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Amelia Earhart Search Forum => General discussion => Topic started by: Greg Daspit on January 11, 2017, 10:04:16 AM

Title: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on January 11, 2017, 10:04:16 AM
I need help to verify if Eric Bevington’s time entries in his Diary are coordinated correctly with time settings used in AutoCAD.
In 1937 would Gardner Island be under Daylight savings time?
I need to verify if the annotated settings in the attached PDF are correct (for 1937).
In his Diary Bevington writes:
“We got in by 11.30, both somewhat foot-sore – constant walking in the lagoon softens one’s feet. On return to camp, water reports were excellent, so we had a meal and pushed off to Nimanoa, having first raised the flag on the mast”
Based on this entry, I've done shadow studies starting at 11:30am but I’m not sure if Daylight savings comes into play.

Bevington seems to be at least trying to keep track of the correct time in this entry:
“ we crossed the date line this evening (180 degrees) at 6 p.m. so it will be Sunday again tomorrow as the clocks go back 24 hours. At 7 p.m. when time had really gone back to Saturday”

I also need help on C/n 1005. (For practice and test of methods) Any aerials showing its orientation? I saw someone recovered the tail section but does the wreck still show up on google earth, or archived images of google earth?
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on January 11, 2017, 11:17:11 AM
In 1937 would Gardner Island be under Daylight savings time?

I don't know, but I would be VERY surprised if the Gilbert & Ellice Islands Colony was using Daylight Savings time.

I also need help on C/n 1005. (For practice and test of methods) Any aerials showing its orientation? I saw someone recovered the tail section but does the wreck still show up on google earth, or archived images of google earth?

Attached are the original images I have.  I don't know where the thing is so I don't know where to look for it in Google Earth.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on January 11, 2017, 12:49:57 PM
These exhibits show the shadows for the hard parts only and hard parts with the tire. A fully inflated tire casts a shadow on the worm gear or the left side of the fork at various times of the day. At no time are both of them in light. In the Bevington Photo both areas are in light. For the shadows of the tire to not cover those areas, the tire has to be deformed similar to the tire in the Luke Field Crash. Attached is a concept study I did last year with a big gash in the tire and exhibits for the shadow study of the inflated tire.
Edit:
The image of the tire with a gash in it is from a camera 15' away so the perspective is different than the Bevington Camera
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on January 11, 2017, 12:53:32 PM
That's pretty compelling.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on January 16, 2017, 04:38:36 PM
Regarding the AutoCAD lighting study of just the hard components.
The time of the day that the worm gear is in sunlight and does not have a shadow on it cast by either the axle, hub or brake falls within a somewhat small window. The worm gear first gets sunlight at about 11:45am, although not lit brightly at all. It gets brighter and brighter afterwards as the sun angle changes, and then the brake starts to cast a shadow on it at 1:15pm. By 1:45pm the axle starts to cast a shadow. In my opinion what may be the worm gear in the Bevington Photo is well lighted except for area which may be underwater.

From his diary, the only time Bevington could have taken the picture was when they departed the island. He said he arrived back at camp at 11:30, had lunch, raised the flag and headed off. I’m not sure how long it takes to cross the reef but the ocean seems very calm in the photo.
  I would be interested to hear from expedition members on the forum regarding how much time they typically spent crossing the reef in calm waters and loading the skiff, or an estimate for loading a small boat.   What would be a reasonable time or window?
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on January 16, 2017, 04:51:26 PM
Attached is an exhibit to illustrate something interesting observed after positioning the components.
If the worm gear section has the same diagonal struts still attached like in the Luke Field Accident,  there is a physical constraint for moving that section right. A strut on the worm gear section can clash with the brake or hub on the fork section. Moving the worm gear left much starts to conflict with the tire as dimensioned in the study Mr. Glickman in the The Object Formerly Known as Nessie (https://tighar.org/Publications/TTracks/2013Vol_29/February_2013/The_Object_Formerly_Known_As_Nessie.pdf).
 Moving it forward conflicts with both the strut and with what may be the axle tip in front of the worm gear. Moving it back buries it in the tire. There is a very small range to position these 2 components.

Note that what is shown in the attachment has the rear part of the fender/ mud flap at the bottom. Different than the 2D illustrations in “The Object Formerly Known As Nessie” (larger part of the fender part on top).   The intent is to study the fenders in both configurations. Also note the worm gear in the 2 D illustrations is a different shape than what I have modeled in 3D based on 40650 . I suspect the 2D illustrations are based on a modified landing gear version that Mr Harney may have used as a guide in his drawings. If it helps in the future I may be able to provide graphics for these parts.

Here is where I could use some help:  It would be helpful if I had a picture of either fender part, where it is not attached to the fork. I’m interested to see if it is notched to fit the contours of the reinforcing on the fork or not. And if so how much.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on January 16, 2017, 05:11:28 PM
  I would be interested to hear from expedition members on the forum regarding how much time they typically spent crossing the reef in calm waters and loading the skiff, or an estimate for loading a small boat.   What would be a reasonable time or window?

Except on rare occasions we use the landing channel so we don't have to cross the reef.  During the Maude/Bevington visit there was, of course, no landing channel. RCS Nimanoa was tied off to Norwich City.  Walking from the beach out to the shipwreck takes, at most, ten minutes but breaking camp, loading the whaleboat, and conveying stuff out to Nimanoa is going to be done by the Gilbertese, not the white guys.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Jerry Germann on January 16, 2017, 10:12:48 PM
These exhibits show the shadows for the hard parts only and hard parts with the tire. A fully inflated tire casts a shadow on the worm gear or the left side of the fork at various times of the day. At no time are both of them in light. In the Bevington Photo both areas are in light. For the shadows of the tire to not cover those areas, the tire has to be deformed similar to the tire in the Luke Field Crash. Attached is a concept study I did last year with a big gash in the tire and exhibits for the shadow study of the inflated tire.
Edit:
The image of the tire with a gash in it is from a camera 15' away so the perspective is different than the Bevington Camera

Greg,

Really enjoy your study and images!
 In trying to grasp all that you are saying, I have a question. In your image I believe you portray the tire as having become separated or gashed to create the dark shadowed area, and reference the luke field accident.The tire would therefore appear too have differing tread heights, with each separated end,out of the norm. In the bevington image, it appears to me that there is a reflection in that shadowed area, and is similar to the reflection on either side of the remaining tire. Would there be a refection there if the tire was separated? It may be possible that a gash was cut in two places, some few inches apart and allowed that small section of tire to collapse inward and still allow a reflection from the side of the tire....but that reflective area also appears out of plane with what would be the sides of the tire. What are your thoughts?
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on January 16, 2017, 11:16:13 PM


Greg,

Really enjoy your study and images!
 In trying to grasp all that you are saying, I have a question. In your image I believe you portray the tire as having become separated or gashed to create the dark shadowed area, and reference the luke field accident.The tire would therefore appear too have differing tread heights, with each separated end,out of the norm. In the bevington image, it appears to me that there is a reflection in that shadowed area, and is similar to the reflection on either side of the remaining tire. Would there be a refection there if the tire was separated? It may be possible that a gash was cut in two places, some few inches apart and allowed that small section of tire to collapse inward and still allow a reflection from the side of the tire....but that reflective area also appears out of plane with what would be the sides of the tire. What are your thoughts?
For the sunlight to cover the worm gear and light the upper part of the fork, the part of the tire closer to the camera has to be lower than inflated height.  Dropping this section of tire down also creates a cave of darker area under the rear part of the tire. The shape of the tire needed is Very similar to the Luke Field Accident. The image attached was just a concept study to determine what was happening with the shadows. In that 1-16-16 study I just sliced the tire with a clean strait cut and lowered one section. I didn't get detailed in making it jagged. (yet) . Regarding the center arrow you annotated. The tire cut may be jagged and what your see may just be an edge, also note the inside of the tire appears light colored in the Luke Field image. It may be part of the inside tire not in shadow. I don't see that as very bright.

Regarding the left arrow you annotated. That area may be the brake or part of the fender overlapping the area of the brake. Still studying that spot.

Regarding what the arrow to the right is pointing to. I intend to model the larger fender on top. The larger fender has a brace on either side. I think with the small fender on top(the concept study I attached), there is not enough area reflecting. I also did studies where I modeled what I call the Harney fender which he drew about 2" longer than what the installation drawing showed. It was very close to matching the area reflecting but I don't think its dimensions were accurate. Preliminary studies suggest the larger fender needs to be bent down into the tire to reflect lighted area to equal that of what is seen in the Bevington Object. In the Luke Field Accident, the worm gear is holding down the tire.  I suspect that in the Bevington Object, the fender is bent down on top of the tire and the fender's brace may be holding down the tire. So what I intend to study is if the line you annotated to the right could be the fender brace.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on March 19, 2019, 12:30:17 PM
A question on another string came up about if the landing gear failed and consideration of that in tidal studies.

Based on the sun analysis of the Bevington photo, at least the upper part of the tire was significantly pushed in right next to the wheel hub. The deformity in the tire could be caused by the landing gear failure but it could also be caused by the tire being flat and the plane being pushed and twisted around on the reef. Then the landing gear failing after this and the worm gear getting stuck in the tire opening.
https://tighar.org/Projects/Earhart/Archives/Research/Bulletins/82_BevingtonAnalysis2/82_BevingtonObjectNewAnalysis.html


The possible “tire” in the Debris Field video from 2012 appears to show what might be the hub significantly extending up from what would be the tire. The proportions of what would be  the tire and hub in this object are right.
If this was the case it could be the tire was cut around the hub’s rim like paper being cut on the edge of the table.  If the tire was flat and the plane was pushed by tides sideways and also forward/back sharp coral might cut the tire from the hub like that. The coral almost acting like a can opener. The tire being the can and the hub the lid. Another analysis of the tides could include an assumption where a tire or both tires were flat.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Jim Zanella on March 19, 2019, 03:22:41 PM
Would it be worth it to evaluate the Luke Field broken landing gear using your methods? I am assuming we know when the pics were taken at Luke field. This would help validate your
Gardner island analysis.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on March 19, 2019, 07:04:45 PM
Would it be worth it to evaluate the Luke Field broken landing gear using your methods? I am assuming we know when the pics were taken at Luke field. This would help validate your
Gardner island analysis.

I don’t know the camera angles and distances at Luke Field. Jeff Glickman did a detailed analysis of the camera location and the object location and how they are oriented at Gardner Island. I used that data for my study but don’t have it for Luke Field.

I think to validate the study more it might be better to build an actual full size model and use a real camera just to validate the angles and positioning of the components. In the full size real model study you would not be studying shadows but just the angles of the components, specifically the fork. Once the components angles are validated you could then go back and check them again with the autocad model. This method would also allow you to do an “overlay” of an enlarged real photograph with the enlarged Bevington Photo to check the angles and sizes.

In Autocad you typically “zoom in” to see something better. It’s like you walked closer to the object. An “enlarged” Bevington Photo and the “zoomed in” Autocad image of the landing gear have different perspectives so you can’t do an overlay.


FYI for the autocad study multiple cameras were used. One to check the fork’s angles using a camera from where Bevington took the photo, hundreds of feet away. Using this camera, extension lines projected from the different angled parts of the fork had to be added just to see the angles from about 300’ away. You can actually see one of these leftover extension lines in an image in the report. (The one taken above the entire model including the Norwich City and shoreline.) Another autocad camera was set closer to the components to be able to more easily adjust their position. This was the “working camera”. Images from this camera are what you see in the computer rendered images. 

If the positioning is right then the rendering of the shadows would not need to be validated. (edit others have asked me this):  It’s not me guessing where the shadows are by “drawing” or “sketching” any of it. It’s a computer rendering of  a “model” based on the actual location, day and time the photo was taken. 
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Leon R White on March 20, 2019, 12:37:37 PM
Could someone refresh me on the details of how TIGHAR thinks the landing gear got into the nessie position?  If the tire is deflated, it didn't float with the gear part hanging below it.  If the tire deflated and some part of the gear caught on the reef, would it stay fast in the "tire showing" position? If the tire is torn, it isn't floating, but if the tire is OK it could be floating when the pic was taken? Did the entire assembly get dragged across the reef and then get stuck in a crevice in an upright position?  Understanding the story should explain, or at least not contradict, the theoretical position of the remains.  thanks to all.
Leon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on March 20, 2019, 03:51:41 PM
Could someone refresh me on the details of how TIGHAR thinks the landing gear got into the nessie position?  If the tire is deflated, it didn't float with the gear part hanging below it.  If the tire deflated and some part of the gear caught on the reef, would it stay fast in the "tire showing" position? If the tire is torn, it isn't floating, but if the tire is OK it could be floating when the pic was taken? Did the entire assembly get dragged across the reef and then get stuck in a crevice in an upright position?  Understanding the story should explain, or at least not contradict, the theoretical position of the remains.  thanks to all.
Leon
It’s my understanding the object is on the edge of the reef in very shallow water, in a few inches or less. It’s right next to where the reef starts to slope down and it gets deeper. There is also a hole in the area as seen in the video Tighar has on YouTube. I don’t know if an exact tide analysis was done for the window of time the lighting works. That window is around 1pm, give or take about ½ hour. There are several sharp edges that could get stuck in a groove or hole. Some broken struts could still be attached to the mounting bracket which may have broken off with the worm gear / oleo strut assembly. These parts would be hidden by the tire or under water.

A few possibilities for why it’s there:
1.   It’s not stuck and has been moving from somewhere else, maybe even kicked back up from a storm.
2.   It’s stuck in a groove, crack or hole. Maybe the same hole that might have contributed to the gear failing.
3.     The crew, in attempt to save the plane, somehow found a way to secure it, via the landing gear, to the reef. Contributing to it's failure.
4.   My favorite: It’s tangled up with something heavier that could survive the dynamic conditions there.  For example a length of one of the several control cables which ran to the engine located just above the landing gear. The other end of the cable still tied to the engine in the deeper water next to it. The engine being easily identifiable as an airplane part by Emily’s father and rusty as she remembered. Possibly it's the same aircraft cable John Mims saw a fisherman using as a fishing leader. This line may have held the gear there a while, flopping around a bit, sometimes lower in the water, until the fisherman cut it lose and it eventually tumbled down to the debris field ledge.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Jon Romig on March 21, 2019, 06:26:12 PM
Would it be worth it to evaluate the Luke Field broken landing gear using your methods? I am assuming we know when the pics were taken at Luke field. This would help validate your
Gardner island analysis.

I think to validate the study more it might be better to build an actual full size model and use a real camera just to validate the angles and positioning of the components. In the full size real model study you would not be studying shadows but just the angles of the components, specifically the fork. Once the components angles are validated you could then go back and check them again with the autocad model. This method would also allow you to do an “overlay” of an enlarged real photograph with the enlarged Bevington Photo to check the angles and sizes.


Hi Greg,

Nice work!

It might be possible to get AutoDesk’s help building a model. Their CAD/CAM BUILD Space is in my building in Boston and they accept applications for protects to utilize it, I think for free if non-commercial. See https://www.autodeskbuildspace.com/

They have an amazing array of robotic fabrication tools that can work with a variety of materials. In this case we might want to use something easy like high density foam - I am not sure we could create a “working” model (with moving parts) without a lot of difficulty.

The BUILD Space studio has huge windows to the promenade and I have seen lots of fascinating projects fabricated there. I also notice that it is fairly underutilized and they appear to like projects that capture the imagination of passers-by.

I can reach out to them if you think it is worthwhile.

Alternately, it could be built on a standard 3-d printer but it would have to be a large one - most design firms like mine have printers that are too small, although the model could be scaled down and still work, I think.

Jon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on March 22, 2019, 09:20:01 AM

It might be possible to get AutoDesk’s help building a model. Their CAD/CAM BUILD Space is in my building in Boston and they accept applications for protects to utilize it, I think for free if non-commercial. See https://www.autodeskbuildspace.com/

They have an amazing array of robotic fabrication tools that can work with a variety of materials. In this case we might want to use something easy like high density foam - I am not sure we could create a “working” model (with moving parts) without a lot of difficulty.

The BUILD Space studio has huge windows to the promenade and I have seen lots of fascinating projects fabricated there. I also notice that it is fairly underutilized and they appear to like projects that capture the imagination of passers-by.

I can reach out to them if you think it is worthwhile.

Alternately, it could be built on a standard 3-d printer but it would have to be a large one - most design firms like mine have printers that are too small, although the model could be scaled down and still work, I think.

Jon
I like the idea of foam as a medium for a large model.  The lighter the better because some system or a device ( like the adjustable arm to a lamp) would be needed to be able to make position adjustments. The fork has 4 different axis you need to align. Both the fork and worm gear assemblies need to be rotated about all axis as well as move vertically and horizontally in all directions. You would probably also need a monitor close to the model with a live feed from a video camera. The camera is too far away to go back and forth to check the image and make adjustments to positions.

As far as worthwhile doing this?  After doing close to a thousand rendering runs with the object in different positions I personally don’t think it’s needed. But some have asked me about an overlay and I think the large scale, real camera test might be the best way to do it.
 
I would caution to not get too much into modeling every detail because the distances involved don’t let you see them. At one point I considered buying a program from Autodesk that had attributes you could enter for both the Worm and the Worm Gear to model the teeth. This program is used to actually design worm drives. I finally decided to just make the teeth straight because you probably can’t tell they are enveloped (slightly curved) if you looked at them from 30’ away, much less from 300’ away.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on March 22, 2019, 09:25:58 AM
Gentlemen,
This sounds like a fascinating project.  Its greatest value would be in demonstrating how convincingly the Bevington Object matches the wreckage of the Electra gear assembly.  Despite all the excellent work by Jeff Glickman and Greg Daspit, to many people the object in the photo is still just a blob.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Leon R White on March 22, 2019, 05:02:18 PM
Greg, thank you for the recap of thinking so far on the arrival of the object.  Re: getting started with the model.  There is small plastic kit of the electra, configurable as AE's, that might serve as a starting place for some kinds of tests. However it is of typical small model scale. It does have gear tho it may be the later gear. But, there should be a number of TIGHARS that can build or modify a plastic kit landing gear.  I have said kit in storage.  Bigger scale and the autodesk work would be ideal as it could be 1:1 scale, of course.

Leon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on March 23, 2019, 07:30:54 AM
There is small plastic kit of the electra, configurable as AE's, that might serve as a starting place for some kinds of tests. However it is of typical small model scale. It does have gear tho it may be the later gear.

I have the kit.  The gear has only the tire, wheel and strut and includes neither the bull gear nor the later knuckle mechanism.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Leon R White on March 30, 2019, 12:45:57 PM
Great!  Now all we need is a TIGHAR to make a few parts out of plastic and we might have a replica - albeit very small.  Any takers?

Leon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on March 30, 2019, 01:42:19 PM
I don't think such a tiny replica would be much use.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on March 30, 2019, 02:01:21 PM
A small scale model of the hard components of the landing gear would be easier to work with. My main concern is what would be the difference between a camera set at the closer scaled distance compared to Bevington’s camera?
A small scale model would also be easier to do a shadow study on a real model because you could model the deformed tire in clay.  (Autocad not good for this) All of this mounted to platform with sun dial to be adjustable to match azimuth and altitude learned from the Autocad study.
What’s needed to get it 3d Printed?
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on March 31, 2019, 08:05:58 AM
This is what the gear parts of the plastic model look like.  As you can see, the struts/forks are about 7/8 inch long. There is no bull gear. I'll be happy to send the model if it would be of any help. 
We have no 3D printing capability here at TIGHAR HQ.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 01, 2019, 11:34:59 AM
The BUILD Space studio has huge windows to the promenade and I have seen lots of fascinating projects fabricated there. I also notice that it is fairly underutilized and they appear to like projects that capture the imagination of passers-by.

I can reach out to them if you think it is worthwhile.

Alternately, it could be built on a standard 3-d printer but it would have to be a large one - most design firms like mine have printers that are too small, although the model could be scaled down and still work, I think.

Jon
Jon, I should have addressed my previous post to you since you might have access to 3D printers.

Do you know what would be needed to get a 3D printed model?
A 1:12 model would have the longest dimension of the model be about 3 ½” inches.  We could make the scale so it is slightly smaller but that seems like a workable size.
I don’t know about 3D printing but read that AutoCAD models can be used. It is better if they were modeled with solids. (I guess because the program tries to figure out how to carve an interior surface?)
Unfortunately the AutoCAD model I built has a lot of sections that are hollow (Hollow tubes for struts like the real components.) so it may not work.

Advantages to a scaled model method:
Can use real camera so you could do an overlay of an enlarged photo with the Bevington enlarged photo.
Small scale allows the tire to be formed more easily than in AutoCad (Using deformable material like clay). This would allow the study of the shadows instead of just angles of the fork.
Can do most of work indoors with single point light source before taking it outside.
A tilt table can allow the position to match the azimuth and altitude at Gardner on Oct 15 as long as the actual sun used when photographed is in reasonable position. See attachment:

A full scale study of just the hard components may also be done but that would need a big printer.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Bill Mangus on April 01, 2019, 02:34:20 PM
I don't know if this will help the discussion but I'll throw it out for consideration.

The following is a link to a site which has for sale a 1/53 scale model of the Electra.  They say it's backordered but no delivery expected.

1/53 scale is an odd scale from the more normal and "standard" 1/32 and 1/48 scale plastic model aircraft.  I don't know if this is the same kit Ric has.

              https://www.scalehobbyist.com/catagories/Model_Aircraft/amelia-s-lockheed-10-electra/WIL00053598/product.php?kw=lockheed,electra

Here's a picture of the boxtop art:

              https://www.scalemates.com/products/img/2/5/4/951254-15126-75-pristine.jpg

Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on April 01, 2019, 02:37:15 PM
Different box cover.  Same Williams Bros. model.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 01, 2019, 04:09:49 PM
Attached is an exhibit to show some examples for why the model needs to be more detailed than the kits.
 Some details like the diagonal angle on the worm gear are significant. At 12 noon it casts a shadow. At 1pm the protruding angle’s edge is in line with the angle of the sun so that it hardly cast any shadow. By 1:15 the angle is still not casting much of a shadow but the brake starts to cast a shadow. These images were part of the hard component study where the tire was removed to see if the hard components eliminated the landing gear as being the object.

The exhibit shows the main components needed.
I added the landing gear mounting bracket to a components needed since it may be under it and provides a point of contact for it to be sitting on a flat surface and not any part in a hole.

One other advantage to getting these 3D printed in full size is that divers on future expeditions can have real life mock ups on board to help with scale. It may help when looking at all that coral.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Walter Runck on April 04, 2019, 06:09:29 AM
A couple of thoughts about a physical model of the gear:

1.  File format.  3D printing requires the source model(s) to be in a .slt or equivalent format (from stereolithography, the original technique where you selectively harden liquid goo by zapping it with a laser).  I can probably do the conversion from the native AutoCAD if you find a printer to use.  Most printers now use a filament that's melted at the tip as it's fed out.  Think weed eater line being passed through a small torch and dripping out in very small but well-placed drops.

2.  If you want a full size model, why not have a machine shop do one out of metal?  This stuff was designed for 1930's manufacturability, so it appears to be a weldment of mostly bar stock with some gussets and finished diameters.  I don't have the Lockheed drawing, but unless it was a forging, it would be a small project for a job shop or even a hobbyist with a saw, a lathe and a welding machine.  Even if it was a forging, we don't need the strength since we're just looking at geometry and possible deformations so a lightweight mockup would do. 

3.  Find a set of gear for sale or loan.  There was some lying around up in Alaska a few years ago as I recall.

Nice work on the shadowing study.  It is hard to follow how the components end up in the modeled positions from their as-built arrangement i.e. what bent or broke to hold them where they appear in the assumed position?  Is there a thread I missed that explains the thinking?
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on April 04, 2019, 09:47:20 AM
3.  Find a set of gear for sale or loan.  There was some lying around up in Alaska a few years ago as I recall.

Recovering anything from the Alaska wreck would be virtually impossible. Attached are photos from the wreck in Idaho.  You wouldn't believe how heavy this stuff is. Gotta be over a hundred pounds.   Recovering these pieces from the ravine would take a Jeep with a winch and about a quarter mile of cable. Then you'd have to figure out how to get them home. 

Nice work on the shadowing study.  It is hard to follow how the components end up in the modeled positions from their as-built arrangement i.e. what bent or broke to hold them where they appear in the assumed position?  Is there a thread I missed that explains the thinking?

In the Idaho crash, on one side, the oleo piston on the fork pulled out of the strut.  On the other gear, the assembly stayed together.
In the Luke Field crash, the shaft of the oleo piston broke. The worm gear on the upper strut twisted around and cut open the tire.
That appears similar to the disassembly implied by the Bevington Photo.
 
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Jon Romig on April 05, 2019, 08:13:53 PM
The BUILD Space studio has huge windows to the promenade and I have seen lots of fascinating projects fabricated there. I also notice that it is fairly underutilized and they appear to like projects that capture the imagination of passers-by.

I can reach out to them if you think it is worthwhile.

Jon
Jon, I should have addressed my previous post to you since you might have access to 3D printers.

Do you know what would be needed to get a 3D printed model?

I will talk to the folks at the Build Space on Monday.

Jon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: James Champion on April 06, 2019, 08:03:33 AM
In one Bonus Feature film clip from from the show "Ice Pilots NWT" (Buffalo Airways), they recovered the landing gear from an old crash site of an Electra they once flew. Years previously it flipped-over when landing on a dry lake bed and burned with no fatalities. So, Buffalo Airways has one with the big toothed gear somewhere among their stuff.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Walter Runck on April 06, 2019, 01:48:20 PM
In one Bonus Feature film clip from from the show "Ice Pilots NWT" (Buffalo Airways), they recovered the landing gear from an old crash site of an Electra they once flew. Years previously it flipped-over when landing on a dry lake bed and burned with no fatalities. So, Buffalo Airways has one with the big toothed gear somewhere among their stuff.

That's what I was trying to remember.  I emailed the company about 5-6 years ago and never got a response.

Not that trying to drag a set out of the Idaho crash site looked too challenging, but maybe UPS Heavy would be a little more straightforward.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Jon Romig on April 07, 2019, 09:23:33 AM
What are the approximate diameters of the wheel and tire?

Thanks,

Jon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 07, 2019, 07:01:06 PM
What are the approximate diameters of the wheel and tire?

Thanks,

Jon
The undeformed tire diameter is 35".  The wheel hub is 6".
The tire in the Bevington photo is sort of "G" shaped instead of "O" shaped so it does not have a consistent diameter.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Randy Conrad on April 10, 2019, 10:40:34 PM
Good Evening Guys!!! I was reading Greg's post just now and remembered something that was presented several years ago on the forum. Is it possible Ric, that the Bevington photo of the landing gear became part of the G feature you guys found? Also, I saw the new photo layout for Tighar...nicely done. With that said...if the rocks laying on the beach like your picture shows...and Amelia did land...what scenario would we have if she was to dodge a whole set of rocks coming right at her? She would have braked super hard and would have had to go left or right...and thus causing a chain of events to happen! Something to think about!           

https://tighar.org/wiki/G_feature
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 11, 2019, 03:47:52 PM
Good Evening Guys!!! I was reading Greg's post just now and remembered something that was presented several years ago on the forum. Is it possible Ric, that the Bevington photo of the landing gear became part of the G feature you guys found? Also, I saw the new photo layout for Tighar...nicely done. With that said...if the rocks laying on the beach like your picture shows...and Amelia did land...what scenario would we have if she was to dodge a whole set of rocks coming right at her? She would have braked super hard and would have had to go left or right...and thus causing a chain of events to happen! Something to think about!           

https://tighar.org/wiki/G_feature
"G” shaped is just my description of the estimated tires shape. My estimation is it is similar to the shape of the tire after the Luke field accident based on where the shadows fall, and could not fall if fully inflated. The "G feature" is just off the lagoon on the other side of the island and not near the reef where the Bevington photo is.  Interesting how close the "G feature" is to the Bushnell survey points.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 11, 2019, 03:56:41 PM
Here are two experiments proposed to further test the Bevington Photo:

1.   The full size mock-up experiment. It would just include the worm gear and the fork with wheel hub without tire.  The goal is to test the angles and size of the hard parts by doing an overlay using a real photo of the mock up to compare with the Bevington photo. The photos would be taken from the same distance so the perspective is the same. The material used in the mock-up will be better if it was lighter. This is because you will need to adjust and support them in different positions. This could take multiple attempts. If the mock-up is heavy like the real thing, then support structures become a bigger issue. I’m thinking a lightweight box frame with fishing line to support the fork below it. The worm gear can have a simple brace mounted to the unseen side. ¾” plywood painted a reflective color can be used for the worm gear. PVC pipe may work for the fork.  I don't think it is realistic to do a shadow test with tire and fender full size. This is why the virtual AuoCAD experiment was done.

2.   The small scale mock-up experiment. Goal is to test shadows of the tire and fender by using a small amount of clay that can be deformed.  It can be worked on inside with artificial light source so becomes realistic.  Something like clay or Super Sculpey can be used to work on the fender and tire. Polystyrene pipe shapes and sheet from a hobby or model railroad shop can be used for the hard parts. Once done, a real photo could be taken from a scaled distance and an overlay test done. Not sure how scaled distance affects the perspective?

The tire would not be something that needs to be 3D printed in any of the two experiments since its shape would have to be estimated by trial and error in a material that can be deformed. The Autocad experiment shows the tire had to be deformed.
I’m willing to work on the small scale model experiment and even build it from scratch.   I can assist with dimensioned drawings if someone want to take on either building a full size mock up or a small scale mock up.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Leon R White on April 29, 2019, 05:31:32 PM
Ric,
Has anyone attempted to perform any analysis of the image portion that is in the water below the object?  Was a decision made that said analysis was of no use?

thnks
Leon
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Ric Gillespie on April 30, 2019, 07:22:59 AM
Has anyone attempted to perform any analysis of the image portion that is in the water below the object?  Was a decision made that said analysis was of no use?

We can't analyze what we can't see.
Title: Re: Landing Gear and Bevington Object shadow study
Post by: Greg Daspit on April 30, 2019, 09:48:14 AM
Ric,
Has anyone attempted to perform any analysis of the image portion that is in the water below the object?  Was a decision made that said analysis was of no use?

thnks
Leon
If by “below the object” you mean light colored areas on the lower part of the image, some analysis was done but it was not intentional. When assigning the surface material as water in Autocad the light area in the rendered image “below” what would be the fender consistently showed up as a wave distorted reflection of the fender.

  The light areas to the lower right of object could be splashes or other objects but there is not enough there to do an analysis of. By that I mean there is no combination of light areas and dark areas that you could compare to something. It’s mostly light areas and no discernible dark areas. My guess is it’s a piece of reflective material so low in the water it doesn’t cast a discernible shadow or it’s a splash of water.

Title: Re: Landing Gear and Bevington Object shadow study
Post by: Leon R White on April 30, 2019, 10:04:40 AM
Thank you Greg. 
Ric, there is part of the image below the 'object.'  I didn't say it was a plane, or a camel, or a banjo, or anything.  I said IMAGE.  Gee.