Medicine Grand Rounds at Stanford

Yesterday I gave a Grand Rounds presentation at Stanford Med School. My title was

Craft, Standardization and Automation: Powerful yet Perilous Paradigms for Control when Lives are at Stake

Most of my talk was about the adoption of procedures (checklists) by US military aviation, during and after WW II. It has close analogies to the situation of health-care today.  Here is my short presentation.  A much longer presentation, with more examples but without discussion of medicine, is here.

Initially, I was concerned that my topic might seem too esoteric for Stanford’s medical faculty. However, their Medical Grand Rounds program covers a lot of ground. My topic was only 1.5 standard deviations away from the mean.

For more of my research on flying paradigms and how technologies evolve from crafts to sciences, please see this page.


How flying changed from a craft to a science: Chapter 1 available

I have just uploaded Chapter 1 of my book manuscript. It summarizes four revolutionary changes in how people flew. It outlines some themes of the full book, including People and Work and Is Science Inevitable?. And of course it includes a few gripping tales of accidents averted – or not.

Commercial aviation today is very safe and scientific. But it wasn’t always. Please send comments, anything from typos to critiques.

Over August I will put up some photographs and key tables from the full book.

Some flying still relies on personal skill

For some reason I take comfort in knowing that there are still aviation jobs that have a high degree of craft (art). According to this article, a lot of the training is by apprenticeship (copiloting), which was the only way to learn flying in the 1930s.

Most of my aviation research emphasizes how craft skills are becoming less important. And indeed there is also a lot of procedural science in mosquito spraying. But in a variety of high-variety, high-risk aviation, expertise is still key. Other examples are bush flying and low-altitude military flying.

Source: Expert Pilots Keep Disease-Carrying Mosquitoes in Check | Flying Magazine


Not your grandfather’s crop duster!

Drones Hunt Down Poachers in South Africa | Flying Magazine

The Lindbergh Foundation’s Air Shepherd initiative uses drones to catch poachers in South Africa.

My comment: Flying at night, up to 40km away, is technically difficult. But smart autopilots, using GPS and accelerometers, mean that the operators (pilots) don’t have to do hands-on flying except landing and takeoff.  Probably every component in the system except the ground vehicles is hobbyist level, although some of the specialized long-range radio gear might need to be hand built.  Nothing from aerospace companies.  Battery powered, so essentially noiseless. Also, the aircraft itself is the cheapest part of the system.

The article mentions flights of “up to 4 hours.” That is a very long duration, and would require lots of batteries. 2 hours or even less sounds more realistic. Efficient cruising speed is probably is probably around 40 kph (25 mph). If anyone finds other discussions of this project, please let me know.

Source: Drones Hunt Down Poachers in South Africa | Flying Magazine

Airbus design again contributes to crash

One contributor to the A320 crash off Brazil in 2009 (Air France 447) was that the two pilots were making opposite inputs on their control sticks. The aircraft was in a stall, and therefore it was crucial to push the nose down, to regain airspeed. The instinctive human reaction (of untrained people) is to pull the nose up, since the airplane is falling. To oversimplify a long sequence of events drastically, pilot made the correct move, but the other pilot apparently panicked, and pulled back on his control stick. He continued to do this as they fell from 40,000 feet all the way to the Atlantic Ocean.

A new accident report says that the same thing happened in the crash of an  Indonesia AirAsia Airbus A320, flight QZ8501, last year.

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How often do pilots skip checklist steps?

Board blames fatal overrun on pilot error.
Source: NTSB Issues Bedford Gulfstream IV Crash Report | Flying Magazine

Checklists were a major innovation in flying, and are now being pushed in health care. But as I research this, it’s clear that although pilots all swear by them, use is less than 100%. Perhaps less than 99% – and a 1% error rate is very high when there are hundreds of items on a flight.

It’s very hard to know the real number. But the pilots in this crash, both very experienced, did pre-takeoff control checks for less than 10% of their flights!

Data from a recorder installed in the airplane showed that in the previous 176 takeoffs, full flight control checks as called for on the GIV’s checklist were carried out only twice and partial checks only 16 times. The pilots on the evening of the accident skipped the flight control check, which might have revealed to them that the gust lock mechanism was still engaged.

This particular item – forgetting to unlock the “gust locks” – has been killing pilots since the first gust locks. Famous examples in the 1930s were the prototype B-17, and the head of the German Air Force. (Both discussed in my forthcoming chapter on standard procedures in aviation.)
Gulfstream IV jet with six on board - crashed and burned after failed takeoff.

Latency in UAV operation (geeky)

An interesting question about how much latency is acceptable for UAV operation.  My answer, based partly on my radio control flying experience, is that it depends heavily on the context. 200 milliseconds is too long for stunt flying, but not a problem for flying larger UAVs at higher altitudes. The operator has to “dial in” their reflexes to the situation, just as sailors do with different sizes of sailboats.  Here’s an example where low latency is essential:  

A seeming paradox is that longer latencies are acceptable only at higher Stages of Control. (See my draft book for discussion of this concept.)  At the high end (what I call Computer Integrated Flying), if enough knowledge is embodied in the aircraft, the operator can pull back entirely from flying, and switch to “commanding” the aircraft.

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