Forum artHighlights From the Forum

October 29 through November 4, 2000
(page 1 of 3)

Contents:
(click on the number to go directly to that message)
1 Electra’s Vee Antenna Hue Miller
2 Erroneous Howland Position? Randy Jacobson
3 Kites as Antennas Hue Miller
4 Re: Kite Antennas Hue Miller
5 Compass Points Bob Brandenburg
6 No-Choice Belief Systems William Webster-Garman
7 Antenna and Propagation Bob Brandenburg
8 Fred Noonan Vern Klein
9 All Ashore That’s Going Ashore Steve Gardetto
10 SS Narwick? Ric Gillespie
11 Antenna and Propagation Hue Miller
12 Navigation Discussion Doug Brutlag
13 W40K Bob Brandenburg
14 Re: All Ashore Tom King
15 Re: Navigation Discussion Chris Kennedy
16 Re: Navigation Discussion Randy Jacobson
17 Re: Navigation Discussion Alan Caldwell

Message: 1
Subject: Re: The Electra’s Vee Antenna
Date: 10/30/00
From: Hue Miller

Janet Whitney writes:

> The installation and initial antenna tuning for ALL the aircraft
> transmitters described in Morgan’s 1930 book was tedious.

Tedious for whom, for Janet? It may be tedious to read about, I suppose, if you don’t find that interesting, but it’s a straightforward job. The technician actually did not need to read a manual, just look at it, it’s that apparent what needs to be done. ( I mean antenna peak-up, not install new channels.)

> The Collins "Autotune"
> transmitter’s final had to also be neutralized, by the way.

Hmmm....what’s the connection (so to speak)? Autotune was one answer to the multichannel demand. Neutralization is not performed every time the set is tuned to a new frequency.

> The WE transmitter and receiver experienced severe operating
> environments.

I would differ a little on this. Challenging environment. However, "I see no evidence" that temperatures were in the extreme high or low range, that voltages could climb dangerously high, and that outside of forced landings, the vibration level was more extreme than the designers had anticipated. The equipment, I believe, was protected from moisture and oil spray. Pardon, but I don’t see that its environment was that much more severe than any industrial communications, including taxicab radios, were exposed to.

>It would have been an excellent idea for Earhart’s radios to have
>been bench-tested in Darwin, vacuum tubes replaced, etc.

In the case of transmitter tubes, that might have been quite a spendy option. (Even back then, before W.E.Co. vacuum tubes became collectible.)

>However, it is unclear just how often and for how long the 13 C transmitter
>was turned on during the flight.

Probably only intermittently, yes? Altho the transmitter filaments, I suppose, were always on, as long as the transmitter was in standby. However, filament current, as I read, was somewhat limited (80% of full operation) in standby mode, and the series resistor limited inrush current, to ease the strain on the tube filaments from cold turn-on.

> The entire matter of the "harmonics" started being discussed after TIGHAR’s
> discussion was underway about "Betty’s" notebook. One thing that hasn’t been
> mentioned about the "harmonics" is the amount of concomitant audio
> distortion...which could have been significant...to the point where a 2nd
> harmonic audio would be mush.

Here’s another thing that hasn’t been mentioned about harmonics, data packed with quality: Around 1990 I was living in western Washington, in the greater Seattle area. I was listening one afternoon to the 2nd or 3rd harmonic of a Spokane radio station -- cannot remember which, except that it was in the upper part of the band, so that the harmonic fell in the region of low shortwaves. If you didn’t understand the language, you would have to believe the station intended to be there. There was no problem with audio whatsoever. Shortwave listeners, in fact, the hardcore ones, really like to log this kind of unusual signal. Altho in the last couple decades, it appears, the appearance of such harmonic signals has become pretty rare.

Last evening I was looking thru some 1930s radio magazines to #1 try to identify the station and frequency that appears in the Maine woman’s reception report, and #2 try to determine from reception reports, what bands were open, and how open, for the Pacific to Eastern US circuit, at the hours of reported receptions. In April 1937 Short Wave & Television, a USA listener reports hearing a Chinese broadcast station on 13.7 something, get this, the 2nd harmonic of their actual frequency, 6.8 something. No distortion reported, apparently pretty good reception. (Yes, a lotta "somethings" in this mention, but at a later date I’ll post the results of my investigation, with detail specifics).

Nor would the employment of screen modulation in the WE13 have anything to do with undue distortion on harmonics, once the transmitter was satisfactorily tuned up on the correct channel.

So, how about crunching them facts?

>So, Time to drop the "Betty" discussion. It has become entirely
>speculative. I would like to see a discussion of what TIGHAR hopes to find
>on Niku and how TIGHAR will go about looking.

Janet, what’s so sinful, in your belief system, about speculation? Speculations can elicit more facts. Facts can underpin viable theories. I’m sure the topics you mention will get further treatment.

-Hue Miller (chock full o’ data)


Message: 2
Subject: Erroneous Howland Position?
Date: 10/30/00
From: Randy Jacobson

Noonan’s 10 mile navigational uncertainty was based upon nighttime celestial navigation, shooting LOP’s from at least 2 or more targets. For the sunrise LOP, his precision of navigation would be that he could navigate the plane to within 10 miles of the LOP determination, but he would not be able to determine his position along the LOP at all.

As for the erroneous Howland position, Bill Miller, when he first worked the Line Islands (Howland, Baker, and Jarvis) colonization scheme in 1935/36, was the one who reported to the CG and US Navy the revised position. Richard Black, his successor, also knew of the revised positions. Bill Miller was AE’s technical liaison with the US Gov’t for planning the first flight. I find it absolutely inconceivable (but undocumented) that he did not provide her with the revised position. It was only "classified" until such time as the US Hydrographic Office could update their charts, which was done in 1938. It was not a true secret or classified piece of information in the strict sense of the word.


Message: 3
Subject: Re: Kites as Antennas
Date: 10/30/00
From: Hue Miller

Frank Westlake writes:

> When the time comes to improvise an antenna, she measures a piece
> of wire against the length of the vee antenna and attaches it to the
> feed-point. She launches her kite, attaches the other end of the wire to the
> string, then slowly pays out more string until the wire is taut.

Yes--- but does she use the total length of the 2 legs, or the length from the tap (junction on the antenna, to the far end of the other V ? That means, 2x one leg-length, or approx. 1.5 leg lengths.

Also, from my kite flying days (way long ago), I am thinking it would be a real hassle to keep up a kite with a relatively short string, like this, unless there was a pretty strong breeze....

Hue Miller


Message: 4
Subject: Re: Kite Antennas
Date: 10/30/00
From: Hue Miller

Mike Everette writes:

> This is total anecdote.......
> During my high school days I acquired an ancient WW2 Army handie-talkie
> radio......... Just for grins one day I tried touching the antenna to the
> school flagpole.
>
> WOW. The thing got out like Godzilla! I doubt the thing was very well
>matched to the flagpole/antenna... but the point is, the "antenna" made a
>huge difference.

I just deleted a paragraph of my own speculation on the reason. Suffiice it to say, I think maybe, and maybe as you do, the diminished antenna current with new antenna hooked on, due to some mismatch, is outweighed by the antenna current maximum now being higher in the sky, distributed over a longer length. This effect may even apply to the kite antenna, I’m thinking, if the new add on antenna was that advantageous over the old one.

Very interesting anecdote, Mike, thanks indeed for posting it. An interesting one to puzzle over. This is the kind of question that should appear on ham radio tests or CET tests ---no memorizing of multiple choice answer is possible.

Hue Miller


Message: 5
Subject: Re: Compass points
Date: 10/30/00
From: Bob Brandenburg

Ric writes:

> I know that sailors used to use a system of describing position or direction
> that employed phrases like "south by east" or "north by northwest" but I
> don’t understand it. I believe it dates from a time before the compass was
> divided into 360 degrees but was, instead, divided into "points" such as
> "north; north northeast; northeast; east northeast; east" etc. I’m sure
> some of our Old Salts can help us out here.

Ric is correct, as usual.

This old salt remembers that the compass card was divided into 32 "points" of 11.25 degrees each. These were, going clockwise, North, North by East, North Northeast, Northeast by North, Northeast, Northeast by East, East Northeast, East By North, East, and so on. Just to make it more fun, each point was subdivided into quarter points. For example, the subdivisions between North and North by East were North a quarter East, North a half East, and North three quarters East. A typical course order to the helmsman would be "Steer Nor’ Nor’East a half East".

By using the information above, it is possible to construct Table 2 of Bowditch. Details are left as an exercise for the reader. There will be a quiz later.

LTM, who says that the iron men in wooden ships were those who survived falling from the rigging.
Bob, #2286


Message: 6
Subject: Re: Caution – No Choice Belief Systems at Work
Date: 10/30/00
From: William Webster-Garman

Ric wrote, re definition of "cult":

>Now we just need to figure out where to build the compound.

I can see it now-- "NIKU IX... due to recent advances in desalinization and solar power generation technologies, the establishment of a permanent "research facility"... on a certain uninhabited island in the central Pacific is announced... symbolic of the bright future in store for this pristine jewel of the Pacific, approval has been secured to rename the main track that bisects the former colonial village on the island "Ric Gillespie Way"... work begins on "2 star" budget hostel for the rotating staff of researchers ...plans for new AE & FN Memorial Research & Administration Center with residence quarters for project leader..... [NOTE: benign joke --- ironic levity. ]


From Ric

Ironic levity aside, the possibility of an Environmental Research Center at Nikumaroro has been discussed. The world’s coral reefs are in big trouble and the one at Niku is still in very good shape as is the rest of the atoll’s relatively untouched environment. An archaeological study of the village and "Government Station" as the headquarters of the last expansion of the British Empire is certainly also justified. With cooperation from the Republic of Kiribati and a ton of money the place has real possibilities. All that, of course, is not TIGHAR’s knitting but if our work on the Earhart disappearance could act as a conduit for the island’s development for scientific purposes that would be a good thing --- but the Sir Harry Luke Highway stays the Sir Harry Luke Highway.


Message:

7

Subject: Re: Antenna and Propagation Simulation
Date: 10/30/00
From: Bob Brandenburg

Hue Miller wrote:

>> Since the wire antenna is on a metal aircraft, and is close to the
>> fuselage, the fuselage is the ground that the antenna sees, so the gain
>> pattern on the ground or in the air is essentially the same.
>
> --I was conflating into the term "gain" ideas about launch agle versus horizon.
> Probably I was talking about something I should have called something like
> "advantage". A 3/4 wave antenna did not seem to me to be so advantageous,
> compared with what are commonly called "gain antennas". I understand better
> now the question of gain in these calculations.

Just to be sure we are on the same page, when I use the term "gain", I’m referring to the antenna’s 3-dimensional gain pattern relative to that of an isotropic antenna (for non-radioites on the forum, an isotropic antenna is a theoretical point source antenna that radiates equally well in all directions), given the same power input to the antenna. The 3-D gain pattern includes, by definition, the effects of launch (or take off) angle and azimuth, as well as other effects such as current distribution along the antenna wires.

>> When that is proven, there is even a greater challenge, and that’s how
>> the Maine listener heard the AE messages on a frequency not related to AE’s
>> transmitter.
>>
>> That issue can be addressed using the same methodology as we are applying in
>> the case of Betty’s intercepts.
>
> Probably I am missing something here. It seems to me that this can be pretty
> much judged by math that even I can do.

Not everything comes down to mathematics. If it did, lawyers would be out of business (OK, I’m braced for the cries of outrage from our legal brethren on the forum ). By the "same methodology", I am referring to the overall comprehensive application of logic and rigor by TIGHAR when addressing the veracity of received information.

> --Alright. But forgive me for expecting that you have some
>dispassionate (maybe preliminary) inklings about the crediblity of certain
>reported intercepts.

Sorry to disappoint you, but I learned long ago that it’s wasteful of time and energy to indulge in prejudging what I want or hope the outcome to be when evaluating the credibility of reported signal intercepts. I let the facts tell me what the outcome is. Others on the forum are currently searching for the facts. If the Maine intercept, for example, is proven valid, then we have one more useful piece of the puzzle than we had before. If it is proven invalid, then we can put it aside and move on.

> BTW, regarding the question of the sensitivity/ pickup of the microphone
> in the aircraft cabin, which came up in a couple listener accounts, what
> would be the scientifiic method to resolve that? Do we have to reenact or
> simulate that scenario?

Simulation is not a silver bullet. It’s a last resort, useful only when it’s not possible to create a reasonable physical working model. For example, if we had an Electra 10-E and a WE-13 transmitter, we wouldn’t spend time with simulation, we would use the real thing to collect empirical evidence. As for the question of microphone pickup in the aircraft cabin, credible simulation would be virtually impossible - - too many undeniable variables such as the actual spectral composition of ambient noise in the cockpit, precise location of the microphone and the people who were speaking, etc. It’s far easier to reenact - - produces better, more reliable data, and the experiment can be conducted under rigorous controlled conditions, with multiple iterations to explore excursion cases.

>> .....Just trying to understand your reliance on the assumption that other
>> listeners must have been on the same frequency as Betty and therefore
>>should have heard the same signal.
>
> --Okay. Puzzling to me, that this reception occurred over hours, in the
>limited subset of the HF SW bands that were "open" during daylight hours,
>and not more widely reported or recorded.

The signal may have been more widely recorded and reported - - we just don’t know about any instances where that occurred. But the experience of Betty’s dad -- being dismissed by the local Coast Guard authorities - - might be typical of many other cases that we just don’t know about. But the fact remains that whether the signal was heard elsewhere is irrelevant to the question of the validity of Betty’s claim. Either her claim is true or it isn’t. The truth of her claim is not conditionally dependent on there having been other intercepts of the same signal.

> --I meant, "prime time" also considers what time frame is available to the
> listener. Not every listener can stay up all night listening for DX stations.
> I am thinking that in these hours, large numbers of students and day
> workers would have time to start tuning around.

But consider the constraints on membership in the probability space upon which your supposition rests. To mention just a few: of the students and and workers who would have the time, there is a subset who would be interested in listening to SW at all. Within that subset, there is a subset who have the means to listen. Within that subset, there is a subset of those who did listen to SW. Within that subset, there is a subset that listened to the right frequency. Within that subset there is a subset of those who were within an area where the signal was receivable. Within that subset, there was . . . . OK, you get the idea. It’s really not hard to believe that Betty is the only person to have heard the signal and to have written it down. But belief is not proof (with apologies to Marty ).

>> Neither am I aware of anyone trying to stretch the physics, or downplaying
>> "glaring problems", whatever that means.
>
> --Glaring problems means how a listener could (pretty reliably, per the
> Maine listener) report reception on an unfeasible frequency. What kind of
> light that might throw on similar reception elsewhere. How an aircraft
> carbon microphone can pick up conversations (even with the engines
> quieted). Call letters that are fictitious (WOJ) or don’t make sense (W4OK)
> in the context. Such are not just low speedbumps in the road to conclusions.
>
> Okay, how do we deal with those in the scientific process?

At the risk of oversimplifying, I suggest that each of those questions can be stated as a testable hypothesis. The test tools and procedures are chosen to suit each case, and the scientific method is applied using three principal ingredients - - rigor, rigor, and rigor.

LTM,
Bob #2286


Message: 8
Subject: Fred Noonan Mentioned
Date: 10/30/00
From: Vern Klein

Looking through Aero Digest for the year 1936 for whatever might be of interest I spotted only one article that may be of some interest. In the January 1936 issue there is an article by Lt. Comm. P. V .H. Weems, U.S.N. (Ret), on the "Accuracy of Bubble Sextant Observations." Whether it was an octant or a sextant, he spoke of it as a sextant. He made a total of 110 observations (sun altitude) from an open cockpit plane while flying from Maxwell Field to Langley Field.

His conclusion: "This series of tests, supported by thousands of other similar observations, proves that bubble sextant errors can be reduced to an extremely low figure when sufficient observations are averaged. Indications are that it is inadvisable to throw away wild shots because the observer cannot always tell which shots are wild, and the law of averages may be depended upon to reduce errors to practicable limits, say below 5 miles, when sufficient sights are taken and averaged."

In the last paragraph, he wrote: "The importance of celestial navigation for position finding is indicated by the fact that 90% of the first Pan American Airways’ trans-Pacific flight was made over clouds which made direct drift observations impossible. Celestial navigation was used by Navigator Fred J. Noonan, with such surprisingly accurate results, that the ‘China Clipper’ reached Honolulu within a short time of its scheduled arrival."


Message: 9
Subject: All Ashore That’s Going Ashore!
Date: 10/30/00
From: Steve Gardetto

The Forum for the last few months has been captivating, although I confess that the radio physics dialog leaves me with the MEGO (my eyes glaze over) syndrome, and the thing about pirates, well, never mind.

I’d like to jump back to something that came up a few months ago, namely, the work plan for next expedition. IIRC, you’ve mentioned that at the beginning and end of each day, there’s about a 1-hour process of getting the expedition members to and from Niku and Nai’a.

Here I go assuming things, but I "ass-u-me" that this must be done with sufficient ambient light for navigation; in other words, you’re not waiting until sundown before heading back from Niku in the "commute boat" to Nai’a. Thus, the "daily commute" at the start and end of each day appears to reduce the available working time for the expedition by a total of about two hours.

There are many reasons for everyone being aboard ship overnight, such as group cohesiveness, fresh water and food, bathing, reviewing that day’s results and planning the following day’s activities, plus preparing any special equipment (diving, photographic) that may be needed.

I’ve not been on a single TIGHAR expedition and you’ve safely led many teams across the Pacific and back (which is just a few words to type, but is in reality a stupendous accomplishment), so I freely admit I’m naively submitting this question, but I don’t think it’ll be the most ridiculous thing that’s been posted.

I was wondering about the possibility of leaving a small group, say four people, ashore on Niku for alternating nights, while the rest of the expedition returns to the ship. Upon arrival at Niku, the expedition could transport ashore a few pup tents, sleeping bags and foam pads, chow, lanterns, water jugs and other supplies. After the initial transport, only water and food for 4 people would need to be replenished each day. (I saw your recent comment about the impracticality of transporting ashore a 200-lb tide-tracking buoy, but I don’t think that the overnight supplies for four people would be nearly as cumbersome).

After staying ashore one night, this group of four would then return to the ship at the end of the following day, to be replaced by another group of four. The key point is not that they would be ashore to search at night, but that they could continue working during the last hour or so of light at the end of the day and the equivalent period in the following morning, before the "commute vessel" returns with the remaining expedition members.

The shore party might do things like completing site surveys, sifting sand through filters at specific locations, preparing for the next day’s events, etc. I don’t think you’d want anyone cutting scaevola by swinging sharp steel instruments in reduced lighting (I wonder how much cooler these times of the day are). Perhaps at some site there could be some work done by the light of a few lanterns.

In any event, if four people are able to safely put in an extra hour of work in the evening and in the following morning, you’d be able to get approx. an additional person’s worth of labor done (although this does call to mind the saying that nine women working together can’t produce a baby in one month!). By rotating the "overnight crew" there shouldn’t be too much additional strain on the team.

So, boiled down, my questions are:

Is there work that can productively and safely be done by a small onshore group in the available light between the time when the "commute boat" normally departs and sundown/sun-up?

What are the typical "aboard-ship" activities at the beginning/end of a workday during an expedition, and what is the timeline ashore for a typical day on Niku?

Is there any existing shelter ashore? (I seem to remember postings that there were some buildings still standing from the PISS settlement, but that they’re now overgrown and unreachable?)

How does the "commuting" process actually work (does everyone fit in one trip or are two trips required; is there some sort of dock or does everyone wade ashore like at Normandy; what are the typical sea/surf conditions)?

Finally (and I know this has been a long post, but if the radio guys can do it...), in keeping up TIGHAR’s incredible safety record, what are the things you tell the expedition members to be careful of and what have been the close calls?

I joined the forum only about the time of the last expedition, so all this may have come up before, in which case, just aim me at the appropriate archives. I suspect I’ll hear this idea may be a case of the risks not justifying the rewards, but nothing ventured...

LTM (who always tries to put in a full day’s work)

Steve G., TIGHAR # something or other


From Ric

Steve, I think you have an interesting suggestion here and I’d like to hear some opinions from team members.

To answer your questions:

Typical "aboard ship" activities include writing up the day’s field notes, cleaning or repairing equipment, planning for the next day’s operations.

There is no existing shelter ashore that would be usable but there is also little need for shelter beyond a simple tarp.

It usually takes at least two trips to get everyone ashore.

There is no dock. The launch must transit a roughly 500 feet long by 30 feet wide channel blasted through the reef to get to the beach. At high tide the reef is submerged and it’s just a matter of staying where the water is bluest. You can drive right up to within a few feet of the beach. You still go ashore Normandy-style but with considerably less automatic weapons fire. If there’s a big swell running it’s a bit hairier and going in through (or rather over) the channel is a surfing experience. Getting out of or into the launch at the beach end can also be interesting.

At low tide the situation is a bit different. The water level can be a foot or so below the level of the reef so going through the channel means having sharp, jagged walls on either side. The launch can’t get nearly as close to the beach so we use the reef as a wharf and disembark or embark directly onto the reef flat. In really calm conditions it’s a piece of cake except that the reef is quite slippery. However, when there’s a swell running the channel becomes a chute and the waves come rolling in with a vengeance. The launch heaves up and down as the water level in the channel fluctuates with each wave and clambering out of or into the launch onto the reef flat safely requires timing and nimbleness and steady nerves.

When the weather is really bad and the swells are several meters high -- as they were when we were there in March of ’97-- well, let’s just say that we’re not going to do that again.

Lessons from close calls:

  1. If an outboard motor quits when you’re trying to deal with surf, life can get real interesting. In surf conditions an unreliable outboard is a no go item.
  2. A diver underwater can keep an eye on the sharks with no problem and they’ll usually keep their distance, but a swimmer (or diver out of air) on the surface looks like lunch.
  3. Don’t wade in the lagoon if you’re bleeding. (duh)
  4. Don’t jump out of a launch into shallows in the lagoon without keeping a firm hold on the boat. What looks like a firm sandy bottom might be quicksand.
  5. Don’t wade in the shallows alone (for the same reason).
  6. When walking through scaevola -- even areas that have been "cleared" -- it’s easy to trip. If you’re lucky enough to miss the sharpened stakes left by the machete work, the coral rubble will do a number on your knees and your face.
  7. Don’t pet the bunnies and squirrels. If a coconut crab gets hold of you, you’ll wish he hadn’t.

LTM,
Ric


Message: 10
Subject: SS Narwick?
Date: 10/30/00
From: Ric Gillespie

Yesterday we received in the mail a copy of a memoir published by TIGHAR member and forum subscriber Capt. John W. Clark describing his long career in the merchant marine. In it he makes several passing references to the disappearance of Amelia Earhart. After looking through the book I sent him the following email:

Capt. Clark,

Thanks for sending us a copy of SSS. I look forward to reading it.

In checking the references you made to Earhart I note that on page 496 you say that the sailing directions for Gardner Island mention the wreck of SS Narwick. The time seems to have been December 1945. Of course, the name of the ship wrecked at Gardner is actually SS Norwich City but the apparent error in the sailing directions is very interesting. If, as early as 1937, the ship was reported to be the Narwick, that could explain Earhart’s repeated (alleged) transmission of "New York or something that sounded like New York" as described in Betty’s notebook.

Do you, by any chance, still have the sailing directions that were in use in 1945? The earliest sailing directions (H.O. Pub. No. 166) I have are from 1952 and they have the correct name of the ship. I also have the report submitted to the Hydrographic Office by the USS Bushnell survey in 1939 which also has the ship name (but not the grounding date) listed correctly. So where, I wonder, did SS Narwick come from?

Ric

Capt. Clark was kind enough to send the following reply:
Ric: During my South Pacific days I often abbreviated many islands, etc. in my notes/logs. Perhaps I inadvertently misspelled NARVICK, and referred to same in my book based on my notes and a more than 50 year old memory. I don’t have a copy of the 1945 sailing directions but you should be able to obtain copy from the U. S. Hydrographic office. Incidentally, the current sailing directions only refer to a "conspicuous stranded wreck".

Regards,
J. W. Clark


Message: 11
Subject: Re: Antenna and propagation simulations
Date: 10/30/00
From: Hue Miller

Bob Brandenburg writes:

> What is the relevance of the harmonic radiation properties of military
> transmitters to the harmonic radiation properties of AE’s transmitter?

The reason I looked for data on these, is for that period, simple output circuits were used, with less concern for harmonic output levels than in the postwar period. Unfortunately, I found less hard data than I hoped for - harmonics being a concern only when actual trouble, as in interference, was caused.

> Assuming that the figures given to you are factual, do they include any
> implicit caveats, such as transmitters carefully tuned and feeding appropriately
> matched and loaded antennas?

Yes. (and "of course", I’d say.) The above question really has two parts: tuning and matching. I think we can hazard an assumption that the WE13 transmitter carried on AE’s plane was correctly tuned up. It did work, after all. Tuning will have to be fairly close, or output will fall off very rapidly. Too far off resonance, and the tubes are damaged, or the power fails due to overload.

What I want to say on this point is: mistuning the transmitter would do far more to diminish power on the actual transmitter channels, 3105 & 6210, and would be quickly noticed, than it would do to boost harmonic radiation. For example, mistuning of the transmitter output tuning, say to resonate at 6.6 MHz, would much more seriously affect the output at 6210 than it would do to some frequency 6 or 12 MHz away. Nor could one say, maybe it was radically mistuned, tuned to a harmonic, because then the output on the fundamental would be nil. In fact, I would say, given the safe assumption that the transmitter was not tuned to a harmonic, that harmonic output would be maximized by having the transmitter correctly tuned. Most harmonic power is not developed by the amplifier amplifying discrete harmonics, but by its developing a powerful, complex waveform. Or not?

As for loading adjustment, it seems to me that having the antenna takeoff higher on the tuned circuit favors harmonics. That setting on the tuned circuit is the one for non-resonant antennas, i.e. the 3105 channel.

If the WE13 transmitter was mistuned:

1. output on 3105 or 6210 would be down
2. voice quality might suffer, sound distorted
3. to some much lesser degree, harmonic output might be somewhat higher -- but I say, not enough to rule the harmonic-broadcast theory in or out.

Of course, regardless of which particular harmonic was stronger at the transmitter, the one which was critical for any long distance reach would be the one favored by whatever antenna was in use, and the propagation on the path to the listener.

Harmonic output from AE’s radio transmitter shouldn’t be attributed to some technician’s mistake or some maladjustment. It was a function of this circuit acting normally, within its design limitations.


From Ric

> If the WE13 transmitter was mistuned:
>
> 1. output on 3105 or 6210 would be down
> 2. voice quality might suffer, sound distorted
> 3. to some much lesser degree, harmonic output *might* be somewhat
> higher -- but I say, not enough to rule the harmonic-broadcast theory
> in or out.

1. "Down" compared to what? We know that the communications check on July 1st was considered to be successful but we also know that the airplane remained very close to the station. We have some indication of how well Earhart’s transmitter was performing on July 2nd 3105 and 6210 based upon the reported receptions by Lae andItasca. I don’t see that we have anything to measure against to know if the performance was "down" or not.

2. You say the one indication of a mistuned transmitter would be that "voice quality might suffer, sound distorted." Chater reports that the Lae wireless operator who inspected Earhart’s transmitter found that

TRANSMITTER CARRIER WAVE ON 6210 KC WAS VERY ROUGH AND I ADVISED MISS EARHART TO PITCH HER VOICE HIGHER TO OVERCOME DISTORTION CAUSED BY ROUGH CARRIER WAVE, OTHERWISE TRANSMITTER SEEMED TO BE WORKING SATISFACTORILY.

What, other than mistuning, might cause the distortion reported?

Message: 12
Subject: Navigation discussion
Date: 10/30/00
From: Doug Brutlag

I read with great interest the postings on FN’s navigation abilities, chart inaccuracies, offsets, LOPs, etc.

I agree that FN’s usual & average accuracy was about 10 miles and he alludes this in a letter to navigation guru of the time Mr. PVH Weems. I’ve personally done enough shots with hand held sextants of WWII vintage including a Pioneer A-7(similar to FN’s A-5) and have proved this to be true to myself. It’s also true you can do better than 10 miles if you have a lot of experience using a sextant and steady eyes & hands although when I was that fortunate I credit it to more luck than skill, but nevertheless it can be done.

Fred Noonan was an ace navigator. Drinking on the job? B.S.! It cannot be done folks, no frigging way.

While trying to work up some plotting charts for the Howland leg I have been frustrated in researching what documents I can find, an almost total lack of position reports from which to go on. I can only find one and it indicates they were south of the great circle course at the time. Anybody have anything in that regard I could borrow?

Direct or offset course I cannot determine right now. I am certain of one thing though. I just got back from flying a trip across the pond to Italy & back, re-provisioned myself with clean clothes and then went to the Caribbean & back. Thank God I have the next couple of days off duty free as I am wiped to say the least.

Ric: I have to believe that if any miscalculations were made or perhaps tie into this, fatigue played a part in this tragic mystery. Besides pushing the airplane to the limit, they also pushed human limits to the envelope & perhaps beyond with a fast paced & hectic flying schedule, time zone changes, inadequate rest periods for fatigue & body clock adjustments.

In addition to fatigue, I highly suspect Fred was having trouble getting enough visibility during the night to take star shots, being as they were in the inter-tropical convergence zone with its propensity for garbage weather conditions. Inability to get a timely position update would effect the accuracy of DR calculations, although if Fred got at least one good fix per hour that would be sufficient. In fact, one would not want to take too many fixes too close together. Why? If fixes are not sufficiently spread apart a navigator would not be able to determine winds aloft & drift with any real accuracy. Am I correct Alan? One has to not only has to see course deviation occur, but also the rate/ mileage of deviation over a given time period to determine winds & drift. One would otherwise end up trying to go from fix to fix(left-right-left-right, etc.) using guesstimates more than calculations, due to lack of enough raw data. In other words, an error has to be made and judged (calculated from observations & plotting) before one can make a reliable correction.

When you are attempting to fly a great circle course over a long distance as this, the navigator will divide up the course into a series of rhumb lines, say a couple hundred miles apart or so, or so many degrees of longitude apart as they were heading almost straight west to east. In any case, he would try to plan his routing & waypoints with planned shot times to calculate a fixes at strategic or convenient points along the way. If it were my trip, I’d use points of longitude at intervals that would get me one good fix an hour(assuming I can get my shots). In between, I’d monitor the progress and look to see which way we were drifting, note the bearing & rate of drift and calculate a wind at my altitude & make a correction, logging all data on the plotting charts & sight reduction form.

Situational awareness is a watchword pontificated by professional aviators. In this case, it was vital. Any lack thereof could & would be deadly. I gotta believe fatigue had some negative effect in this aspect. Sound familiar Alan?

Awaiting comment from the celestial choir.
Doug Brutlag #2335


From Ric

The wait-and-see-what-the-error-is-and-then-make-a-correction method is exactly what Noonan seems to have done on other flights. Right Randy?


Message: 13
Subject: W40K
Date: 10/30/00
From: Bob Brandenburg

The great circle bearings from St. Petersburg to Niku (266.8 degrees true) and Lake Worth (W4OK) to Niku (267.8) put all 3 very nearly on the same great circle. I’ve spot checked a few other sites (Ascension Island, Los Angeles, San Diego, Honolulu, etc) to see if they might also be on the same GC, but none are.

It also is interesting to note that the GC bearing from Lake Worth to Howland Island is 273.7, and the GC bearing from St. Petersburg to Howland is 272.6.

Do these facts, when combined with the "W4OK Howland Port" entry in Betty’s notebook mean she heard W4OK working the hams on Howland, or perhaps that she heard W4OK trying to reply to AE’s signals? Or is it all just coincidence? Dunno, but others may have some views on this.

LTM, who doesn’t believe in coincidences.
Bob Brandenburg #2286


From Ric

I think we really need to ask Harry Poole to check the Lake Worth paper for that week to see if perhaps a Mr. F.G. Carrol of 711 Ninth Avenue may have reported hearing anything from Amelia Earhart. Wouldn’t it be interesting if Mr. Carrol’s nickname was "Bud."


Message: 14
Subject: Re: All Ashore That’s Going Ashore
Date: 10/30/00
From: Tom King

It won’t surprise you, Ric, to learn that I think Steve’s idea is excellent. The two nights that John Clauss, Lonnie Schorer, Gary Quigg and I spent ashore in ’97 made for some very productive days, and that with very little preparation (it wasn’t exactly a planned event). It also enabled us to save the very expensive GPS base station from unexpectedly high seas -- something to consider if we need to put major equipment ashore in the future. Plus, you just get a whole different sense of the island if you’re there full-time, including nights; that has practical advantages in terms of better appreciating the dynamics of the place and what they can do to physical remains, and intangible advantages as well, though I have trouble characterizing them. As for any dangers, I don’t think they’re any greater than those incurred by getting in and out of boats at either end of the "commute."

LTM (who’d very much like to be ashore on Niku)
TKing


Message: 15
Subject:

Re: Navigation discussion

Date: 10/30/00
From: Chris Kennedy

There’s been a tendency on the Forum from time to time to characterize the round the world flight as a publicity stunt with no real aviation value, and that all the pre-flight buzz about the dangers of the Lae--Howland leg as hype to build up the suspense to a level higher than really warranted. I wonder if this is really fair, however. The reason I say this is because of all the debate and disagreement on the Forum concerning such "basic" things as how you determine and interpret LOP, how and when you take celestial shots, judge wind speed and direction, etc. etc. Notice that none of this has anything to do with radios or electronic direction finders. Yet, here we are in the year 2000, 63 years after the fact, yet all you technical experts out there are still debating and disagreeing on so many things which one would think to be so basic and "settled". It turns out they aren’t so settled now, and were therefore certainly not settled then. The real tragedy of the flight is that so much of the communication equipment aboard the Electra and the Itasca that was supposed to supplement these "basics" was, for whatever reason, unable to communicate as intended, and that for all his celestial observation skills in the "basics", the "basics" weren’t enough and Noonan was unable to bring the flight home before whatever happened occurred. Therefore, it seems to me that had Earhart and Noonan managed to actually get the Electra to a pinpoint landing on miniscule Howland after flying so long over water, that, in and of itself, would have been a considerable accomplishment, and takes the flight out of the category of a mere stunt.

--Chris Kennedy


From Ric

Pan Am had been flying scheduled passenger service across the Northern Pacific for nearly a year before Earhart and Noonan disappeared. They were regularly and reliably hitting tiny islands (Midway and Wake) using exactly the same technology AE and FN were using (celestial and DR to get them close and DF for the final run in). What made Earhart’s flight unusual was that she was using a relatively small land plane instead of a large flying boat. The pioneering work in transpacific aviation had been two years before -- largely by her own navigator. Earhart’s flight was using proven methods and had no practical application for commercial air travel. It was a stunt.


Message: 16
Subject:

Re: Navigation discussion

Date: 10/30/00
From: Randy Jacobson

FN was my kind of navigator: he would monitor the flight with celestial navigation, perhaps once an hour or once every two hours. He would only offer up course corrections when deviations from planned course were sufficiently large, on the order of 50 miles or so, so that a decent enough course change could be made. Changing a course from 076 to 077 degrees really doesn’t buy you much precision, but changing from 076 to 081 might. He seemed to plot out future positions based upon past celestial navigational fixes for at least 3 hours into the future (dead reckon) at half hour intervals. By taking another celestial fix at opportune times (between bottles or naps ), he has a ready basis for determining how far off course he is. If reasonably tolerable, he lets it go; otherwise advise the pilot to change directions.

It is pretty simple, and keeps the navigator from micromanaging the pilot.


Message: 17
Subject:

Re: Navigation Discussion

Date: 10/30/00
From: Alan Caldwell

Doug Brutlag writes:

> If
> fixes are not sufficiently spread apart a navigator would not be able to
> determine winds aloft & drift with any real accuracy. Am I correct
> Alan?

Doug, you are exactly right. Frequent fixes would jack you all over the place. We typically did one per hour just as you described.

This was not in YOUR post, Doug but I want to comment how difficult it is to lay to rest certain statements that are either dead wrong or have no factual basis to support them. The navigation issues have been discussed and re-discussed for a long time and misstatements continue to crop up. For example, long ago someone theorized about the use of a sunrise LOP. That is, without a doubt, the most useless and inaccurate procedure in all of celestial navigation -- for a number of reasons but the most obvious is the atmospheric distortion at sunrise makes the resulting shot unusable. Why this keeps coming up is beyond me.

Another issue is that weather prevented or interfered with Noonan’s night celestial. Maybe it did but who knows and if so to what degree and was the interference significant. Every navigator has shot through thin overcast at times. Someone show me the documentation that proves Noonan could not get a celestial shot at any given time that he planned on.

The sun provided Noonan with an LOP across his inbound course. IT DID NOT GIVE HIM LATITUDE. Assuming he turned SE toward the Phoenix Islands sun shots helped him stay on course but still did NOT give him latitude.

Why are people so determined Noonan had nothing but the sun to shoot during daylight hours? I’ve even seen statements that conceded there might be other bodies to shoot but they were behind the plane too far to be shot. Is there anyone in the forum who is not aware the Electra was capable of being turned? Just push on a rudder, bank gently, roll out and Voila! Celestial objects that were not in sight now are. Amazing.

Frustrating.

Alan, #2329

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