Been reading this thread since June 1. The blend of fact and speculation has been just about right for a situation where facts are scarce, the unknowns are plenty, and the need-to-know is high. I'm sure that all you drivers get pretty focused, now, when cosying toward the coffin corner at FL370 and mach .8, asking yourself "what if" questions and wondering if you will be unexpectedly flying "tight ass," the way Google translated a French captain's comment earlier in this thread, describing his sudden high-altitude Direct Law flying experience, before the post was edited to read "seat-of-the-pants."
For those following this thread (over a thousand visitors at this very moment) who are interested in the needle-in-the-haystack problem (locating and raising the FDR and CVR from the deeps of the Atlantic Ocean), you should know that mounting such a subsea salvage operation is a HUGE undertaking requiring incredibly specialised gear, support vessels, large crews, scientific expertise, and lots of money. The NTSB and the FBI spent USD31.4 million on TWA Flight 800 (
TWA Flight 800 - Wikipedia, the free encyclopedia and
Air France Crash Update ? Deep-Sea Robots Could Recover Air France's Black Box - Popular Mechanics). BEA head Paul-Louis Arslanian is not optimistic.
Task: Find the aft section of the A/C. Assuming the FDR and CVR were not ejected, that's where the pinger(s) are mounted.
By June 16th, the Brasilian team seems to have narrowed the visual search area (area de busca visual) to a 19,000 sq. km swatch westward of TASIL (see above or link to original at
http://www.fab.mil.br/portal/voo447/...iva_160609.ppt). As RuddA pointed out earlier in this thread (#1374), backplotting ocean current drift and wind effect on debris is tricky, so acoustic trawling for the pinger may actually be going on in a swath as far as 200km eastward of the search for debris and remains. I have been a USCG licensed Merchant Marine Officer (Master) and also a Private Pilot for the last 30 years, mostly navigating in 2-dimensional space, and I can tell you that even with the most up-to-date current charts, weather reports, and the best local knowledge (not much of that mid-ocean), it's still a reverse-dead-reckoning set-and-drift calculation with sometimes unknown margins of error. Sort of like using a bubble sextant or wind triangle to update your ground vector every 300km based on TAS and heading, but in reverse (those Navigators have gone to the same place as the cockpit Flight Engineers). I'm sure the Brazilian/French team has spent hundreds, more likely thousands, of navigator man-hours best-guessing the "Ultimo Reporte" location and the debris drift.
It's pretty deep. Thousands of fathoms deep. And the terrain, near the Mid-Atlantic Rift (MAR), can be steeply mountainous (escarpment "slopes of at least 30o, with slopes up to 50o being common and maximum slopes reaching more than 60o" (
Mid-Atlantic Ridge 29oN: New Insights on Ridge-Axis Faulting From High-Resolutio)). Dutch tugs chartered by the French Accident Investigation Authority (FAIRMOUNT EXPEDITION and FAIRMOUNT GLACIER - (
Fairmount Marine B.V.)) are towing U.S. Navy listening sensors. The French nuclear sub, EMERAUDE (
http://images.tvnz.co.nz/tvnz_images...ubmarine_2.jpg) is searching and listening. Pinger batteries may be dead in another two weeks, they say.
Without the pinger(s) it gets harder, but perhaps not impossible, to locate the wreckage. Towed Ocean Bottom Instrument (TOBI -
TOBI) might be able to resolve the wreckage from the sea floor topography after the pingers quit. 30kHz sidescan sonar with swath bathymetry capability, chirp sub-bottom profiler, three-axis high resolution magnetometer and an across track resolution of 2 meters could image a fuselage or wing(s) - A330 wingspan is 60.3 m (197 ft 10 in). For more on using this technology, see Searle, R. C. (
Mid-Atlantic Ridge 29oN: New Insights on Ridge-Axis Faulting From High-Resolutio) and D. K. Smith (
Viewing the Morphology of the Mid-Atlantic Ridge From a New Perspective). A decade ago Smith mapped the seafloor along the MAR some 25 degrees northward from TASIL:
Task: Recovery
Two French deep-dive manned submarines, 8m-long NAUTILE (
Nautile) and its sister, the VICTOR 6000, and their support vessel (the POURQUOI PAS) are standing by (
Business Report - French submarine has all the right credentials to lead search operation), ready to recover the FDR and CVR. NAUTILE worked the TITANIC wreck with two retractable manipulation arms and a sampling basket.
This is a non-speculative status report dealing with the big picture and, I hope, with helpful links to detailed references. With respect to BreezyDC (#1886), I'd like to believe that in this particular case professional pilots are, indeed, interested in more than ACARS message sequencing, TCAS, FBW, weather radar, joysticks, and SOPs, as important as these discussions are. As SLF for more than a million miles, I'd rather fly with somebody in the left seat who has looked at *all* the material presented in this thread and taken reflective time to "noodle" through the many "what-ifs" -- someone with an agile mind (quick and always curious). Already, there are lessons learned and new AB-type pitots are (being) installed.
On the other hand, BreezyDC, you are probably right: perhaps time to restart this almost 100-page thread in a couple of new directions... Aside from progress reports or a "Found It!" announcement, might have to wait until the official required prelim report end of the month, and maybe not much will emerge, even then.
Let's hope that the batteries last, that the FDR and CVR haven't imploded, that the wreckage isn't jammed tail-first into a subsea ravine, and that the BEA has deep pockets. At this very instant, thousands of people are on the ground and on the water helping to better understand what the ACARS told us, what the debris and remains tell us -- and why. We are but two weeks into a catastrophic event that, for some, will never end.