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AuthorTopic: LaPook Hypothesis: Box Search around 157-337  (Read 185448 times)

Gary LaPook

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• Posts: 1624
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #15 on: June 07, 2012, 01:12:28 AM »

Hey Gary...Adam here...want to tell you I appreciate your putting forth your ideas to critique, and I always respect when people with expertise bring their ideas to bear.

Here's the thing:  you have a navigator who's been up for 24 hours straight, there's limited fuel and...here's the kicker:  the noise of the engine makes complex direct two-way communication well-nigh impossible.  So, yes, in THEORY, one could execute a search pattern.
To me, whatever they did, given the limits in time, extreme likelihood of error owing to fatigue, stress and fear, and the inability to really communicate, it would have had to be kept simple.
You make it sound so complicated, it's not and all the planning can be done at the beginning so no work needs to be done during the search itself. An expanding square search pattern consists of legs that are at right angles to each other so each leg is followed by a ninety degree turn, all in the same direction. The first two legs are flown for twice the visibility, the next two for four times the visibility, then six times visibility then eight times visibility, etc. A simple example will  make this clear. They have been flying on a course of 157 degrees at a ground speed of 120 knots and the visibility is 20 NM. (We will ignore the wind correction angle for this illustration but that is easily allowed for in computing the headings to use to maintain the desired courses.)

At 1912 Z they have a four hour reserve of fuel and they know that they must have missed Howland. Noonan passes a note to Earhart.

"Turn left now to 067 degrees and maintain that heading until 1932 Z.
Then turn left to 337 degrees and maintain that heading until 1952 Z.
Then turn left to 247 degrees and maintain that heading until 2032 Z.
Then turn left to 157 degrees and maintain that heading until 2112 Z.
Then turn left to 067 degrees and maintain that heading until 2212 Z.
Then turn left to 337 degrees and maintain that heading until 2312 Z."

The first two legs take 20 minutes and cover 40 NM, twice the visibility. The next two legs take 40 minutes and cover 80 NM, four times visibility, the next two legs take 60 minutes and cover 120 NM, six times visibility. At the end of the four hours of fuel they have searched a box 160 NM on a side covering 25,600 square nautical miles, basically 80 NM in each direction from the starting position.

Rather than me drawing a diagram, see flight navigation reference materials available here.

gl
« Last Edit: June 22, 2012, 10:44:01 AM by Gary LaPook »
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Gary LaPook

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• Posts: 1624
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #16 on: June 07, 2012, 01:24:06 AM »

"Because of this, the obvious choice was to expend all fuel available to find Howland, not to fly off across 400 SM of ocean with their fingers crossed that they would bump into one of those islands."

I'm curious about this statement of yours, Mr. LaPook. Why is this the "obvious" choice. What makes this the "better" choice than what they may have ended up doing, flying southeast and landing at Gardner Island? Let me ask you a question, and I am being completely serious. It is an either/or question, just like the one Amelia and Fred faced 75 years ago:

----- Do you want to be stabbed, or shot? -----

Your first reaction is probably neither, correct? But what if those are your only choices? And you have to choose one or the other right now?
• Stabbing involves a lot of pain, blood, tissue damage, possibly even death if done with a big enough implement, enough times or in the right place.
• Shooting involves a lot of pain, blood, tissue damage, possibly even death if done done enough times or in the right place, or with a large enough caliber weapon.
Which is the more "obvious" choice now, Mr. LaPook? Which one gives you a better chance of coming out alive? What other factors come into play in your mind that I can't possibly be aware of?

You weren't in that cockpit 75 years ago. Neither was I, for that matter. I don't even want to begin to imagine how Amelia and Fred felt at 20-plus hours when all they saw below them was blue ocean instead of the brown smudge of Howland Island and the white speck of the Itasca.

But flatly stating that the "obvious" choice was to do one thing, with the benefit of 20/20 hindsight, to the outright exclusion of all other evidence, thoughts, information, etc., on the topic, is, to a certain extent, intellectually dishonest. Regardless of how adept you may be in your own chosen field, and I have absolutely no doubt that you are, we can always learn from others.

LTM, who knows what he doesn't know,

Monty Fowler, TIGHAR No. 2189 CER
I'll throw it back to you. Why do you think they would have considered, based on the information they had available to them at the time, that they would have a better chance for survival by flying SSE until the fuel was exhausted?

Without making an exhaustive list of the information they had available, they believed that the closest land was Howland based on their navigation. Even though their radio had not been useful so far, they had finally received a signal from Itasca and, given some more time and effort, it may yet prove to be effective. The Itasca is there so if they don't reach Howland it will be close enough to rescue them. There is a runway there, fuel, people and a successful flight if they find it.

Your choice, turn your back on all this, (and more,) and blindly fly off towards the SSE with the knowledge that any islands in that direction are likely to be about 400 SM (350 NM) away, are widely scattered, not knowing how big any of those islands might be or how difficult they might be to spot. Knowing, that based on the visibility they are experiencing, that they could fly through the whole Phoenix group without seeing any one of the islands (ask Rickenbacker) and the visibility might be worse in the Phoenix islands, they have no way of knowing. There is no way to fly a search pattern in the vicinity of the Phoenix group because they would not know when to start one since they do not know how long it will take to get there since they don't know where they are starting from. Even if they could determine when to start a search pattern they would have very little fuel remaining to make the search with.

And you can't follow the LOP since there is no way to determine that you are staying on it, even Ric agrees with this, you only have dead reckoning, maintaining a heading, and you can't dead reckon if you don't know where you are starting from. Also see what I wrote here.

So, just fly SSE until the engine quits with your fingers crossed, hoping to bump into an island. Is that YOUR obvious choice?

See what I wrote previously here.

gl
« Last Edit: June 07, 2012, 04:18:56 AM by Gary LaPook »
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Chris Johnson

• T5
• Posts: 1069
• Trying to give a fig but would settle for \$100,000
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #17 on: June 07, 2012, 02:42:35 AM »

"I thinking had a different image in mind for what I was looking for.". Marty, this is something I think AE and FN also had a problem with. In searching for a tropical island with an airport would AE have imagined a lush tree covered island with neatly cut out runways when looking for Howland?  Could they in fact have "had a different image in mind". Howland was without trees, no real height above sea level and two runways running from one beach sidebof the island to the other beach side.  Quite unlike anything she had ever landed on before. Yes Itaca was there spewing smoke but I wonder.....

Marty/Irv

do we know if AE/FN had seen any images of Howland? Shots taken from the air so that they had some idea of what they were looking for?
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Martin X. Moleski, SJ

• Posts: 3006
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #18 on: June 07, 2012, 03:39:37 AM »

do we know if AE/FN had seen any images of Howland? Shots taken from the air so that they had some idea of what they were looking for?

I don't know.

LTM,

Marty
TIGHAR #2359A

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Chris Johnson

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• Posts: 1069
• Trying to give a fig but would settle for \$100,000
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #19 on: June 07, 2012, 04:09:38 AM »

Its one thing looking for something that you know such as the model plane or my cross, another when you don't know what it is or have only an out dated chart or such like.

Suppose i'm thinking that by doing the box search, spotting an island with ship such as Garndnet may have given the impression of Howland.
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Martin X. Moleski, SJ

• Posts: 3006
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #20 on: June 07, 2012, 05:30:40 AM »

... spotting an island with ship such as Gardner may have given the impression of Howland.

For a moment, perhaps.

The illusion would not last long.
LTM,

Marty
TIGHAR #2359A

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John Ousterhout

• T4
• Posts: 487
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #21 on: June 07, 2012, 08:41:08 AM »

I still struggle with the thought of anyone intentionally flying 350 NM away from the vicinity of their destination.  I live in Washington State, which is less than 300 miles from border to border.  That's like someone who can't find Portland International Airport, so they fly all the way across Washington state to land in Vancouver BC.  That might make sense for a large fast airliner, but not a 120 mph twin.
If they have any working navigational abilities, I would expect some sort of local search pattern beginning at their calculated position.  If they don't have nav capabilities, I would still expect a search pattern, this time based on their best guess position.  The shape of the implied search pattern associated with each scenario might be different.  If a navigator was certain of their position, with a known margin of error, then the search area might be limited to that known margin of error.  In that case, the assumption might be that the destination had been overlooked, so the assumption might be that the search pattern needed to be repeated.  Marty's search for the RC aircraft is a good example - initial search of the area missed it (been there, done that, numerous times).

The second scenario, in which the navigator cannot determine their position, implies a search pattern that expands indefinitely, but does not repeat.

There is a hybrid scenario, in which one axis of their position is known (or confidently assumed), but the other axis is questionable.  Rather than flying an expanding box pattern, this scenario implies a rectangular pattern, only flying a limited distance from the known axis, while flying increasingly long legs parallel to that axis.

None of these scenarios allow AE/FN to fly patterns that eventually lead to a 350 mile leg - they didn't have the gas.  If they arrived at Gardner, it seems to me that it must have been the result of a terrible error in their DR navigation to the advanced LOP, and failure to determine even approximate position in daytime.  Gardner would need to be within the 160-mile box that Gary described, implying arrival at the LOP nearly 200 miles south of Howland!
Cheers,
JohnO

« Last Edit: June 07, 2012, 08:10:05 PM by John Ousterhout »
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Irvine John Donald

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• Posts: 597
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #22 on: June 07, 2012, 08:51:19 AM »

I don't think anyone is suggesting that they got to a point in their journey and said "Well Howland should be right there in front of us. It isn't so let's just fly south and see what happens.". I speculate that pilots doing DR reckoning often miss their target a little and have to search a bit to acquire it.  I further speculate that AE and FN did some form of search when AE radioed that "we must be on you" message.  What the search was our duration is unknown but I can't believe no search was done.
Respectfully Submitted;

Irv

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Irvine John Donald

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• Posts: 597
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #23 on: June 07, 2012, 08:58:35 AM »

do we know if AE/FN had seen any images of Howland? Shots taken from the air so that they had some idea of what they were looking for?

I don't know.

Were any aerial shots of Howland even available?  What aircraft would have taken it?  Not a well travelled area.

Remember that search pilot Lambrecht said the island had short bushy trees and so his interpretation of the scale (actually 80 foot tall trees) was off. Could that also be that AE saw a "sandbar" and dismissed it because her scale was wrong and it didn't look like a typical tropical island (no trees and a scant 6 feet above sea level is the maximum elevation)?
Respectfully Submitted;

Irv

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Jeff Victor Hayden

• T5
• Posts: 1387
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #24 on: June 07, 2012, 09:56:27 AM »

At 08:43 Earhart said, “We are on the line 157 337. Will repeat this message on 6210.”

At 08:55 she said, “We are running on line north and south.”

http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/49_LastWords/49_LastWords.html

Do these two statements sound like the start of a search pattern? Gary?
IMHO they do, “We are running on line north and south.”. North AND South? North, turn 90, South, turn 90 as in Garys example of an expanding box search pattern.
This must be the place

« Last Edit: June 07, 2012, 10:01:29 AM by Jeff Victor Hayden »
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Edgard Engelman

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• Posts: 12
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #25 on: June 07, 2012, 12:20:04 PM »

The "must be on you" message was logged at 07:42, one hour before the "on the line" message. Most probably AE was 'searching' during that hour. Exactly was form this search took, is another problem (only north and south or a rectangular pattern); it is the ltime lag between the 2 messages that also suggest a search pattern.
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Jeff Victor Hayden

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• Posts: 1387
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #26 on: June 07, 2012, 01:07:51 PM »

The "must be on you" message was logged at 07:42, one hour before the "on the line" message. Most probably AE was 'searching' during that hour. Exactly was form this search took, is another problem (only north and south or a rectangular pattern); it is the ltime lag between the 2 messages that also suggest a search pattern.
That sounds like a reasonable explanation Edgar. That would have given them time for a few North South sweeps with the accompanying 90 degree turns.
This must be the place

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Chris Johnson

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• Posts: 1069
• Trying to give a fig but would settle for \$100,000
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #27 on: June 07, 2012, 01:11:54 PM »

When discussing the LOP on another thread I was told that you could not accuratly fly one due to drift, head/tail winds etc..  Wouldn't this apply to a box search as well?
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Jeff Victor Hayden

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• Posts: 1387
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #28 on: June 07, 2012, 01:31:08 PM »

Chris, if you have a look at Garys post #16 and the links he put in it explains what you need and, how to complete a box search pattern. A typical North/South leg would be anything from 10 to 50 Nm, depending on how lost you are Wouldn't be in the region of 350 Nm each leg, you would get lost again

IMHO
This must be the place

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Chris Johnson

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• Posts: 1069
• Trying to give a fig but would settle for \$100,000
Re: LaPook Hypothesis: Box Search around 157-337
« Reply #29 on: June 07, 2012, 01:42:04 PM »

But if you had some drift and other problems then you in theory could 'miss' the object you were looking for?

I'm no navigator, just throwing straw in the wind
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