A mini-sub hunting for Malaysian jet MH370 aborted its first search of the remote Indian Ocean seabed after just six hours because the water was deeper than its operating limits, officials said Tuesday.
Posted on 04/14/2014 9:29:42 PM PDT by OneVike
A mini-sub hunting for Malaysian jet MH370 aborted its first search of the remote Indian Ocean seabed after just six hours because the water was deeper than its operating limits, officials said Tuesday.
The unmanned submarine loaded with sonar to map the ocean floor deployed Monday night from the Australian ship Ocean Shield which has spearheaded the hunt for the Boeing 777 that vanished on March 8.
"After completing around six hours of its mission, Bluefin-21 exceeded its operating depth limit of 4,500 metres and its built in safety feature returned it to the surface," JACC said, without detailing the exact depth of operations.
"The six hours of data gathered by the Autonomous Underwater Vehicle is currently being extracted and analysed," JACC said.
The AUV had been due to spend up to 16 hours collecting data.
US Navy Captain Mark Matthews explained the vehicle had exceeded its programmed operational limit and automatically resurfaced.
"There's certain abort criteria that the vehicle has as it's executing its mission," he told CNN from Perth.
"If there's certain conditions that occur, it stops and it comes to the surface.
"In this case the vehicle's programmed to fly 30 metres over the floor of the ocean to get a good mapping of what's beneath."
Charts put the depth at 4,200-4,400 metres, he said.
"It went to 4,500 metres and once it hit that max depth, it said this is deeper that I'm programmed to be, so it aborted the mission."
Matthews, a search and recovery expert, said the crew would now refine the task to cope with the depth encountered.
"It happend in the very far corner of the area it's searching. So they are just shifting the search box a little bit away from that deep water."
(Excerpt) Read more at emirates247.com ...
the problem remains, that there is no debris.in teh ocean. they will continue to search there, because they dont want to come to the other conclusion.
Lol! Yeah, I know. A lone seamount got in his way, but the overall general depth is known.
You're starting to catch on.
Depths for SURFACE navigation on much of the ocean ARE well charted, but the abyss and sea-mounts, if they are in an area of widely separated soundings, are not necessarily so.
Neither are the deeps, because no one goes there.
I have spent this time to point out that your "SHEESH!" post was inappropriate and uninformed (as opposed to politely curious and inquisitive).
See this NOAA Chart 531 and note there are commonly 40NM intervals between soundings. (takes a little while to load - pan and zoom at the upper left) )
Uhm, there are satellites that can measure sea depth from space.
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter03/chapter03_04.htm
It looks like your post was inappropriate and uninformed.
The Figure 3 label includes: Note the large areas where depths have not been measured from ships. (ref my previous post)
There is not any claim of detailed accuracy, but the graphics make it obvious that the Geoid undulations on the surface cannot possibly indicate sharp anomalies in the sea floor such as narrow, deep canyons or relatively small (but significantly deeper basins.
After all, these features are NEVER observes on the surface.
Here is another page on satellite imaging of the ocean.
Please note the Prediction of Seafloor Depth section which explains that satellite altimeter measurements (converted to depth measurements) are not very accurate and are not used to assess navigational hazards but are used in combination with sparse (surface) measurements of seafloor depth to construct a uniform resolution map of the seafloor topography.
Yours Sincerely for Accurate and Informed posting . . . . . .
That was the whole point-there are other ways of mapping that DON’T rely on ships.
Your original comment: It sounds like very poor planning, given that the worlds oceans are pretty much mapped as to depth. Sheesh.
That was in response to the post that included:"In this case the vehicle's programmed to fly 30 metres over the floor of the ocean to get a good mapping of what's beneath." Charts put the depth at 4,200-4,400 metres, he said.
In other words, the operator correctly programmed the Bluefin-21 with the depth parameter on the official charts, but those depths are not generally charted from closely spaced soundings and that do not show much deeper or shallower areas (as I have repeatedly explained). This is quite possible in the very deep parts of the ocean.
So, since the Bluefin-21 is autonomous the only way to prevent it from diving too deep is to program an abort depth, since its course and depth are pre-programmed and not controlled in real time from the surface.
Once again, there is nothing in the post that suggests anything like very poor planning involved here.
Finally, if you still want to argue, read the full artcle which includes the section:
Mysterious and unmapped
It has not been mapped -- in fact most of the deep ocean has not been mapped," Charitha Pattiaratchi, an oceanographer at the University of Western Australia, said of the search area.
"It is very cold and dark with high pressures -- 450 times that at the surface."
Experts cannot even agree on the nature of the seascape, variously described as flat, rocky or coated in super-fine silt that could envelop and hide wreckage.
—SIGH— Go to the Oceaneering website and see how THEY conduct a search. I’m sure you’ll agree it’s POOR planning.
The Oceaneering site is quite impressive, but they proudly claim their record ROV ultra deepwater drill support depth record is only 3185 meters (10450 feet).
The Bluefin 21 came back from 4500 meters (14,764 feet), which is 1315 meters (4314 feet) DEEPER!! And there was no indication that it can't go deeper than that, only that it was programmed to abort at 4500 meters on that mission.
Please pause to contemplate we are talking 8/10ths of a stature mile DEEPER than the Oceaneering's record claim.
Again, we are comparing tethered ROV's with autonomous subs.
Deepwell, dredging,pipeline and BOP services v.s. an autonomous imaging sub. Two totally different services. The Bluefin 21 does only imaging and data collection. Their ROV's actually install and repair things with real time imaging. But Bluefin 21 operates at MUCH deeper depths.
You are in a hole, and you keep digging it deeper and deeper.
Thank you for your sexist statement. The first thing any deep water recovery co. does is check the depth of the likely spots they will be searching in. Then they choose an ROV capable of reaching as deep or DEEPER than that. There are ROV’s than can reach 20,000 ft or more. If the search party involved in this chose an ROV incapable of diving to deeper depths, that is a result of poor planning. Congratulations on making a mountain out of a molehill.
The first thing any deep water . . . ..
They consulted the charts and deployed. They found the actual depths a little deeper, but everything worked and today, the Bluefin 21 submerged on its fifth 16 hour dive (24 hour mission cycle).
There are ROV’s than can reach 20,000 ft or more . . .
More than 35,500 feet, actually. MANNED submersibles have reached the deepest point in the ocean (Trieste c.a. 1960 and an Australian effort a couple of years ago). However, they would be totally inappropriate for this MH370 search.
Did I mention that the Bluefin 21 is working as planned on its 5th consecutive day since deployment? Notice I'm not making any predictions, simply reporting the ops normal status to this point.
—SIGH— Go to the Oceaneering website and see how THEY conduct a search . . . I would still like to see that Oceaneering website page and I've spent some time looking, but I need your help finding it.
Congratulations on making . . . .
Molehills to mountains, eh? . . .well congrats to you on the endurance of your shuck and jive.
Whatever makes you happy dear.
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