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Author Topic: FAQ: Colorado / Lambrecht Search, 9 July 1937  (Read 446649 times)

Malcolm McKay

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #135 on: June 27, 2012, 10:48:13 PM »

   This is just one scenario, of what I would think should be very many scenarios, that better answers the question about how the artifacts got to the seven site, than the Amelia Earhart as the castaway of the seven site theory does.

etc................     

Yes entirely likely and something I have consistently argued in regard to what the recovered artifacts at the Seven Site actually indicate. However all I received was abuse - perhaps you will have better luck.
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #136 on: June 28, 2012, 12:51:08 AM »

Gary, since you like to work with numbers so much, you might find this document, Compatibility of Land SAR Proceedures with Search Theory , interesting.

Especially note the conclusions on pdf pages 78, 79 (pgs 72, 73 of the document) which says in part, "In short, none of the POD estimation procedures found in the land SAR literature are compatible with search theory and none can be modified to make them compliant with search theory".

It is a nice criticism of the land POD tables in the National Search and Rescue Manual but gives no additional information itself to come up with different and more accurate search methods or better calculation of POD. The "sweep width" method that is advocated in this paper is used in the maritime search portion of the manual but not in the land search portion. You might also note that its recommendations have NOT been implemented in the revised and current Manual available here. and that the POD tables I posted in the past are identical to those in the revised and current manual.

Also, nowhere in this nearly 200 page document is there any claim the current inland POD tables overestimate the POD which appears to be your complaint. The document only discusses theoretical, mathematical methods of developing search methodologies and only faults to POD tables for not having been developed by use of that theoretical method.


 So, I have asked before, does anybody have any better official documentation showing POD for searches conducted over Gardner? Until someone comes up with such a document then the current SAR manuals must be taken as authoritative on this question.

gl
« Last Edit: June 28, 2012, 02:18:50 AM by Gary LaPook »
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #137 on: June 28, 2012, 01:01:24 AM »

Gary, here we go again. First of all let me again point out that your experiment was accomplished over flat terrain with no overhead cover.
What I saw is the same thing that Lambrecht would have seen if Earhart had been on the beach on Gardner so as to that scenario my data is certainly valid. I gathered some data, I do not claim that it is a complete study of search effectiveness. As to the people in the field, I stated: "The crops are a little more than waist high so the vegetation is nowhere as difficult as that on Gardner" so I never claimed that it did replicate the situation on Gardner with overhead cover.
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Second of all let me refer to your oft quoted "Land Probability of Detection Tables", on page 77 of the pdf copy of the National Search and Rescue Supplement, see below. Please note what it says in Para 5.5.1 "The following POD tables used by the CAP and Air Force assume a crash location is more difficult to see in heavy terrain, and the search object is relatively small, such as a light aircraft". I think this is quite clear that the POD's listed are for, at a minimum, a light aircraft and not people.
I posted this before:

"The Search and Rescue Manual states that searching for persons is the second most common type of search yet there is no separate POD table for this type of search or any correction table to use in adjusting the published values for POD as would be necessary if your interpretation was correct, that the tables only apply to searches for downed aircraft. I have stated before that the people who drafted this manual were compelled to use conservative numbers so as not to overestimate the effectiveness of a search. So, if the values only applied to searches for aircraft and the same tables also had to be used for searching for people then, if the calculated POD was designed to apply to aircraft, then the numbers would overestimate the effectiveness of a search for a person and so would NOT be conservative. But, if instead, they assumed the worst case, that of searching for the more difficult object to find, a person, then the tables correctly, and conservatively, predict the quality of a search for a person and underestimate the effectiveness of a search for a larger object. The is a conservative way to draft the POD tables. So which one makes more sense when drafting this table, overestimating the effectiveness of a search for a person or underestimating the the effectiveness of a search for a larger object? Which would be more conservative? Which would result in more lives being saved?
My National Search And Rescue Manual is dated 1986. You referred us to a CAP document dated 2005. In spite of almost 20 additional years of search experience the POD table in your 2005 document is identical to the table in the 1986 manual. There is no separate POD table for searches for people nor is there a table to make an adjustment for searches for persons even though many thousands of such searches must have been made in this period. It appears that the drafters of the 2005 document were satisfied with the existing POD tables. "

I also note that this 2005 CAP manual was drafted after the document you directed me to in your prior post that criticized the inland POD tables and the CAP chose NOT to make a change to these tables.
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Third of all let me point out the clothing that AE and FN were wearing in most of the pictures made of them. AE is usually shown wearing either khaki or very dark trousers, either of which tends to blend in with most backgrounds, plus a plaid blouse which would show up very well most anywhere but would be a rather small target. FN is almost always shown wearing dark blue or black trousers and shirt which again would tend to blend in with most backgrounds.

http://earchives.lib.purdue.edu/u?/earhart,904 

And lastly, the SAR documents always talk about the condition of the crews as being critical to detection of crash sites. While it does not talk about the attitude or attentiveness of the other crews, check out what Lt(jg) William Short had to say about the search in his log/letter to his father about the search. Especially note his comments about the search in general in his July 5, 1937 entry and the specific comments about the Gardner Island search on July 9, 1937. He gives a good discription of the ship on the reef but apparently fails to even notice the Buka trees on the atoll.

http://tighar.org/Projects/Earhart/Archives/Forum/Highlights21_40/highlights26.html


gl
« Last Edit: June 28, 2012, 01:30:34 AM by Gary LaPook »
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #138 on: June 28, 2012, 01:36:16 AM »


Gary, I know you have very good eyes, but would you be so good as to give us an estimate of the apparent altitude in your photos when they are brought up on your post. I do not have Google Earth so I cannot zoom in on what you are showing.
I don't know how to do that, I just zoomed in or out until what I wanted to show fit in the frame.

gl
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #139 on: June 28, 2012, 02:02:28 AM »

   This is just one scenario, of what I would think should be very many scenarios, that better answers the question about how the artifacts got to the seven site, than the Amelia Earhart as the castaway of the seven site theory does.
   
   All the artifacts that we have found at the seven site could easily have gotten there without the existence of a  castaway. 
 occam’s razor ?
Tom King made much out of the many clam shells found at the seven site because they had not been opened in the native fashion but in the standard American fashion so Eahart must have been a castaway opening those clam shells. I was born and raised in Chicago and I have no idea of how to open a clam shell, American or otherwise. Amelia was born and raised in Atchison Kansas, just down the street from Chicago, so why would anybody think she knew the standard American way to open a clam? But of all those Coasties, I'll bet that some were from New England so it is much more likely that it was the Coasties that had the traditional Down East Clam Bake at the seven site than Earhart.

gl
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Andrew M McKenna

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #140 on: June 28, 2012, 02:06:40 AM »

This may be a trivial question, but does Niku even have rocks?  Or chunks of coral that would substitute for rocks?

Nikumaroro does have rock in the sense that coral gets cemented together into "beach rock".  If you remove the coral rubble from the beach on the seaward side you end up with beach rock underneath.  Generally, anywhere along the shoreline of the lagoon where there is not a sandy beach you will find a ledge of beach rock.  This is not volcanic as you might think, it is made up of calcium carbonate (think coral and shells) and is usually quite jagged.  The sun seems to turn it dark as you see.  You don't walk on this stuff barefoot unless you have a lifetime of callus built up.  It tends to break apart in layers, so you end up with flat stones and we see them in use for property markers in the Village and they were used to build the fish trap.

Photo attached.

amck

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C.W. Herndon

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #141 on: June 28, 2012, 06:40:46 AM »


Gary, I know you have very good eyes, but would you be so good as to give us an estimate of the apparent altitude in your photos when they are brought up on your post. I do not have Google Earth so I cannot zoom in on what you are showing.
I don't know how to do that, I just zoomed in or out until what I wanted to show fit in the frame.

gl

Gary, In the lower right hand corner of your Google Earth maps is a note that says "eye altitude.........ft". On your first map the altitude is given as "23,364" feet. On the second it is "13,236" feet. I just thought this information might help everyone understand why they could not see what you did.
Woody (former 3316R)
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Malcolm McKay

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #142 on: June 28, 2012, 06:50:07 AM »

... so why would anybody think she knew the standard American way to open a clam? But of all those Coasties, I'll bet that some were from New England so it is much more likely that it was the Coasties that had the traditional Down East Clam Bake at the seven site than Earhart.

gl

Yes to me that seems just as likely. The Seven Site has far too much traffic over the period of the island occupation to draw too much inference from the way clams are opened.
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Tom Swearengen

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #143 on: June 28, 2012, 07:27:59 AM »

Woody---I doubt that Gary was at 23000 feet. I suspect when he transposed his flight data onto Google Earth, he need to expand the map to get the data included, thus the higher indicated altitude from GE. my 'guess' But if he WAs at 23000, he has better eyes than I do!!
Tom Swearengen TIGHAR # 3297
 
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C.W. Herndon

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #144 on: June 28, 2012, 07:59:49 AM »

Tom, Gary said he was flying at 1000ft but what we are looking at in the pictures from Google Earth is what it looks like from the altitudes indicated (23,364ft and 13,236ft). Nothing like Gary was seeing on his flight. He was only showing the route he followed.

Needless to say you are not going to be able to see people on the ground at the altitudes indicated. That was my point. I guess I didn't make that very clear.
Woody (former 3316R)
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C.W. Herndon

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #145 on: June 28, 2012, 09:15:06 AM »

Gary, here is, for your edification, a link to the latest version of the LAND SEARCH AND RESCUE ADDENDUM to the National Search and Rescue Supplement to the International Aeronautical and Maritime Search and Rescue Manual, Version 1.0, November 2011.

http://www.uscg.mil/hq/cg5/cg534/nsarc/Land_SAR_Addendum/Published_Land%20SAR%20Addendum%20(1118111)%20-%20Bookmark.pdf
Woody (former 3316R)
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #146 on: June 28, 2012, 11:03:11 AM »

Gary, here is, for your edification, a link to the latest version of the LAND SEARCH AND RESCUE ADDENDUM to the National Search and Rescue Supplement to the International Aeronautical and Maritime Search and Rescue Manual, Version 1.0, November 2011.

http://www.uscg.mil/hq/cg5/cg534/nsarc/Land_SAR_Addendum/Published_Land%20SAR%20Addendum%20(1118111)%20-%20Bookmark.pdf
Thanks for the link and I will read it with much expectation later today! The prior links you posted only took me to the 2001 version and claimed that that was still the current version and the other link went only to the 2005 CAP document. I have spent a lot of time with the maritime search provisions of the 1986 National SAR Manual that does use the "sweep width" method of figuring POD which does make sense. I am interested to see if in the 2011 manual it manages to apply that concept to inland searches as this deals with the problem, that I pointed out on many occasions, that the prior inland search guidance did not deal with the issue of the type of object being sought, a person, a plane, a car...( I wish you had posted this link yesterday so that I would not have had to read through that other 200 page document :P

gl

« Last Edit: June 30, 2012, 04:02:50 AM by Gary LaPook »
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C.W. Herndon

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #147 on: June 28, 2012, 11:48:17 AM »

Turn about is fair play and I owe you one more so watch out!
Woody (former 3316R)
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« Last Edit: June 28, 2012, 11:49:50 AM by C.W. Herndon »
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Gary LaPook

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #148 on: June 28, 2012, 02:48:22 PM »


Since we have hotly debated on this thread and others the distances that searchers could see people on the ground, I decided to do a test. I went flying today in a Skycatcher and one of my projects for this flight was to see how far away I could see people on the ground. I have attached two Google Earth images of portions of the flight, the red line is the track of my plane which is recorded every five seconds by one of my GPS. (This was not the entire purpose of my flight and you can see the entire flight track by looking at the third attached GE image.) I had no preconceived idea of what I would find. The first image shows my flight offshore of Ventura California. I was flying towards the south at 1,000 feet and looking towards the beach to see if I could spot people on the beach. I planned to fly closer and closer until I could recognize people, note a prominent landmark near the people that I could spot on Google Earth, and push the button on my second GPS to record my location at the point where I detected the people and this worked out well.  From my position offshore I could see people clearly on the section of the beach between the breakwaters. Then I downloaded the GPS data to my computer and used it to to locate my plane on GE and then measured the distance to the people I saw on the beach near the landmark. I was surprised that the distance was so great, 2.48 NM! Later I flew along a road and looked for workers in the fields nearby along with landmarks near them so that I would be able to accurately place them on GE. The second image shows that I could see field workers at a distance of 0.89 NM but it is also possible that if there had been workers farther away that I would have been able to see them at an even greater distance. The crops are a little more than waist high so the vegetation is nowhere as difficult as that on Gardner but it was an interesting test anyway since only the tops of the workers' torsos were visible and yet it was not difficult to see them at close to a nautical mile away.

gl

Another purpose for the flight was to take some celestial observations. I chose the day so that the sun and moon would be properly placed to allow getting a fix, unfortunately I didn't allow for the sun being so high, 79°, and the cabin roof prevented getting any sun shots. I did take two observations of the moon, one each with the MA-2 and the A-7 bubble octants. I took ten shots with the A-7 and the average altitude was 17°54' which produced an intercept (error) of 5.7 NM away from my GPS position. I did a two minute average with the MA-2 and the altitude was 20° 00' which produced an intercept (error) of 6.4 NM away from the actual GPS at the time the observation was taken. (This is labeled as "toward" since it was toward the direction of the moon.)

I'm pretty happy with these results because keeping the plane in steady flight is critical for accuracy and I was flying solo without an autopilot so I had to put the plane on heading, level the wings, line up the moon in the octant for a few seconds, check to see if the wings were still level and straighten them up back on heading if necessary, observe the moon for a few more seconds, repeat... plus there is always the problem using the moon when it is not full since you have to estimate where the center of the moon should be and place that in the center of the octant's bubble.

So 6 NM accuracy with all those impediments which is within the expected 7 NM uncertainty of bubble octant observations taken in flight was quite satisfying.

See the attached plots. The red line is the track of the plane as recorded by my GPS

gl
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C.W. Herndon

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Re: FAQ: Colorado / Lambrecht Search, 9 July 1937
« Reply #149 on: June 28, 2012, 03:02:39 PM »

No wonder you weren't any more accurate. Look at all that turning you did. LOL

Sounds like you haven't completely lost your touch.
Woody (former 3316R)
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