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Old 12th Jan 2018, 09:20   #381 (permalink)
 
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The controversy over the report findings in this case are as nothing to other events in the US (and elsewhere) which were filmed and broadcast live as they happened. If people choose not to believe the evidence of their own eyes and the opinions of experts, but seek to put their own interpretation on what happened and the motivation of those involved, then the study becomes less than scientific, fake news for want of another expression.

A far easier explanation of everything that seems wrong is that the newspaper reporters at the time demanded an instant assessment at the site of the crash from anyone they could talk to. The story was published, the purient curiosity of most readers was satisfied and nobody was interested in later correcting the details because there was no longer any public interest and it had no relevance to the cause of the crash.

It is clear from the photographs that some portion of the aircraft slid along the ground after the initial impact. The final position of the tail section with the tail and rudder assembly virtually intact suggests that the sliding must have taken place while the rear fuselage was upright. The only thing that was missed is that while sliding it also rotated as would be expected with one virtually intact wing still attached. It hit the ditch and pitched over inverted. Case solved, probably.

The only requirement for this scenario to work is that the aircraft hit the ground in a vertical bank, which is supported by the available evidence and reports.

What doesn't work is a scenario that has the pilot somehow levelling the wings between striking the railroad embankment and final impact with the ground. All the documents produced to date suggest that this was the least likely sequence of events.

How the aircraft broke up is only important in establishing what components, that may have been contributory to the accident, may have been damaged or gone missing. Giving the same evidential weight to contemporary press reports against the final official report is likely to lead to conflicts in reconstructing events, as appears to have happened in this incident. The investigators were not lying, nor was there a corporate cover up, although the temptation and pressures to do so may have been enormous. Lockheed allegedly ended up losing more than 100 million dollars as a result of this and the whirl mode accidents. Public faith in the aircraft never really recovered and the age of a preferrence for pure jet travel dawned.
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Old 12th Jan 2018, 13:52   #382 (permalink)
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When it came time to write the final report, the CAB report author filled in the unimportant parts by checking to see what they'd told the newspapers, and just pasted that in? Sorry, I don't buy it.

If it rotated while sliding, then the explicit CAB statement that it slid tail first is wrong. I understand that no one wants to confront that, and perhaps if we ignore it long enough it will go away, but the puzzle remains nonetheless. Why did the CAB include extra incorrect information when they could have just ignored it? The simplest explanation, of course, is that they believed it.

The ditch had nothing to do with the plane flipping over. If the plane had stubbed on the ditch and flipped, the plane would be at least one fuselage diameter past the ditch. Instead the plane is lying across the ditch. I go into that at some length in my report. So if it was sliding forward, what flipped it?

The pilot didn't level the plane between the embankment and the next impact. Those points were 380 feet apart and the plane was moving 270 feet per second. The distance was a little over three plane lengths and under 1.5 seconds. It was all ballistics then.

I never accused the investigators of lying; I accuse them of sloppy work. They gave the clamoring reporters a first approximation that turns out to be bogus. No great surprise there. The surprise is that the investigators either held on to that bogus story, or came back to it in the course of their investigation.

Asking how a bogus scenario ended up in the official report is a legitimate question, old and thin as the evidence may be. Leaving errors in the official report is not justified by the fact that it's an aspect no one cared much about.
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Old 12th Jan 2018, 14:34   #383 (permalink)
 
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If it rotated while sliding, then the explicit CAB statement that it slid tail first is wrong. I understand that no one wants to confront that, and perhaps if we ignore it long enough it will go away, but the puzzle remains nonetheless. Why did the CAB include extra incorrect information when they could have just ignored it? The simplest explanation, of course, is that they believed it.
The CAB made no statement other than it slid rearward for some hundreds of feet, I'm not looking up the figure quoted. It matters not what the aircraft did in its slide because its not pertinent. How the aircraft came to rest inverted is not pertinent, as much as you want to make an issue of it.
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Leaving errors in the official report is not justified by the fact that it's an aspect no one cared much about
Current practise in any fatal accident is a toxicology report on the crew, whether they had ingested prescribed medication, over the counter medication, alcohol or illicit drugs, to see if they may have had an effect on the crews performance. Investigation is also made if they had adequate rest, and how much, prior to duty, and if they had any personal issues within their lives - pending divorce, death in the family, extremely sick children etc etc. This report is silent on those issues, should I allege the CAB were slack in not addressing this important issue? Sloppy work?
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Asking how a bogus scenario ended up in the official report is a legitimate question
The bogus scenario is only in your mind.
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The ditch had nothing to do with the plane flipping over. If the plane had stubbed on the ditch and flipped, the plane would be at least one fuselage diameter past the ditch. Instead the plane is lying across the ditch.
You have absolutely no idea of what caused the aircraft to invert, and the only part lying over the ditch is the very forward section of the wing box, and only just at that. The aircraft is not lying across the ditch as you are so willing to incorrectly state. You have absolutely no idea of the aircrafts gyrations from the time it hit the embankment in a near vertical angle of bank to the point at which it came to rest.

At least one fuselage diameter past the ditch? Where in the world do you come up with such ridiculous statements? You have absolutely no idea of what caused the aircraft to invert, nor how the kinetic energy was dissipated in order for the aircraft to end where it did.
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Old 12th Jan 2018, 15:50   #384 (permalink)
 
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Writing a report

The report states, (paraphrased), that the cabling from the Starboard flight station in the area of the boost quadrant “......was not recovered....”

It also infers that the aft connector “punched through” the hole, leaving shoulder marks. But the brass junction block could not fit through, therefore, the cable was not attached prior to impact.

“Not recovered”. A technical phrase, with a specific meaning. Recovery involves “locating, photography (in situ), isolating and indexing, delicate removal, carefully containing, and a chain of authority whilst in transit to a secure location.”

“Discovery”. A visual happenstance, object(s) protected, left undisturbed, pending assessment.

Was the cable run discovered, found? the language in the report does not state? “Not recovered” is unfortunate use of language exonerating liability? No. It is misleading. If “found” the obligation is to carefully and scientifically research the structure. The aft controls locker is inside the wing box, which survived the impact.

Did the team say “not found”? Need confirmation here. The cable run in question was almost certainly “located”. Did it make the trash truck before anyone granted its critical importance?

BTW. The “aft connector” is intended to pass through the hole in the spar.
It is the only way to thread the cable run into the aft controls locker from forward of the spar, during assembly of the full run.

Why? The flexible cable is permanently swaged to the sixteen foot long Lockclad cable. Lockclad will not pass easily through the hole from the aft aspect.

The “hole”:

1. Drilling through a metallic structure requires care.
2. After through and through penetration, the hole must be “eased” at both faces, to prevent the establishment and propagation of cracks in the spar. It is likely (hopefully) this was accomplished by “rounding” (or at least “chamfering”) each perimeter to forestall later cracks from forming.

This “easing” could easily be mistaken for remnants of a violent pass by the connector.

I maintain: The kit between the Boost quadrant and the slack absorber was stripped away from the quadrant during the first (fuselage) impact. Both Port and Starboard runs. Both terminal installations remained in the control bay.

I am going to further say, subject to further examination, that the cable forward of the slack absorber was connected in flight, and stripped away whilst attached upon impact.

With the number of aileron squawks, and their diversity, I would question whether replacement of the boost unit would have mitigated all of them?

By boost unit, do we mean the cylinder and drive arm only? Do we include the pumps, their power source, and the control valve?

What about the ”taper pin”, and the faulty “indicator light”?

Maybe in FOIA.

Last edited by Concours77; 12th Jan 2018 at 16:37.
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Old 12th Jan 2018, 16:02   #385 (permalink)
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The CAB made no statement other than it slid rearward for some hundreds of feet, I'm not looking up the figure quoted. It matters not what the aircraft did in its slide because its not pertinent. How the aircraft came to rest inverted is not pertinent, as much as you want to make an issue of it.
We went over this in excruciating detail a couple weeks ago. Wreckage was spread for a length of 1200 feet from the embankment to the final mass. From the 380 foot point the plane slid (per the CAB) tail first another 820 feet. Do the math.

This is an untrue statement. It's not a lie, it's an error. It's easy to show the report is wrong, but it's hard to tell what happened. Hence the puzzle.

Quote:
Current practise in any fatal accident is a toxicology report on the crew, whether they had ingested prescribed medication, over the counter medication, alcohol or illicit drugs, to see if they may have had an effect on the crews performance. Investigation is also made if they had adequate rest, and how much, prior to duty, and if they had any personal issues within their lives - pending divorce, death in the family, extremely sick children etc etc. This report is silent on those issues, should I allege the CAB were slack in not addressing this important issue? Sloppy work?
No, I'm fine with them not reporting that. However, if they had reported that a crew member was getting divorced and it turns out the crew member was never married, I'd call that sloppy. The issue here is not that some detail was omitted but that an error was allowed to remain.

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You have absolutely no idea of what caused the aircraft to invert, and the only part lying over the ditch is the very forward section of the wing box, and only just at that. The aircraft is not lying across the ditch as you are so willing to incorrectly state.
The aircraft is covering the ditch; it is lying across it. It doesn't cover the entire ditch because the ditch is wider than the plane. But it covers part of the ditch, so it is lying across it. If say you're lying across a seam in the carpet, that doesn't mean your belt buckle must be in contact with the seam to make the statement true. For one who was pretty emphatic about my inability to comprehend, you're not showing yourself to advantage here.

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You have absolutely no idea of the aircrafts gyrations from the time it hit the embankment ... to the point at which it came to rest.
Well, a pretty sketchy idea at best. That's what I'm working on. I bring my thoughts here so people can critique. Concours77 pointed out my error on the ditch, for example, for which I'm grateful.

Quote:
At least one fuselage diameter past the ditch? Where in the world do you come up with such ridiculous statements? You have absolutely no idea of what caused the aircraft to invert, nor how the kinetic energy was dissipated in order for the aircraft to end where it did.
It's in my document. If the plane stubbed against the ditch and flipped forward, it could have done it a couple ways. Test it with a box of kleenex on a desk. It might hit, rotate about the point where it hit, gone vertical, tipped over and landed on its back. The box of kleenex will be one box-height from the stubbing point.

For the plane to land on top of the ditch when it flipped, it must have bounced at least one fuselage-height into the air while pitching forward. This is a relatively high-energy arrival, not a sliding stop. I can't quantify it for you, but you're bright enough to envision what I'm saying. So if the ditch played a role, then it didn't hit the ditch and tip forward, it hit the ditch and bounced into the air at least 13 feet.
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Old 12th Jan 2018, 16:03   #386 (permalink)
 
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My postulate is that the tail section and wing, attached and sliding (upright) landing gear forward, dropped into the ditch, snagged, and the assembly “pitch poled” to land as found.

This demands that it was the last of the energy contained in the structure(s) that did the work. From the condition of the tail, any inverted slide would almost assuredly have destroyed the VS, HS, and rudder. This is plausible and demonstrable, hence probable.

G0ULI:

“How the aircraft broke up is only important in establishing what components, that may have been contributory to the accident, may have been damaged or gone missing. Giving the same evidential weight to contemporary press reports against the final official report is likely to lead to conflicts in reconstructing events, as appears to have happened in this incident. The investigators were not lying, nor was there a corporate cover up, although the temptation and pressures to do so may have been enormous. Lockheed allegedly ended up losing more than 100 million dollars as a result of this and the whirl mode accidents. Public faith in the aircraft never really recovered and the age of a preferrence for pure jet travel dawned.”

I have intimated something (post 384, above) that puts the report’s accuracy and integrity in doubt. That is intended. Would you consider a very careful and discerning discussion about what Lockheed and the CAB decided to report in this accident?

Last edited by Concours77; 12th Jan 2018 at 16:40.
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Old 13th Jan 2018, 03:17   #387 (permalink)
 
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It doesn't cover the entire ditch because the ditch is wider than the plane
You make much of the meaning of words, what they say or imply. The ditch is not wider than the plane, it is longer. Its width is a matter of a few feet, length in the order of 100+ feet. Had the CAB made that statement I can only imagine the ridicule.

Your,
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This is an untrue statement. It's not a lie, it's an error. It's easy to show the report is wrong
would apply presumably?
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Old 13th Jan 2018, 03:30   #388 (permalink)
 
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Concours77

If we are to question the meaning of given words in the official report, reference should be made to the definitions contained in dictionaries that were contemporaneous or previous to the event and not to modern reference sources.

The archaic language used and retained in the British legal system hinges around the fact that the phrases used have a very distinct definition as established by prior court judgements.

I maintain that certain disputed parts of the official report are not deliberately inaccurate or even incomplete accounts of events. I suggest that in the light of more modern reporting standards, it is we who are drawing incorrect interpretations of what was said and meant at the time. Also we have to account for less advanced analysis techniques and methods available 55 years ago. That predates colour TV and most people having a landline phone in their home as far as the UK is concerned. Yet here I sit typing on a tablet with access to all the knowledge in the world just a few screen taps away. Okay not quite, but you get the idea.

I have absolutely no doubt that Lockheed would have dearly loved to write the accident off to pilot error. There are certain parts of the report that lead me to think the investigation was initially biased towards establishing this as a cause. That would not be considered unreasonable at the time because the majority of air accidents then were frequently down to pilot error. The increasing complexity of aircraft, lack of CRM, failure to recognise performance or weather limitations, were all contributory factors, but the pilots were frequently and unfairly given the blame in many case, in the light of more modern understanding of the issues.

Every aircraft has design flaws inherent in its construction. To my mind, the side stick controls in modern Airbus aircraft have directly contributed to quite a few accidents and near misses. Many professional pilots would vehermently disagree with my opinion and counter argue that the system is vastly superior to the older yoke design.

When I was taught to fly, the rule was to avoid thunderstorms by a minimum of ten miles. Modern aircraft with a schedule to keep are flown over, under, or through thunderstorms every single day, mostly without incident. But who or what gets the blame when things inevitably go wrong once in a while? Mostly, the pilot!

I am quite happy to accept that your version of events may lean towards being a more correct account considering the political, commercial and sociological pressures to try and play down aviation accidents at the time. I question what purpose is served in picking at these threads in the hope of unearthing some official wrongdoing though. All the people involved are undoubtably deceased and the fact is that in the light of this and other early accidents, the Electra and variants such as the Orion P3, has had a long and distinguished career as one of the most robust aircraft ever built.

I sincerely hope that the FOI request turns up more complete records of the investigation such as original notes and witness statements together with the investigators notes. Only with access to these records can any serious and legitimate attempt be made at rewriting the story of flight 706.

These records should be stored in an archive somewhere, although if they have been destroyed or disposed of and that may be considered as going some way towards pointing at a cover up or somewhat misleading account of the investigation. Of course, the documents could have been innocently destroyed by fire or other natural events, become lost in administrative clutter, eaten by vermin, or simply disposed of because there was no room to store them.

I personally don't see any evidence of conspiracy or skullduggery in the official account. There are gaps which can be filled by inference, but I doubt that these were purposefully designed to mislead in any way. I fully accept that documents could emerge that cast doubt on the official report, but until they surface I have to regard further discussion as being likely to be fruitless.
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Old 13th Jan 2018, 03:44   #389 (permalink)
 
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Amen G0ULI.
Quote:
I have absolutely no doubt that Lockheed would have dearly loved to write the accident off to pilot error
The report clearly shows that the direct cause of the accident was sloppy maintenance, little different to the DC-10 engine fell off case at O'Hare. Lockheed was in the clear. As an accident cause (maintenance error), the files are replete with examples.
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Old 13th Jan 2018, 15:09   #390 (permalink)
 
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“All the people involved are undoubtably deceased and the fact is that in the light of this and other early accidents, the Electra and variants such as the Orion P3, has had a long and distinguished career as one of the most robust aircraft ever built. “

Uh oh...

My research shows one Alan S. Boyd alive and living in Florida.

He was Chairman of the Civil Aeronautics Board during this accident investigation.

His signature appears at the top of the signature page I posted recently.

His Wiki CV reports his career summed up by this title......politician.
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Old 13th Jan 2018, 15:12   #391 (permalink)
 
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Amen G0ULI.The report clearly shows that the direct cause of the accident was sloppy maintenance, little different to the DC-10 engine fell off case at O'Hare. Lockheed was in the clear. As an accident cause (maintenance error), the files are replete with examples.
In the Law, the “direct cause” is reasonably easy to understand. Also in the Law is something a bit more difficult: The procuring cause.

Camel, straw? The direct cause is the last straw. The procuring cause is the mass of straw already borne by the poor animal’s back.....

megan, here, we are in agreement.

G0ULI

I maintain that certain disputed parts of the official report are not deliberately inaccurate or even incomplete accounts of events.

In the day, the public slavishly obeyed authority, and virtually always accepted official data as gospel. Given that power, there existed a freedom to exaggerate, embellish, ignore, and even lie on the part of a government charged with our “best interests”. This was not done necessarily for cynical reasons, but more for reasons of “protecting” the public. “Well flight crew are deceased, no good can come of chasing a different theory and hobbling an otherwise exemplary corporation with further “trouble”. “

Lockheed had contracts with the Government, and patriotism compelled a certain kind of “pass” for those boffins who almost never make fatal mistakes?

A trusting public, mostly those who accept “official probable cause” as certainty, not to be doubted....?

“Probable”. A delightful word that lets the potential culprit off the hook, and seemingly immune to a different view?

Now we can discuss some design issues that hobbled the poor Electra? A tease?

Why did Lockheed perform inspections and develop a defense of the wing area adjacent the aileron/flap? megan’s previous analysis I believe not to be accurate. “Airloads”?......please.

I think the pilots figured out what was happening. Too low, and no time to broadcast what they knew?

Oh, those pesky “chattering” ailerons? “Only in flight”? How did the aircraft “fly” four hundred feet further than contact by the wing tip at the tracks? At ninety degrees Bank? They were higher than wing tip proximity would define? So, with that, here is:

G0ULI: The only requirement for this scenario to work is that the aircraft hit the ground in a vertical bank, which is supported by the available evidence and reports.

YES! At ninety degrees Bank, the aircraft is not flying, it is falling, like a brick, at one G. Yet it stays aloft another four hundred feet? It is accelerating in the vertical at 16feet/second/second. It should have impacted the ground (a second time) no further than one hundred feet along. Probably more like fifty. Another way to envision this? When the wingtip struck, the altitude of the aircraft was already in the minus. By twenty feet...

Levitation?

A reduction in power as “routine”? Just after breaking ground? At liftoff at four thousand feet down the runway, they flew another four thousand feet and managed to climb only one hundred feet? That’s a climb at two degrees. At one hundred feet the aircraft commenced a roll moment to the right? Notice that the report does not say: “Pilot commanded right turn?”

I have been reluctant to start this, pilot error is imposing, but I believe the pilots had no part in this accident. Similar to the DC10, the pilot’s were along as pax.

Last edited by Concours77; 13th Jan 2018 at 18:54.
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Old 13th Jan 2018, 19:06   #392 (permalink)
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The ditch is not wider than the plane, it is longer. Its width is a matter of a few feet, length in the order of 100+ feet.
See Megan, that's why your contributions are important to me. When I propose an idea, I can always depend on you coming to the table with the strongest argument you can muster. Apparently that was it.
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Old 13th Jan 2018, 19:22   #393 (permalink)
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At liftoff at four thousand feet down the runway, they flew another four thousand feet and managed to climb only one hundred feet? That’s a climb at two degrees.
In 1961 the control tower was 100 feet tall. The most respected witnesses would have been the tower staff, and they could use the horizon line to judge the height of the plane. So this is likely to be a relatively accurate number.
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Old 13th Jan 2018, 19:53   #394 (permalink)
 
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In 1961 the control tower was 100 feet tall. The most respected witnesses would have been the tower staff, and they could use the horizon line to judge the height of the plane. So this is likely to be a relatively accurate number.
Thanks, your work is impeccable.

The problem started at run up, and was underway as they rolled onto the runway without stopping, cleared for an immediate departure.

They should have been at five hundred before turning but already the performance and airworthiness were deeply degraded, all the a/c could do was an anemic climb, and start an uncommanded turn, right.

Everything I propose, and the destination I have, is taken from the report itself.

Take it apart, challenge it, it would be welcome.
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Old 14th Jan 2018, 01:00   #395 (permalink)
 
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See Megan, that's why your contributions are important to me. When I propose an idea, I can always depend on you coming to the table with the strongest argument you can muster. Apparently that was it.
Glad to have been of help. Nevertheless, what I said is true, had it been a statement made by the CAB you would be all over it complaining about their lack of exactitude, and written a hundred page dossier on why they got it wrong.

You are making much of the CAB simple sliding statement, overly much I should say, and what you've put forward doesn't stand, for the simple reason no one here knows what manoeuvres the aircraft went through to reach its final location. It's all guestamology (new word). We can all come up with plausible, in our own mind, theories. Personally, I can see how the aircraft could plausibility have slid backwards to almost its resting place, but it's not provable from the evidence to hand (photographs), and I'm not about to engage in debating theories.

I use hard facts, such as the embankment scar that proves beyond doubt the aircraft was in a near vertical bank. What happened between that point and the resting place is all guestamology to anyone who has not had the benefit of surveying the wreckage distribution and ground scars. Get map of the wreckage distribution and you are a long way forward to actually understanding how events played out. They would also have made a map of ground scars, perhaps superimposed on the wreckage distribution. Get those and you have it wrapped up, until then any theories proposed are pie in the sky.
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His Wiki CV reports his career summed up by this title......politician
There are always political appointees on the board.
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Old 14th Jan 2018, 01:00   #396 (permalink)
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The problem started at run up, and was underway as they rolled onto the runway without stopping, cleared for an immediate departure.
Their haste may have contributed to the problem. If they had to wait a bit for clearance they might have noticed an issue. If already rolling and the issue wasn't waving a red flag in their face, they might not have addressed it as carefully as they should.

The reason for the "toll road" departure was that it shortcut an extra hand-off, so this might have been part of the mindset. At any rate, that put them in a turn at very low altitude, problem or not.
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Old 14th Jan 2018, 02:23   #397 (permalink)
 
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Their haste may have contributed to the problem
If that was considered to have been an issue, all the more reason for an investigation into the crew's life/background/toxicology. I'm sure haste is not the case, I don't know the crews practise of course, but most pilots upon line up check the killer items which pertain to aircraft type - fuel on, flaps set, controls free being but examples. But of course you can't tell.
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Old 14th Jan 2018, 03:33   #398 (permalink)
 
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Concours77

You may wish to revisit your figures.

The acceleration of an object in free fall under Earth's gravity is 32 feet per second, per second, or approximately 9.81 metres per second per second. I will stick with imperial units here.

The wingspan of the Electra is 99 feet, putting the centre line of the aircraft 49 feet 6 inches from the wing tip.

The top of the embankment is recorded as being 25 feet above the surrounding land. The power lines would be raised above the embankment by some arbitary figure to prevent electrocultion risk to passers by.

If the aircraft wing hit the embankment at an angle of between 60 and 70 degrees, even hitting the base of the embankment would place the fuselage centre line a minimum of 30 feet above the top of the embankment. The propellor strike marks indicate that the wingtip struck the embankment significantly higher up, no more than half way. So no more than 12 feet of the wingtip was likely to have made contact. This places the centre line of the fuselage roughly 42 feet above the top embankment and therefore 77 feet above the surrounding lower ground.

The aircraft travelled 380 feet before making the first solid impact with the ground. Allowing for the descent to be in free fall, the time taken to hit the ground would be roughly 1-1/2 seconds.

380 feet travelled in 1-1/2 seconds equates to a speed of 173 mph, or around 160 knots. Exactly what we would expect to see in a take off and climb flight profile. These are the minimum speeds needed to achieve the observed results. The true speed could perhaps have been 20 mph (17 knots) higher. Any extra speed and/or air resistance opposing a free fall drop would allow for the known 5° to 10° nose downward flight path while still allowing 380 feet of flight beyond the embankment.

Naturally these figures are back of an envelope calculations, but close enough to agree with the known aircraft performance figures, the figures given in the report, and to substantiate claims that the aircraft could and did strike the ground with a wings vertical bank angle.

[I have assumed the width of the fuselage to be 10 feet to simplify my calculations.]

I don't just compose these posts without considering the maths involved. On the other hand I really can't be bothered working through all the trigonometry to give a range of figures to satisfy every possible answer to the nearest inch for every possible bank angle and velocity.

There can be absolutely no doubt that the aircraft crossed the embankment at an angle of 60° to 70° with the right wing tip making contact with the embankment. The main impact with the ground occured with the right wing aligned between 90° and 100° vertically aligned to the ground, exactly as the investigators of the time stated. What happened after that is conjecture and guesswork.

The laws of physics don't lie.

Last edited by G0ULI; 14th Jan 2018 at 05:13.
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Old 14th Jan 2018, 17:06   #399 (permalink)
 
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G0ULI,

Here:

The aircraft travelled 380 feet before making the first solid impact with the ground. Allowing for the descent to be in free fall, the time taken to hit the ground would be roughly 1-1/2 seconds.

Uh oh... you assume no vertical velocity at RR embankment? I give the vertical vector a value of 2000 fpm. At Impact.

The angle of Bank and the lack of lift did not begin at RR impact.

You assume no vertical velocity at the tracks? The a/c also accelerated radially, turning the left wingtip toward Earth at close to the aircraft’s horizontal speed, which negates your fuselage centerline as reference. The fuselage did the same. It’s ASPECT relative to the Earth changed, downward, with a component of what had been forward velocity. IOW, its flight path was altered, dramatically, and that changes your very basic calculation? It didn’t continue along pointed where it had been.

Falling at one hundred forty feet per second, the Electra should have hit the ground in one half second. Not counting for the added acceleration to which you refer?

That is approximately one hundred feet beyond the impact with the tracks....
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Old 14th Jan 2018, 17:24   #400 (permalink)
 
Join Date: Nov 2016
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BRDubois

Their haste may have contributed to the problem. If they had to wait a bit for clearance they might have noticed an issue. If already rolling and the issue wasn't waving a red flag in their face, they might not have addressed it as carefully as they should.

The Electra’s ailerons “droop” at less than flying speed, it isn’t until they gain authority from airflow that they nest to fair in chord. They are sloppy on the roll.

Turning (nose wheel, Rudder) and lining to centerline from a rolling entry takes skill and may cause a bit of distraction.

I think they may not have noticed aileron issues until the ailerons “came alive” and their flat climb may actually indicate that they considered an abort. Once the roll issues presented as critical, they were past the opportunity to land. Pilot would have known Roll was creepy almost instantly. I think the Roll right was uncommanded, and was not part of the aileron issue blamed for this crash.

Lockheed designed an experiment to test airflow at the aileron/flap merge. They removed the flap outboard jackscrew before measuring various airflows. Any idea why? I have a theory.
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