TIGHAR
Amelia Earhart Search Forum => Celestial choir => Topic started by: Gary LaPook on February 20, 2012, 04:26:55 AM
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Some have claimed that the Williams' strip chart and list of courses for the Howland to Lae flight as the flight plan that Noonan and Earhart used for that flight but that is very unlikely. First, keep in mind that there is no proof that Noonan used Williams' plans and, since Noonan was a more experienced flight navigator than Williams, Noonan most likely did his own computations, not trusting the work of others. I know I would have if I were in Noonan's position, I have always done my own computations in the past, I don't rely on anybody else for this type of work.
But, in fact, there is strong evidence that Noonan did not use Williams' flight plans. All you have to do is compare Williams' strip chart for the Atlantic crossing from Natal to Dakar with Noonan's chart for the crossing and the differences jump out at you. I have attached both of these charts. Williams' strip chart for this route is just like the one for the Lae to Howland leg, with a line plotted connecting calculated points along the great circle, also spaced every 2° 30' of longitude, just like on the Howland to Lae strip chart. He calculated the distances in statute miles between these points, consisting of seven legs and each of these legs is a different length. He also marked the expected flying time for each of these legs and these times are all different since the legs were all of different lengths. He calculated the true great circle course from Dakar to Natal at various points along the great circle starting at 221.6° near Africa, 220° in the middle of the Atlantic and 220.4° near Brazil. Because the variation also changed along the line, the magnetic course is listed by Williams as 240° all the way and 060° for the eastbound direction.
Now look at Noonan's chart. He did not plot any great circle points, he just drew in a straight line, which is the rhumb line, from Natal to Dakar. He did this simply by using a straight edge laid on the chart from Natal to Dakar. How do we know he did it this way? Look at the bottom of the chart and you will see that the course line and the other line, ten degrees to the left of the course line, extend past the neat line (that is the line making the border of a chart) and converge on the position of Natal. Since Natal is not on this chart, Noonan used the standard method used by navigators for this situation, you simply attach an extension piece of paper to the chart on which you plot the departure and then lay your straight edge from that point to the destination. Ask any of your pilot friends how they plot a course on their Sectional Charts and they will tell you that this is the standard method that they use when both the destination and the departure are not on the same side of the chart.
Noonan then marked the magnetic course as 061° for the first part of the route and 060° for the end near Africa, not the constant 060° that Williams used for the whole route.
Noonan then marked check points spaced evenly at 150 SM intervals representing one hour of flying time for each leg at the planned speed of 150 mph.
We can also see that Noonan actually used nautical miles for his navigation. Next to the left most line, ten degrees to the left of the course line, just at the bottom of the chart, we find Noonan's notation "410" which is the distance in nautical miles from Natal to that point crossing the equator at the bottom of the chart. Follow further up that line and you will also find Noonan's notation of "1017 mi from Natal" and those are also nautical miles.
So, it is very clear that Noonan had a very different method of planning his routes than Williams did so it is most unlikely that he used Williams' chart for the last leg but it is highly likely that he used used own, his preferred methods when planning the Lae to Howland leg. Unless someone can come up with evidence showing that Noonan used Williams planning documents we can conclude that he did not but that he did his own planning and plotting using his methods that he showed us on the Natal to Dakar chart.
I would bet money that Noonan chuckled, as did I, at all the unnecessary work that Williams did, planning all those unnecessary great circle points and courses, when Noonan knew, based on his superior flight navigation experience, that a simple rhumb line was the better way to go.
gl
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I believe you are attempting to prove a negative. Lack of evidence is not evidence to the contrary. Can you produce any evidence that he did not in fact just follow the previous plan?
I can think of a good analogy. I write software for a living. Through the decades, I cannot tell you how many times I have encountered absolute rubbish code that should have been immediately thrown away. Some of these systems are safety critical and often very dangerous. Logic should dictate that these pieces once identified should be immediately re-written. Then there is reality.
Then comes the real issues of the work place. First, there are the issues of money. Companies rarely want to spend a dollar to re-work something that they have already paid for. There are always budget issues and timing issues that prevent code from being re-worked. Often out of laziness and unwillingness to spend more money the problems are forgotten and neglected.
Add in lazy people who do not really care what they are doing as long as they are making a paycheck and you have a completely reasonable explanation why very little software is ever re-worked. Unless customers are calling and complaining or someone dies, you never would know it. The garbage code continues to run, sometimes for decades.
While obviously FN had lots of spare time, it is quite possible that he was lazy about this return flight and might have forgotten or lost his reference material along the way. I thought I read something about FN losing an Almanac but I cannot recall where that was. Something about it being lost out of a window. Maybe that is just a story, who knows.
Is laziness, perhaps a drinking issue, and perhaps lost reference material enough to speculate that he used the Williams chart? I think that is plausible.
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I believe you are attempting to prove a negative. Lack of evidence is not evidence to the contrary. Can you produce any evidence that he did not in fact just follow the previous plan?
I just did. Is laziness, perhaps a drinking issue, and perhaps lost reference material enough to speculate that he used the Williams chart? I think that is plausible.
You can speculate all you want but I just provided proof that Noonan did not use Williams' chart on a prior leg so now it is your turn to provide a chart showing that Noonan did use Williams' chart on a different leg or else all you have is your speculation. In addition I posted long ago about Noonan's navigation on the Oakland to Hawaii flight and that navigation also did not look anything like a Williams flight chart. On both the Hawaii and Dakar flight the plane was more than 100 NM off the course line at various points, he did not slavishly attempt to stay on the course line.
gl
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Well, he must have created his own where they were not already provided to him correct?
You cannot prove that he did not use Williams flight plan for the reverse flight and you currently believe that the Williams chart is correct on the return flight so why would FN not believe so as well?
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Well, he must have created his own where they were not already provided to him correct?
You cannot prove that he did not use Williams flight plan for the reverse flight and you currently believe that the Williams chart is correct on the return flight so why would FN not believe so as well?
Williams drafted the Natal to Dakar strip chart so that was available to Noonan but, as we can see, Noonan chose not to use it. Why would Noonan choose not to use the Williams' charts, that's easy to answer, because it was Noonan's life that was on the line, he was in the airplane and if they got lost then he died, not Williams. Experienced navigators trust their own work above the work done by anybody else.
gl
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HUM---Noonan "chuckled" over William's charts? In light of the events that happened, maybe he should have thought about it instead of chuckling. Williams probably isnt chuckleing though. He probably laid out the route charts to the best of his ability, AND to the success of the flight. I would guess that after hearing that the flight didnt make it to Howland, he may have felt some responsibility, until realizing that Noonan did his own route.
It doensnt matter who you are, what you do, how many degrees you have-------there is someone out there that is better, more experienced in a specific job than you are. Everyone should learn from that.
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And the point of this particular nit is? Other than obfuscation, I'm not seeing one.
But maybe that's just me.
LTM,
Monty Fowler, TIGHAR No. 2189 CER
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"Why would Noonan choose not to use the Williams' charts, that's easy to answer, because it was Noonan's life that was on the line, he was in the airplane and if they got lost then he died, not Williams."
That was the point I was making, Monty. It doesnt matter if Noonan used William's charts or not
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Tom
"It doensnt matter who you are, what you do, how many degrees you have-------there is someone out there that is better, more experienced in a specific job than you are. Everyone should learn from that."
An interesting generalization. I remember a man named Albert Einstein, who developed the Special Theory of Relativity, the General Theory of Relativity, The Photoelectric Effect Theory, etc.
Who exceeded his accomplishments in these areas?
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Throw the Williams chart out of the window - no impact that I can see with Mr. Noonan in the back. The chart is informative and interesting - and provides a reasonable example of how we might expect the flight to progress. But it's also clear that we'd expect FN to use whatever methodology he was most confident in. I think we'd rationally expect that he would have altered his plan as he deemed necessary along the way.
LTM -
It looks like we finally agree on something. That is the point I have been trying to make for awhile Jeff, because so many have hung on every nuance of Williams' plan, as though it were gospel, in doing their own analyses of the flight path of the Howland flight and this reliance is misplaced.
gl
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So you agree Gary that FN would have adapted his plan along the way as he deemed necessary. So faced with the fact AE and FN did not find Howland, is it safe to say a rationale, experienced, trans Pacific qualified, ADAPTABLE navigator might say to AE " Let's just search locally until we find Howland. Yes, I know there are other islands we have the fuel to reach Amelia, they are printed on my chart, and I know how to navigate to them, but let's just search around here until we run out of gas and crash. I know we dumped all our survival gear Amelia but lets just do the search thing."
Wouldn't a better plan be to work the fuel consumption and alternate plan backwards? Pick the Phoenix Island group and calculate flying time there. Figure out what spare flying time they had remaing to play with and use that time to search? Times up and they head south. But they get there sooner because they were further south of Howland than originally planned so now they land on Gardner with spare fuel to make radio calls with. Pure speculation on my part, but an ADAPTABLE navigator like FN, as we all agree he is, might just be that adaptable.
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If the two approaches are so close, why belittle the application of Williams' chart as a reasonable basis for the 'plan'? ;)
I checked his math and he was amazingly accurate and he had to do the work using trig tables and logarithms and I used my calculator so my hat's off to his computational ability. But if I asked you to open a can of soup and instead of using the can opener on my counter you went to Home Depot and came back with a chainsaw, then I would belittle you too. Either method will open a can.
gl
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LOL!! A breathe of fresh air Jeff!! I got this great mental image of Gary in a splattered kitchen with chain saw in one hand and can opener in the other.
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Jeff, I think you and I will be lucky if Gary even talks to us at the symposium. I'm guessing an invite to dinner is just not in the works.
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Plus, although I agree that FN was likely more reliant on taking shots along the way to nudge the course as needed, the fact is a simple rhumb approach DOES have some built-in error that MUST be accounted for along the way. Williams' is the only approach that gives a truly accurate theoretical steer, segment by segment - now which is truly the best DR policy here? I'd go with Williams in that strict sense; I merely agree that FN seemed to have a practical approach that probably worked well - apparently until this last flight.
I don't know where you ever got the idea that a great circle is any more accurate than a rhumb line, they are both equally accurate, either one will get you to exactly the same point. If Earhart could fly a perfect course, no wind no compass errors, etc. and if she had just kept the plane on a heading of 078.1° for 2556 SM then she would have hit Howland the same as if perfectly flying Williams' rhumb line segments that approximate the great circle.
There are times when computing and flying a great circle is worth the additional effort, not because is is more accurate but because the length of the great circle is shorter than the rhumb line. Try this on Google Earth. As a starting point use 43° 00.0' North, 88° 00.0' West. For the end point use 43° 00.0' North, 85° 00.0' East and have Google Earth calculate the distance in nautical miles. You will notice that the initial course takes you almost straight north and the final course is almost straight south. I picked those two spots because it is easy to calculate the rhumb line between them. Since they are both at the same latitude, the true course is straight east, 90.00000000000000°. To compute the rhumb line distance figure the difference in longitude, 88 + 85 = 173 degrees. At the equator each degree of longitude is 60 nautical miles so the space between these two longitudes, at the equator, is 173 x 60 = 10,380 NM. At the latitude of 43° the length of a degree of longitude is equal to the cosine of the latitude times the 60 NM distance at the equator. So to find the distance between our two points we just multiply the 10,380 NM times the cosine of 43°, which is 0.731353, so the distance on the rhumb line between these two points is 7,591.45 NM. Compare that to the Google Earth result for the great circle course that passes near the north pole.
If you don't want to use Google Earth, you can use the standard formula for computing the length of the great circle:
GC dist. (in NM) = 60 x arc cos[ sin lat (start) x sin lat (end) + cos lat(start) x cos lat(end) x cos difference in longitude(between start and end)].
gl
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Harry---you got me on that one---but I think we can agree that Albert was a one of a kind.
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And it happens that while we could 'chuckle' at the Lae-Howland segment, that part just HAPPENS to lie close to the equator - the whole world route DID NOT; and the Lae-Howland segment was JUST THAT - A SEGMENT. Why would he do any less than his best at any part of the whole thing?
Yes the whole route did lie close enough to the equator that there was only a negligible advantage to using the great circle instead of the rhumb line. I have all of Williams' strip chart. The only ones he used the great circle for were for the long ocean crossings, Oakland to Honolulu; Honolulu to Howland; Howland to Lae; and Dakar to Natal. Using the great circle for Oakland to Honolulu instead of the rhumb line would have saved 9.6 SM and we know that Noonan didn't stay anywhere near the great circle on that flight. For the Honolulu to Howland leg, the great circle saved 0.4 SM; Howland to Lae, 0.1 SM; and Dakar to Natal, 0.1 SM. Total savings for flying all the way around the world is 10.2 SM out of a total of more than 25,000 SM. Looks to me like Williams was charging by the hour. :D
gl
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So ... does this mean that Gary is coming to DC in June to lay it all out? If so, first round is on me.
I'm serious, Mr. LaPook. Ask Ric. I put my money where my mouth is, when the occasion demands. How about you?
LTM, who had to work on this national holiday because the paper won't push itself,
Monty Fowler, TIGHAR No. 2189 CER
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Monty, Gary has been trying to say to us lately that he has already laid it all out in many posts since 2002 when he joined. He has told us, only in the last few days, that he believes in the crashed and sank theory. I don't know what he can lay out about that. I hope he is coming to the symposium just so I can meet him. While I tend to give him a hard time on some of his posts I have the utmost respect for him and would like to discuss his ideas over a libation. Or two....
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I don't know where you ever got the idea that a great circle is any more accurate than a rhumb line, they are both equally accurate,...
So, how can a rhumb line EVER be AS ACCURATE as a well laid out great circle, unless right along the equator? It can't - simply because a rhumb line really amounts to flying a curve (if above or below the equator) - therefore its a bit deceiving to the casual observer - and accuracy is in fact lost. Of course as we both know, for shorter distances over land where landmarks are much more prevalent, a rhumb line is a fine thing - there's little lost, and certainly no more lost than is easily made-up by the use of occasional landmarks.
I hate to be this blunt Jeff, but you are just plain wrong. We can argue about the facts of the Earhart case but you can't argue that two plus two does not equals four. Rhumb line navigation is the standard way that ships have always been navigated and to a much higher level of precision than aircraft. I posted an experiment you can do on Google Earth here (https://tighar.org/smf/index.php/topic,607.msg10543.html#msg10543), and the example I used had both points at the same latitude. The rhumb line course between those point is exactly 90.00000000000000000000000000°, straight east from Milwaukee to the end point in Asia and if you can fly a perfect heading of 90.00000000000000000000000000000° without any errors or cross wind then you will end up at the end point. The course is exact. And this goes for every other rhumb line too. Of course flying either the great circle or the rhumb line will have the same level of errors in attempting to stay on the chosen line.
What course line, great circle or rhumb line, appears as a straight line depends on the projection used to create your chart. On Mercator charts a rhumb line is straight and the great circle appears as a curved line. On a Gnomic chart it is just the opposite, the GC is straight and the RL is curved. You use Sectional Charts when you fly. Those charts are based on the Lambert Conformal Projection and on these charts a straight line APPROXIMATES a great circle. On this type of chart the meridians are not parallel but converge toward the pole. I am sure you were taught, when plotting a course on your sectional, that you should measure the true course with your plotter placed on the meridian line nearest the midpoint of your course line, not at the meridian near your starting point. You didn't know it, but you were actually measuring and then flying the rhumb line course, not the great circle. Take out a sectional and prove it to yourself. Lay out a long course line and then measure the direction at the central meridian as you normally do. Then go back to the meridian nearest the departure and lay off the course direction you just measured. This line will go south of the first, approximate GC, line. Then where that line hits the next meridian lay off the course line again in the direction you had measured and do this with subsequent meridians. You will end up drawing a curved course line between your departure and your destination that is south of the straight line. The easiest way to do this test is to pick two spots at the same whole degree of latitude. The course you measure will be 90 degrees and if you follow the procedure you will end up drawing in the parallel of latitude since that line crosses each meridian at 90 degrees but you don't have to draw it yourself since it is printed on the chart for you already. The parallel is the rhumb line between those two points. On a Lambert chart this curved line is a rhumb line and this is the line you will actually fly without a cross wind and without looking out the window, this is the way the autopilot will take the plane. And now that you are looking at this carefully, it should be obvious that you were measuring and flying a rhumb line and not a great circle. You can't measure a single course line in a single direction and be following a great circle as Williams' careful computations demonstrate. To actually measure a great circle on the Lambert chart would require you to measure a new course at all the meridians that your course line crossed and make up a table like Williams did of the changing courses necessary to define the great circle. So the proof that you can measure and fly a rhumb line as accurately as a great circle is that you have gotten to your destinations and you have been flying rhumb lines even though you didn't know it. You have been able to get to your destinations, haven't you? ;) Good, then I'll call you as my first witness.
If Earhart had been able to maintain a true course of 078.1° for 2556 SM then she would have hit Howland (within the approximate 4 SM accuracy available from a course expressed to one-tenth of a degree.)
I have attached several pages from the American Practical Navigator, U.S. Navy Hydrographic Office Publication Number 9, the standard reference book used by the Navy and all American surface navigators.
gl
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There are times when computing and flying a great circle is worth the additional effort, not because is is more accurate but because the length of the great circle is shorter than the rhumb line. Try this on Google Earth. As a starting point use 43° 00.0' North, 88° 00.0' West. For the end point use 43° 00.0' North, 85° 00.0' East and have Google Earth calculate the distance in nautical miles. You will notice that the initial course takes you almost straight north and the final course is almost straight south. I picked those two spots because it is easy to calculate the rhumb line between them. Since they are both at the same latitude, the true course is straight east, 90.00000000000000°. To compute the rhumb line distance figure the difference in longitude, 88 + 85 = 173 degrees. At the equator each degree of longitude is 60 nautical miles so the space between these two longitudes, at the equator, is 173 x 60 = 10,380 NM. At the latitude of 43° the length of a degree of longitude is equal to the cosine of the latitude times the 60 NM distance at the equator. So to find the distance between our two points we just multiply the 10,380 NM times the cosine of 43°, which is 0.731353, so the distance on the rhumb line between these two points is 7,591.45 NM. Compare that to the Google Earth result for the great circle course that passes near the north pole.
Here is the answer to my little experiment. The great circle course is only 5,644.18 NM long while the rhumb line between the two points is 7,591.45 so you would save almost 2,000 miles using the great circle. This is obviously an extreme case that I chose to illustrate this point. The initial great circle course leaving Milwauee is almost straight north, 005° T and the final course is almost straight south, 175° T. On the way the course changes through all the intermediate directions, 6 then 7 then 8.....then 90.....then 120....then, finally 175.
The rhumb line never changed, being 90.000000000000000000°.
gl
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An interesting example might be a proposed flight plan that FN would have created. I think that this would prove to be an interesting study.
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Not sure if I've seen this line quoted before. It's from Williams. Not saying its true or not, but rather interesting into the 'thinking' that was going on at the time.
The Miami News - Jul 3, 1937
The man who mappeed Amelia Earhart's globe-circling flight, Lieut. Commander Clarence S. Williams, expressed belief today she may have landed at Baker island, some 40 miles south of Howland island, the dot of land she missed.
"The eight degrees may be the secret of why the fliers did not strike Howland as scheduled. They may have allowed for the effect of a wind which may either have died down druing the night or may have been changed altogether by some gavrant storm area. If the fliers allowed for a drift of eight degrees, and if the wind died down - so that this correction was not needed at all - they might have gone as far as 180 miles to the south of Howland island."
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... by some gavrant storm area. ...
"gavrant" = "vagrant"?
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"gavrant" = "vagrant"?
I guess I'm not the best editor either....
"gavrant" = (sic) = ;)
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"gavrant" = (sic) = ;)
No blood, no foul.
I like words. I would have added "gavrant" to my collection if it had been real. It sounds as though it should mean something.
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Sure = go ahead and add it to your colleciton! ;D
gav·rant adjective \ˈgāv-rənt\
Definition of GAVRANT
a : Characteristic of, relating to, or having a tendency to make typograhical errors while posting in forums on the internet.
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Erik
Your sense of humour is awe inspiring.
It (gavrant) could also be made an adverb ny adding ly, i.e. gavrantly, the act of giving in the hashion of a rant, gave rantly LOL