Bruce Landsberg at the AOPA Air Safety Foundation writes in "The FAA's Small Aircraft Directorate...looked at more than 1,700 stall/spin accidents dating back to 1973 and concluded that 93 percent of those airplanes were at or below pattern altitude — too low for spin recovery. ... What would happen if the departure from controlled flight, the stall, was made more difficult [by changing aircraft design characteristics]. Would fewer accidents occur? If the stall is prevented, the spin can't happen. More important, how many lives could be saved if the aircraft's stall characteristics were friendlier?"
Good question. In the same vein, we ask "What if the pilot were more aware of how close s/he was to an incipient stall?"
Alex Paterson is an Australian airline pilot. He writes in that "good [cockpit] design recognises that humans are fallible and are very poor at monitoring tasks (because monitoring is so boring) whereas a properly designed machine ... can be excellent at monitoring tasks."
On that subject..recently I was in my King Air demonstrating the AoA to a pilot with a lot of King Air time but new to my cockpit. He had recently passed a recurrent check but as it had been a long time since he flew King Airs, he was still a bit slow on the switchology (as anyone would be). Let's listen to him:
"The first time I flew the Legacy AoA device, I was in an unfamiliar cockpit downwind abeam the numbers, planning for two turns to landing on a short runway in gusty winds; I was intently focused outside at the runway numbers...when I heard “Boing! Getting Slow”. It got my full attention. My head swiveled right back to the airspeed indicator. Sure enough, I was slower than I had thought I was, but I was not even close to being at risk. The warning came early and it was helpful." That's from a Decathlon owner who flies acrobatics; he's a working CFII and a retired A/A767 Check Airman.
An EARLIER article, but very interesting:
Richard Aarons in "Business & Commercial Aviation", April 2006
(posted here by permission)
"Using Angle of Attack Indicators"
(This is a great article, posted mostly for your information, as these systems are far more complex and costly than the Legacy display we are using.)
Read also in Air Safety Week by Gary Williams. He began his flying carrier in the U.S. Navy, an institution which emphasizes flying by AoA. In the years since, Williams has accumulated what he proudly describes as 13,000 "incident and accident-free hours," 9,000 as a captain...
* "The AoA indicator does not have to be programmed. Once in the air, it doesn't care about the weight, angle of bank or flap configuration. Or the altitude. Or the temperature. All it displays is the one thing that makes the aircraft stay in the air - the angle of airflow across the wing. The indicator has a little tick [or a donut] that shows maximum lift over drag (L/D). It is always available, so all one has to do is look at it to immediately analyze what is happening to the wing."
* "As a bonus it can be used in an engine-out situation to maintain best angle of climb or minimum angle of descent (also giving maximum range - handy when gliding should all engines quit). If the pitot system fails (ice, bugs, etc.), a quick glance can confirm a safe flight condition."
* "How about maximum endurance? That's kind of nice to have in holding..."
* "The airplane flies on AoA, not airspeed. Every flight operations manual has a page the gives the pilot pitch information in the event of a loss of airspeed indication. Flying the changing pitch required under those circumstances would be tough under the best of circumstances."
* ... the only thing missing is the AoA indicator. And training. How many AoA indicators would the cost of a single accident buy?" COPYRIGHT 2000 Access Intelligence, LLC COPYRIGHT 2008 Gale, Cengage Learning
Take a look at Bruce Landsberg's 2010 blog at AOPA Air Safety Institute on AoA; read lots of interesting reader comments on whether or not AoA is a useful tool.
Here's a really good AOPA Air Safety Foundation article
STALL/SPIN: ENTRY POINT FOR CRASH AND BURN? A brief clip:
Student pilots and ATPs are the least likely to stall/spin. Student pilots are, by far, the least likely to suffer stall/spin accidents, as a proportion of in the pilot population. Pilots holding FAA Airline Transport Pilot (ATP) certificates are also less likely to stall/spin.
That leaves pilots with FAA private and commercial pilot certificates in the "most likely to suffer fatal stall/spin accidents" category. In fact, commercial pilot certificate holders are by far most likely to show up in the stall/spin accident statistics, again based on the proportion of their representation in the pilot population.
An instructor on board is no guarantee. In reviewing 44 fatal stall/spin accidents from 1991 - 2000 and classified as instructional, ASF found that a shocking 91%(40) of them occurred during dual instruction, with only 9% (4) solo training flights. Of the fatal instructional accidents, 64.4% of them occurred during maneuvering, and 17.8% of them occurred during takeoff.
Take a look at the accident summaries.
More from Thomas P. Turner,
In his Dec 2010 to get maximum performance and avoid mishaps: "I benefited from the generosity of reader Charles Lloyd, a NetJets captain. He flew to Wichita in his Cessna 182J to give me some left-seat experience using the Alpha Systems angle of attack indicator. I quickly found using the AoA to be easier and vastly superior to flying by reference to the airspeed indicator—my lack of recent experience in Cessna 182s made maximum performance even easier for me using AoA. about my AoA experience, linking to some of Charles’ writings on the topic, exploring different displays and options, and maybe making you an AoA enthusiast too...in upcoming issues of ."
The FAA has a excellent Advisory Circular AC61-67C:
"Stall and Spin Awareness Training"
HUGELY IMPORTANT! ... RECENT NEWS! ... June 2015--in the , the FAA is making a big push to get AoA indicators installed in General Aviation aircraft.
In its extraordinarily helpful December 2011 FAA clarification letter, the FAA Small Aircraft Directorate explains that installation is a "minor alteration" on the vast majority of light general aviation aircraft.
Newly-published magazine articles, Spring & Summer 2011
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