Advanced search  
Pages: 1 ... 72 73 [74] 75 76 ... 106   Go Down

Author Topic: Still from ROV video  (Read 1088116 times)

LWhite

  • Guest
Re: Still from ROV video
« Reply #1095 on: April 24, 2012, 04:55:51 PM »

Richie,
For better or worse, attached is my first attempt at stitching some pix together.  The pic is fairly large.  Try converting to grayscale to get a "1938" magazine look.  I've been swamped at work, so it took longer then expected. 

Added:  It will be best if you download the pic to view it.  When displayed here is at 100% but unmanageable.  Depending on your viewer you've got alot to see at 200% or 400%.

Leon
« Last Edit: April 25, 2012, 04:43:38 PM by Leon White »
Logged

Malcolm McKay

  • Read-only
  • *
  • Posts: 551
Re: Still from ROV video
« Reply #1096 on: April 24, 2012, 07:51:46 PM »


1. Jumping the gun in respect of naming i.e. Electra
2. Mistaken assumption to be investigated soon, that's why we're here
3. Here be dragons

Sorry but I rather thought I had made my scepticism in this matter quite clear. In fact if you read my second post regarding the completeness or otherwise of the Electra if it had landed on the reef you will note where I stated that I see a strong possibility that the aircraft wreckage recollection may indeed be a combination of native gossip and simply mistaking bits from the Norwich City for aircraft components.
Logged

richie conroy

  • T5
  • *****
  • Posts: 1412
Re: Still from ROV video
« Reply #1097 on: April 24, 2012, 08:16:06 PM »

if they were getting paid for there story, then fair argument..

but the Natives weren't used to seeing planes,

so there was no gain for them to make stuff up

so can u explain

how it was rather fortunate for Tighar that Emily's  recollection of what she saw on reef edge is matching of airplane description 

the post loss messages crossed in the vicinity on Niku

etc list goes on 

We are an echo of the past


Member# 416
 
Logged

Malcolm McKay

  • Read-only
  • *
  • Posts: 551
Re: Still from ROV video
« Reply #1098 on: April 24, 2012, 08:58:05 PM »

if they were getting paid for there story, then fair argument..

but the Natives weren't used to seeing planes,

so there was no gain for them to make stuff up

so can u explain

how it was rather fortunate for Tighar that Emily's  recollection of what she saw on reef edge is matching of airplane description 

the post loss messages crossed in the vicinity on Niku

etc list goes on

First rule of ethnography - establish what it is exactly that the people claim to have seen. So far that has not been achieved.   
Logged

Jeff Victor Hayden

  • T5
  • *****
  • Posts: 1387
Re: Still from ROV video
« Reply #1099 on: April 25, 2012, 05:39:18 AM »

Norwich City debris field in 1985.

A rust-colored something-or-other on the reef so close to the Norwich City might logically be thought to be shipwreck debris, except it’s in the wrong place. For most of the year the weather at Nikumaroro comes out of the east and is relatively benign, but from November until April (as we learned to our regret in 1997) immense westerly swells sometimes pound the island. The effect of these rare but devastating events can be seen in the progressive deterioration of the S.S. Norwich City. As the ship has broken up over the decades, the debris field has scattered west and southwest – never north.


http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/32_SatPhoto/Nikusatphotopage2.html

The chances of SS Norwich City debris ending up where the Electra was theorised to have touched down are slim to say the least. Native Gilbertese islanders could have moved some of the SS Norwich City debris to that location, for whatever reason, but that seems unlikely. Why would they do that?
From the ROV footage I have yet to come across anything robust enough to have come from a 1911 built cargo ship. In fact if any of the junk down there came from the SS Norwich City then, there was a shipyard in 1911 that was decades ahead of anyone else in terms of construction methods and materials. They could construct a vessel of Tonnage: 5587.08 Displacement: 8730 tons Length: 397 feet, using thin aluminium alloy and rivets that managed to even leave the shipyard would have been a miracle of engineering in itself.
Like you, I am not sold on the idea of a reef landing but, after spending some time with the ROV footage there is something down the reef slope that doesn't fit in with a coral reef or a 1911 ship. Of course at this stage it's still only speculation but, some time this year all will become clear one way or another.
This must be the place
 
Logged

Jeff Victor Hayden

  • T5
  • *****
  • Posts: 1387
Re: Still from ROV video
« Reply #1100 on: April 25, 2012, 06:36:31 AM »

Yes, aluminium doesn't rust, it corrodes. It will form an oxidisation layer which will protect the aluminium underneath from further attack.
Aluminium has a natural corrosion protection from its oxide layer, but if exposed to aggressive environments it may corrode

The following factors may affect the stability of the aluminium oxide and thereby cause corrosion:

• The oxide is not stable in acidic (pH < 4) or alkaline (pH > 9) environments [1].
• Aggressive ions (chlorides, fluorides) may attack the oxide locally.
• Certain elements (Ga, Tl, In, Sn, Pb) may become incorporated in the oxide and
destabilise it [4].

Pitting
Pitting is a highly localized type of corrosion in the presence of aggressive chloride ions. Pits are
initiated at weak sites in the oxide by chloride attack [4,5]. Pits propagate according to the reactions
Al = Al3+ + 3e- (1)
Al3+ + 3H2O = Al(OH)3 + 3H+ (2)
while hydrogen evolution and oxygen reduction are the important reduction processes at the
intermetallic cathodes, as sketched in figure 1:
2H+ + 2e- = H2 (3)
O2 + 2H2O + 4e- = 4OH- (4)
As a pit propagates, the environment inside the pit (anode) changes. According to reaction 2 the pH
will decrease. To balance the positive charge produced by reaction 1 and 2, chloride ions will migrate
into the pit. The resulting HCl formation inside the pit causes accelerated pit propagation.

http://www.sintef.no/static/mt/norlight/seminars/norlight2003/postere/gaute%20svenningsen.pdf

http://www.nautechmarine.co.nz/corrosion.html

So, in a nutshell Aluminium doesn't like saltwater, it doesn't like being in contact with other metals when in saltwater. The oxidisation layer will give some protection as long as it remains intact and un-disturbed by chemical reactions (with other metals) or movement. Movement breaks the oxidisation layer which leads to more corrosion and eventually structural failure etc...

Very similar to the propogation of stress cracks in airframes, once they start they keep going until...

Aircraft wrecks sat in lagoons or the bottom of oceans are protected from movement. Aircraft wrecks sat on reefs are not.

We use aluminium as sacrificial anodes on our narrowboats over here, they have to be replaced on a regular basis as they break down over time.Refreshing your sacrificial anodes every year is important

http://www.anodeoutlet.co.uk/blog/tag/narrowboat-anodes/#axzz1t3R9vIoa
This must be the place
 
Logged

Jeff Victor Hayden

  • T5
  • *****
  • Posts: 1387
Re: Still from ROV video
« Reply #1101 on: April 25, 2012, 06:49:10 AM »



Taking Care of your Aluminium Boat
 



Thousands of aluminium boat owners are not aware of how important it is to ensure their hulls are checked and maintained regularly. Owners have no hesitation in flushing the salt water out of their motor (to stop the aluminium corroding) yet may over-look the importance of flushing out their aluminium hull. It is a fact that aluminum boat corrosion is becoming more of a problem as time goes by, not because of the aluminium itself, but due to the lack of awareness and knowledge on how to take care of it.
 
Taking proper care of your aluminium boat will provide you with a life-long investment. Some common causes of corrosion in aluminium boats are detailed below, as well as how to identify any problems and avoid costly repairs.
 
Types of Corrosion

 
There are no mysteries in corrosion control, since the early 1800's scientists have been trying to solve the problem and it is understood that salt water is one of the most difficult environments in which to control corrosion.
 
It is important to note that corrosion in aluminium boats start from the inside out, so by the time it shows itself on the outside of the boat it’s usually a lot worse than a pin hole and will require professional repair.
 
Aluminium naturally develops a hard outer coating that protects itself against corrosion (oxide layer). However, where the stringers and bulk-heads sit on the hull there are crevices that can trap saltwater. This saltwater can break down the protective oxide layer, allowing corrosion to develop.
 
Lack of oxygen (oxygen starvation) can be another reason aluminium corrodes (ie; leaving saltwater sitting in the hull of your boat over a long period of time can cause tiny areas where the oxide layer is compromised, allowing corrosion that is evident as pitting).  Click here to view examples of corrosion caused by Oxygen Starvation.
 
Dissimilar metal fittings incorrectly installed to your hull (stainless rod holders, stainless fasteners, chrome plated brass fittings - even your anchor winch) and stray metallic objects, such as hooks, sinkers, swivels, coins, lying against the aluminium hull, cause corrosion when combined with moisture. Dissimilar metals cause galvanic corrosion when immersed together in saltwater.  Click here to view examples of Dissimilar Metal corrosion.
 
Stray current corrosion, where an electrical component or system is incorrectly installed or has a bad earth, will turn your boat into a huge battery, with the saltwater becoming the electrolyte: Aluminium Hull + Current + Electrolyte = Corrosion.  Click here to view examples of Stray Current corrosion.
 
How to Identify Corrosion
 
If you have a leak on the outside of your boat, there is definitely something more sinister happening on the inside beneath the floor.
 
If you can, lift up the floor of your boat and flush it with fresh water. Make sure all the internal drain-ways are free from build up of scum, leaves, sinkers, or an escaped pilchard. If you can see a white paste on the surface of the aluminium or a white powder forming in the joints, then it is a sign that corrosion is taking place and requires attention.
 
If you have a painted hull and the paint is blistering and peeling off around the fittings, or there is evidence of a white powder between the hull and the fittings on a non-painted hull, it is likely that galvanic corrosion is taking place.
 
If your boat is equipped with sacrificial anodes (zinc blocks) and they are not corroding, your hull more than likely could be!
 
Managing Corrosion
 
One of the most important things to do after each fishing trip is to flush out the hull of your boat with fresh water. Remove the bung, let the salt water empty then put a fresh water hose in there and let it fill up. If possible, do this before you take the boat home so it can swish around whilst on the trailer, then open the bung up when you get home to let it drain. Always leave the boat parked bow high and the bungs open - this enables the hull to completely drain and breathe, preventing sweating. Some wooden floors and outboard packers in and on aluminium boats may contribute to advancing the corrosion process, as the copper and chrome used in treatment of some timbers (CCA treated) reacts with the aluminium. Timber also absorbs moisture holding it against the hull, thus causing corrosion.
 
If your hull is painted, any chips, scratches or holes drilled through the hull will leave the aluminium exposed to the environment which will allow moisture to ingress between the paint and the hull. This will cause the paint to blister and peel off. It is important to seal any exposed areas to prevent corrosion forming.
 
It is okay to fit stainless steel fittings to your aluminium boat. However, if there is moisture present between the aluminium hull and the stainless fitting, the less noble metal (aluminium) will deteriorate while protecting the more noble metal (stainless steel). This can be overcome easily during the installation process by using a sealing product such as Sikaflex or Duralac to provide a moisture barrier between the two metals.
 
In summary, there will be no corrosion if there is no moisture present, so keep your boat clean and dry. Lift the floor at least twice a season to check your hull if you can.
 
This must be the place
 
Logged

Jeff Victor Hayden

  • T5
  • *****
  • Posts: 1387
Re: Still from ROV video
« Reply #1102 on: April 25, 2012, 07:31:58 AM »

Here's the 'black mark' again. I have subrtacted the background for the first 2 images to get a better resolution of the black mark itself.
The blue arrows point to the black mark but, notice the area around it, how clean it looks. Notice the edges of the black mark, sharp, thin. look at the shape it makes. The black mark is a void beneath something very thin which has split/torn.

This must be the place
 
Logged

LWhite

  • Guest
Re: Still from ROV video
« Reply #1103 on: April 25, 2012, 05:05:26 PM »

Malcolm,
(and with all due respect to all)-
I too believe  that if it went over, it went over in one piece, or in big pieces.  The possible boyancy argument seems to presume a safe landing in this environment, and a safe exit from the island.  Otherwise, if any of the undercarriage or skin gets ripped, the plane is likely to take on water.   

In an earlier post you said you have only seen things that look like coral in the ROV footage.  Is that still the case? 

I have a strong belief in the pictures we're seeing now as containing man-made guages, piping, etc.  And the scale seems to be narrowing down.  When you look at gauges, knobs, and the matching switches from the control panel, I would argue we're looking, in many of the photos, at cockpit pieces, but very, very close up. When I zoom in on some of the stills (like those I posted above) I see guage-like objects with black faces and white markings.

As to the plane staying in one or more big pieces - Wouldn't the rusting away of the rivets cause the plane to loose at least some of it's  conventional shape?

I have also researched a PBY cockpit, and it is no fit - very few guages, and mostly the big levers both on the floor and above.  If we think we can rule out the PBY in these photos, then we're left with a aluminum object with guages etc. that crashed before 1937, or after 1937  when nobody was looking.  WWII seems to be one of those times, as things were rather hectic then.  We could as easily suppose somebody dumped this wreckage in 2007 when nobody was looking ...

However - finding alot of items similar to the electra cockpit (including fuel lines), that are NOT from the cockpit seems a bit of a stretch too. 

I appreciate everyone's interest and intensity.  I don't want to perturb it however.  I have enough stress elsewhere.

Regards
Leon
Logged

LWhite

  • Guest
Re: Still from ROV video
« Reply #1104 on: April 25, 2012, 05:18:29 PM »

Attached are some comparison pix of electra guages to some object from the ROV footage. No way to know the orientation of the object from the ROV.

Leon
Logged

Malcolm McKay

  • Read-only
  • *
  • Posts: 551
Re: Still from ROV video
« Reply #1105 on: April 25, 2012, 07:36:43 PM »

Malcolm,
(and with all due respect to all)-
I too believe  that if it went over, it went over in one piece, or in big pieces.  The possible boyancy argument seems to presume a safe landing in this environment, and a safe exit from the island.  Otherwise, if any of the undercarriage or skin gets ripped, the plane is likely to take on water.   

In an earlier post you said you have only seen things that look like coral in the ROV footage.  Is that still the case?
Regards
Leon

Hello Leon

Yes that is the case, until someone actually comes up with pictures that have a scale and items that do not appear to be anything other than lumps of coral. I also note that that cautionary approach is also TIGHAR'S.
Logged

LWhite

  • Guest
Re: Still from ROV video
« Reply #1106 on: April 25, 2012, 08:55:06 PM »

Ok,
Then I think we need a working definition of "coral."  I'm not a marine biologist, so I'll have to leave the description to someone else.  However, for me coral is NOT

perfect right angles with sharp corners
Long straight lines (ruler straight)
wheels
shiny - like metal
smooth with regularly repeated holes of uniform size in repeating patterns
smooth symetrical curves (like the corners of passenger windows); that is, without irregular small bumps etc.
perfect circles or circular outlines
perfectly round black outlines with lighter colored markings.

There are more in my list of things that I won't accept as coral, but I'll stop there. 

What should a working definition be?

Leon
Logged

Malcolm McKay

  • Read-only
  • *
  • Posts: 551
Re: Still from ROV video
« Reply #1107 on: April 25, 2012, 09:24:25 PM »

Ok,
Then I think we need a working definition of "coral."  I'm not a marine biologist, so I'll have to leave the description to someone else.  However, for me coral is NOT

perfect right angles with sharp corners
Long straight lines (ruler straight)
wheels
shiny - like metal
smooth with regularly repeated holes of uniform size in repeating patterns
smooth symetrical curves (like the corners of passenger windows); that is, without irregular small bumps etc.
perfect circles or circular outlines
perfectly round black outlines with lighter colored markings.

There are more in my list of things that I won't accept as coral, but I'll stop there. 

What should a working definition be?

Leon

Hello Leon

Because there is no scale one has no way of assessing how "long" these long straight lines are. I'm sorry but nowhere in any of the pics from the ROV footage is there anything that has demonstrably straight lines, or smooth symmetrical curves but there are lots of bumpy lumps of encrusted coral.

At one stage someone was claiming to have found an engine, the cowl and the propellor right down to the manufacturer's decal on the propellor blades. Now given the nature of the pictures posted, and myself having an idea of what these objects actually look like, I was stunned to see that there was no questions asked at all about such a definite identification. I put that down to either ignorance or a polite wish not upset the person who made the claims.

These lumps, fragments and other amorphous chunks look like coral they don't bear any demonstrable resemblance to aircraft parts and none are shiny. Even the people at TIGHAR have cautioned against taking the ROV footage for anything else than a view of the reef. So until either a scale is placed in new footage and someone retrieves one of these blobs to prove otherwise then to me and I suspect many people, coral it is. I cannot understand why so much wishful thinking has been allowed to push the concept of proof aside. It doesn't help to advance TIGHAR's hypothesis.
Logged

Jeff Victor Hayden

  • T5
  • *****
  • Posts: 1387
Re: Still from ROV video
« Reply #1108 on: April 26, 2012, 05:17:56 AM »

Quote
Because there is no scale
This has been mentioned before and, discussed in detail. Scale is an issue as there was nothing noticed on the ROV footage except 'wire and rope' at the time it was made. So, understandably, the issue of scale wasn't deemed neccessary at the time. In hindsight if these 'lumps of coral' had been noticed at the time then, it would have been logical to send down a yard stick but, that's hindsight for you.
Quote
At one stage someone was claiming to have found an engine, the cowl and the propellor right down to the manufacturer's decal on the propellor blades
Anything that looks out of place for a coral reef is worth taking a closer look at. What they resemble or, might be, is speculation at this stage. It doesn't mean that is what they are 100% certain. That's why you will see words like could be, possibly and IMHO. Remember, there's only a few minutes of ROV footage, not very good at that but, that's all we have to go on. So anyone who expects to be shown an Electra or any other aircraft wreckage on a plate is living in cloud cuckoo land. Whatever is down there has 75 years worth of coral debris piled on top of it. The wave action on the reef at the surface will grind the coral to powder which decends downwards and will cover anything and everything, check out the steep drop offs and shelf positions on the site.
Quote
myself having an idea of what these objects actually look like
Let me guess 'lumps of coral'?
Quote
These lumps, fragments and other amorphous chunks look like coral they don't bear any demonstrable resemblance to aircraft parts and none are shiny. Even the people at TIGHAR have cautioned against taking the ROV footage for anything else than a view of the reef.

...

Finally, all will become clearer later this year. IMHO there is something on the reef slope that doesn't naturally belong there.
Notice the use of IMHO
This must be the place
 
« Last Edit: April 26, 2012, 05:34:14 AM by Martin X. Moleski, SJ »
Logged

Chris Johnson

  • T5
  • *****
  • Posts: 1069
  • Trying to give a fig but would settle for $100,000
Re: Still from ROV video
« Reply #1109 on: April 26, 2012, 05:49:15 AM »

Jeff

what would be interesting is to see other reef slope footage taken before this one so that we can compare exactly what the reef slope does look like.

Logged
Pages: 1 ... 72 73 [74] 75 76 ... 106   Go Up
 

Copyright 2021 by TIGHAR, a non-profit foundation. No portion of the TIGHAR Website may be reproduced by xerographic, photographic, digital or any other means for any purpose. No portion of the TIGHAR Website may be stored in a retrieval system, copied, transmitted or transferred in any form or by any means, whether electronic, mechanical, digital, photographic, magnetic or otherwise, for any purpose without the express, written permission of TIGHAR. All rights reserved.

Contact us at: info@tighar.org • Phone: 610-467-1937 • Membership formwebmaster@tighar.org

Powered by MySQL SMF 2.0.18 | SMF © 2021, Simple Machines Powered by PHP