I was disappointed that Bob feels that charting the Great Circle course is a tedious and time-consuming task --- and, moreover, that (not having done it) he knows that it would produce "no useful information in this case." I am one of those people who think that one should decide whether or not information is "useful" after one acquires it --- and that all information is "useful" so long as it is accurate and tells us something about the subject.

In fact, it's really not so difficult (these days) to get a rough idea of the great circle track (though perhaps without the precision that Bob's calculations would have provided). Take the latitude/longitude coordinates (I got them from the USGS map list and used 37-45 N and 122-15 W for Oakland and 21-15 N and 157-46 W for Honolulu --- obviously, different parts of the cities have different coordinates, but these are accurate enough for us.) Go to www.info.gov.hk/marden for a Great Circle calculator, enter the points of origin and destination, and printout the latitude readings for the Great Circle at 5 degree increments of longitude (or for each degree, if you wish more precision than we're going to use). (Elapsed time = 15 minutes.)

Now buy a sheet of ordinary 5x5 graph paper. Mark each 5 degrees of longitude at one inch intervals along the top, and each 5 degrees of latitude on the side. Each square on the paper is now equal to one degree (and is a perfect Mercator projection! ) Place dots representing Oakland and Honolulu. Connect those two dots with a straight line. You now have a graphic representation of the rhumb line course. Elapsed time = 10 minutes.

Go back to the waypoint latitude information you copied from the Great Circle calculator. Enter the latitude of the Great Circle on the chart as a dot at each 5 degrees of longitude (or more often, if you wish) - you now have a visual graphic representation of the variation in latitude between the great circle and rhumb line courses. (5 minutes.)

Since each 1/5 inch square on the chart equals one degree of latitude, and since one degree of latitude equal 60 nautical miles, one can visually estimate the distance of the Great Circle north of the rhumb line as:

at 125 W = 30nm
at 130 W = 60nm
at 135 W = 90nm
at 140 W = 120nm
at 145 W = 70 nm
at 150 W = 30 nm
at 155 W = 30 nm

The numbers are imprecise, of course -- the pencil line covers maybe 6 miles -- but they're interesting, aren't they? Unless I have made some major error in calculation or method, they show that Bob's assertion that "the great circle and rhumb tracks between Oakland and Honolulu are nearly coincident" is just plain wrong. (The tracks ARE nearly the same length -- 17 miles difference is right -- BUT THEY ARE WIDELY DIVERGENT, as much as 120 nautical miles.)

Bob's statement that Noonan was not attempting to follow a great circle, because "to navigate via a great circle requires making an infinite number of course changes at infinitely small time interval, and therefore is not practical ... clearly impossible," is a sort of navigational restatement of Zeno's paradox. The arrow strikes the target despite Zeno --- and a great circle course can be approximated, as indeed Lindbergh intended to do.

I don't know what to make of Bob's assertion that "Noonan's actual track shows THAT HE WASN'T ATTEMPTING to fly either a great circle or a rhumb track." What course was he attempting to fly? (And if you don't know, how can you criticize him for not being on it?)

I don't know whether FN was trying to fly a great circle or trying to fly a rhumb line or just wandering around hoping to bump into something. What I can't understand is the unwillingness to explore all the possibilities. I had hoped that I could persuade Bob to undertake the task of expanding his work so that we might all see whether the position of the great circle course (and -- mutatis mutandis -- the apparent similarity of the GUBA's navigation and flight track) might teach us something.

I once fired a surveyor because he persistently failed (on purpose, I thought) to show both the Northern and Southern boundaries of a piece of property on the same plat. Only if all the information is placed in graphic relationship will the non-experts among us be able to interpret as easily as you and Bob seem to be able to do. You may be intuitively (or reflexively) correct -- but I'd like to see it for myself.

I am sending you a copy of my very rough sketch showing the divergence between great circle and rhumb line courses to use as you wish. I shall enclose an extra copy for Bob.

Thanks.
Oscar

And I'll send you a printed copy of Bob's chart.

Concerning Japanese military in 1937, I have a document that might be of interest.

Department of State
Division of Far Eastern Affairs
5 July 1937
Subject: Search for plane of Amelia Earhart

Mr. Hayama informed Mr. Ballentine over the telephone that the Japanese Embassy had received an urgent telegram from Tokyo asking that inquiry be made of this Government whether the Japanese Government could be of assistance in connection with the search for Amelia Earhart, in view of the fact that Japan had radio stations and warships in the Marshall Islands... Mr.Ballantine expressed his appreciation etc.

The significance is that the Japanese did have warships in the Marshall islands on 5 July 1937.

Marty Moleski wrote:

> If Fred had wanted to use fixes from three or
> more celestial bodies after sunrise, he could
> have. He was just being lazy and careless.

It's been awhile since I last put in my two cents, but I feel that I have to ask some grounding questions here before everyone comes to the (rather pointless actually) conclusion that Fred Noonan "messed up" and therefore the flight didn't make it.

Just reading this through and thinking about the flight, I just don't buy "lazy and careless". I don't see how anyone, facing the most difficult navigational challenge of the trip, would just shrug and say, well, I'm too lazy to work on this, afterall, my own DEATH is the only risk here.

Also, wasn't it written somewhere that Fred Noonan spent hours checking and rechecking his watch (and didn't he have multiple watches)? Or wasn't it in one of the reports that he spent hours pacing, thinking through this leg of the trip, but then later seemed to be very pleased, as if he had come up with a good solution. Again, this is just not the profile of someone who is "lazy and careless".

Ric wrote:

> What we're finding out about ol' Fred is that, as a rule, he does not seem to
> have worried too much about staying smack on track and, when the DF bearing
> didn't happen, he could have found himself in a pickle.

As for staying "smack on track", you take a star shot from time to time, then order course corrections and give it a bit of time to sort out winds, etc. Taking shot after shot every ten to fifteen minutes would be pretty pointless.

The key would be the last set of shots just prior to dawn. And in that regard, given the range of the equipment wouldn't he have already worked out that the DF wasn't working at that point? In any case, he surely would have had the sense to get a good position from three or more star shots (conjecture) prior to dawn.

To me, the terms, "We must be on you..." seem to imply that they felt that they thought they knew pretty much within a fairly limited number of miles where they were. Given that the DF was inoperative, that could have only come from some pretty good star shots, yes?

Thomas Van Hare

I'm not sure that the Fred-must-have-known-the-DF-wasn't-working argument holds water. The flight had two possible systems for getting DF guidance:

1. They could transmit a signal upon which Itasca would take a bearing and them tell them what direction to fly.
2. They could take a bearing on signal transmitted by Itasca using their own loop antenna.

LTM,
Ric

A couple of lifetimes ago, I flew aircraft utilizing equipment which, in some ways, was quite similar to that available to Fred in 1937. We had two additional items not available to Fred: a drift meter and Loran. Both had limitations. Obviously, the optical drift meter could only be utilized when the ground (or water) was visible. I recall that Loran was sometimes helpful, but its credibility with navigators was no better than a mediocre three-star shot taken in turbulence. The bottom line, our primary navigation over remote areas--including the North Atlantic--consisted of Dead Reckoning, map reading, celestial (including sun LOP and "noon-day" fix, and radio bearings.

Our navigators plotted and flew a course that approximated a Great Circle. Just as you don't fly a DME arc in a constant shallow turn, we flew a single-heading course from point to point with a course change every 2-3 hours (360-520 nm). Lambert Conformal was the only type chart I remember using.

Interestingly enough, it wasn't until the introduction of the Laser Ring Gyro that airplanes could RELIABLY find an island the size of Howland without radio aids. The Inertial Navigation System used through the 60s and 70s on airplanes such as the DC-10 and 747 would sometimes exhibit startling errors. Allowable drift on these units was 3 plus 3 nm per hour of flight. Therefore, if our duo had an INS on board, they still could have missed Howland by 3 + (3 x 20) = 63 nm.

Excluding charts used in Polar navigation, the three types of maps commonly used for navigation, together with their primary characteristics, are listed here:

Lambert Conformal

• Most aeronautical charts are of this type.
• Lines of Longitude are nearly parallel.
• Lines of Latitude (meridians) are not parallel and converge at the poles.
• Great Circle is APPROXIMATED by a straight line.
• Rhumb line (a line that crosses all meridians at a constant angle) is plotted as a curved line.

• Many wall maps of the world are this type. Alaska and Africa are about the same size. I understand that it is used by mariners for navigation (not my area of expertise).
• Lines of Longitude are parallel.
• Lines of Latitude (meridians) are parallel.
• Great Circle is a curved line, except along Equator or True N & S on meridians.
• Rhumb line is a straight line.

• Weird. I saw one that was used to plot space craft trajectories. It's like looking at a globe through the end of a Coke bottle.
• Nothing is parallel.
• Great Circle is a straight line, which is its only reason for being.
• Rhumb line is a curved line.

Janet Whitney writes:

> TIGHAR chides me for thinking about a reasonable and
> uncomplicated plan for searching the sea floor for the Electra,
> while TIGHAR is spending years pursuing a theory that was
> unreasonable to begin with.

Some problems just aren't simple, and some answers aren't either.

The theory is indeed "unreasonable to begin with." But once you get beyond "begin with" and get into the basis for the theory, the facts that support it, it becomes very reasonable. It may not be correct, but it's reasonable. To get stuck at the "begin with" stage is to try to erroneously draw a simple answer from a complex situation.

I have to wonder if you've really read, and understood, the volumes of information available on the TIGHAR site and that have been exchanged in this group.

I originally came here after I heard about post-loss messages. That seemed so obviously simple. There either were, or were not, post loss messages. Well, it turns out that it's not that simple.

Try watching a few of those forensics shows that are so popular on cable right now. The ones where they track down the guilty party based on microscopic evidence, or get their clues from things like how far from the body the shoes were found and which way they were facing. I'm reminded of the Earhart search every time I see them assembling the facts for one of those cases. This is a lot like that. In fact, sometimes you'll see the very same techniques being used. They've solved some amazingly complex questions to which obvious, simple, wrong answers had been attached.

Bill #2229

At the very least, it shows that someone at the Department of State thought that the Japanese had warships in the Marshalls. This is the same intelligence that missed the Japanese planning to bomb Pearl Harbor. Their beliefs could have been incorrect.

Daniel Postellon TIGHAR # 2263

The communication alleges that Mr. Hayama (presumably of the Japanese Embassy) called Mr. Ballantine (presumably at the U.S. State Dept.) to tell him that the embassy had just received an offer from the Japanese government to help with the Earhart search because "Japan had radio stations and warships in the Marshall Islands...". This would seem to be a rather staightforward acknowledgement by Japan that it had warships in the Marshall Islands. What ships were they?

For his book Amelia Earhart : The Final Story, Vince Loomis went to considerable efforts to dig out the records of what Japanese ships were in the Marshalls in July 1937. He was trying to figure our what ship his star witness, Bilimon Amaron, had seen carrying the Earhart Electra on its aft deck. His book claims that he was able to determine that the Japanese really did not carry out the search for Earhart they later claimed to have made, because the ships of the "12th Squadron" supposedly used in the search were, in fact, in port in Japan the whole time. A survey ship also said to have participated in the search, the Kamui (meaning "God's power" and incorrectly listed as Kamoi in most Earhart books) was also in home waters. The only ship Loomis could come up with anywhere near the Marshalls was the seaplane tender Koshu. She was in Ponape, about 400 miles west of the Marshalls, on July 2, 1937 and arrived in Jaluit in the Marshalls on July 13. Loomis says Koshu then left Jaluit but returned sometime before July 19 when she sailed for Truk and eventually Saipan. It is between its departure from and return from Jaluit that he says the ship picked up Earhart, Noonan and the plane at Mili Atoll in the southern Marshalls.

LTM,
Ric

Ric wrote:

> It's the cloud shadows on the surface that could be a problem. They tend to
> look like islands.
>
> Does the SAR Manual assume that the ship is underway? A ship leaving a wake
> is much easier to spot than a stationary vessel. Itasca was hove to.

But cloud shadows don't look like white ships.

It's true that a ship leaving a wake is much easier to spot, because the intrinsic contrast of a wake is quite high. But wake detection dominates when the search aircraft is at high altitude, say more than 5,000 feet. As search altitude decreases, the apparent area of the wake decreases and the vertical aspect of the ship becomes more prominent in terms of the eye's ability to resolve targets in the vertical plane.

Although the SAR manual doesn't state assumptions about target speed, it looks like it assumes the target is dead in the water (DIW), which makes sense for a SAR situation. Setting up a search plan for a DIW target gives the highest probability of detection for a given sweep width.

Each sweep width table (sweep width being 2 X the detection range) includes not only ships of three different sizes, but also persons in the water, life rafts of various sizes, and recreational boats of various sizes. There is a table for each of several types of search platforms - - aircraft, helicopters, 90-foot cutters, and 41-foot cutters.

The detection range (1/2 sweep width) for an Itasca-size ship with an aircraft searching at 1,000 feet is 15 miles, given visibility of 25 miles. The detection range for the same target when the search platform is a 90-foot cutter is 13 miles. Since a cutter won't see a wake at 13 miles, it's safe to assume that the tables are based on a DIW target. Note also that the aircraft and the cutter are seeing the target at about the same range, which indicates that both are seeing it at grazing incidence, i.e., seeing its vertical dimension.

Ric wrote:

> Noonan's opportunities for "tight" navigation expired with the night. Once
> dawn cast its russet mantle adown the eastern sky he had only the rising sun
> and (maybe) the moon to use. The sun gave him a good LOP which he could then
> advance through Howland once he had his groundspeed sorted out. That should
> have given him a pretty good (10 miles?) idea of where Howland was in an
> east/west sense, but the north/south part of the equation depended entirely
> upon how carefully he had stayed on track during the night and how well he
> corrected for wind now that the sun was up. Of course, with a DF bearing to
> the destination it was no big deal if he was off a bit to the north or south.

Barring cloud interference, of course, that's pretty much what Noonan had to work with. He would have had the sun for east/west positioning and perhaps help from moon shots and two planets. The moon at 1950Z, just for example, could have provided about a 110 degree cut with the sun shot. The moon was up pretty high at around 68 degrees but it was a waning crescent moon with about 34% visibility. Venus might have been available at near the same altitude with nearly a 30 degree cut with the sun line. Finally Saturn was in the western sky but may not have been visible and would not have given a very good cut anyway. This information is courtesy of the U.S. Naval Observatory, Astronomical Applications Department.

Of course the bottom line of all this is that whatever information FN had did not lead him to Howland but may well have helped get him to Niku.

Also keep in mind we do not know for certain FN had the correct coordinates for Howland and if not what coordinates he had. He could have been working with about a five mile error on the assumption Howland was further east than it actually was. If that was the case he could have been right on and still missed both Howland and Baker.

Finally, looking at the Phoenix group and noticing they were mostly bunched to the east of Niku I wonder what reasoning selected Niku as the alternate as it would appear not to be simply by chance.

Alan
#2329

One thing we don't know -- and it's crucial for judging what opportunities Fred had for celestial sightings during the final run in after sunrise -- is when they began their descent from cruising altitude (presumed to be 10,000 feet) to the 1,000 foot altitude Earhart reported at 19:12 GMT. It seems reasonable that they would want to get down below the cloud base early enough to be sure that they didn't overfly Howland if they were a bit ahead of where they thought they were. It also seems reasonable that AE would plan her descent so as to get maximum advantage in speed and fuel economy. Altitude is an investment that is obtained at great expense. When you cash it in you want as much return as you can get.

As for selecting Niku as the alternate --- it's really misleading to think of it that way. Niku (Gardner), McKean, and Baker are the islands that just happen to fall along or near the advanced sunrise LOP Noonan knew he was going to be using. The other islands of the Phoenix Group were also out there further to the east but he didn't have a good way of finding them (any more than he had a way of finding the Gilberts if he backtracked). It may be that there was no time when AE and FN decided to "proceed to the alternate." Without help from DF and unsure of their position, they were doing the only thing they could do that stood the best chance of getting them to land of some kind --- running southeastward on the LOP.

LTM,
Ric

Ric wrote:

>For his book, Amelia Earhart : The Final Story, Vince Loomis went to
>considerable efforts to dig out the records of what Japanese ships were in
>the Marshalls in July 1937. [snip] A survey ship also said to have
>participated in the search, the Kamui (meaning "God's power" and
>incorrectly listed as Kamoi in most Earhart books) was also in home waters.

I'm looking at A. J. Watts' Japanese Warships of WW2, and there is no Kamui, but there are two different Kamois. One was the oiler Notoro, built in New York, converted to a seaplane tender in '32. The other was Kamoi Maru, an Army transport. No lisiting for Kamui; is there another spelling?

>The only ship Loomis could come up with anywhere near the Marshalls was the
>seaplane tender Koshu.

What is the Koshu? I see no listing for that spelling.

The 4th Mandate Fleet, headquartered in 1941 at Truk, included the Goshu Maru (launched in 1939) and Kamoi. Goshu Maru was converted, immediately prior to the war, to an aircraft transport.

>She was in Ponape, about 400 miles west of the
>Marshalls, on July 2, 1937 and arrived in Jaluit in the Marshalls on July 13.
>Loomis says Koshu then left Jaluit but returned sometime before July 19 when
>she sailed for Truk and eventually Saipan.

Has this been confirmed independently?

LTM (who can spell, but not in Japanese)
Mike Holt

Mike-san, the Kamui versus Kamoi thing comes directly from my old buddy Hiroshi Nakajima, Executive Director of the Pacific Society in Tokyo (a highly respected historical foundation). Nakajima dug out the original "Kohaku Nisshi" (Voyaging and Anchoring Diary) and faxed me the original kanji with his translation. My keyboard won't quite handle the kanji but the transliteration of the ship's name goes like this:

"Dai-Nippon Taikoku Gunkan (Tei) Kamui"

meaning "The Imperial Japanese Navy Warship (boat) Kamui."

He couldn't find anything on Koshu and Loomis's information has not been independently verified.

LTM,
Ric

Here's a pertinent extract from the book TFKing, and others are writing:

The U.S. also asked the Japanese to search the areas around the Marshall Islands, and official correspondence at the time indicated that they asked the oceanographic survey ship Koshu to do so. The Koshu arrived in the Marshall Island area on or about July 9th, and continued searching for about ten days. A 1949 U.S. Army Intelligence report states that despite the fact that no documentation exists in the Japanese Navy, interviews of Japanese officials on Jaliut and elsewhere indicated that both the Koshu and Kamoi searched the Marshall Islands, with the assistance of a large-type flying boat. Bridge logs of the Kamoi clearly state it was no where near the Marshalls during this time, and we have no documentary evidence that a flying boat was ever used to search for wreckage. The report also states that no traces of the Electra were found. ¹

The Japanese also offered to search the Gilberts, an offer that seems to have been (understandably) ignored. ²

The Koshu was doing oceanographic surveys, and based upon their reports, one can deduce from their speed and departure date to have arrived in the Marshalls (Jaluit) no earlier than July 9th. Official correspondence between the US Navy and State Dept. and Japanese officials at that time acknowledge only the Koshu in assisting in the survey for AE wreckage. I have the Kamoi bridge logs and transcribed them myself, and it was nowhere near the central Pacific.

Now, if only I could find those Akagi deck logs and when the planes were launched...(just kidding).

What's interesting about this Army Intelligence report is that it is the first document that names the Kamoi. Every AE book states the Kamoi and Koshu were involved in the search. Hmmm. Now about that seaplane...no confirming documents on its existance...but I wonder if the anecdotes about a plane being sighted in and around Jaluit during the search phase on the back of a ship was this seaplane and not AE's...I wonder...

1 US Army Intelligence, 1949a; Kamoi bridge logs in Jacobson archives; Maritime Safety Agency, Tokyo, 1951, Hydrographic Bulletin, 981(8).
2 Western Pacific High Commission, 1937a; U.S. Department of State, 1937; U.S. Navy, 1937e; Spading, 1997.

We clearly have the Kamui (Kamoi - whatever) nailed, but I'm a bit fuzzy about the Koshu. The Loomis book includes copies of various diplomatic exchanges between the U.S. and Japan but there's no reference to the Koshu. Mike Holt couldn't find a Koshu in A. J. Watts' Japanese Warships of WW2. I wonder what evidence we have that there even was such a boat?

Jane's Fighting Ships of World War Two lists Kamoi on page 202, classifying it as a "seaplane carrier" built by New York Ship- Building, and launched June 8, 1922 as a tanker, converted in 1932-33. Normal complement: 10 aircraft.

US Naval Intelligence reported it in Tokyo Bay July 2, 1937, sending out HF homing signals to its planes, as I've previously reported. (And you have already told everybody how completely unreliable my info is.)

Koshu (popular spelling) is not listed as Jane's, but is usually described as a "survey ship", and maybe didn't survive into WW2.

Cam Warren

I think we're all agreed that Kamoi was not a player in whatever the Japanese really did about searching for Earhart. We still need to find the Koshu.

The Honolulu Star Bulletin has an AP release dated 6 Jul 37 from New York; in sum, Japanese officials report that the " 2100 ton survey ship Kooshu [sic]" is searching in the Marshall Islands. In the main article the spelling is "Koshu", so probably an extra "o" typo. Also the Japanese were searching in "other areas near Howland".

This is probably independent corroboration of the Koshu's status. Fukiko Aoki, Japanese author, writes in Searching for Amelia Earhart in 1984 (not translated as of yet) that there were two Japanese ships in the area. The "battleship Koshu" and the carrier Kamoi. According to her, she reviewed the logs of the Koshu which reflect the dates and places reported by Ric. The Koshu left Jaluit on 19 Jul 37 headed to Saipan.

The Kamoi was docked in Saipan on 3 July, she says, but didn't get involved in the search but left 3 July steaming back to Tokyo.

Note: I should have the book translated within a week (informally) and shall report back.

LTM,
Ron Bright

The Star Bulletin article is only documentation of what Japanese officials said. Maybe it's true, maybe it's not.

I corresponded and spoke with Ms. Aioki while she was writing her book and was less than impressed with her research acumen. It's hard to understand how she could have seen the log of the Koshu and describe it as a "battleship."

I don't think we can be sure about anything about the Koshu until we get to some primary source.

A quick check of Conway's All the World's Fighting Ships 1922-1946 shows no Japanese warships by the name of "Koshu." The seaplane carrier section includes both Notari and Kamoi (both converted tankers, the latter built in Camden, NJ). I would presume that Loomis is mistaken.

Michael Lowrey

Curiouser and curiouser. Even if Koshu was a non-belligerent survey ship (as was the USS Bushnell), if she should still be on the IJN inventory. I'm beginning to wonder if we've uncovered yet another Earhart myth.

At the risk of sounding pedantic, "koshu" means "citizens" or "the public".

Re: KAMUI vs KAMOI

I suspect what we are experiencing here is a simple transliteration conflict. Technically, neither "Kamui" nor "Kamoi" is the correct written name for the ship in question, because its name would be written in Kanji (Chinese characters). How one wants to write that in "Romanji" (Roman writing) so that "gaijins" (foreigners) can read it, depends on what transliteration system you want to use. The most common system in use by foreigners is the Hepburn system. But it is not universal, especially if the transliteration is being done by Japanese. What it boils down to in this case is when a Japanese pronounces the name of the ship, do you hear a penultimate "u" sound or an "o" sound? This is further exacerbated by regional accents. The biggest stumbling blocks are phonemes that are not common to the respective native speakers. For English transliterations, the biggies are Rs & Ls and Fs & Hs, but there are also vowelular differences as well as syllabic accent differences that are much more subtle.

My point being, I wouldn't worry too much about Kamui vs Kamoi. It's the same name. If you had two different sets of Kanji with the same pronunciation [don't get me started on kanji "reads" --- we'll be here all night], then you would have two different names.

LTM (whose academic language was French),
Kerry Tiller

Arigato.

Marty Moleski writes:

> I suggest,
> with all due respect, that the hypothesis that "They
> missed Howland because Fred navigated the way he had
> in the past", though tenable, is not substantiated
> against other hypotheses.

I don't know why FN and AE didn't get to Howland but I do see a number of factors that may have affected their lack of success that may not have been properly attended to.

1. Although AE made a test hop to check out the DF it did not check out and apparently she decided it was because she was too close to Lae yet must not have checked it out again after the actual take off. It is possible it DID check out and then failed again. OR they elected to go without it.

2. It appears as though they elected to continue the flight without two way radio communication. They had to know that shortly after leaving Lae.

3. Given the small target Howland presented there should have been a number of ships spread out in the area to help. Even the two up at Nauru would have been a better aid joining the Itasca at Howland.

4. Upon departing the Howland area it might have helped if AE had broadcast their intentions on all her frequencies. In the running north south message she could have added what they would do if they didn't find Howland but then she gave virtually no info in any message.

5. If, if, if.

Alan
#2329

If there is a single glaring failure on Earhart's part that is difficult to explain away it is her failure to provide useful information in her several radio transmissions to Itasca. For someone who was more of a professional communicator (speaking and writing) than she was a professional aviator, Earhart was appallingly bad at giving the Itasca facts they could use to save her life.

A few days back I asked for TIGHAR's estimate of the potential error in attempting to fly the LOP to Niku, but did not receive an answer. What I'm after is TIGHAR's best cut at the effects of the following.

1. Uncertainty in the development of (taking, plotting, advancing, executing) the LOP.
2. Uncertainty introduced by flying back and forth along the LOP during the search for Howland.
3. Compass error (resolution and stability of the instrument and errors in estimates of variation or deviation on a given heading).
4. Pilot errors (how well could a heading be maintained – this can be a big one).
5. Accuracy in the ability to estimate and account for the crosstrack component of winds (also can be big).
6. Others issues (LOP being slightly east of Niku, etc)?

The cumulative effects can be at qualitatively estimated at best and worst case and the resulting figure (maybe an ellipse) and its diemensions estimated for that range of values. This gives some insight into how rational a decision it would be to "run down the LOP". This issue rises directly from Bob's Essential Conditions, and what I'm after is generally described by conditions 3 thru 5. Note that I'm not asking for a absolutely rigorous statistical analysis if that has not yet been done. Good, solid subjective estimates for the best and worst case would suffice.

TOM MM

The problem I have with that exercise is that, in the end, it seems like it would be fairly meaningless. The objective, as you state it, would be to determine how rational a decision it would be to run down the LOP. We already know that running down an advanced LOP was a "textbook" method for finding an island. (Weems' Air Navigation) I don't see any of the possible and quite legitimate variables you list that would not apply to any such attempt.

It may be worth restating what Weems said about the technique:

Finding A Destination.--During the daylight hours it is often impossible to get more than one LP [line of position], viz., that given by the sun. If pilotage cannot be used (as when flying over water) or radio bearings are not available, this single position line may be utilized for finding a destination.

The air navigator, having found a position line as he approaches his destination, continues flying on his course until the position line carried forward by D[ead] R[eckoning] passes through the destination. He then turns right or left and follows the LP. If, after a reasonable time, the destination is not sighted, he infers that he has turned the wrong way, and so reverses his track.

Found on www.ibiblio.org/pha/pha/misc/45-41.html

From: U.S. Congress Joint Committee on Pearl Harbor Attack Hearings; Pt. 35, the Clausen Investigation, pp. 52-62.

Fourth Fleet:
Survey and Patrol Division: Koshu

Seems to be some sort of cargo ship

Bingo. Nice work.

At least a ship by that name existed.

Ric wrote:

>If there is a single glaring failure on Earhart's part that is difficult to
>explain away it is her failure to provide useful information in her several
>radio transmissions to Itasca. For someone who was more of a professional
>communicator (speaking and writing) than she was a professional aviator,
>Earhart was appallingly bad at giving the Itasca facts they could use to save
>her life.

But, Ric, as you pointed out, the Itasca had a bad habit of not communicating with Earhart in the manner that she outlined and apparently in some cases was broadcasting when she was expected to broadcast. Therefore, much of the radio snafu seems to be on the part of the Itasca and who knows what AE was sending that didn't get through. She may have sent info and thought it was received but the Itasca was busy sending or on a different frequency and thus the message didn't get through. What Itasca heard may have only been followed up repeats by AE that were abbreviated from the first transmission. So, to say that AE was remiss in her transmissions may be erroneous as we can't account for Itasca's failing to follow the transmission timetable provided by AE, added to the difference in timezones used by both parties.

LTM,
Dave Bush
#2200

Itasca's errors, and there were plenty, were different in nature from Earhart's. The radio logs indicate only one occasion, at 19:45 GMT, when the ship may have "stepped on" a scheduled transmission by Earhart. It doesn't seem terribly likely that Earhart was doing a lot of transmitting "off schedule" but only getting through on her scheduled times.