KHAQQ TO ITASCA.  WE ARE ON THE LINE 157 337, WE WILL REPEAT MESSAGE. WE WILL REPEAT THIS ON 6210 KILOCYCLES. WAIT. WE ARE RUNNING ON LINE NORTH AND SOUTH.

Radiophone from Amelia Earhart received by USCG Itasca,
Howland 0^o48'07"N 176^o38'3"W 2013 GCT July 2, 1937

Her round-the-world flight ended tragically sometime after that last transmission on July 2, 1937.   Amelia Earhart had taken off in her Lockheed Electra 20 hours and 13 minutes earlier (0000 GCT) from Lae, New Guinea on an eastbound flight along the Equator for a distance of 2,556 miles to Howland Island.

Navigator for the estimated 18-hour flight, Fred Noonan would apply dead reckoning in the daylight, celestial navigation at night, and radio direction finding for homing on the island, but....

TIGHAR Earhart Project used by permission

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Please excuse me for dropping into the first person singular here. 

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As a pilot, I was bemused by Amelia Earhart's last sentence on the radio, "WE ARE RUNNING ON LINE NORTH AND SOUTH."  The maneuver is impossible, of course -- north or south but not both.  I heard it first in the 2009 film Amelia, starring Hilary Swank and Richard Gere.  Clearly, the screenwriters neglected to obtain the services of a script consultant with an elementary knowledge of aviation.  Such gaffes are common enough (Air Traffic Control, Radio Phraseology, Runway Numbers).  A quick check in Wikipedia, however, confirmed Earhart's exact words as set forth above. No longer bemused, I became puzzled.

Is there any doubt that the last flight of Amelia Earhart is the greatest aviation mystery in history?  Over a period of seven decades, hundreds of volumes have been publish on the subject along with uncountable articles offering speculations and analyses.  I use the term "Amelianna" to descibe the vast body of literature, although none of the 55 on-line dictionaries lists that coinage.  Yet.

The entry in Wikipedia really got me going.  A Bing search on "Amelia Earhart" turns up more than a million hits of every kind imaginable (biographical, encyclopedic, enthusiasts, and at least one I would never have imagined, The International Group for Historic Aircraft Recovery (TIGHAR -- pronounced “tiger”).  The TIGHAR website offers an immense resource entitled Ameliapedia, and the group also periodically charters archeological excursions to the island of Nikumaroro in search of artifacts, guided by Ric Gillespie, author of Finding Amelia: The True Story of the Earhart Disappearance. Fascinating. 

Oh well, I thought to myself, it wouldn't hurt to read just one more book on the subject.  I ordered Elgen and Marie Long's Amelia Earhart: The Mystery Solved.  That one volume took 25 years of research and covers the world flight and its tragic end with thoroughness and authoritative insights.  I have read it twice, some passages thrice. 

Puzzles with a Purpose is my garden. That's what I like to call it. One of its 'seed beds' is Puzzles in the Skies.  I began thinking up technical challenges alongside proposed explanations relevant to the Amelia Earhart mystery, starting with Landfall Navigating and Wages of Flight.

But wait, it was radio failure that caused the disaster in 1937.  So I got hold of Amelia Earhart's Radio by Paul Rafford, worldwide expert on the subject, an investigator who spent decades conducting interviews with contemporaneous radio technicians and other witnesses.  Rafford restored original radio equipment and even built a scale-model of the Lockheed Electra that took up his whole backyard to test antenna radiation patterns. 

Thus inspired, I drafted Simplexity Aloft and Gathering Range. The puzzle/solution literary genre is distinguished from other non-fiction works:  Each puzzle (énigme in French) creates suspense and engages readers -- I call them "solvers" -- in an active discovery process. 

There are many biographical tributes to Amelia Earhart, including, for example Susan Butler's East to the Dawn: The Life of Amelia Earhart.  The most extreme efforts devoted to Amelianna must have been those made by Ann Holtgren Pellegreno.  In 1967, she led a team of aviation enthusiasts in restoring and customizing a venerable Lockheed Electra then flying the thing all the way around the world to commemorate the 30th anniversary of the attempt by Amelia Earhart and Fred Noonan, producing an exciting chronicle, Amelia Earhart's World Flight: The Earhart Trail. And then there is Amelia Earhart's own Last Flight, which was poignantly completed by her husband George Putnam.  The abundance of literature about Amelia Earhart and her adventures, now filling a dedicated bookshelf in my office, meant one thing: that I needed to set some limits.

The round-the-world flight began on May 20, 1937.  I decided to exclude all incidents that occurred during those 43 days prior to July 2, 1937.  There is one exception: On the solution page of Gathering Range, solvers will find a surprisingly relevant incident and see why I was compelled to include it.

My studies of Amelianna turned up a few far-fetched distractions, for which I kept my Occam's Razor well stropped.  Whereas Dick Strippel's Amelia Earhart: The Myth and the Realities performs a valuable service for researchers, solvers are well advised to be skeptical of the intrigues postulated in such volumes as Amelia Earhart Lives by Joe Klass and Joseph Gervais, likewise Amelia Earhart Survived by Rollin Reineck.

Among the proposed solutions I am providing to solvers, at least two of them -- Here Comes the Sun and Live Reckoning -- are distinguished by their containing genuinely original discoveries.  Sophisticated solvers are invited to confirm or challenge them and submit comments here for an epilogue.

Meanwhile, the question, "Which way, Amelia?" returns again and again to my mind.

 
A total of ten entries, including this one, have been published on the web in the past as works-in-process.  Solvers near and far have made comments.  One person, Ian Mann, who lives in Goulburn NSW, has written hundreds of messages, generously sharing a wealth of historical materials collected over decades.  Even more valuable has been Ian's introductions of noted authorities in Amelianna, including Gary LaPook, Paul Rafford, Douglas Westfall.  Thus, an ad-hoc group of enthusiasts has joined me on this project since 2009, the 72^nd anniversary of the flight.

Occasionally I get the feeling that, for scholars in the Amelianna culture, prolonging mystification trumps reasoned revelation -- that they prefer being confounded by puzzles more than actually finding solutions.  I don't blame them.

The sketch below shows all 10 challenges in the series, as they draw hypertext transclusions from each other.  In addition to the exchanges among puzzles and their solutions, the series invokes some 77 links to Chapters in the Sky, Descriptive Glossary of Aviation Terms, 29 entries in Wikipedia, and dozens of other websites.

        1. The Clock Won't Wait
        2. Here Comes the Sun
        3. Landfall Navigating
        4. Live Reckoning
        5. Point of No Return 
        6. Simplexity Aloft
        7. Gathering Range
        8. Shoot the Moon
        9. Wages of Flight
      10. Which way, Amelia?
 
 

Suggestion: Amelia Earhart's last flight offers an opportunity to review and to apply the most powerful instrument for dealing with uncertainty: Discovering Assumptions.

Butler, Susan, East to the Dawn: The Life of Amelia Earhart, 1997 Da Capo Press. ISBN: 978-0-306-81837-0

Earhart, Amelia, Last Flight, 1937, Harcourt Brace and Company, Inc. ISBN: 0-609-80032-9

Gillespie, Ric. Finding Amelia: The True Story of the Earhart Disappearance. Annapolis, MD: Naval Institute Press, 2006. ISBN 1-59114-319-5

Klass, Joe and Joseph Gervais, Amelia Earhart Lives, 1970, iUniversity.com, Inc. ISBN 0-595-09038-9

Long, Elgen M. and Marie K. Amelia Earhart: The Mystery Solved. New York: Simon & Schuster, 1999. ISBN 0-684-86005-8.

Pellegreno, Ann Holtgren, World Flight: The Earhart Trail, 1971, Iowa State University Press, ISBN 0-8138-1760-9

Rafford, Paul, Jr. Amelia Earhart's Radio,  2009, The Paragon Agency, Orange, CA 2009, available in e-book form at www.Special Books.com, ISBN: 1–891030-35-3, ISBN: 978-1-891030-35-2

Reineck, Rollin C., Amelia Earhart Survived, 2003,  The Paragon Agency, Orange, CA, www.Special Books.com, ISBN: 1-891030-24-8, ISBN: 978-1-892030-24-6

Strippel, Dick, Amelia Earhart: The Myth and the Realities, 1972, Exposition Press, Inc., ISBN 0-682-47447-9

Westfall, Douglas, The Hunt for Amelia Earhart, 2007, The Paragon Agency, Orange, CA, available in e-book form at www.Special Books.com, ISBN: 1-891030-24-8, ISBN: 978-1-892030-24-6