What can programmers learn from pilots?

A talk I gave at PyCon US 2015

Transcript

1. Andrew Godwin @andrewgodwin
   Programmers
   LEARN FROM
   WHAT CAN
   Pilots?
   

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2. Andrew Godwin
   Hi, I'm
   Author of 1.7 Django & South migrations
   Senior Software Engineer at
   Really likes cheese
   FAA & EASA PPL, working on IR
   

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3. flickr.com/photos/russss/16735398019/
   

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4. Learning about aviation
   Applying lessons to coding
   1
   2
   

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5. Commercial flying is very safe
   AIRLINES
   GA
   0.2
   11.2
   CARS/TRUCKS 0.53
   MOTORCYCLES 15.6
   Source: 2005 Nall report, 2004 NHTSA stats, 1991-2000 FAA stats, 40mph avg. road speed
   (fatal accidents per million hours)
   General aviation is still not bad
   

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6. Pilot
   Source: 2005 Nall report
   Mechanical
   Other
   76%
   16%
   9%
   GA
   ACCIDENT
   CAUSES
   

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7. COMMON CAUSES
   Controlled flight into terrain (CFIT)
   Disorientation in clouds (VFR in IMC)
   Bad decision making (get-there-itis)
   

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8. WHY DO I KNOW THIS?
   Detailed investigation of every accident
   

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9. HOW DOES IT HELP US?
   Let's look at common problems
   

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10. Soft Failure
    Explicit disengage signals
    Covering inaccurate instruments
    Replacing parts at first sign of issues
    

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11. Soft Failure
    Crash hard on any serious error
    Redundancy, not single system reliability
    Freedom to get rid of servers whenever
    

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12. Noisy Warnings
    Limited number of warning sounds
    Clear, unambiguous text & speech
    No constant low-level warnings
    

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13. Noisy Warnings
    Don't email/notify on every tiny error
    Choose 5 top errors, solve them first
    If you ignore it for a week, delete the warning
    

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14. Poor Testing
    Every part tested to destruction
    Well known statistical limits
    Knowing when, not if, things fail
    

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15. Image: © Boeing 2010
    

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16. Poor Testing
    Test latency, memory issues, dodgy
    network and other unusual things
    Interactions are as important as
    individual units
    

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17. Automation Reliance
    Tested without autopilot/instruments
    Plane usually advises, rarely controls
    Easy to see what's happening and why
    

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18. flickr.com/photos/wkharmon/4631001766
    

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19. Automation Reliance
    Don't rely on magical automatic failover
    Regularly practice manual recovery steps
    Know what your systems are doing
    

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20. People Reliance
    Checklists for everything
    Warnings built around common assumptions
    Reduce workload at critical times
    

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22. People Reliance
    Checklists for releases/testing/onboarding
    Automate common tasks
    Reduce workload at critical times
    

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23. Bad Priorities
    Aviate, Navigate, Communicate
    Minimum Equipment Lists
    Mayday priority
    

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24. Minimum Equipment Quiz
    Passenger video screens
    Lavatory ashtrays
    Air conditioning
    Fuel recepticle caps
    Seatbelt signs
    Weather radar
    

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25. Minimum Equipment Quiz
    Passenger video screens
    Lavatory ashtrays
    Air conditioning
    Fuel recepticle caps
    Seatbelt signs
    Weather radar
    

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26. Margaret Hamilton
    

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27. Bad Priorities
    What are your critical features?
    What can you do without?
    Know what you want to fix first and test most
    

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28. Unclear Responsibility
    Single person always in command
    Others are always listened to
    Clear, concise communication
    

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29. Unclear Responsibility
    Single person makes key decisions
    Others are always listened to
    Clear specifications and expectations
    

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30. Blame Culture
    There is never a single cause of an accident
    Individual problems identified and addressed
    Blaming someone solves nothing
    

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31. Blame Culture
    There is never a single cause of a problem
    Work back and find all of the bad factors
    Blaming people makes things worse
    

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32. Deadlines
    Always carry extra fuel
    Always have an alternate
    Land safely rather than at the destination
    

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33. Deadlines
    Don't schedule everyone at maximum
    Always expect unknown problems
    Ship good code rather than to a deadline
    

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34. Takeaways
    

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35. Checklists
    First step before automation
    

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36. Filter unimportant errors
    Keep ignoring it? It's not important.
    

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37. Pick your key features
    Don't worry about breaking minor stuff
    

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38. Reward good decisions
    It's often not the people staying late
    

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39. Ops are like pilots
    Boredom punctuated by moments of terror
    

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40. Thanks.
    Andrew Godwin
    @andrewgodwin
    eventbrite.com/jobs
    

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