scene and isolated.

Jagged sections of aluminum and steel can be dangerous, piercing through the protective clothing or just cutting the human’s – or cadaver dog’s – skin with deep lacerations; these injuries could introduce other chemicals, e.g. hydraulic fluids or engine oils, directly into the interior of the body.  Carcinogenic fumes from burning aircraft fluids can be ingested into the lungs and directly into the bloodstream.  Broken or shattered composite materials can splinter; this makes these plastic fairings a danger to anyone without gloves; they can also be breathed in, introducing composite splinters directly into the lungs where it is impossible to expel.

Biological hazards are those related to the victims.  There are many harmful ailments carried by everyday people; diseases that, by themselves, are only limited to the host carrying them.  Since no one considers the worst, even the most careful carrier of, e.g. the Human Immunodeficiency Virus and Acquired Immune Deficiency Syndrome (HIV/AIDS) virus can end up being the victim of an aircraft accident.  Airborne Pathogens can be present at the smallest accident scene or a major accident scene.  Many that can survive the accident for hours, are a danger to first responders, e.g. medical personnel, local law enforcement or the farmer whose field the plane crashed in.  These people, who may come in contact with body parts, the victim’s seat or grasses near the accident site can be infected.  Since accidents often generate tremendous forces, the pathogens can be carried by the air or explosion for great distances.

Unexpected hazards are those that the most knowledgeable of first responders may not expect, e.g. Depleted Uranium (DU).  Though used in small quantities, DU or other ‘heavy’ metals are found in major airliners in places that no one would look; they are used as counterweights or balance weights.  Why?  Because of the amount needed for the job required.

Every airliner has primary flight controls (PFC): Ailerons, Elevators and Rudders.  When viewed from the side, each of these PFC airfoils resembles a teardrop: the rounded end, or leading edge (LE), is mounted forward in the direction of flight; the aft end tapers to a knife’s edge; this thinner end is called the trailing edge (TE).  Where the PFC swivels is the pivot point; it is only inches from the LE, yet several feet from the TE; this is because a majority of the PFC’s TE is used to ‘control’ the flow of air while the LE allows for swiveling inside a fairing in the wing, vertical or horizontal stabilizer.  One other caveat: these PFCs must be perfectly balanced or they will cause damaging vibrations, flutter or worse, e.g. departure of the flight control, altogether.  Every PFC must balance at the pivot point; the LE and TE must be in equilibrium.

Enter depleted uranium; DU is so dense that its weight to area ratio is very high; you only need a small amount to get the weight needed for balancing.  For instance, a block of depleted uranium 6 inches X 2 inches X 8 inches (96 square inches) can weigh close to two hundred pounds.  This smaller size can allow the PFC to swivel with less drag caused by an overly large counterweight.

Although enclosed and sealed in a lead casing, depleted uranium has been known to break down physically.  Back in 1990, my co-mechanic and I removed a counterweight off the upper rudder of a DC-10 for X-ray inspection of the attach bolts.  Although we were careful not to breach the lead casing, the bolts had already been damaged by contact with the DU, which had penetrated the casing and acted on three of the four attach bolts.  There was considerable danger from exposure.  Furthermore, the lead casing’s physical integrity had broken down, resulting in uranium ‘dust’, which could be inhaled or trapped in the oils of one’s skin.

This is the Unexpected hazard: exposure to the counterweights.  The casing doesn’t have to be compromised from time; instead it could be damaged from impact forces; the counterweight could be thrown free from the aircraft, the lead casing shell creased from collision with the ground … or something.  Oh, come on, you didn’t really think Indiana Jones actually survived a nuclear explosion hiding in a lead-lined refrigerator, did you?

It’s good that Hollywood creates ‘realities’ where stories, like Cast Away or Kingdom of the Crystal Skull, can be told.  If their desperate for ideas, I have two novels they can read, if they’re interested … just saying.  But I have always found that there is nothing Hollywood can dream up that is scarier than the non-fictional reality … of Reality.

Aircraft Accidents and Lessons Unlearned VI: Eastern 401

There is an old Monty Python skit called Déjà vu; it is where comedian Michael Palin relives a moment repeatedly, e.g. the phone rings with the same message, a glass of water is repeatedly placed in front of him to drink and he runs to Terry Jones for help over and over again.  It’s a very funny skit; coincidentally it was taped around the same time as the accident referenced in this article.  The irony is that the aviation industry’s dealings with Déjà vu aren’t funny; they can be tragic as when we notice something that should have been remedied, but wasn’t.

The reason I do this series of Lessons Unlearned is to analyze recent accidents, find the missing pieces and make a teachable moment out of it.  This week I will reevaluate an accident that was so long ago that those in the Aviation Industry at the time are either long retired or deceased; that this article shouldn’t be called Lessons Unlearned, but Lessons Forgotten, or perhaps, more appropriately: Lessons Never Experienced.  In this case, I will explore an accident from decades past and try to explain why the aviation industry, both private and commercial, is doomed to repeat the same fatal mistakes made over forty years ago.

Eastern Airlines, flight 401, an L-1011, tail number N310EA, crashed in the Florida Everglades on December 29, 1972.  It is listed under National Transportation Safety Board (NTSB) report AAR-73-14.  Ninety-four passengers and five flight crewmembers – including all three pilots – were killed.  This accident is heartrending in that it was absolutely preventable; the flight crew, the aircraft and the weather were all without issue; however, the aircraft was, to put it bluntly, flown into the ground.

And in these facts alone, my point is that: the most tragic issue of this accident was in its simplicity.  No mechanic mis-rigged a flight control; an air traffic controller didn’t read back an incorrect altitude; a storm cell didn’t produce a sudden wind shear event.  Instead, three highly-trained and qualified pilots allowed a mechanically-sound aircraft to fly into the scene of the accident.  Eastern 401 was futility at its finest; it is also a WARNING: If things don’t change in the Aviation Industry, there will be numerous replays of this accident’s circumstances, some with similar endings.

Eastern 401 was a normal JFK to Miami flight; a well-trained flight crew, the aircraft in an airworthy condition.  During a standard approach into Miami airport, the crew diverted from the landing cycle due to a nose landing gear (NLG) position light refusing to illuminate Green, aka Gear Down and Locked.  The aircraft climbed to 2000 feet and, while seemingly on Autopilot, circled west of the airport to allow the crew time to ascertain if the NLG was, indeed, Down and Locked.

Two problems occurred during this basic maneuver.  The first: for four long minutes, the flight crew became obsessed with whether the NLG light was bad or that the NLG had not extended; this fixation kept both pilots from monitoring the instruments, allowing the aircraft to casually fly into the terrain.  The second: the flight crew was unfamiliar with the disengagement procedures of the L-1011’s Autopilot system; they unknowingly disconnected the Autopilot’s Altitude Hold function that was to keep them at two-thousand feet; they were also unaware that an aural warning announced that the aircraft exceeded a 250-foot drop in altitude.

The pilots did do some things right, e.g. the Captain sent the Second Officer to verify through the sight glass that the visual vortices – the markings on the NLG – showed the NLG as Down and Locked.  However, there were two serious lapses here that cannot be understated:

  1. The crew diverted attention away from the flight, altogether, and,
  2. The flight crew did not understand how the Autopilot worked … and how it didn’t work.

The Captain and First Officer were not just preoccupied with the NLG light, they were fixated to the exclusion of everything else going on during an active flight.  The L-1011’s gear position lights are on the front panel – just right of center – below the landing gear handle.  Focusing attention on this position light, the pilots could not observe the flight status instruments, unless peripherally.  The landing gear lights are also located below the glareshield, a ‘shelf’ that prevents instrument sun glare; this obstructed any view outside the forward windscreen.  On the descent into the ground, the crew could have also hit a lighted radio tower or other aircraft.

I’ve flown in the cockpit of a B727 when the left main gear Down and Locked light did not illuminate.  The Captain called for a ‘go-around’, aborting the landing to fly the pattern around the airport.  The flight crew then went through their procedures to assure Down and Locked, maintaining 100% awareness of the aircraft to its surroundings.  My flight crew prioritized; they were organized and they were in control.

However, just as important to me is point #2: the flight crew did not understand how the Autopilot worked … and how it didn’t work.  This is where the Aviation Industry is destined to fail over and over again … and has.  It is why I don’t fly anymore.  Warning the Industry of this uncomfortable fact is akin to being in a really boring public service announcement that everyone fast forwards through on their DVR.

I’m not suggesting that pilots know every rivet or hydraulic line.  When conducting enroute surveillance for the Federal Aviation Administration (FAA) or accident investigations for the NTSB, it has become painfully obvious that pilots and technicians are becoming complacent with the aircraft they work on.

Either Eastern 401’s Captain or First Officer accidentally turned off the Autopilot’s Altitude Hold function by bumping the control column, presumably when they were leaning over to change the NLG light bulb; they obviously didn’t know about this L-1011 quirk.  Again, so simple; and yet, so fatal.  If they weren’t so trusting of the technology; if they knew the aircraft a little better, the pilots may have been more attentive to Eastern 401’s flight status.

While conducting FAA enroute inspections, I discovered that many air carriers require pilots to ‘fly the computer’ more often; the reason is that the computer flies more economically, e.g. trimming the aircraft faster and more efficiently than the pilots can; this means money saved in fuel costs per flight.  But by relying on the computer, the pilots become too inefficient themselves, putting too much control and dependence on computer control, pilots’ skills atrophy from non-use.  Mechanics’ troubleshooting proficiencies become non-existent when they defer problem-solving to the aircraft computer’s capability to analyze itself.

Asiana flight 214 crashed on approach to San Francisco airport due to the flight crew’s mismanagement of the initial approach.  A perfectly airworthy B777 aircraft crashed because the pilots couldn’t out think the technology designed to help them.  Colgan 9446 crashed off Yarmouth, Massachusetts, because the pilots’ talents could not see beyond the obvious: they kept trimming nose down instead of nose up because the switches were responding in reverse.  Air Midwest 5481’s pilots pushed against a mechanical stop, an immovable object; trying to force something that could not be forced; not to be glib, but they were Pushing against a door designed to Pull open.  They wasted precious seconds on a futile problem they did not understand as opposed to running any other options.  The Captain’s last words, “Push down,” and “Push the nose down.”

Hey, Aviation Industry, it’s coming: Déjà vu.  And unlike a comedy sketch from the 1970s, this time it will not be funny.