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Amelia Earhart Search Forum => General discussion => Topic started by: Ric Gillespie on February 12, 2013, 08:13:19 PM

Title: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 12, 2013, 08:13:19 PM
But this whole plane superstucture hanging around just underwater, in perhaps 10-20 feet of water, visible at certain times and tides is far fetched to me and doesn't fit with the near vertical drop off once past the breakers that has been described by visitors.

I don't know what visitors you've been listening to but there is definitely an area of shallow water sloping down to depths of 60 feet or so before the first cliff drops off. 
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 13, 2013, 07:44:58 AM
But this whole plane superstucture hanging around just underwater, in perhaps 10-20 feet of water, visible at certain times and tides is far fetched to me and doesn't fit with the near vertical drop off once past the breakers that has been described by visitors.

I don't know what visitors you've been listening to but there is definitely an area of shallow water sloping down to depths of 60 feet or so before the first cliff drops off.

I have been listening to you.
 I have never visited, so I like 99% of others rely on Tighar for the description of everything to do with the island. Unfortunately in visualizing and also in descriptions the areas sometimes change drastically depending on which small section is being mapped and how the charts are drawn. The Wiki description honestly is confusing as it goes back and forth describing windward and leeward sides, when windward and leeward can change. Is Windward around the Norwich or is that considered leeward? At one point the Wiki reference seems to include the Norwich side as the leeward side. When in other references it states from March to November is the "westerlies", so the Norwich side would be the windward side. It might be easier to describe it by landmarks or compass points.

The  general description I have gathered is the south(leeward side) has a shelf (or shelves) and a spur and groove section on the site seven section, variously called the Northeast, but also the southeast side. The one common description from Tighar is that the area around the Norwich was drastically steeper and contained few ledges to hold a wrecked craft. Yes there is water from one foot to 1000 feet, but is the area around the Bevington photo shallow enough AND with a low enough slope to hold wreckage and also to play peek a boo depending on the time of day and weather?

From the Wiki reference-
"Beyond the reef edge is the steep drop-off zone. The average gradient of the upper submarine slope down into the abyss is about 40º"


This indicates a very steep slope which would have a hard time holding a relatively light aircraft. If the wreckage is assumed to be in 20 feet of water(is that the current theory?), then what is the slope there? If it's in 50 feet of water what is the slope there? Are there wide enough ledges with low enough slope to withstand tidal action and storms in that particular section of reef. The Wiki reference material doesn't seem to indicate that at all.

Like a lot of folks just trying to grasp the simple verbal description of what side a lambrecht photo was taken, there seems to be much confusion(by myself first in line), as to what this dynamic reef looks like underwater, and I suspect a lot has to do with where on the atoll the measurement is taken. You go 50 meters around the circumference and it seems to change.

The one thing that does seem clear is there is a much steeper slope, sometimes referred to "almost vertical" by yourself, on the Norwich side along with reef undercutting. We have descriptions of ships not being able to anchor around the Norwich because of the depth and slope and having to tie off to the Norwich.
Why couldn't they anchor if there is a 60 foot deep wide stable flat that can hold an airplane? In my opinion, No Anchorage means there are no flats like you now describe in the Bevington area.

This doesn't sound like a wide, low slope 30-60 deep flat in that particular 200 meter wide area around the Norwich. At least not with a slope in 20ft-50ft range where a plane could hide out and re-appear. Obviously if it's too shallow a relatively larger aircraft will be visible, and if too deep it will never appear to the islanders. Like the 3 little bears, this peek a boo theory has to be just right, with just the right slope and just the right depth, and relatively protected from violent storms.
I just don't see a plane hanging up in a 3 little bear area, not near the Norwich. It seems too dynamic, steep, and violent.

I will say while the color sonar maps are great, if they were marked in depth and slope it would give a much better understanding to non visitors and casual readers trying to grasp the full scope of the island.
 I wish there were better marked maps and graphs, Graphs like the following are hard to interpret and very simplistic, which makes much ambiguity whether talking about tidal datums or areas plane wreckage could be hidden.
http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/TidalStudy/reefflat.html

So from the graphs and descriptions provided, a  high slope, steep dropoff, no anchorage, it would seem the wreckage would have to be in the perfect spot, on the perfect little ledge, just sitting there for years for Emily to spot it, and that to me seems unlikely.
I think it went deep and went deep fast if the wash off the reef theory happened anywhere on the Norwich side of the Island.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Greg Daspit on February 13, 2013, 09:18:38 AM
 Attached is a pdf of my understanding of the reef and underwater debris field from descriptions, and photos. I have added my own speculations just to test and study. I modify it as I learn more so it is just my interpretation to date and may be wrong or incomplete. Also attached is a reef survey Ric previously posted. My pdf, like many graphics is only a general diagram/ sketch. It's not a surveyor's profile drawing with the benifet of alot of elevations shot.
I inserted a picture of a strut to show it gets rust colored and the kite photo to show what looks like crevices and holes nearby the estimated Bevinton Object location.
(edit pdf to show 197' dim. instead of 97')
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 13, 2013, 09:18:54 AM
Let me see if I can clear up some confusion.  The long axis of the atoll runs roughly NW to SE. The long shoreline that runs from the NW tip, past the Seven Site, to the SE tip where the Loran station was is referred to as the "windward side" because the prevailing wind in from the East.  All other shorelines are on the "leeward side" of the island.  Severe weather almost always comes out of the west and northwest ("westerlies").  On those occasions the west side of the island where the shipwreck is takes the brunt of the wind and waves.

Along that western shoreline from Norwich City northward to the Bevington Object location our knowledge of the reef profile is derived from
1. observations on the surface at low tide
2. photos and video taken by scuba divers at depths from the surface down to about 100 feet.
3. ROV video, multi-beam and side-scan sonar images at depths greater than about 200 feet. 

We know from scuba divers and ROV video that just offshore the spur & groove zone the reef drops off to a level or mildly-sloping shelf that varies in depth from roughly 20 to 40 feet, then the slope steepens down to a depth of about 80 to 100 feet at which point it drops almost vertically about 200 feet.  The attached photo was taken at a depth of abut 60 feet.  This region from the reef edge out to the first cliff was too shallow to be mapped by KOK's ship-mounted multi-beam sonar and too hazardous to be mapped by the AUV's side-scan sonar.

The attached map of ROV Dive 13 shows the "snail trail" of the ROV as we searched the mildly sloping shelf at the base of the first cliff.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 13, 2013, 09:52:09 AM
The attached map of ROV Dive 13 shows the "snail trail" of the ROV as we searched the mildly sloping shelf at the base of the first cliff.

Ric, I don't see an "attached map of ROV Dive 13". Am I missing something?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 13, 2013, 09:58:52 AM
Ric, I don't see an "attached map of ROV Dive 13". Am I missing something?

Oooops!  Sorry.

Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 13, 2013, 11:25:31 AM
Ric, I don't see an "attached map of ROV Dive 13". Am I missing something?

Oooops!  Sorry.

That looks great. Thanks.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 13, 2013, 12:57:39 PM
Thank you Ric, that is most helpful. If I may, a followup just to make sure I am on the same page.
So on the snail trail graph, the area marked in Black that says "first cliff not mapped", that black area on the snail trail map is 20-40 deep and it does not include the spur zone? It is seperated from the spur zone?

If I am understanding correctly the spur zone does go dry periodically(or not?) and that spur zone is the area where in theory the bevington object was at? That would be in 3 feet of water at high tide?

Then offshore of the spur zone is the blackened area not scanned that has a mild slope and is 20-40 feet deep?
So what is being called the "first cliff" is the dropoff from the spur zone into the mildly sloping 20-40 waters where it is theorized
a wreck may have hung around for some time. Eventually dropping down successive cliffs.
Is that the correct picture?
How wide(from spurs to second cliff) is this blackened area not mapped that is relatively shallow? Did suba divers cover the whole area?
(it would really help if you could just fly everyone out to look for themselves! Haha)
Also thank you Mr.Daspit for your PDF as well.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 13, 2013, 01:24:40 PM
Jeff, I think Ric was describing the spur zone as different from the "not mapped" blackened area on his graph.
I think it goes like this from Rics latest description-

Reef flat 200 meters wide from beach to end of spur zone
Then spur zone(not sure how wide this entails)
1st cliff off the real shallow spur zone into 20-40 feet of moderate slope coral.(again not sure how wide this non mapped area is)
Then another dropdown to 100 feet of water where slope increases to "moderate" (that area looks very narrow on the photograph provided)
Then 2nd cliff to 200 feet which is almost vertical.

At Least that is my limited understanding. I don't think divers were covering the Spur zone, but were diving out past the spur zone.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 13, 2013, 01:56:55 PM
Hi All

Ric Can you confirm if this video was recorded at Niku 2010 expedition ?

 http://www.youtube.com/watch?v=iCs1r2TmRz4

Thank's Richie
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 13, 2013, 02:38:46 PM
Balderston Debris Field (red oval):

Title: Re: The Slope of the Reef around Nikumaroro
Post by: Greg Daspit on February 13, 2013, 04:35:01 PM
Some of  those areas do look dangerous for divers but difficult for ROV’s and dangerous for the ship.
Seems like divers are needed to get at hidden coral covered artifacts where an ROV could collide and cause avalanches, but any avalanche would be unsafe for the diver. The 2012 Debris Field seems accessible for divers but how do you safely search those areas?

If the underwater reef debris might be farther north how would it impact a Camp Zero search?
Seems like the bottom of that notch in the beach line is close to wherever the plane may have stopped in that zone and is a good place to look.
PDFs attached
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 13, 2013, 06:01:36 PM
Ric, you sound even more certain than I!
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 14, 2013, 02:33:53 AM
Jeff, I think Ric was describing the spur zone as different from the "not mapped" blackened area on his graph.
I think it goes like this from Rics latest description-

Reef flat 200 meters wide from beach to end of spur zone
Then spur zone(not sure how wide this entails)
1st cliff off the real shallow spur zone into 20-40 feet of moderate slope coral.(again not sure how wide this non mapped area is)
Then another dropdown to 100 feet of water where slope increases to "moderate" (that area looks very narrow on the photograph provided)
Then 2nd cliff to 200 feet which is almost vertical.

At Least that is my limited understanding. I don't think divers were covering the Spur zone, but were diving out past the spur zone.

Thanks, William.

I guess I'm still not so clear on it - it just looks from the photos showing the deep crags in the surf and the black unmapped zone that there might be fertile turf for hiding stuff there.

Well me and you both Jeff. Cause it's confusing.
 The graph from Ric which shows "unmapped" and "1st cliff" in black,  doesn't show how wide that is. It also doesn't show depth of the blackened in area.  In the graph there is also no spur and groove zone shown at all, it's all marked black. So is the spur and groove zone part of this unmapped area? How deep is it on the spur and groove zone and how much does it vary in water height during tides? Is there a drop off from the spur and groove zone into 20 feet of water or a slow transition?

In The video from Ritchie posted above, which is unmarked, he asks is this Niku 2010? Good question, because if it is it shows an ROV running right through this 20 foot depth marked with boulders and craggy peaks, and it looks like a small area, quickly dropping to 40 feet, then 100, then 400, ect. The shark in the video looks to be in about 40 feet of water, so that is too deep for a peek a boo plane. The boat seems no more than 400 meters from the beach, which is very interesting. (and brave)

Is the 20 foot deep boulder strewn nightmare of crevasses and holes part of the spur and groove zone seen clearly as WHITE/TAN in overhead photos? I do not think so.  From Ric's description and graph, the spur and groove zone is NOT the 20 foot deep area. If I am correct and understanding Ric, the 20 foot deep area suspected of holding the wreckage is just past the Tan colored spur and groove zone. The 20 foot depth is a fairly small LIGHT BLUE area before quickly dropping to DARK BLUE looking water as shown on overhead photos. The transition area from light blue water to dark blue water seems very small.

This transition area of 20 foot depth seems very small to catch a plane, it is not a broad flat expanse, and quickly drops to dark blue water 40-60 foot.  60 foot deep is too deep for the plane to be seen periodically.(unless it held air and was bobbing which I have doubts about)
So it is important to know just how much total area comprises this approximate 20 foot deep water which would seem the ideal depth for holding a peek a boo plane. Deeper than 20 feet and it gets problematic that Emily ever saw anything. More shallow than 20 feet and its basically on the reef flat or on the spur and groove section, and would be seen at every tide change and I don't see how Maude missed it.

An overhead kite photo(s) of the Bevington area, marked off with all snail trails, marked off with depths and cliffs, marked with width and area, showing water color transitions as it goes from shallower water, to darker blue water that is too deep to hold a plane that sometimes appears partially visible,  would be a wonderful thing to sort out the brain. We have the kite photo showing water heights on the reef, but not a kite photo marked up past the reef edge showing descending depths of the blue water.

Trying to make sense of things unseen with one's own eyes and based on descriptions, photos, maps and graphs and combine them all in the frontal cortex is a difficult thing.
I am sorry Ric if it's like talking to a kindergarden class, but there is still confusion.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 14, 2013, 07:26:28 AM
Very interesting comments Jeff. I have been looking at some of the reef photos that have been posted and found this one. The red "X" is the estimated location of "Nessie" at some time, I'm not exactly sure when. If you look at the area that I have enclosed with the "red rectangle" it looks like a hole in the reef. I don't know if it can be determined from old photos how long the "hole" has been there but if it has since 1937, it would seem, to me at least, this might be a place that could hold pieces of an Electra, maybe?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 14, 2013, 07:28:04 AM
Jeff after re-reading Rics description, and your thoughts, you may indeed be better tuned to the explanation suggested.
Viewing the kite photo, the light blue ocean starts half way up the groove zone. It doesn't get deep blue until the end of the spur and groove area..
So it could very well be the second half of the spur area is the area of 20  foot water, dropping to 60 foot water.
The first cliff could well be the end of the spur and groove area where Ric says it drops another 200 feet down to the 300 foot range.
300+ feet of water would fit nicely with the dark blue water shown just after the spur area.

Given that, then any spotting of wreckage would have to be before the first cliff, and indeed on the spur and groove section of reef. In fact, I think you are right in that Ric is referring to part of the spur and groove area as the unmapped area too dangerous to explore.

But that presents a problem, and you touched on it with Emily's description. Reading her words indicates to me she was describing rusty beam steel laying exposed at certain times of tide. Well that could not occur in 20 foot of water. If she was describing a wing sticking up, or a tail sticking up, then the majority of the attached superstructure could be in 20 feet of water.
However, It seems like she is describing something laying visible and relatively flat, a long rusty straight beam laying on rock quite exposed.
That would either be on the reef flat itself, or the first section of the spur and groove area. That would be quite shallow at times, perhaps a foot or three. A plane Fuselage wouldn't be hidden at any time in a foot or two of water at low tide.

So reading her description again sounds increasingly like norwich wreckage laying on the reef, in very shallow water less than 10 feet certainly, and  not in the 20-80 foot unmapped area.
At least that is the way I read her testimony.
Again, it doesn't mean there wasn't a plane even in 60 foot of water occassionally depositing a wing or skin.
It just means that from Emily's description she wasnt seeing huge sections of aircraft, or aircraft at all since she talks of beams laying  on rock. That all sounds very Norwich.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: william patterson on February 14, 2013, 07:44:32 AM
Nice photo woody and fits with Jeff's original thoughts that the rectangle section is still on the spur and groove section, though deeper water.
If that Hole is in 20-30 foot of water, and a plane ended there for a while, that all seems plausible.
It still doesn't seem to fit Emily's description in my opinion of  beams laying exposed.
She described beams "laying on Rock" only exposed at low tide, waves washing over it. Clearly this is the reef surface before a drop off.
That doesn't sound like a plane laying in a 20 foot deep hole, but laying on the reef surface itself or the first section of Spur and Groove where it is shallow.

 I am still with the possibility the rectangle may have held a plane for a while, I just don't think that is what Emily spotted.
Perhaps other islanders did spot something different than Emily, so while there may be legitimate spottings of stuck plane wreckage, and Emily may have heard those oral traditions of plane wreckage,
I don't think Emily's testimony fits with a plane stuck in a deep hole in the Spur and Groove area.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 14, 2013, 12:53:26 PM
Of course, without some independent scale, probably no-one would dare suggest that this shape might be a propeller. After all, there are still two missing.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 14, 2013, 01:05:06 PM
Or Nessie, Revisited?

 :)
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 14, 2013, 04:35:12 PM
Of course, without some independent scale, probably no-one would dare suggest that this shape might be a propeller. After all, there are still two missing.


If that was a propeller blade it would be the size of actual wingspan of Electra, Like you say scale is always an issue however if you go on Google earth an select ruler then select your preferred measurement ruler I.E miles meters inches etc obviously you need to know at what distance you are from reef surface to make it work.

One thing is bugging me if the Electra is resting somewhere in an area directly under nessie, If the accounts of possible wing debris are to be believed at entrance to lagoon how would it pass the rear end of NC ?

Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 14, 2013, 05:42:17 PM
One thing is bugging me if the Electra is resting somewhere in an area directly under nessie, If the accounts of possible wing debris are to be believed at entrance to lagoon how would it pass the rear end of NC ?

Tides, Northwest wind forces, scavengers, greedy crabs,...
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Greg Daspit on February 14, 2013, 06:26:52 PM
If the accounts of possible wing debris are to be believed at entrance to lagoon how would it pass the rear end of NC ?
I always figured it would pass in front of the Norwich City during high tides. Mainly because I suspected the aircraft skin artifact (http://tighar.org/wiki/2-2-V-1) TIGHAR found washed up or uncovered (http://tighar.org/Publications/TTracks/1992Vol_8/2_2_V-1.pdf) after a storm didn't float to the village area but was pushed there, because it didn't seem like it could float. Pushed across the reef.
This article (http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/56_WhereIsElectra/56_where2.htm) has some currents shown and I can see where it may go around the back. In that case the N.C. could have stopped stuff, more so before its stern fell off.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 14, 2013, 06:42:38 PM
...obviously you need to know at what distance you are from reef surface to make it work.


Richie, do you know whether that kite had an altimeter?

Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 14, 2013, 07:00:47 PM
I would imagine the kite only had a certain amount of tether so i guess Ric could answer this question.

As for sighting's am guessing the Bevington strut image, the parts of wing that was seen, along with the wheel that was spotted and the engine that possible was  air lifted to a Kanton dump site

Sort of makes sense, We have all the parts of a airplane wing possible tied down onto reef and then being snapped off by force.

I wonder if Jeff Glickman has been able to determine what side the strut is off ? 
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Dan Swift on February 15, 2013, 10:23:59 AM
Debris that washed up on the lagoon shore in the '50's (such as fuel tanks).  What happened to that? 
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ted G Campbell on February 15, 2013, 06:39:33 PM
To all,

Reference to G. Daspit’s comments (reply #26) brings to mind a question re the N.C.  Have we looked underwater near the up-current side of the N.C. to see if any aircraft parts may have come to rest against the “dam” of the N.C.?

Ted Campbell
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 15, 2013, 06:48:08 PM
To all,

Reference to G. Daspit’s comments (reply #26) brings to mind a question re the N.C.  Have we looked underwater near the up-current side of the N.C. to see if any aircraft parts may have come to rest against the “dam” of the N.C.?

Ted Campbell

Yes, and for too many days. And "up-current" depends upon depth: near the surface the current runs from Northwest to Southeast, while at greater depth (900-1000 feet) the current runs in the opposite direction. My "observation" and "speculation" is that aircraft and ship debris are not intermixed.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 15, 2013, 07:59:19 PM
Hi Ted G

Funny you should mention that, As there is a clip on the Finding Amelia 2012 video that shows NC debris, In this same clip there is a anomaly which i thought was the dead carcus of a fish. I Google planes underwater an found a similar object that was assumed to be dead fish which turned out to be shriveled plastic off dash board of a ww2plane
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Andrew M McKenna on February 15, 2013, 08:02:28 PM
Tim asks:

"Richie, do you know whether that kite had an altimeter?"

No, the kite camera did / does not have an altimeter.  Actually, it is an Olympus underwater / shockproof unit that does have a rough altimeter based upon ??, but I don't think that info is transferred to the photo, so in the end, no there is not any altimeter info available.

We probably had 2000 ft of kite line available, but in general most of the kite photography was taken from between 200 and 400 AGL.

Andrew
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Andrew M McKenna on February 15, 2013, 08:09:52 PM
Ted asks:

"Have we looked underwater near the up-current side of the N.C. to see if any aircraft parts may have come to rest against the “dam” of the N.C.?"

Tim refers to the deep water search of 2010, but also in 2001 we searched via SCUBA diving from the lading channel to near the NE tip of the island from the surf line to about 80 - 100 ft in depth, including all around the NC wreckage, so I'd say yes, we've covered the areas both "up and down current" from the NC.

Andrew
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 09:17:56 AM
I don't know if it can be determined from old photos how long the "hole" has been there but if it has since 1937, it would seem, to me at least, this might be a place that could hold pieces of an Electra, maybe?

Woody, would you be convinced if you could see parts of engine near by?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 16, 2013, 11:48:53 AM
I don't know if it can be determined from old photos how long the "hole" has been there but if it has since 1937, it would seem, to me at least, this might be a place that could hold pieces of an Electra, maybe?

Woody, would you be convinced if you could see parts of engine near by?

Tim, if I could "see" any type of aircraft part I would be convinced. I can't "see" any in this picture.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 16, 2013, 01:00:17 PM
Hi Tim

I don't see anything in your image see first attached pic

Second image shows a man made object in 2012 debris field for sure, Possible fan for removing fumes from fuselage.

Thanks Richie
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 01:37:06 PM
Ric, any idea what all this chain is from in the picture of the slope you posted in Reply #4 above?

Ah, yes! Now I remember where I saw chains before!


Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 02:02:45 PM
Seems to me that both oval stickers are visible on the nearer blade of the propeller: the sticker closest to the hub sits athwart the blade, while the red Hamilton Standard sticker lies parallel to the blade length. An un-annotated shot is provided for magnification, as well as a picture of the actual propeller on NR16020. It seems logical that a propeller might be found not too far from an engine.

Title: Re: The Slope of the Reef around Nikumaroro
Post by: don hirth on February 16, 2013, 02:50:06 PM
Richie, I would agree! What you call an "air duct fan" (whether that, or not) is NOT a natural
object in the scheme of things. Further, the pic. speculating the presence of a "prop" I find
very interesting as well as the "cowling and possible cylinders." Keep up the good work.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Andrew M McKenna on February 16, 2013, 03:26:09 PM
Tim

Once again I think that the lack of scale is misleading everyone.  Your prop would be about 40 ft long in my estimation.  I wasn't part of the team the day those photos were taken, but based upon typical flights the photos were taken from about 200 ft up, so the scale is much larger than you are imagining in your visualization of a prop.

Andrew
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 16, 2013, 03:38:58 PM
Tim

Once again I think that the lack of scale is misleading everyone.  Your prop would be about 40 ft long in my estimation.  I wasn't part of the team the day those photos were taken, but based upon typical flights the photos were taken from about 200 ft up, so the scale is much larger than you are imagining in your visualization of a prop.

Andrew

Thanks Andrew. I thought it looked like a "spur" of the reef and guessed it to be 50 ft.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 16, 2013, 05:10:53 PM
This is what a prop looks like after 70+ years in shallow coral reef tropical waters.  It's from a Brewster F2A-3 Buffalo at Midway.
Show me the stickers.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 16, 2013, 05:27:11 PM
And this is what a 2 propeller blade engine would look like after many years
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 16, 2013, 05:33:09 PM
And this is what a 2 propeller blade engine would look like after many years

Where is that Richie?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: richie conroy on February 16, 2013, 06:01:18 PM
http://www.news.com.au/national/suspected-ww2-bomber-found-underwater-off-magnetic-island/story-fndo4eg9-1226439588533
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 06:14:31 PM
Where is that Richie?

And the chains, Ric? Please explain the chains.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 06:19:03 PM
It's from a Brewster F2A-3 Buffalo at Midway.

How deep is that Buffalo, Ric? Is it comparable?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 06:25:11 PM
Thanks Andrew. I thought it looked like a "spur" of the reef and guessed it to be 50 ft.


Woody, in this game guessing, or "speculation", is not good enough. Ric has said so. You could theorize that it is an anteater, or a John Deere 310E backhoe, but "guessing" is just not good enough. Sorry.




Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 06:31:44 PM
Show me the stickers.

Here (red arrow) and here (amber arrow).
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 16, 2013, 06:52:30 PM
Tim

Once again I think that the lack of scale is misleading everyone.  Your prop would be about 40 ft long in my estimation.  I wasn't part of the team the day those photos were taken, but based upon typical flights the photos were taken from about 200 ft up, so the scale is much larger than you are imagining in your visualization of a prop.

Andrew

But Andrew, you don't know the altitude, do you? You admitted that the altimeter did not report on the film. So it is possible, isn't it, that he kite could have been at 50 feet, or 100 feet, or anything in between? So, very possibly, it could be a prop, couldn't it? And, of course, it could be a Bevington Object with bulimia, I suppose.

We must all be held to the same standard of intellectual honesty, after all.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Andrew M McKenna on February 16, 2013, 08:18:21 PM
Tim

You are right, I don't KNOW the altitude of the kite at the moment that it took the photo, but I do have direct experience flying the kite borne camera, and I have direct experience diving the grooves in the reef, including the area covered by these photos.  Based upon that experience, my estimate of the altitude is 200-300 ft.

Go back the the original photos posted in post #18 and look at the composite photo.   Think about how high the camera was to capture those images.  What you see is the surf line and about half the reef flat.  If the reef flat is say 150 yards between the surf line and the beach, you are looking at some 200 + ft of reef flat, and if that is the case, your prop is considerably bigger than you think it is.

Each of those grooves in the reef are some 6-8 ft across, big enough for a diver to swim up the groove to the surf line.  I know because that is exactly what we did in 2001, from the landing channel to near the NE end of the island, swam up every one of them.  If there was a prop there, we would have found it, especially if it was as big as you think it was.

So, no, I don't know the exact altitude of the kite, but I have direct experience to estimate that altitude, and I do know the scale of the grooves on the reef.  That experience leads me to dismiss your visualization of a prop in the photo as being realistic as I know the scale is way off.

Andrew

Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 16, 2013, 08:39:38 PM
And the chains, Ric? Please explain the chains.

I see no chains.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 16, 2013, 08:42:15 PM
It's from a Brewster F2A-3 Buffalo at Midway.

How deep is that Buffalo, Ric? Is it comparable?

The Buffalo debris at a depth of 8 to 10 feet.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Michael Elliot on February 16, 2013, 09:27:08 PM
re. chains

Chains were used in the flap mechanism of L-10s.
I would expect they were the same general structure as bicycle chains -- each sprocket hole has two cross bars and two side bars. That's my speculation, not fact.
Have sent a query to the guy that rebuilt CF-TCC.
Will let you know when I hear.

Mike
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 17, 2013, 01:01:44 AM
Mike, the chains that are apparent to me have forged one-piece links, totally unlike the bicycle chain you are describing. I don't think they arrived on the airplane by the lengths I can see. More likely from the Norwich City, IMHO.

Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 17, 2013, 01:31:25 AM

So, no, I don't know the exact altitude of the kite, but I have direct experience to estimate that altitude, and I do know the scale of the grooves on the reef.  That experience leads me to dismiss your visualization of a prop in the photo as being realistic as I know the scale is way off.

Andrew

There is certainly no equal to first hand experience, Andrew, so I must defer to your judgement here.

Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 17, 2013, 05:01:59 AM
And the chains, Ric? Please explain the chains.

I see no chains.

Perhaps we are looking at chain coral? (http://www.google.com/images?client=ms-rim&hl=en&q=chain+coral&oe=UTF-8&channel=browser&sa=X&oi=image_result_group&ei=t8IgUYroG6-10QHIt4H4CQ&ved=0CAcQsAQ)

Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 17, 2013, 12:02:35 PM
re. chains

Chains were used in the flap mechanism of L-10s.
I would expect they were the same general structure as bicycle chains -- each sprocket hole has two cross bars and two side bars. That's my speculation, not fact.
Have sent a query to the guy that rebuilt CF-TCC.
Will let you know when I hear.

Mike

Mike, here is a picture I got somewhere, sorry I no longer remember where, that appears to be of the crash of an L-10 Electra. The red arrow points to what seems to be the chain that drives the flaps.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 17, 2013, 12:32:44 PM
Mike, here is a picture I got somewhere, sorry I no longer remember where, that appears to be of the crash of an L-10 Electra. The red arrow points to what seems to be the chain that drives the flaps.

That's the Gillam crash in Alaska that we investigated.  The arrow points to a rivet line along a seam in the wing, not a chain.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 17, 2013, 12:53:02 PM
Thanks for the location Ric.
If you "blow up" the picture, I can do this on my computer but I cannot save the enlarged picture, it appears that the rivet line is below the "chain" as you look at the picture. There also, IMO, appears to be a motor, with a gear attached, at the black arrow.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 17, 2013, 01:23:06 PM
See attached detail from another view of the same feature.  No chain.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 17, 2013, 01:32:26 PM
See attached detail from another view of the same feature.  No chain.

OK. It also shows that there is no pump. Thanks Ric.

Are those rusty, steel rivets??
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 17, 2013, 05:11:59 PM
Are those rusty, steel rivets??

I think they're rusty steel screws.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Greg Daspit on February 17, 2013, 05:42:02 PM
Thanks for the input Andrew.
Its nice to have someone who was there to describe the reef.
From the Gillam Crash survey (http://tighar.org/Contract_Services/Gillam/Gillam05.html), in the cockpit photo there is a chain at the bottom.
With chains, wires and such, what methods could be used to recover debris that may be tangled/ buried/ overgrown in a steep area with a cliff above it?   
I imagine you would have to pick items up very slowly and only good candidates in the clear.
Anyone currently with TIGHAR with that kind of recovery experience?

Title: Re: The Slope of the Reef around Nikumaroro
Post by: C.W. Herndon on February 17, 2013, 07:45:48 PM
Are those rusty, steel rivets??

I think they're rusty steel screws.

Thanks.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 17, 2013, 08:59:56 PM
Anyone currently with TIGHAR with that kind of recovery experience?

Any recovery of underwater aircraft wreckage would be supervised by an experienced underwater archaeologist.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 18, 2013, 04:58:53 AM
BTW, is this an electrical junction box, or something else?
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Ric Gillespie on February 18, 2013, 07:20:31 AM
BTW, is this an electrical junction box, or something else?

I don't know what that is. 
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 19, 2013, 06:49:58 PM
I seem to recall seeing something like this electric junction box before, I just can't remember exactly where...

I will look through my scrapbook. Anyone interested need only PM me their email address.
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Michael Elliot on February 20, 2013, 01:19:02 AM
In Greg Daspit's post of Feb 17, his pic cockpit.jpg shows, in bottom center, chain as I described in an earlier post -- similar to a bicycle chain. Flaps require precise control in both extension and retraction, so cables are inefficient. Chains are much better for the task. The pic chain was most likely under the floor of c/n 1021.

Tim, I see your chains on the reef, but I don't think they are L-10 control chains. And, they're too long. (Did Lockheed Burbank use chains or straps to secure the extra tanks in the fuselage of c/n 1055?)

Regards
Mike
Title: Re: The Slope of the Reef around Nikumaroro
Post by: Tim Mellon on February 20, 2013, 04:34:59 AM
And the chains, Ric? Please explain the chains.

I see no chains.

Perhaps we are looking at chain coral? (http://www.google.com/images?client=ms-rim&hl=en&q=chain+coral&oe=UTF-8&channel=browser&sa=X&oi=image_result_group&ei=t8IgUYroG6-10QHIt4H4CQ&ved=0CAcQsAQ)
.                           

Mike, it appears to be chain coral that we are seeing on the reef; the links are too irregular and varied in size to be of human manufacture.


 :)