Not that the last minutes or hours of NR16020 and her crew haven't been thoroughly examined as they are the subject of at least one major and rational theory of the 'end game': a landing on the reef at Niku.
Because the failure of radio DF at the end of the flight seems to figure so prominently in what happened, consdier an extract from Noonan's own comments about DF reliance and reliability in trans-oceanic flight of the 1930's from Gary LaPook's website
"Freddienoonan" - see pdf file there entitled "Noonan's 1936 newspaper article" and subheading "Radio Element" therein for some interesting historic background.
Also see
"Fred Noonan's Pan Am Memo" in which he gives a detailed accounting of the application of radio for direction finding means. See especially his closing paragraph which sums nicely his view of the radio at the time (1935). Of note, while radio was an important development with much promise, it clearly had limitations. What FN does provide in sum, however, is that the radio D.F. methodology was quite valuable at 'the end of the line': final homing once a destination had been roughly achieved.
- I suggest that this memo provides insight into FN's expectations of how radio would be applied on the Earhart world flight, especially in locating Howland island at the 'end of the line'.It is apparent that the success of D.F. as a tool in the manner FN spoke of would depend on several factors:
- Appropriate equipment (and frequencies)
- Capable operator(s)
- A reliable signal
NR16020 suffered in all of these regards. FN was then seemingly called upon to apply all of his many skills to find an alternate solution that NR16020 might finally emerge at Howland island. Among these seem to have been some combination of celestial navigation, an application of dead-reckoning and dependence on reasonable spatial awareness of his environment - the open Pacific and her scattered islands in various directions from where he thought he was located.
From these tools and this picture in FN's mind as derived from charts and experience would be the hope that NR16020 could still find Howland, or failing that, some other landfall (no doubt FN was keenly aware that he was riding in a landplane over an expanse of water...).
Herein also lies much of pro and con - from what the logical approach would be, to what FN would have been capable of and what his background suggests he might have done.
If the celestial skills of FN are to be believed, then FN had at his disposal a means of deriving a reasonable placement somewhere in the Pacific. No question there would have been limits, but to be able to determine something productive seems likely.
That said, back to radio D.F and FN's own thoughts about that resource - obviously celstial nav did have an annoying set of limitations which made the prospect of final homing to a fine point by D.F. signal highly desirable.
So NR16020 was in a 'fix' - without a 'nav fix'. What FN would do AE would surely follow, as would NR16020.
---
I am aware of critical review of the "LOP". In particular, Gary LaPook counts the "sunrise LOP" as "myth" in his article
"The myth of the "sunrise" LOP" on his site. I find his article thoughtful.
I don't agree that the idea can be dismissed as myth - FN had too many tools and too much experience to have not been able to have used some form of this aspect of celestial navigation quite effecively. Somehow a
"line 157 337" was eventually derived. It would be very odd for that line to just happen to be perpendicular to the sunrise azumith of 67 degrees that day.
Timing of the shot seems to be a major point of argument for Gary. Exactly
when the base siting was taken seems to matter almost not at all as I've labored through this discussion.
What matters most is that some form of this navigation exercise resulted in the placement of a line on the globe according to what we can understand from AE's last transmissions to Itasca that morning.
FN had an accurate
time-of-day at-hand, so far as we can tell - Chater recounts the time-synch effort prior to departure from Lae in good detail. FN was not careless, except in his trust of AE for management of radio duties and coordination. He ensured that his tools were sharpened and available.
I encourage those who have not done so to read these articles for themselves, and other information on TIGHAR, at Gary's site, and others for themselves.