Applying magnetic variation is trivial and pilots and navigators do it all the time.
If everything is trivial, why even create a flight plan? I suggest that it was not trivial and the fact they did not make it to Howland as proof.
As I said, applying variation is trivial, and every student pilot masters this requirement prior to their first cross-country flight, usually within 20 hours of their first flying lesson, during which time the student has also spent a little bit of his time learning to fly the airplane too.
Because he was hired as a navigator. This does not give him liberty to create a flight plan as he saw fit on a whim. If this were the case, I am sure that this would have been communicated in one form or another. I see no evidence that this was the case. The fact that they made it back to the flight line at 7:19 GMT contradicts this theory. If you took a match to the flight plan, there was no reason to head back to the flight line. If FN was so expert as to trash the flight plan, and head to Nauru, the heading from 5:19 GMT to 7:19 GMT makes no sense at all.
Oh yes it does, that is what a navigator is hired to do, that is why he gets paid the big bucks. It is his responsibility to decide how to navigate the aircraft from point a to point b, he is the only one with the knowledge in the plane who can do that.
There is an old joke. A new navigator is assigned to a B-24, flying bombing missions over the western Pacific during WWII, taking off from Moritai island and bombing Borneo. The pilot had a reputation of being a "hard ass." He yelled for the new navigator to come up to the cockpit. The pilot then pulled his .45 out of his shoulder holster, slapped it down on top of the instrument panel and yelled at the navigator, "I'll shoot any damned navigator that gets us lost!"
The navigator thought for a moment and then followed suit. He pulled
his .45 out, slapped it down on top of the instrument panel and said to the captain, "if we get lost,
I'll know it before you do!"
When you cut right to the chase, out over the ocean on the way to Howland, Earhart had been reduced to the status of a helmsman who had to steer the headings given to her on a note by Noonan. Earhart had no way herself to determine what way she should point the nose of the plane in order to ever see land again. She had no way to know what island the heading given to her by Noonan was taking them. On her prior ocean crossing flights, solo across the Atlantic and solo from Hawaii to California, she was dead reckoning and aiming for continents that she could not miss. The only issue on those flights was reliability of the engines and having sufficient fuel to reach the continent ahead of her. It did not matter if she wandered off course far to the right or left, as long as the engine kept making noise for a long enough period of time, she was guaranteed of reaching dry land.
And you still keep referring to "
the flight plan." As I have said before, we do not have their "flight plan" we only have a preliminary planning document prepared months before by a different person for an entirely different flight in the opposite direction with very different navigational considerations. Whatever flight plan Earhart and Noonan came up with incorporated a detour around the predicted storms based on current information that they had that was not available when Williams drew his strip chart many months before. Earhart and Noonan also had new information about the lights on Nauru that Williams did not have. If Williams did know about the Nauru lights he might have drawn his strip chart to go over Nauru, or maybe not, since it was a much easier route going towards Lae than going towards Howland. Noonan would have been remiss as a navigator if he didn't take these factors into account in making the actual flight plan for the actual flight from Lae to Howland. By the way, do you have any proof that they even took Williams' strip chart with them? (the document that you like to refer to as "the flight plan.") This actual strip chart is now in the Purdue collection so we know that chart did
not go on the flight. Was a copy of it made to carry with them? do you have any proof? Actually there is evidence that they did
not take a copy of this strip chart with them. This is not the only strip chart that Williams prepared, he made one for each leg of the route around the world. The entire set of strip charts is at Purdue so we know that none of the originals went with them. We only know of one copy of his strip charts that actually went on the flight, the one for the leg from California to Hawaii because Purdue has this copy with its hand written notations. Purdue doesn't have any other such strip charts for any of the other legs. Earhart sent back her charts when they had completed each leg and they are all at Purdue, an example of which is the Natal to Dakar chart that I have on my website. If they had also been carrying Williams' handywork with them then these strip charts would also have been sent back along with the other charts and we would find this second copy, most likely bearing some notations similar to the one for the Hawaiian flight, at Purdue and they are not there. So it looks like they left Mr. Williams behind when they started around the world eastbound.
In fact, for the Lae to Howland leg it is quite likely that they had "abandoned" Williams' "flight plan" even before they left the States. Noonan looked at the Williams' plan and said "no way, it is an entirely different navigational situation going to Howland than going the other way, towards Lae, which is basically aiming for a continent. I will work out a proper plan for this much more difficult route taking advantage of everything I can find along the route based on my experience of flying over the Pacific, experience that your Mr. Williams lacks." He may have planned to overfly Nauru even before leaving the States and certainly prior to departing Lae. Is there any evidence of this, you ask. Yep, the telegram from Nauru. Do you think the Nauruians just woke up one morning and said to themselves "gee, let's send an unsolicited message concerning the lights here on this island to Lae." Or is it more likely that it was sent in response to a telegram from Earhart asking for that information since she and Noonan had already been planning to fly over Nauru? Which is the more likely explanation of the Nauru telegram?
You also apparently missed this in my prior post which responds to your last question:
"Although the 0718 Z position is on the direct line from Lae to Howland it is also on the line from the 0519 Z position over Choiseul to Nauru."
When I lived in Chicago, I used to fly down to the Caribbean every winter to charter a sailboat. We would take off from Midway airport around midnight, overhead Chattanooga, land for fuel at Atlanta about dawn, overhead Jacksonville and then fly down the beach all the way to Ft. Liquordale. There we would rent a life raft, top off the tanks, fly east over Bimini before turning southeast and then landing on Grand Turk where we RONed, drank some pina coladas, and listened to some reggae. Next day we took off early, landed in the British Virgin Islands at the Beef Island airport and picked up the boat at noon. That was my standard flight plan. I haven't flown it in 30 years but I still remember that it was 1019 nautical miles from Midway to Ft. Lauderdale. But, even though that was my standard flight plan, there were many times when I didn't follow it. It was common to run into weather over Chattanooga where you run into the mountains, mountains make weather, so I would change my plan and head for Birmingham for fuel then this route took me down the center of Florida instead along the beach. Plans are made to be changed based on new information.
Noonan and Earhart did exactly what any flight crew would do, make new plans that incorporated new information. Airplanes do not run on rails nor are they constrained by lines painted on pavement, they can go anywhere they please on a whim, making changes in their route "on the fly."
If you can't get your head around flying examples then here is an example for our ground bound frends. Say you are planning a trip from Chicago to LA on United Airlines and when in LA you also plan to rent a car and drive out to Palm Springs. You ask a friend of yours, who is familiar with LA, his recommended driving route from LA to Palm Springs and he draws a line on a road map down "The 10" (Interstate 10) which goes to Palm Springs. But something comes up and you have to postpone your trip for several months, then when you are checking airlines you find that there is an inexpensive direct flight from Chicago to Palm Springs and you go that way. While in Palm Springs you still want to visit LA so you rent a car and plan to drive into LA and you still have your friend's road map with you. But, you see on TV that there is construction work on the westbound side of the "The 10" so you look at the road map, and then decide to take "The 60" instead of "The 10" since that road also goes into LA. You are not bound by the line drawn by your fiend on the road map that prevents you from considering new information and choosing a better route
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