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Wednesday, July 15, 2015

Aged To Perfection



Today is a pretty special day. Exactly 61 years ago, in Seattle, was the first flight of Dash-80, the prototype of the Boeing 707.   The 707 is one of the most important and iconic airplanes ever built. She had a great career, but things change and she became out dated and no longer relevant.

I retired from the flight deck the first of the month and since I am no longer flying, I have decided to retire the blog as well. This will be my last post on Flying The Backside.   It’s time for someone else, someone younger, more relevant to write about human factors in aviation. These topics are the same as 40 years ago when I started, but yet they seem different.  I can’t really relate to them now.  Flying is so much more complicated than it used to be.  I would find it very challenging to be a young pilot today trying to figure out what I should know and what’s really important.  Stick and rudder skills have been replaced with alpha-numeric key strokes.  Decision-making has been eliminated and replaced with rote compliance.  It is no longer necessary to know why we, as pilots, do what we do.  Just follow the recipe.

It wasn’t always this way.  The transition from props to jets was hard, but nothing like this.  It was airplanes to airplanes, not airplanes to the App Store.

Today is also my wife’s birthday.  She too was born in Seattle, Washington on July 15th, 1954.  Dash-80 has not flown in many years.  My wife, however, has never been more attractive or vibrant.  She supported me and sustained me throughout my career and is now ready to embark with me on a new adventure, traveling in our RV.  We look forward to rediscovering America and each other.


Thanks to everyone who read, subscribed or commented and I look forward to sharing my experiences from the road.  Until then, fly safe and watch out for each other.

Wednesday, June 3, 2015

Stoplights





Ok, so I am in the last month of my career.  I have been asked what are the best and worst parts.  The best are the memories of incredible people and places.  The worst are the missed opportunities.  Providence gives us opportunities and it’s a sin to waste them. As the heir of the greatest generation my contemporaries and I were bequeathed almost unlimited opportunity in aviation.  We did a lot of good things, but we could have done better.  We could have more effectively established the partnership between threat identification and mitigation and standardized operating policy.   I regret the part I played in that.  Did we leave the industry with the more opportunities or are they just bigger challenges.  I am not sure there is a difference, but I am sure that we have not adequately prepared the next generation to understand and meet them.  We have taught them to obey rather than think.

Personally, as I reflect on my career, I have been trying to access what I have learned from four decades of flying airplanes for a living.   It all comes down to this.  We have only been marginally successful at exploiting technology in modern aviation. We have been mostly ineffective in this area because we now value data (information) over decisions.  Since technology is vastly better at information acquisition and management than humans, we are now working for the machines.  We are now the robots.  We don’t use technology to decide what to do, we do what the machines tell us to do.

This all became clear the other day when our family was in the car at an intersection when the car in from of us made a left turn with a red arrow displayed on the traffic light.  The turn was made after the oncoming traffic had cleared and was safe in every way except that there was a red light (arrow).  My family all thought the maneuver was very dangerous.  I asked them why and our discussion was very revealing. 

Just because the light is green is it safe?  Is it always unsafe when the light is red?  Can we trust that the light will always achieve the desired outcome?   Does the stoplight replace decision or just display information?  Can a display of information replace human analysis of the situation?  I believe we would all say no, however what do we practice?  Will the auto pilot always level the airplane at the right altitude?  How do we know it's the right altitude?  Technology can supply information, and lots of it, but only humans can provide the context.  Automation can perform complicated tasks accurately and efficiently, but in what combination.  Just yesterday local teenager was killed when his car rear-ended a semi truck while he was texting.  Is the answer to texting in the car collision avoidance technology?  Really?

Moreover, aren’t policy and procedure just the written version of stoplights.  Volumes are written that say do this don’t do that.  Go this way, don’t go that way.  Like the stoplight there is only binary instruction.  Red STOP and green GO is all we get and we must intuit the context.  Unfortunately, the “why” behind policy is usually much more difficult to derive than that of the traffic signal.  Often the “why” is simply unknown to the user.  Standardized verbiage at specific altitudes are a great example of this.  Compliance trumps understanding.

Machines and their instruction manuals are simply tools.  Tools are what have allowed man to achieve dominion over all other creatures on the planet.  Since the dawn of humankind, man has been using tools to improve their lives, albeit, not without significant collateral damage.  The proliferation of highly sophisticated tools, i.e. technology, is the greatest threat future generations of aviators will face.  This threat exists because of the fundamental flaw of machines, binary decision making.  It is all “1’s and 0’s”, a vast array of little digital stoplights.  Until we move from digital to the next higher level of technology these tools will all lack the uniquely human concept of “maybe”.  Judgment, or the resolution of “maybe” is where humans out perform machines.  A human, unless he cheats, cannot beat the computer at chess because it is computation.  There are a finite number of moves.  Knowing how to write the algorithm for the computer does not make the programmer a chess player either.  It just means he is good at writing code.  The computer is making the “decisions”.  However, when randomness in introduced into a game such as dice with backgammon or cards with poker the computer doesn’t do as well.  The computer doesn’t know what will happen, only what might happen.  The infinite number of “maybes” in the real world makes the roll of a dice seem almost boring. 

The concept of maybe is the inscrutable link between the one and the zero.   It is the fork in the road.  The choices we make are important and the factors in the real world are often unpredictable and random.  This is the difference between risk assessment and threat management.  Risk assessment is the statistical product of probability and severity.  Risk can tell you what the probability of an event is and how bad it can be.  Pretty cut and dried.  Threat management, however, is the process we use to hopefully adjust (lower) those factors (probability and severity).  The environment that is aviation is not predictable, therefore, we cannot totally abdicate the decision making process to technology.   We must use machines and their instruction manuals for what they are, tools. They are not and should not be used as a substitute for decision making.

The 787 Dreamliner that I am about to leave behind is the most sophisticated airliner ever built, but it is still just an obedient, but fallible machine that will only do what it has or has not been programmed to do.  Flying the 787 or any other modern airliner is not playing chess with a fixed number of choices.   We are operating in real time in a capricious and unforgivable environment that can only be tamed by the magnificence of the human brain.  We have turned the corner.  There are no human pilots that can fly the modern airplane as accurately and efficiently as it can fly itself.   How will we teach tomorrows aviators to effectively use these incredible machines?   Is the future of aviation really just the deployment of more and better stoplights?  I believe we could have done better.

Monday, January 26, 2015

WHY DO WE DO WHAT WE DO?


Is it important for pilots to know why they do what they do?  I thinks so, but some might disagree.  I think we should talk about it.

I have stated before that my desire for this blog is to facilitate a dialog among aviation professionals.  I hope this post will initiate such a discussion. 

Standard Operating Policy (SOP) is the hallmark of private and commercial aviation.  It describes in detail the steps that are to be taken to accomplish a specific action or task. Is it relevant or required to know what the SOP is supposed to accomplish or why it is important?  Must SOP compliance accomplish a specific objective or may compliance be its own objective with no other purpose?

I would like for readers to “weigh in” on this subject based on a specific example.  Therefore, I pose these questions….

As a single pilot or a pilot in command of a multi crew aircraft, what is my responsibility in the following scenario?   I am landing on a runway that I have landed on many times before.  The aircraft is at a normal landing weight and I have landed at this weight many times before. There are no weather considerations and the wind is less than 10mph.  The runway is clear and dry.

Must I compute landing distance for this landing?  If the answer is no, why is it not required?  If the answer is yes, why is it mandatory?  If the only reason to obtain landing data is because it is included in SOP is that a valid reason? Is computing distance the same as evaluating landing performance?

Finally, should a single SOP be written for all conditions or should SOP be based on the relevant conditions?

Sunday, July 13, 2014

Asiana 214 and NTSB Credibility


The National Transportation and Safety Board of the United States, NTSB, recently released it’s findings on the crash of AsianasFlight 214, which crashed on July 6, 2013 at San Francisco International Airport (SFO).  All professional aviators and their instructors as well as air traffic control specialists should read and study the report.  The information in it describes the enormous potential for and realization of unimagined failures that always exist in the complex relationship between humans and the machines they control. 

There is no question that the crew of Asiana 214 (humans) failed to effectively manage their Boeing 777 in the final moments of the flight.  The NTSB detailed the operational errors of the crew, the design flaws of the flight guidance system and some relevant issues related to their training.  The report also highlights numerous other contributory factors, but uncharacteristically for the NTSB, missed a very obvious one, air traffic control.  The NTSB has been the worlds “gold standard” in aviation accident investigation for decades.  Unfortunately, it seems the gold might have lost some of its glitter.


The probable cause of Asiana 214 focused on human failures, primarily by the crew and secondarily by designers and trainers, which were thoroughly examined in the investigation.  However, there are other human components of this story that should also be examined for their role in this fatal accident.   Specifically overlooked was the environment in which the flight operated.  The machine was a Boeing 777. The environment was the airspace near SFO. The humans are the engineers, instructors, air traffic controllers and pilots who design, train and operate them. The NTSB report on Asiana 214 surprisingly describes the contributory role of the aircraft and each of these other elements except air traffic control.  How can this report have such an obvious omission?  This is very perplexing.  Was it just a huge oversight or an intentional exclusion?   In light of the fact that there was speculation by the Board on other contributing factors, this oversight is even more astonishing. 

Currently, at large metropolitan airports where the air traffic volume is heavy, a flight crewsrole has evolved into that of a facilitator between air traffic control instructions and the airliners flight guidance system rather than that of aviator.  Like all pilots flying modern airplanes into highly controlled airports, including SFO, the crew of Asiana 214 was tasked with converting the commands (not suggestions) of ATC into a desired flight path and energy state by programming the aircrafts flight guidance system.  The Boeing 777 is both designed and its pilots trained to operate it with reference to the flight guidance system.  Desired parameters are entered and the computed information is shown to the pilots by reference to the flight directors on the primary flight display (PFD) or heads up display (HUD).  The pilots follow the flight director commands manually or by engaging the autopilot.  The flight directors are turned off in flight on only very rare occasions.

Because the Asiana crew was ineffective applying their approach clearance to the flight guidance system, their workload increased dramatically.  ATC’s instruction to maintain a high speed longer than normal increased task saturation as well.  A late landing clearance by SFO tower provided an additional distraction diverting the crew’s attention away from subtle flight guidance information in the final seconds before the crash.   

Although there are many aspects to the air traffic control handling of Asiana 214, I will limit the discussion of ATCs contributory role to the time period after the crew received their approach clearance.

From the NTSB history of the flight (italics): 


"According to recorded information, NORCAL stated “Asiana 214 heavy, San Francisco airport 9 to 10 oclock, one seven miles, do you have it in sight?” The flight responded they had the field in sight and NORCAL cleared them to fly a visual approach to runway 28L on an assigned heading of 310° to intercept final approach. At a point approximately 14 NM5 from the airport NORCAL instructed the flight to maintain 180 kts until 5 NM from the airport."


This command by ATC, as well as the inoperative electronic glide slope, set up a series of events that facilitated the crash.  It is not certain, but clearly reasonable to infer that if the crew had been allowed to slow the aircraft at their discretion, or if there had been an operable electronic glide slope, the unintended consequences of autothrottle “HOLD” would have occurred at a higher altitude or not at all.  How can the NTSB omit these relevant facts?

The NTSB found that the flight could have been completed successfully without the electronic glide slope.  That statement is not particularly probative since it is made without context. As the Asiana pilots pointed out in their submission, a Flight Safety Foundation (FSF) report on approach and landing accidents (ALA) stated that 75% of flights did not use or have a precision approach aid available.   The FSF further states that the accident risk is 5 times greater for commercial aircraft flying non-precision approaches.

In the hearings the NTSB conducted on the human factors of this accident, Dr.s Sarter and Abbott and Captain McKenney all testified to the interrelationships between parts of a safety system. As the “swiss cheese metaphor” for safety systems shows, the slices are only effective when used in combination.  Removal of one slice may or may not be significant depending on the make up of the other slices.  Why does one plane crash in the same conditions that allow many others to be successful?  That is why the role of ATC in this accident cannot just be brushed as inconsequential.   These are exactly the issues the NTSB is tasked with considering.


“The trainee captain stated that after arming and intercepting the localizer he set the DUYET intersection crossing altitude of 1,800 ft. MSL in the mode control panel (MCP) altitude window and began using the AFDS vertical speed (VS) mode to descend at 1000 feet per minute (FPM). The IP stated the arc on the navigation display (ND) showed they would be high at DUYET. The observer stated he thought they were a little higher than the normal profile when they were cleared for the approach, and they extended the landing gear earlier than normal because they needed to get down. The trainee captain set the command airspeed bug to 172 kts, and acknowledged when the observer commented this was below the assigned 180 kts.”


This emphasizes the fact that the 180 knot restriction was increasing the crew's task saturation by complicating energy management solutions. 

At the prompting of the IP, the trainee captain increased the command vertical speed to 1,500 FPM. The trainee captain commanded the flaps be set to 20° and requested the IP to reset the command altitude from 1,800 ft. to 3,000 ft., the missed approach altitude, as the flight approached 2,000 ft. MSL.

According to recorded data, at 1,600 ft. MSL the AFDS pitch mode changed to FLCH SPD, the throttles began to increase power, and the airplane pitch attitude began to increase; this was followed by autopilot disconnect and shortly thereafter a reduction in the thrust levers to the idle position, followed by a change of the autothrottle mode from THRUST to HOLD. The trainee captain stated he considered pressing the FLCH pushbutton to obtain a higher descent rate but he could not recall what he did for sure. He disconnected the autopilot and called out “manual flight.” None of the three pilots could recall the autothrottle status displayed on the flight mode annunciator (FMA). The IP stated he set the command airspeed to the approach speed of 137 kts. and turned both flight director (FD) switches off and then turned the right FD switch back on. Recorded data showed the left FD switch was turned off but the right FD switch remained on.


Pre selecting the missed approach altitude is common practice by B777 crews.  However, setting an altitude above the aircraft without the flight guidance capturing and maintaining either an altitude or glide slope caused the autopilot to initiate a climb. The pilot naturally and appropriately disconnected the autopilot and manually flew the aircraft. Unfortunately, that unusual set of circumstances caused the auto throttle mode to remain in "HOLD" and not respond to the commanded speed as the crew expected. 


“The trainee captain called for the flaps to be set to 30°, and after a delay due to the airspeed being in excess of the flap limit speed of 170 kts. the IP placed the flaps to 30°.”



Because ATC instructed Asiana 214 to maintain 180 knots until 5 miles, they would be 10 knots above the limit speed for flaps 30° and 43 knots above their target approach airspeed at approximately 1500AGL (3 degree glide path).  Without an electronic glideslope or a VNAV PATH, this complicated programming of the flight guidance system.  At 1000’ AGL, their mindset would likely have been slowing the airplane down quickly as they descended and closed on the runway.  The power needed to be reduced to idle to get below the limit speed for flaps 30 (170 knots) as well as slowing to the target approach speed of 137 knots.  This maneuver, set up by ATC requirements was clearly contributory to the accident.


Flight 214 was handed off to, but not acknowledged by, San Francisco Tower.  In combination with the ATC imposed energy management complication, lack of electronic glide slope and flight guidance mode confusion, this was another significant distraction. 


“The instructor pilot stated he saw 2 red and 2 white precision approach path indicator (PAPI) lights at 1,000 ft. MSL and speed was a little high. The observer saw the descent rate on the vertical speed indicator was in excess of 1,000 FPM as the flight descended through 1,000 ft. MSL, and he called out “sink rate” several times. The IP stated he heard this callout but they were still high and the descent rate was only 1,000 to 1,100 FPM.”

 
Slightly above the glide path and slowing, the trainee captain manually flew the aircraft toward what he thought would be a stable approach at 500’.   Unaware of the significance of the autothrottle “HOLD” mode, the aircraft slowed toward target speed.  Still not cleared to land and below 1000the crew once again queried San Francisco Tower and received landing clearance 9 seconds later.  The late prompted landing clearance was an ATC distraction that diverted the crews attention at a very critical time.    

The aircraft was on glide path with the idle power as it descended toward 500’.  At about 500the aircraft began to drift below the PAPI (glidepath).   As the pilot began to adjust the descent with pitch, the aircraft quickly slowed well below target speed.  By the time the crew was alerted, noticed the low speed and initiated a go around it was too late.

In any accident, there are many factors that intersect to create the causal conditions.  Failure to consider all of them results in an incomplete and ineffective investigation. The relevance air traffic control resources, procedures and practices might have had on this accident is not the depth of analysis we have come to expect from the NTSB.

It would be extremely naive to believe ineffective or improper use of the flight guidance system to comply with air traffic control instructions only affects a few crews.  Recognition by the NTSB that air traffic control practices have a profound impact on how crews operate the flight guidance systems of modern airliners would be more consistent with their role in aviation safety. 

Since the report on Asiana 214 was prepared under his leadership, I would hope that Acting NTSB Chairman Hart would be given the opportunity to give his perspective on this controversy during his confirmation process.