My friend who has his own boat and runs charters up and down the Atlantic coast says that the "line" AE gave was a huge clue out there in the vast, empty Pacific but useless over land or areas containing many islands. He said that his first instinct would have been to ask for charts of the area around Howland and to lay that line on the chart and move it around to see what it intersected (given the plane's range and speed) since there's so few islands there. But he said that assumed a lot of hindsight that she had landed rather than ditched. Agreed.

No hindsight. The Navy reached that conclusion at the time.  They only changed their mind when no aircraft was seen at Gardner.

Does anyone believe Earhart would have returned to Lae if someone had radioed her that her antenna came off on takeoff? Seems many showed indifference toward her.

A. No one seems to have noticed the wire laying out on the runway until much later.
B. With the antenna gone, how could they tell her anyway? 

Thirst, drinking contaminated water, and within a week I think they died.

The archaeological evidence suggests she had a system for collecting and boiling rain water.  The remains of fish, birds and turtle suggest she survived for a matter of weeks, maybe months.  She seems to have caught and eaten one adult and at least one baby sea turtle. Sea turtles are impossible to catch unless they are onshore.  They only come on shore to lay their eggs.  At Niku, turtles breed in July and lay their eggs in September.  Earhart may have survived at least until the eggs hatched in October.

As for the fragment broadcast and my comment about them saying they were north of Howland, that was not in Betty's notes but came from your presentation about other post-loss signals.

I think you must have misunderstood something I said.

If it was a true broadcast, then FN committed a whopping navigational error leading AE and he to believe they were north of Howland. Misidentifying one of the Gilberts from the air in cloudy conditions and altering course to the South might have set them up for this disaster and explain why AE flew south on that line (mostly) sighting Gardner some 380 miles away and south of Howland still believing they were north of Howland.

They were over the Gilberts in the middle of the night with an overcast blocking any moonlight.  The islands had no electricity.  They were essentially invisible. There is no evidence Noonan made a navigational error.  The error was Earhart's in not understanding how to use her radio direction finder.

Posts referencing the Glenn Miller Project need to go in the Glenn Miller Research section of the Forum.

Ric, are you planning on mounting a find and recover effort for Mr. Fisher's (Glenn Miller's) mystery plane in the English Channel at the old-fashioned coordinates he gave? Any Robert Ballard/Nat'l Geog. interest in this especially now with the parachute cords mystery cleared up? I wonder if any other fisherman has "netted" on this object in more recent times? Is this documented anywhere? Would local scuttlebutt from more recent times and fishermen be useful? If the plane is covered in discarded "ghost" nets (like the Andrea Doria), the dangers faced by submersibles/divers in searching and recovery will be extreme but might help pinpoint the site. Wrecks of all sorts must be legion in the Channel.  Even with an approximate location, it's still daunting.

Ah, Ric! I was confused by your use of 10.5 hours in your original response & thought Itasca was part of the 10.5 hr deal for Baker & Howland Island posts. From the log of the Itasca, they were using "+11.5". So, that's cleared up. Okay, Betty didn't hear this on July 2. Itasca further heard nothing intelligible after 20:45 GCT on July 2 (16:45 EDT at Betty's home). I don't know if Betty tried to listen in on subsequent days but there's no "notes" and perhaps the plane did disappear shortly after this transmission but atmospherics may no longer have been favorable for reception on Betty's radio. I'm assuming that Earhart & Noonan sat in the plane with the microphone keyed while conversing in order for Betty to hear most of the anecdotal stuff being said? "Get the suitcase in the closet...." must be a last farewell and sort of giving up hope of being heard and found. We might assume that waves/tide broadsided the Electra and snapped off the landing wheel thereby, thereafter, rendering useless any engine use and radio use (after the battery died). My friend who has his own boat and runs charters up and down the Atlantic coast says that the "line" AE gave was a huge clue out there in the vast, empty Pacific but useless over land or areas containing many islands. He said that his first instinct would have been to ask for charts of the area around Howland and to lay that line on the chart and move it around to see what it intersected (given the plane's range and speed) since there's so few islands there. But he said that assumed a lot of hindsight that she had landed rather than ditched. Agreed. Such a shame that the spotty radio waves and those presumed voices of AE & FN never were heard to clearly say they had landed on an atoll and near an old shipwreck. Chance did not favor those two. Does anyone believe Earhart would have returned to Lae if someone had radioed her that her antenna came off on takeoff? Seems many showed indifference toward her. As for how long they lasted, Bevington's chronology and how he walked the island without carrying water speaks volumes, drinking four pints upon his return from "exploring." Thirst, drinking contaminated water, and within a week I think they died. Imagine if Bevington had stumbled upon the skeletal/human remains! The hunt continues!  As for the fragment broadcast and my comment about them saying they were north of Howland, that was not in Betty's notes but came from your presentation about other post-loss signals. If it was a true broadcast, then FN committed a whopping navigational error leading AE and he to believe they were north of Howland. Misidentifying one of the Gilberts from the air in cloudy conditions and altering course to the South might have set them up for this disaster and explain why AE flew south on that line (mostly) sighting Gardner some 380 miles away and south of Howland still believing they were north of Howland. So many errors in judgment. I hope TIGHAR helps to write a correct and fitting epitaph to the mystery.   

The eBay folio is definitely a later model, as it has a phone number with an area code written inside. That dates it to 1947 or later. I also think her document folio was larger than the eBay example, which I posted just to illustrate that Talons were used on that sort of bag in that era. It wasn’t a typical chart bag as carried by airline pilots, but maybe held the charts she needed for any particular leg. . 

Larger luggage such as a suitcase or a B4 bag would require a larger zipper and slide. The artifact was likely from a trouser, flight suit, or small bag.

As a fan of leather flight jackets, I know Talon has been the gold standard for zippers from the 1930's all the way to today.

My leather flying jacket is a reproduction A-1 (1927), the first design produced for the Army Air Corps. No zipper.  Buttons.

The zipper on the Ebay folio does look similar to ours.  It has the "auto-lock" feature on the pull.  Ours is a size "06" (too small for a jacket or even a fly).  There's no way to scale the photo on Ebay so it's hard to know if it's the same size as ours.  There's also no way to know whether Amelia's briefcase had a Talon zipper.
I can see her bringing her briefcase full of important papers ashore if she was about to lose the airplane. Would she still have it weeks, or months, later?
Maybe.

The 'Rivet pattern' appear raised, almost like a sea cucumber IMVO

I know the OP is long gone, and there is some history, but this thing sure looks like one of those old-timey safety razors. Fred certainly would have had one, as would many of the crew of the Norwich City.

Most likely 2 sea cucumbers about to make a 3rd.

Betty did not make a notation of what day she heard Amelia, but there is one clue in her transcript that suggests the date was Monday, July 5.
One of the first entries in Betty's notebook is "here put your ear to it" allegedly spoken by Amelia.  She can only be speaking to Fred.  Put your ear to what? Why? There must be something she wants Fred to put his ear to so that he can hear something.  There must be a purpose to that request.
The only thing I can think of that he could put his ear to are the radio earphones and there must be something she wants him to hear that will serve a purpose.  We know from the context of the transcripts that Fred is upset, almost panicky.  Amelia has been calling for help.  Any kind of response to her calls would be greatly reassuring. So, the question is, was there any day when someone was transmitting to Earhart shortly after 4:30pm St. Petersburg time (20:30 GMT/ 09:00 ITASCA time)?
According to the Itasca Radio Log,
•  As has been shown, Friday, July 2, is not a possibility.
•  On Saturday, July 3, nobody tried to call Earhart during the time period in question.
•  On Sunday, July 4, Chief Radioman Bellarts heard "not one signal" on 3105 at 09:00 but called Earhart in voice at 09:30. No response.
•  On Monday, July 5, at 09:57 Chief Radioman Bellarts "hearing signal on 3105 / little low in frequency".  At 10:00 and again five minutes later, Bellarts "called Earhart // 3105 key" (in other words, in Morse code).  Earhart would not be able to understand the message but a response on her frequency would be an indication that her calls were being heard by someone.
•  On Tuesday, July 6 through Friday, July 9, nobody tried to call Earhart during the time period in question.

So there were two days, Sunday the 4th and Monday the 5th, when Earhart could have heard something on her frequency (3105) during the time Betty heard her say "here put your ear to it."  According to Betty, her father came home from work during the time she was hearing Amelia and her recollection was that her father did not work on Sundays, so Monday, July 5th is the date that best fits.

Additionally, since radio operators recorded "we are on the line..." and we are 'running' on the line..." I ask or raise the possibility that Itasca didn't hear everything that Amelia Earhart said on the radio.

That is entirely possible.

I'm referring to "We are on the line...." and wonder if it was actually made in-flight? (as in, "we are somewhere on the line"?) For AE, so hopelessly lost and not knowing where they were or the name of the island, was "...on the line..." a futile attempt to convey where they had landed?

If the message had ended with "We are on the line 157 337" you could make that argument, but she went on to say "running on line north and south."  That's a present-tense statement of an action she is engaged in at the time of the transmission.  She can't be running on the line if she has landed.

My math says that 08:55 Itasca time + 10:30 = 19.25 GMT.

Perhaps you could cite your source for Itasca using + 10:30.  My source for Itasca using +11:30 is page 5 of Commander Thompson's official report Radio Transcripts Earhart Flight

When one uses the wrong math, Ric, the conclusions reached are equally erroneous.

I agree.