Post-loss Radio Messages--Overview

World press reported many post loss radio signals like that heard by Nauru Radio published in the 5 July 1937 Canberra Times. (Courtesy: Australian Newspapers Beta Service)

• Post-loss Radio Messages--1937 Timeline

A complete exposition and analysis of all reported radio contacts with the lost aircraft is to be found in Finding Amelia, by Ric Gillespie; the book contains a wealth of primary sources in a research library on a companion DVD.

• Betty’s Notebook. Notes taken by a teen-age girl in July of 1937 while listening to a short-wave radio.
• Dorothea Garsia Diary, Nauru, 1934-1938.
• The Pan American Airways Memos describe the efforts Pan Am made to take bearings on signals apparently coming from the downed aircraft.
  • Wake Island.
  • Midway.
  • Summary by G.W. Angus.
  • K.C. Ambler's report.

Technical considerations

Bearings taken after July 2 suggest that a transmitter was operating in the Phoenix Islands.

• Harmony and Power: Could Betty Have Heard Earhart on a Harmonic?
• Radio Direction Finder Analysis.
• The Radio Riddle.
• Post-Loss Signal Statistics with Tide Information.
• Post Loss Radio Signals (October 2000).
• WE-13C Transmitter Harmonic Power Output.

Battery Life

"Both batteries were rated at 85 ampere-hours. If both were at full charge on arrival at Niku -- a reasonable assumption -- there would have been enough charge for about 90 minutes of transmission time. The total transmission time required for all of the credible post-loss signals is 451 minutes."

Names in the news

281 North

"Cosmic Significance," TIGHAR Tracks, Vol. 9 #3, 15 September 1993, p. 7.

Late on the night of July 4, 1937 – two and a half days after Amelia Earhart and Fred Noonan disappeared – three operators at U.S. Navy Radio Station Wailupe, Hawaii heard the following message fragments:

TWO EIGHT ONE NORTH HOWLAND CALL KHAQQ BEYOND NORTH DON'T HOLD WITH US MUCH LONGER ABOVE WATER SHUT OFF

KHAQQ was Earhart’s radio call sign and the signals were received on Earhart’s nightime frequency of 3105 KCs. The message was sent in “extremely poor” Morse code and only partial phrases could be understood.

This message was taken very seriously at the time and every available vessel – the USCG Itasca, the USS Swan, and a British freighter, the S.S. Moorsby – was diverted to search the ocean 281 miles north of Howland Island. They got there the next evening but found nothing. Reinforcing their frustration was a message from Lockheed officials stating that the location of the Electra’s radio gear would make it impossible for the airplane to transmit if it was floating.

Los Angeles hoaxers

• Walter McMenamy and Karl Pierson

"Two ham operators in Los Angeles - Walter McMenamy and Karl Pierson - were responsible for a great many of the first reports of post-loss signals but the pattern of what they said they heard is completely at odds with what was being heard in the search area and all the information they claimed to have gotten from Earhart could have been had by simply monitoring Coast Guard radio traffic. McMenamy and Pierson were almost certainly perpetrating a hoax - perhaps with the best of intentions (i.e. to encourage a large Navy search) or perhaps just to puff their own reputations as hot-shot radio experts, or some of both - who knows? The point is that the patterns of what they reported hearing - the times, the frequencies, the content - sticks out like a sore thumb when viewed in the context of the other reports."

• Howard Coons
• Ernest Henderson
• W. E. Tippin

Related material

• Finding Amelia--a book by Ric Gillespie based on an analysis of all available post-loss radio messages.