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Author Topic: LaPook Hypothesis: Box Search around 157-337  (Read 125854 times)

Malcolm McKay

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #90 on: July 05, 2012, 10:15:30 PM »

Don't know if anyone else has noticed the contradictory evidence being put forward in separate threads. When you look at them together it doesn't add up.
The ability of Fred Noonan to navigate accurately, get fixes on the sun, the moon and so on yet, they couldn't see Howland.
The probability of them implementing a successful search pattern that would lead them to Howland yet, they couldn't see Howland.
The ability of the Lambrecht SAR team to see someone waving from a beach yet, the failure of AE and FN too see Howland and Itasca and the smoke and Howland Island, all of which are a tad bigger than someone waving from a beach but, they couldn't see Howland.
When you take all these bits of the jigsaw that have been analysed and shown as likely and, put them together, it doesn't make sense.

Well that pretty well sums up my thoughts on the matter - there is no holistic view unless you massage individual parts of the puzzle to fit the hypothesis which I suspect no one would disagree is not a safe means to construct a working hypothesis. It is the same with the artifacts none can be safely given Earhartian provenance yet individually one or some might be - and its the "mights" that drive the argument. I don't like "mights" I prefer "ares".  :)   
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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #91 on: July 05, 2012, 10:41:05 PM »

Gary,

Thanks for the point out to the background data.  ...  Your references are mostly post 1940 and much was learned during the war years as military aviation dramatically advanced the navigational knowledge.  I had seen a few of your references but not many but I had seen a Weems reference that may have been the same or earlier to your reference at:



directing you to page 397 which closely describes the decision making process I described,  Noting this is dated 1938 with the latest info at the time I would expect FN to be at or behind this level of technique, not using much that is found in your other references that date to 1940+.




directing you to page 397 which closely describes the decision making process I described,  Noting this is dated 1938 with the latest info at the time I would expect FN to be at or behind this level of technique, not using much that is found in your other references that date to 1940+.


JB
You find the same basic information in Weems, 1931 edition which I didn't have when I put up the website. Weems and Noonan were friends and Noonan contributed to the techniques found in the Weems manuals so there is no doubt that Noonan knew these techniques. Chichester used this procedure in 1931 crossing the Tasman sea in a Gypsy Moth biplane and he is given credit in the English speaking world for developing this technique but Portguese Admiral Coutinho used the same technique making the first flight across the South Atlantic in 1922. AFM 51-40 lays out the long history of this type of navigation so it was not something brand new in 1937.
gl
« Last Edit: July 05, 2012, 10:45:53 PM by Gary LaPook »
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Malcolm McKay

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #92 on: July 05, 2012, 11:05:33 PM »

Malcolm, are you speaking here specifically of the 'Box Search around 157-337 (search pattern / crashed and sank)' theory, or the 'Niku landing' theory?

What Jeff Victor has illustrated I believe has to do with the 'Box Search' and some attending conflicts that may be among the various assumptions about how that hypothesis comes together.

But the point is well made in any case and is, of course, always a valid concern.  Thanks!

LTM -

Just things in general as what applies with the box search idea seems to be the case with other things. Or put it this way, if TIGHAR come up with identifiable Earhart Electra wreckage this trip then the various ways of shoehorning ideas to fit proposals will become moot which will be a relief.   
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Malcolm McKay

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #93 on: July 06, 2012, 01:05:26 AM »


Well, I think there will always be enough ambiguity among the things-found and how they may have arrived that little, if anything, can be unequivocally 'proved' as to those articles, which I think is you main point (along with the point that professionally you don't care for scenarios that seem a bit too contrived for the evidence, etc.). ....

Of course Jeff the irony is that if some clearly identifiable wreckage is found off the reef then it still won't actually provide any proof that the artifacts that are part of the supporting evidence for the current hypothesis are Earhart's. The questions about them which have been discussed ad nauseum will still apply, but such a debate won't see me involved - getting far too old to care much about freckle cream bottles or compacts  ;D . Still if wreckage is found that is the Electra then that won't matter. We wait and see.
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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #94 on: July 06, 2012, 02:58:12 AM »

Gary,

Thanks for the point out to the background data.  It led me to this thread where it is now clearer to me what the overall debate is about.  I will admit to less expertise than is exhibited here but I will pose a caution to the debate.  In my time as an aviator (1983-2005) the USAF progressed from basic DR flying to basic spinning mass INS (lots of drift), to ring laser INS, to INS with Kalman filtered GPS, to embedded GPS/INS.  Most of that transformation occurred in a very short time (~1989-2001).  Your references are mostly post 1940 and much was learned during the war years as military aviation dramatically advanced the navigational knowledge.  I had seen a few of your references but not many but I had seen a Weems reference that may have been the same or earlier to your reference at:

JB
Things didn't change that quickly for navigators in WW2. They still used the same type of octant that Noonan used, they still used the same computation tables, H.O.208, still used the MK 2 driftmeter like Noonan used and the slightly different B-5 driftmeter that stuck out through a hole in the side of the plane, but the same computation methods were used. The only significant thng that changed for American oceanic flight navigators in WW2 was the introduction of LORAN-A late in the war. Everyting else stayed the same trough the '30s and '40s and the celnav was the same until the present century with B-52 navs still using the same techniques.

gl
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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #95 on: July 06, 2012, 04:31:20 AM »

-

I wouldn't discount some form of a brief search pattern where FN may have thought Howland should have been as part of the effort (and admittedly consider that most likely to have been a brief 'circling' or box pattern where Howland 'should have been' and a brief excursion to NNW along the LOP before turning to SSE as I see it). 


What you stated is what TIGHAR has been saying for year, search NNW for a bit then run SSE until fuel exhaustion.
My question to all of you is how far do you go NNW?

Let's start with the basics. From much experiece, celestial navigation fixes are taken to have a 10 NM radius of uncertainty and this is documented in all of the manuals, the regulations and Noonan said the same in a letter to Weems. Although it is possible to be outside this ten mile circle it is very unlikely and you are much more likely to be near the center of the circle than near the edge. Dead reckoning navigation has an uncertainty of 10% of the distance flown through the air since the last fix, not over the ground, so is related to true airspeed not ground speed. It is possible to be outside of this limit but that would be highly unusual and you are much more likely to be nearer to the DR position in the center than near the edge of the uncertainty area.

So let's see how this works out in practice. Assume that Noonan gets a normally accurate celestial fix at 1623 Z, at the time Earhart transmitted "partly cloudy" and they dead reckon to Howland from there without getting any sun shots with the sextant. Earhart reported being in the vicinity of Howland at 1912 Z, 2 hours and 49 minutes later. Cruising at 130 knots the plane flew 366 air nautical miles during this period making the uncertainty due to DR of 36.6 NM (37 NM.) Add to this the 10 NM uncertainty from the original fix makes the total uncertainty at 1912 Z 47 NM so the plane is unlikely to be outside a circle of 47 NM radius centered on their DR position over Howland making the whole area 94 NM across. See illustration in the attached PDF. Illustration 2 shows the 10% uncertainty area as it expands from the perimeter of the 1623 Z fix circle which is almost exactly a spread of 6° on either side of the course line.

So if this is all the information they have at 1912 Z, what should they do? The answer is to do an expanding square search pattern since, based on the information they have, they are equally likely to off in any direction. This is not exactly true because they are less likely to have flown directly over Howland and so be on the course line past Howland though it is possible, perhaps the island was obscured by a cloud at the wrong moment. What would be the best way to fly the search pattern? Fly the first leg straight ahead for twice the estimated distance you believe you should be able to spot the island or Itasca.

We have to be careful when we talk about "visibility" since it is used in two different senses. Itasca reported visibility of 20 NM or more. "Visibility" when used in this sense relates to the clarity of the air, how far away a large object such as a mountain can be seen, and is similar to the term "search visibility" as used in the Civil Air Patrol inland search manual. For planning a search pattern, "visibility" means how far away you can expect to spot the object you are searching for and is similar to the term "scanning range" as used in the CAP inland search manual. It is possible to confuse these terms. ;) so I will use this later term, as defined by the CAP, to avoid confusion. I think most of us have assumed that since Itasca reported 20 NM plus "visibility" that the island should have been spotted at that distance but I don't think that this is the case and that the "scanning range" was less. (I'll get to this in a later post.)

There is no reason to believe that Earhart knew the visibility being measured by Itasca and there is no way for us to know what "scanning range" Noonan would have used for planning his search. The choice of "scanning range" is very important because if you overestimate it then you plan and fly the search pattern with the legs too far apart which then causes un-searched gaps between the legs so you can miss your objective. On the other hand, if you use an estimate that is too low then it takes much longer to do the search making fuel a bigger problem.  A normal expanding square pattern with a scanning range of 20 NM will search a square 120 NM across with 5 legs totaling 360 NM and would cover the original circle of uncertainly around the DR position over Howland. This would take 2 hours and 46 minutes. I have attached a diagram of this search, each square is 10 NM and the circle of 47 NM radius is the original area of uncertainty. The plane approaches the position of Howland from the bottom on the diagram and searches 20 NM on both sides of this approach track. When their DR shows them over the position of Howland they start the search pattern with the first leg straight ahead for double the scanning range so they go 40 NM and then turn left. This allows them to scan 20 NM on either side as indicated in pink. The second leg is also 40 NM followed by two legs of 80 NM and the 5th leg is 120 NM.

If you assume a scanning range of only 10 NM then it will take 9 legs to search the original circle of uncertainly, totaling 500 NM taking 3 hours and 51 minutes and you will only have searched a square 100 NM on a side. So it takes one extra hour to search the original uncertainty circle with an assumed "scanning range" of 10 NM compared to 20 NM.

(To be continued.)

gl
« Last Edit: July 08, 2012, 12:47:30 AM by Gary LaPook »
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Martin X. Moleski, SJ

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #96 on: July 06, 2012, 09:09:39 AM »

Dunno, it can't all fit, I have to agree.  But as to spotting Howland - take a look at the island from a few miles out as recorded by the Waitt search effort - same time of day and I believe very possibly similar sky conditions.

I think that we know what the sky conditions were on 2 July 1937 at Howland from the deck log of the Itasca and from other accounts as well.

9 = Prominent objects visible above 20 miles.

3/10 of the sky covered by cumulus clouds.

James Christian Kamakaiwi: "We watched the sky, hoping to pick the plane out against white cumulus clouds which were all around the horizon."

The 1937 Search: The First 24 Hours": "But sometime in the next few minutes Thompson changed his mind and became convinced that Earhart was not still aloft but was, in fact, already down at sea. At 10:40 (22:10 GCT) he abandoned his station at Howland (after having just told San Francisco he would stay there until noon) and steamed off to the northwest. He indicates in his Radio Transcripts that this was the only area within visual range of the Itasca that had any cloud cover, and would be the most likely place for Earhart to be, as she could not see either the island or Itasca."

So far as I know, we don't have any photos or commentary from people approaching Howland under such good visibility. 
LTM,

           Marty
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JNev

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #97 on: July 06, 2012, 12:46:02 PM »

'Vis' might not have been the problem as much as the shadows, IHMO.

"3/10 of the sky covered by cumulus clouds" isn't far off from what we can see in the modern photo example.

Quote
James Christian Kamakaiwi: "We watched the sky, hoping to pick the plane out against white cumulus clouds which were all around the horizon."

Ouch (ref: Howland / cloud shadows picture).

LTM -
- Jeff Neville

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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #98 on: July 08, 2012, 01:08:45 AM »


What you stated is what TIGHAR has been saying for year, search NNW for a bit then run SSE until fuel exhaustion.
My question to all of you is how far do you go NNW?

Let's start with the basics. From much experiece, celestial navigation fixes are taken to have a 10 NM radius of uncertainty and this is documented in all of the manuals, the regulations and Noonan said the same in a letter to Weems. Although it is possible to be outside this ten mile circle it is very unlikely and you are much more likely to be near the center of the circle than near the edge. Dead reckoning navigation has an uncertainty of 10% of the distance flown through the air since the last fix, not over the ground, so is related to true airspeed not ground speed. It is possible to be outside of this limit but that would be highly unusual and you are much more likely to be nearer to the DR position in the center than near the edge of the uncertainty area.

So let's see how this works out in practice. Assume that Noonan gets a normally accurate celestial fix at 1623 Z, at the time Earhart transmitted "partly cloudy" and they dead reckon to Howland from there without getting any sun shots with the sextant. Earhart reported being in the vicinity of Howland at 1912 Z, 2 hours and 49 minutes later. Cruising at 130 knots the plane flew 366 air nautical miles during this period making the uncertainty due to DR of 36.6 NM (37 NM.) Add to this the 10 NM uncertainty from the original fix makes the total uncertainty at 1912 Z 47 NM so the plane is unlikely to be outside a circle of 47 NM radius centered on their DR position over Howland making the whole area 94 NM across. See illustration in the attached PDF. Illustration 2 shows the 10% uncertainty area as it expands from the perimeter of the 1623 Z fix circle which is almost exactly a spread of 6° on either side of the course line.

So if this is all the information they have at 1912 Z, what should they do? The answer is to do an expanding square search pattern since, based on the information they have, they are equally likely to off in any direction. This is not exactly true because they are less likely to have flown directly over Howland and so be on the course line past Howland though it is possible, perhaps the island was obscured by a cloud at the wrong moment. What would be the best way to fly the search pattern? Fly the first leg straight ahead for twice the estimated distance you believe you should be able to spot the island or Itasca.

We have to be careful when we talk about "visibility" since it is used in two different senses. Itasca reported visibility of 20 NM or more. "Visibility" when used in this sense relates to the clarity of the air, how far away a large object such as a mountain can be seen, and is similar to the term "search visibility" as used in the Civil Air Patrol inland search manual. For planning a search pattern, "visibility" means how far away you can expect to spot the object you are searching for and is similar to the term "scanning range" as used in the CAP inland search manual. It is possible to confuse these terms. ;) so I will use this later term, as defined by the CAP, to avoid confusion. I think most of us have assumed that since Itasca reported 20 NM plus "visibility" that the island should have been spotted at that distance but I don't think that this is the case and that the "scanning range" was less. (I'll get to this in a later post.)

There is no reason to believe that Earhart knew the visibility being measured by Itasca and there is no way for us to know what "scanning range" Noonan would have used for planning his search. The choice of "scanning range" is very important because if you overestimate it then you plan and fly the search pattern with the legs too far apart which then causes un-searched gaps between the legs so you can miss your objective. On the other hand, if you use an estimate that is too low then it takes much longer to do the search making fuel a bigger problem.  A normal expanding square pattern with a scanning range of 20 NM will search a square 120 NM across with 5 legs totaling 360 NM and would cover the original circle of uncertainly around the DR position over Howland. This would take 2 hours and 46 minutes. I have attached a diagram of this search, each square is 10 NM and the circle of 47 NM radius is the original area of uncertainty. The plane approaches the position of Howland from the bottom on the diagram and searches 20 NM on both sides of this approach track. When their DR shows them over the position of Howland they start the search pattern with the first leg straight ahead for double the scanning range so they go 40 NM and then turn left. This allows them to scan 20 NM on either side as indicated in pink. The second leg is also 40 NM followed by two legs of 80 NM and the 5th leg is 120 NM.

If you assume a scanning range of only 10 NM then it will take 9 legs to search the original circle of uncertainly, totaling 500 NM taking 3 hours and 51 minutes and you will only have searched a square 100 NM on a side. So it takes one extra hour to search the original uncertainty circle with an assumed "scanning range" of 10 NM compared to 20 NM.

(To be continued.)

gl
An interesting thing happens as you continue to draw the search pattern. It turns out that starting with a circle of uncertainty with a radius of 47 NM and a scanning range of 20 NM that you will never search the entire area were is is possible for the search object to be. This is because the circle of uncertainty grows faster than the plane can search it. The 10% DR uncertainty continues while the search is being conducted. After five legs the plane has searched the original 47 NM radius circle of uncertainty but the plane has flown 360 NM to do it. Ten percent of this is 36 NM which must be added to the original 47 NM radius so the circle of uncertainly has grown to a radius of 83 NM at this point and there are areas that have not been searched near the edges of this circle, see attached diagram. If this is hard for you to get your head around then another way to conceptualize this is to think of the plane having perfect navigation with GPS but the search object is a life raft that is not perfectly located and has an uncertainty of 47 NM at the start of the search and is subject to currents of up to 13 knots in any direction. So after flying those first five legs, the raft might have drifted an additional 36 NM outside the original circle in the 2:46 spent so far in the search so now the circle is 83 NM in radius. The search has scanned the highest probability area near the center of the circle so might have found the raft but if the raft had actually been near the edge of the 47 NM circle at the start then it could have been missed if the current moved it further away from the center, outside the original search area. If you continue to draw the search pattern you find that you never can get ahead of the ever growing circle. It works out that with a scanning range of 20 NM then the original uncertainty must not exceed 24 NM or you end up in this situation. It is even worse if the scanning range was 10 NM because it would take flying 500 NM and 3:51 so the circle would grow by 50 NM to a 97 NM radius instead of just the additional 36 NM in the prior example.

gl
« Last Edit: July 08, 2012, 02:20:31 PM by Gary LaPook »
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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #99 on: July 08, 2012, 04:17:52 AM »

Now let's look at the TIGHAR theory, that Noonan observed the sun as it rose, developed a line of position from this observation, advanced this LOP until it passed over Howland, measured the distance that needed to be flown by DR until intercepting that LOP, compute the time necessary to fly this distance based on their known ground speed, fly for the computed time, turn left and search NNW at the computed time of the intercept of the advanced LOP for a certain distance, make a 180° turn and search the other way along the LOP, and then continue to the SSE until finding Gardner. My question is "how far do you search to the NNW before turning around?"

I have attached illustrations of this theory. The first image shows the presumed fix at 1623 Z, the 10 NM circle of uncertainty around it. Based on the report at 1912 Z the plane would have flown 366 NM in this period after the fix. If no sun line LOP were obtained then, if navigating solely by DR, the uncertainty would grow by 37 NM making the uncertainty circle around Howland 47 NM in radius, 94 NM in diameter.  The second illustration shows that the uncertainty grows at 10% of the distance flown, starting from the circumference of the circle around the starting fix.
Sunrise at sea level at Howland was at 1745 Z and at 10,000 feet above Howland, ten minutes earlier at 1735 Z. By allowing for the rotation of the earth and the movement of the plane (I won't go into the details of this computation) we can calculate that at 10,000 feet they would have observed the sun peeking up from behind the horizon at 1749 Z. This is 1:26 minutes after the fix and the plane would have flown 147 NM in this time so the DR at the time of sunrise is plotted on illustration 3 along with the circle of uncertainty which has grown to a radius of 29 NM. There remains 179 NM to fly to Howland. Illustration 4 shows the sunrise LOP which runs 157° - 337° true and illustration 5 shows the plus and minus 7 NM uncertainty band. The aircraft would have to be located in this band and bounded on the north and south by the circle of uncertainty, somewhere along the 58 NM of the 14 NM wide band inside the circle. Illustration 6 shows this LOP advanced to 1912 Z and the uncertainty grows by 10% of the 179 NM covered, 18 NM, which is added to the original uncertainty of 7 NM making the uncertainty at 1912 Z of plus and minus 25 NM, a band 50 NM wide shown in illustration 7. The aircraft is within this 50 NM wide and 94 NM long band. With an uncertainty of 25 NM, the advanced sunrise LOP is not sufficiently accurate to assure finding Howland since this exceeds the visibility and the scanning range.

(I have said for ten years that it was not possible to take a "sunrise observation" for technical reasons and the current example shows yet another reason why it would be useless to take an observation when so far away from the destination which results in such a large DR uncertainty that the resulting LOP is of no use.)

Now, according to TIGHAR, they turn and fly NNW along the LOP, so how far must they go? They must go at least the 47 NM of the circle of uncertainty but after flying those 47 NM the uncertainty has grown by an additional 4.7 NM (call it 5 NM) so the plane must go at least 52 NM. At the same time the width of the band has also grown by the same 5 NM in each direction make the band 60 NM at the end of the NNW leg. Illustration 8 shows the area that must contain the airplane, 60 NM wide and now extends 52 NM NNW from the presumed location of Howland.

The plane now turns around and proceeds SSE, how far will it go in this direction? It must go 52 NM back to the starting position plus the 47 NM to the edge of the original circle plus 10 more NM to account for the increase in the DR uncertainty on this leg, a total of 109 NM placing the DR position at the end of the SSE leg 57 NM from Howland, 19 NM from Baker and 300 NM from Gardner. This leg also adds 11 NM on each side of the LOP making it now 82 NM wide, 41 NM on each side and absolutely useless for finding Howland. Illustration 8 shows this and the area that contains the plane at the end of the SSE leg. Noonan knows at this point that he must be SSE of Howland, most likely about 57 NM but with a range of zero to about 115 NM so he is certain the the closest land is Howland and Baker and the next nearest land in the Phoenix islands is at least 230 NM away and more likely about 300 NM away.

So what should they do at this point? Go back to the NNW until their DR shows them close to Howland and then do the expanding square search pattern. It makes no sense to continue further to the SSE where they would have to rely only on luck to stumble onto one of the very scattered islands in the Phoenixs. Proceding in that direction would use all or most of their remaining fuel and they would not be able to do any search pattern in the vicinity of those islands for the simple fact they would have no way to determine that they had gone far enough. The uncertainty in their DR at this point where they had to make their decision is fully 82 NM wide and 115 NM long and their DR accuracy will only get worse on the way to the Phoenixs which is why you can't dead reckon to a destination if you are not starting from an accurate fix. In fact, considering the 50 NM wide band of the LOP at 1912 Z which made the uncertainty similar along both axes, it would have made more sense to ignore the stale LOP all altogether and just start the search pattern at 1912 Z as I have shown in my prior posts and this would have save about 1:40 of fuel that could be used for the search.

gl
« Last Edit: December 13, 2012, 09:28:53 PM by Gary LaPook »
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John Ousterhout

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #100 on: July 08, 2012, 10:03:41 AM »

Gary,
Great analysis.  If I understand you correctly, the expanding circle of uncertainty can be thought of as growing at 13 knots.  Yikes!  It's as though the island started moving in some unknown direction at 13 knots, starting the moment of Fred's last accurate position, and keeps on moving at 13 kts even when a search pattern is being flown.  That's in addition to the initial uncertainty.
 
Imagine taking off from your local airport for a relaxing afternoon of sight seeing.  An hour later, your airport has moved 13 miles from where you last saw it, and you don't know what direction it went.  So you initiate a search pattern, but the airport is still moving at 13 mph, somewhere, in some direction, while you search for it.   To make things even worse, any alternative airports have also been moving in random directions at 13 mph since takeoff.  This sounds like a nightmare!  The only way to reduce the size of the circle of uncertainty is to obtain another fix.

Have I got that right?
Cheers,
JohnO
 
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Jeff Victor Hayden

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #101 on: July 08, 2012, 10:20:32 AM »

Good work Gary and thanks for the info on the CofG.
What is the role of FN in the search pattern? Is he plotting the positions, calling out the course changes and plotting the areas covered so far or, trying to look out of both the windows at the back of the plane to try and locate Howland. I read in another post that 2 sets of eyes are better than one when working a search pattern and, the best place for the 2 sets of eyes to be to achieve this is the cockpit, best all round visibility.
This must be the place
 
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Martin X. Moleski, SJ

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #102 on: July 08, 2012, 11:34:56 AM »

I have said for ten years that it was not possible to take a "sunrise observation" for technical reasons and the current example shows yet another reason why it would be useless to take an observation when so far away from the destination which results in such a large DR uncertainty that the resulting LOP is of no use.

OK.  Then where did the line 337-157 come from?
LTM,

           Marty
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Gary LaPook

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #103 on: July 08, 2012, 12:22:50 PM »

I have said for ten years that it was not possible to take a "sunrise observation" for technical reasons and the current example shows yet another reason why it would be useless to take an observation when so far away from the destination which results in such a large DR uncertainty that the resulting LOP is of no use.

OK.  Then where did the line 337-157 come from?
That's the next installment, stay tuned.

gl
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William Thaxton

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Re: LaPook Hypothesis: Box Search around 157-337
« Reply #104 on: July 08, 2012, 05:25:06 PM »

Go away for a couple of weeks and look how many writers come over to the dark side!  Seriously, though, good job in describing a box search and the reasons for executing such.  While we disagree on a couple of points, the general thrust of your presentation is one I can readily support.

I'm still surprised at the number of writers who seem to think that (1) it is somehow "presumptive" to think a trained and experienced navigator would act in a manner that is not in accordance with his/her training and (2) that all knowledge of navigation has been gained post-WWII.  For me, the more cogent question is "Why would AE/FN abandonestablished "best practices" and head off looking for a flyspeck in the broad Pacific?"  Such a thing COULD have happened but if it did we need a "why".

William
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