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Friday, June 3. 2011
I'm an airline disaster buff.
They're the ultimate Sherlock Holmes mysteries. You're given mere scraps of information, the wreckage is usually twisted beyond recognition, and you're faced with the knowledge that nine times out of ten you're looking for a chain of failures, not just a single part that suddenly went kaflooey.
And unless it's an actual bomb, which is fairly easy to detect afterward because of the micro-pitting that takes place during an explosion, the one thing that modern airliners almost never, ever, do is suddenly just go poof and drop off the radar screen without a peep from the crew.
As Air France Flight 447 did two years ago, taking 228 people to a watery grave.
When it comes to gripping suspense, my favorite airline disaster show is here. But when it comes to pure sleuthing with almost nothing to go on, I thought the show on Flight 447 was tops. Back at Air France headquarters that fateful night they received a small, routine databurst of info from the plane's computer in the final minutes, and then...
It appears they nailed everything except answering the one, big remaining question; why did it crash merely because the automatic systems had shut down? In the show, they posited a plausible theory, but they were working on the assumption that the pilots had reacted as they had been trained to do.
Such, however, doesn't appear to be the case.
That's really stunning, in that a climb of 35 degrees in an jetliner would feel like you're almost going straight up. How all three pilots could collectively ignore a lesson that's taught from day one in flight school is beyond comprehension.
On the other hand, as the article notes:
So further examination of the black boxes might yield an answer, but everything I've read indicates that the only parts to actually fail were the ice-clogged air speed indicators, and while that inaction shut down the autopilot and associated systems, everything else on the plane (attitude controls, engines, etc) functioned normally.
Best guess is that, while the corporate execs won't actually face the guillotine (probably), the courts will still find it to be the airline company's fault. In general, because this is a socialist nation where the worker bees (the airline pilots union) must be protected at all costs, and specifically because it's always easier to blame the greedy, filthy-rich corporations than it is to acknowledge human fallibility.
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Interesting site & comments on 447.
"Thinking about that gives me the creepy-crawlies."
I'll say. I also agree with this:
"I am not buying into the theory that the two co-pilots did not know what they were doing. Air France pilots are some of the best on the planet."
Air France has had its share of disasters (the SST, a couple of A320's), but the pilots are always lauded for doing everything they could. In thinking about all the air disaster shows I've seen, it doesn't strike me that any one country stands out. If it tends to lean toward poorer countries, that's usually an equipment failure or lack of upgrade in the tower (like doplar radar), rather than the pilots doing something goofy. All in all, it seems like half the time it's a part failure of some type, with the other half left up to chance.
I did not know that the black boxes at the Twin Towers were never found. The debris at that site was sifted through with a fine tooth comb looking for human remains.
Something must be amiss.
I would have been surprised if they did find the black boxes after those crashes and tower collapse. There wasn't much left of anything when all was said and done.
I didn't spend long on the hunt, but the issue appears a bit confusing. At one point, the officials said they didn't find any of the boxes. Another report says they found them, but they were too damaged. Then at some point they apparently issued some flight data from one of the data recorders, but I didn't pursue it because the issue is moot. They found the black boxes in every single disaster flick I've seen (now counting Flight 477), so obviously it's not a problem.
A debatable question, an issue open to argument; also, an irrelevant question, a matter of no importance.'
I, too, have heard both responses as to whether the "black boxes were found or not. The issue is certainly confusing. But how would one clear up the confusion? I recently saw a taped interview, with an individual, with an arms-length connection to that issue, who indicated his knowledge that 3 of 4 had been recovered (History Channel or Discovery; I can't recall).
I don't believe that fact, if true, would ever be officially released. The CVR's could/would be very revealing.
IMO, if they have been found, they will never see the light of day.
Garnook of the Northern Hinterland -
"also, an irrelevant question, a matter of no importance."
Saying a "question" can be a "point" is oxymoronic. You need a new dictionary.
"IMO, if they have been found, they will never see the light of day."
I can't see why you'd say that. Except to the Truthers, there's certainly wasn't anything to "cover up". Just another day behind the wheel until the bad guys showed up.
It might also be pointed out that there's a big dif between "finding" the boxes -- and actually being able to read the data. I saw a disaster show just last night and when they opened the recorders, nothing but ashes fell out. And since the fires that consumed the Twin Towers got hot enough to melt steel (source: Rosie O'Donnell), it wouldn't be much of a leap to assume the four recorders were toast. Literally.
Sorry, I forgot to check with "Rosie". Always good to go to the source of knowledge. How is she hangin' these days? Burning my dictionary as we 'speak' !
Actually, Rosie and I go back a ways. I think so much of her that I actually started off this whole page with her name in the spotlight. Hard to garner a higher accolade than that.
On the other hand...
Well, I can think of a couple of scenarios - speaking strictly as a private pilot, fixed and rotary wing - I'm not a professional aviator.
The first is panic. The instruments are telling you one thing, your instincts are telling you something different. These are super automated cockpits and pilots, while well trained and professional, tend to rely more on them than what their own lying eyes and ears are telling them. If they were flying through a cloud deck, they may have become disoriented - that happened to me once, fortunately I broke out of the cloud deck and managed to properly reorient to the horizon.
Second, and this is what I think happened, is they entered into a stall condition and COULDN'T break out of it because of downdraft or Clear Air Turbulence. That can happen in cloud decks or clear air if they were flying anywhere from 25 to 39,000 feet - the cause of the clear air weirdness isn't totally understood, but the principle cause is two different areas of air moving at different speeds which can create turbulence or downdrafts. If you've lost total forward momentum, but you think you are moving forward - well, catastrophes can happen. Jet streams and their movement and change in altitude can also create issues.
Not to brag, but I spent some time in an actual 747 simulator once as an observer and ran through a bunch of different scenarios watching the professional pilots do their thing. I can tell you they were baffled once - they finally got it figured out but it was a close thing. :>)
The problem with your first scenario is that you somewhat countermanded yourself. You state correctly that they're trained to ignore outside incidences when the instruments differ, then you state they might have become disoriented by a storm. As it turns out, they might have been fooled by a smaller storm that was just in front of a real bruiser, but still nothing that would bring down an airliner.
The problem with the Clear Air Turbulence scenario is, as you said, that it still left them 25K feet to get the plane under control, plus they're travelling forward at a pretty brisk clip, so eventually they should have pulled out of it.
Being in a 747 flight simulator must have been awesome. The fire that breaks out on board. The sudden decompression. The screams of the dying and wounded. The brave actions of the captain as he fights to keep his bird from certain death.
"they finally got it figured out but it was a close thing."
And you thought to yourself, "Damn! There's goes the idea for my next novel, 'Death In The Skies'!"
They're getting conflicting data, have no airspeed reading, and may be not be trusting the stall warning either.
Incidentally there's one circumstance where you raise the nose for a stall, namely a tailplane stall (from icing); and unfortunately the symptoms of a wing stall and a tailplane stall are not easy to distinguish.
Seems, to me, that they forgot the most basic of unusual attitude recovery. First, follow the VSI. Find out where the fuck your nose is in relation to the horizion. Level it.
Second, where are your wings in relation to that same horizion. Level them.
Then, once you are flying straight and level, figure out what the fuck is wrong.
Airspeed is, I would contend, the biggest sucker punch in the cockpit.
The clip's theory sounds good, namely that they didn't add power automatically taken off by the fly by wire system and so were always at the wrong speed to fly under no airspeed indicator conditions at any angle of attack. (Trapped between a gravity stall and a shockwave stall.)
The lesson would be to remember to scan the actual power in use readout; the levers can lie.
"Some wonder if cockpits are being over-computerised leaving pilots baffled when it comes to manual flight in an emergency."
I wouldn't be surprised if the crew could not control the aircraft.
It's so automated the crew needs to perform rather tricky feats to get the computers to relinquish control at all, actions that I'd not be surprised if they weren't taught in familiarisation courses and/or prohibited by company procedures (if not actively made impossible by airlines).
The first A320 series aircraft (of which the 330 is a development) could not be controlled manually at all. It was only after 2 crashes that these overrides were grudgingly implemented by Airbus, who considered their computers to be infallible.
Page 30 of IFACTA's "The Controller" publication (Vol 34 1995) yields this interesting nugget:
Airbus Training: Airbus had difficulties recruiting the correct pilots for its A320/330/340 series. They approached a specialized firm in psychological recruitment and this firm produced the following criteria: To be an excellent Airbus pilot, the candidate must possess the following qualities:
1/ To be able to complete "Super Mario 3" in less than 1
2/ To be able to type at least 80 wpm,
3/ Not to possess a driving licence.
The Airbus directors looked at the result and said: "We can understand the first two but why should pilots not have their driving licence?"
"Well," replied the consultant, "the pilots who already have their driving licence may have to much analogue experience, and cockpit training wil be negatively influenced by this."
While my 30 years in the business was from the ATC end of the microphone, I watched the digital revolution start to push the analogue world aside, both in aircraft and ATC equipment.
A great read, for those so inclined, is "Human Factors In Air Traffic Control" by V. David Hopkin. One can easliy see comparisons that could also apply to the pilot end of the equation. I wonder if a similar book has been written, from the pilot's perspective, as to the negative effect computers have had in the cockpit environment.
I've known many senior pilots, in my time and some who did not want to fly the Airbus (and similar computer created cockpits) because as they put it: "I want to fly the airplane not fly the computer". It was a trust issue. Some refused upgrade promotions to stay in what they termed "the real world of flying".
Eventually the accident report will be released and the Pitot-Static Tube, I believe, will be identified as having played an integral role in the accident. Airbus was aware of the "Pitot Problem" but had not modified this particular aircraft.
And I also hope that the authors of said report will have the fortitude to deal with the "Human/Computer Interface" issues that plagued AF447 and will continue to plague the world of aviation.
It's not like they were in an unusual attitude. They were in an unknown predicament, and the book response wasn't working (85% power and 5% pitch (=aoa?)), owing to not being at 85% power because of a misleading fly-by-wire treatment of throttle levers.
If they hit the water flat, the plane was under control but not responding to what they thought ought to fix it.
I'd imagine a turn and bank recovery wouldn't need much refreshing - stop the turn with the rudder, then center the ball with the ailerons, then fix the speed with the elevators (except they don't know the speed, which is the condition they crashed in).
If Airbus wanted to program up an interesting independent backup for airspeed, they could synthesize it from GPS readings.
A Kalman filter (which they undoubtedly use all over the place) could keep it calibrated to the current winds, even just using aircraft response.
It does raise the question why, if the book response (85% power and 5 degrees pitch) works, why the autopilot doesn't default to that instead of handing the mess over to the pilots unassisted.
Or at least have a try-the-book-response button.
"If the depths and ocean water are a problem, use a VLF signal like submarines do"
Generating and transmitting VLF signals requires massive transmitters and antennas. The transmitters require megawatts of electric power and VLF signals can't penetrate thousands of feet of water. The Germans developed VLF transmitters for communicating with their U boats and after the war we couldn't figure out at first why anybody would build a radio transmitter brodcasting on 15kHz. The reason was the U boat didn't have to surface to receive the signal.
Ray - While sub VLF systems require, as you said, massive amounts of power, they're trying to reach the nearest receiving station, which might be thousands of miles away. You'd think for just three miles, they'd be able to whip out a mini version of VLF or ELF, since whatever they're using now clearly isn't working.
For that matter, in thinking about it, I don't recall one disaster show where they used the beacon to locate the boxes. On land, they're usually just part of the rubble, and when they're lost at sea, as in the case of 447, it's usually a case of perseverance and blind luck that turns them up because the batteries have long futzed out. It just seems odd that we can talk to an astronaut on the moon in real-time, but we can't develop a box with a beep that can be heard through water?
I wonder why you are saying this is a mystery which possibly will never be solved and that you have seen nothing that indicates Aircraft failure except the Pitot's
Fact is: My friend, you have seen nearly NOTHING and the little disclosed is probably not the truth in several aspects.
And of course: much what you call a mystery would be solved if BEA would cease to HIDE the sound tracks in the cockpit, simple listening to what the pilots said and commented during the long minutes previous to the crash.
Factually, there are many reasons to believe that we are in front of a cover up, as what was written by BEA does not explain between other:
1) Why the pilots suddenly forgot their stall-related elemental training
2) why the communications with the Aircraft suddenly were interrupted when the autopilot disengaged
3) Why the last the communication transmitted to the exterior indicated multiple failures in the aircraft
4) Why the vertical stabilizer broke away and was found 30 miles from the other debris
5) Why BEA speaks of a super-storm when the bulk of it was circumvented
6) And last but certainly not least, why, the first thing they released were blame against the pilots but refusing to support is with the complete transcript in the cockpit
So, why I should not think that the self-investigating French have not taken the cue form FUKUSHIMA, Tokyo Electric and the Japanese Government, feeding for month false information to the world until they had to admit it!
Factually, I do not even believe that the PITOTS have much to do with this accident, this non reliable instrument was a good diversion to hide the truth!!
Here is something you may be interested in:
Airbus has a history of problems with composite materials used in critical areas of their aircraft, specifically the rudder.
As to your suggestion of a coverup? Always possible. Don't forget that the Airbus consortium was created to compete with the former "Big 3" of US manufacturers. I would think the company and the country (France) would do their best to prevent design problems (and they are there) from killing their 'golden goose'.
* "...., specifically the vertical stabilizer (which includes the rudder).
Are you suggesting that the vertical stabilizer break away was the CAUSE of the accident??
this would explain a lot of things, as
- that it was found 30 miles from the other flotsam
- that it caused a multi tude of short circuits, which caused
first the emision of a lot of mafunction signasl and
immediately after the interruption of the communications
- As you read in my post, I didn't believe that the Pitots were the initiators of the accident, but a convenient argument for the cover up.
- and of cause, the pilots would have commented this "minor" issue and therefore BEA surpressed any mention of the interchanges in the cockpit!!
- I cannot judge this: could this be the reason that the
pilots were not able to put the nose of the aircraft dowm??
PLEASE LET ME KNOW. Thanks in advance
"Are you suggesting that the vertical stabilizer break away was the CAUSE of the accident?? "
I'm not qualified to make that suggestion but the A300 series has a recorded history of problems with the empennage and it's composite components (see link above). And Airbus KNOWS of these problems.
I have read many accident reports in my time and I shall have to await the 'official' report, on AF447, before I can evaluate what is written. What I do know is how and why these reports are worded as they are.
I still think that the pitot-static system plays a role in this accident (gut sense). But there is something more to the whole issue. The sad thing is, that with all this modern technology, its nerve centre relies on the most basic analog device, a hollow metal tube, to provide the parameter that the whole flight system requires to function properly.
In the end, no matter what the determination of cause, the Human Factors issue, IMO, will be given lip service. It most likely will be "pilot error" not a system design error. The reality is that the FMS functioned as it was designed to function. And THAT is the problem and its "Achilles' Heel".
Deep Stall at Neptunus Lex is a good post + comments to read on the crash.
This link was in the comments Midnight Meditations at Flight Level 390.
Which has this link in those comments AF447 Wreckage Found
Covering a couple of points raised in the original article. The flight recorder showed that the elevator trim of AF4476 was set at 13 degrees nose-up. With that setting it was apparently impossible for the pilots to get the plane's nose down and out of stall using just the control sticks. Air France pilot training for a stall does not include checking the elevator trim setting. The pilots had three minutes of high speed descent to figure this out on their own.
The problem with finding the flight recorder in water is due to the nature of sound transmission through water. A submariner would be the best to explain this, but varying salinity, thermoclines, and convergence zones are all part of the problem. Sound moves through water in very strange ways, when it's transmitted at all.
Dear Looking Glass. As I am not a piliot, bay a mere Elecromechanical Engineer (even with 50 year experience) I am not sure if your post is a answer to my question
""- I cannot judge this (I refer here to the vertical Stabilizer break off) : could this be the reason that the
pilots were not able to put the nose of the aircraft dowm??""
Thanks in advance for your eply
Two quick points:
- If the stabilizer broke off, the plane wouldn't be able to go up -- like it did. Plus, and I'm no engineer so I might be wrong on this, but my guess is that if the stablizer broke off, the flight data recorder might notice it in passing.
- As for the 'cover-up' theories, be serious. It has the same fatal flaw the 9/11 Truthers had: if would be flat-out impossible for all of the people who are involved to keep their mouths shut. In the YouTube age where everybody want to be a star? Some lab technician would tell his wife, who'd tell her big-on-Facebook girl friend, and that'd be that. Yet, to this day, not one rumor has surfaced.
No pun intended.
"If the stabilizer broke off, the plane wouldn't be able to go up -- like it did. Plus, and I'm no engineer so I might be wrong on this, but my guess is that if the stablizer broke off, the flight data recorder might notice it in passing."
If only the vertical stabilizer broke off, but not the horizontal stabliizers and elevators (as in the Aug 12, 1985 JAL123 crash), pitch-up/down would be possible. And the data recorder would indicate this, I believe. Have you read any "black box" transcripts yet? I haven't as I don't think they've been released.
As for the possible 'cover-up' issue: it would only be such IF data information contained on the flight recorders was intentionally left out of the final public document. But we would never know, would we?
I hope you read my link above. Some good information there.
Here it is again: http://airbusvertstabs.blogspot.com/
While there is a hostory of problems, it is still speculation, at this point as to what actually happened with the airframe and whether the interface of human/computer has reared its ugly head again. Time will tell. I'll wait 'til get a copy of the final conclusions and read from there.
Yes, lets be serious: Conspiracy theories as for 9/11 and the moon landing had no other support as the sick mind of the doubters.
But... Here, you have a wealth of supports, the main being
absurd accusations against (dead) pilots, but refusing to release, even mention, what these pilots spoke during the fatal last minutes (other tan some innocuous, unrealistically laconic statements)
Vertical stabilizer found 30 miles from the flotsam
an accumulation of alarm signal released just before the communications to the outside world were interrupted, when until this moment all was normal (meaning well before the downfall)l
a investigation conducted without any insight by non-biased persons of a gigantic French dominated company by a French Institution, where clearly the national interest of France would be very affected, should Airbus be found guilty, a company where the German component (Daimler) is looking desperately for a way out, for not clearly disclosed reasons.
1) So, my friend, do not discard by comparing me with the 9/11 nuts and understand that because such nuts exist, conspiracy nevertheless exist too!
Have you followed what happens in FUKUSHIMA, where a Japanese Mega-company with the support of the Japanese Government tries to mislead and lied for months to their people and the whole world??
This happens when too much money and prestige are in play (and where the Media is patriotic enough by not to be too inquisitive (contrary as in the US)
2) You write "Yet, to this day, not one rumor has surfaced"
Sorry, I would say, hundreds. Beginning with the German Magazine DER SPIEGEL (which nevertheless, being a worldwide known publication, must be very careful with its wording!)
3) Precisely, the reason that BEA released so quickly an outrageously and uncharacteristically accusing unsupported first report was because the swirl of filtrations. And as I wrote (I do not remember if here or on another blog), of course BEA should be aware that they cannot long sustain false positions because it will again (as you state) filter out, but is doing this only to gain time, searching for some. even if doubtful, evidence which will allow them to "correct" what they already said and possibly, as expensive lawyers do when big guns are on the stand, mud up the issues enough to let AIRBUS escape more or less unscathed
Of course: possibly I am wrong and will be glad to admit it if so, but certainly not before they release the complete transcript of the cockpit conversations!!
And you should support me be calling for the same!!
There is much to learn as to what happened with AF447. I just have to wait and follow the release of company update reports and finally, the 'official' accident investigation document. Then I can be more comfortable with any speculation(s) and skepticism it may generate within.
I will say this: Airbus Industries (initially formed by the governments of France, the UK and Germany...and joined by Spain at a later date) was formed to compete and break the manopoly that Boeing, McDonnell Douglas and Lockheed had in that world market. Has that part of the equation been successful? I would say yes as Boeing is the only one of the "Big 3" left. How would the speculation of problems (and it isn't all speculation) affect Airbus's market share? Can one see a possibility that these power based owners might have to consider controlling the release of factual information that would be damaging to their success? I'll leave you to your own speculative thoughts on that possibility.
The Big 3 merged because the end of the Cold War took away most of their business. Airbus can't claim credit for that; it is the result of a similar merger itself (of BAe [ex-British Aerospace] and its French and German counterparts, IIRC).
The other thing that helped kill the aircraft business in all these countries, including the US, is excessive "product liability" litigation. There is no such thing as a perfectly safe product of any kind, but that doesn't stop skillful lawyers from getting juries, picked to be stupid, to give them huge undeserved awards and destroying important industries in the process. If either their countries or our own are ever to have a working economy again, that ability has got to go.
Garry of the Northern Hinterland -
"But we would never know, would we?
Well, yeah, that was my point up above. There's just too many people involved for a lie to stay contained. After the way people got educated about 'tape omissions' after Watergate? They wouldn't dare. :)
Merc of the big dolphin pool,
"There's just too many people involved for a lie to stay contained."
They only found the FDR on May 1, 2011. No mention of the CVR being found, as of yet. That would give us a good look at what was happening in the cockpit and is an essential element for a full investigation. Maybe it already has been found? The possible lies/omissions, if any, are still in the infancy. Lots of time yet, Doc.
"After the way people got educated about 'tape omissions' after Watergate? They wouldn't dare. :)"
Hopefully, your 'smiley' includes a "tongue-in-cheek" component. Let's wait to see if a BEA news report says "not all the data was recoverable due to..." That might be a clue.
While I only have a few hours on my student log book (all C-150 time) I remember my flight instructor telling me that "When you want to go up, pull back. When you want to go down, pull ALL the way back". Sage advice for the uninitiated!
Skeptically yours, I remain.
If it lost the rudder it would roll off on a wing and spin in.
The investigation of JAL123 appears to somewhat disprove this statement, although it only flew for 20 minutes after the failure.
"the main being absurd accusations against (dead) pilots, but refusing to release"
These things usually aren't released for a year, sometimes two years. Go watch a bunch of disaster specials. They usually don't release any information until after the investigation is concluded. In this case, because of the frenzied mob howling outside their door, they tossed us a few tidbits.
"Vertical stabilizer found 30 miles from the flotsam"
I agree, that just deepens the mystery. Only the data recorder knows for sure. I'd guess it just snapped off from stress 10 seconds before the crash, hence the distance from the debris in that the plane was still going forward.
"an accumulation of alarm signal released just before the communications to the outside world were interrupted"
Since you're using this as a talking point, I'd respond that it wasn't "interrupted". According to the above video, the last broadcast was something like 3 minutes before the event.
"a investigation conducted without any insight by non-biased persons"
Careful, there. You're straying into Truther territory. Presuming an investigatory board is 'automatically' corrupt is kind of dicey. By way of extension, do we assume the NTSB is biased regarding domestic accidents? I certainly haven't seen any evidence of that in my recent splurge of disaster movies.
"and understand that because such nuts exist, conspiracy nevertheless exist too!"
Even paranoids have enemies. :)
"Beginning with the German Magazine DER SPIEGEL"
Sorry, I should have said authentic rumors. Like, from the lab technician's wife's best girl friend. Der Spiegel isn't passing along rumors, it's creating them. Aka "good journalism".
"Precisely, the reason that BEA released so quickly an outrageously and uncharacteristically-"
Now hold on a sec. I remember seeing you there with your "WE WANT THE TRUTH NOW!!!" placard, so they give you a little something and suddenly it's 'outrageous' and 'uncharacteristic'?
In other words, if they only release some information, it's a "cover-up", but if they withhold all information, it's a "cover-up"? Have I got that right?
"And you should support me be calling for the same!!"
I said twice in the post that 'we'll just have to wait and see'. It should be fascinating to watch it play out on the international stage.
You cannot synthesize airspeed from GPS unless you have precise knowledge of the wind at that position. GPS units already display groundspeed; you'd need to add in the appropriate wind component to get airspeed.
The point is that you can compute the wind from the GPS readings and aircraft parameters (like power, heading and pitch), especially given a setup period with measured airspeed data available.
That's what a Kalman filter does more or less automatically.
You ought to be able to get the wind to a few mph pretty easily.
If you know the groundspeed (from gps, ins, or whatever) AND the airspeed, you can compute wind. But the problem here is that you don't know airspeed, and you can't really assume wind remains constant after a setup period.
If you could reliably estimate airspeed from pitch and power, you wouldn't need groundspeed to do it, although gps-derived rate of climb might be helpful. You would need aircraft weight, any flaps, gear or other drag-producing devices deployed. Have to think about this a bit.
Another approach might be a deplorable flat plate on which the force could be measured. Much less accurate than pitot tubes, but should be much more ice-proof than those little holes.
The performance of the plane and its GPS position depend on the winds; therefore the winds can be deduced.
The Kalman filter just formalizes how you do that dynamically.
Generating a VLF electromagnetic wave requires huge tuned circuits. At 20 kHz a wavelength is 15 km and the antenna must be an appreciable portion of a wavelength to radiate. You aren't going to put a vlf transmitter in a bleck box. Here are some pictures of a USN vlf transmitter. Note the size of the tuned circuits.
Ray - Interesting pics, thanks. What a monster! But as we discussed up above, we're not talking about reaching halfway around the world like a sub needs to, just 13,000 feet to the surface. And I just tossed out "VLF" as an example, but what I meant was that ANYTHING would be better than what they're using. If it doesn't work in an ocean crash, which is where you need it the most, then what's the point?
Hey Ray...hey Merc,
Part of what the discussion was (IMO): do we trust guvmt reports (amongst other things).
I heard Sarah Palin was actually born in Mozambique.
Pass it on.
I forgot U could speak 'a la Francais". Good show!!