Latest JACC media release
 

Media Release
16 April 2014—pm

The Autonomous Underwater Vehicle, Bluefin-21, was forced to resurface this morning to rectify a technical issue. While on deck, its data was downloaded.

Bluefin-21 was then redeployed and it is currently continuing its underwater search.

Initial analysis of the data downloaded this morning indicates no significant detections.

Just a question of interest.

In order to scan equidistance each side of the fish it is obviously essential the vertical axis remains vertical. I haven't seen any stabilisers on the pictures of it , so how does it do that? Gyros and mini thrusters?

For Heavens' sake!

Bluefin-21 » Bluefin Robotics

"Specs"

There, there. That wasn't difficult, now was it?

It has a vertical stabilizer that can be seen on the photos
Search for MH370: Underwater vehicle Bluefin-21 deployed to find plane's wreckage
To me it looks like a swimmer on top of the "fin". Technically it make more sense to have a flat bottom an a swimmer on top than a keel.

WillowRunAF447 transmitted Acars - including position - to the satellite, MH370 didn't, its Acars were VHF only and that function was disabled. It's probably the first time possible positions have been calculated using the timings of the handshake - which were for the satellite telephone only.

I understand that the "technical issue" was an over depth or over pressure situation. Evidently the Bluefin follows the bottom at a specific height above the ocean floor and if in so doing it gets too deep it aborts the mission and returns to the surface.

Frankly I'm shocked at how limited the programming is on the Bluefin. Returning to the surface is a huge waste of time and near as I can tell the 2nd worst possible outcome. The worst would be self destruction from over pressure, at least that didn't happen.

I would think that just maintaining a safe depth and skipping over the sections that are too deep would be preferable. Turning around to avoid the deep sections would work as well. This silly thing is kinda like a Roomba that shuts off if it hits a wall...

Putting on my McKayla "not impressed" face...

Source?

The "overdepth" situation occurred when the vessel re-surfaced early during the first deployment. It was then re-programmed (presumably to avoid this situation from happening again) and re-deployed. It then re-surfaced early again during the second deployment due to a technical issue that was not specified in more detail.

Looks like the mission was aborted a 3rd time...

They should be simply flying the fish at its working depth, and forget skimming the bottom.

The sidescan can fly quite a bit higher and still have great res.

News and links
 

>Looks like the mission was aborted a 3rd time...

I have found mention of two attempts but not three. This and many other posts include bits of information but no source. The slow pace of new information is resulting in a lot of invented stories prompted by reporters' deadlines, old news, patently false news, and theories disguised as news. Major news organizations are as apt to do this as sensationalist news organizations. Excepting press conferences from the search authority, claims of 'new' information do not mean that information is accurate. New 'news' must wait for corroboration to become accurate.

It would be very helpful to me and I imagine many thousands of others if posters here would include links to the stories they cite.

Even better would be for posters to report information sources they have found to be consistently accurate, timely, and resistant to inventive journalism.

Had you thought of giving AVM Houston a call and offering your nuggets of wisdom?
Those operating this sophisticated equipment obviously fall short of your level of expertise:ugh:

Reliable Sources requested
 

The most obvious one is JACC

Media

I designed part of the Bluefin 21 guidance system.

I also designed one for telecommunication cable mapping with a sidescan, mag, and sub-bottom profiler.

We do this stuff everyday, not once a decade when they lose an aircraft.

Concisely put. I hope your post survives.
Uh, right. :uhoh: "Never happen again" is nice bloviation, not so much on reality.
Granted, this is a novel occurrence, albeit tragic.

Considering the size of the search area, I think some folks are getting impatient, without good reason, over the search and its results.

Here is the news extract from Bluefins operators.

"In Quincy, Mass., near the city's historic shipyard, one of the world's most innovative deep-sea explorers is being but to the test. Called the Bluefin-21, the submersible vehicle can descend two-and-a-half miles below the ocean's surface to some of the most inhospitable places on the planet.
David Kelly, chief executive officer of Bluefin Robotics - a company that specializes in deep sea exploration - said, "The temperature's about slightly above freezing; it's pitch black. The pressure there is the equivalent of having a Cadillac Escalade balanced on your thumbnail."
One of the Bluefin's submersibles, owned by a U.S. Navy defense contractor, is now aboard the Australian vessel Ocean Shield in the southern Indian Ocean.
Now that a signal has been received, the torpedo-like craft will be soon be put to work. It will scour an area the size of Texas at a rate of 40 square miles each day.
Kelly explained, "Down there, it'll run what's called a lawnmower pattern. It's just like mowing the lawn at your house."
On each "mission," the craft uses sonar technology to scan the ocean floor. Those sounds create images that researchers analyze when the craft resurfaces once every 24 hours."

And here is my simple arithmetic.

Texas has a surface area of 268,820 sq.m , divide this with 40 and the result is 6720 days, give or take a few, how many years is that? All assuming it is beavering away around the clock every day and no down time for maintenance, technical hitch or weather, of course. Now that to me sounds just a touch too much "lawnmowing".

Being in the business, you would certainly know of Phoenix International, the civilian contractor for the USN. Any comments on their capabilities?

The second Bluefin 21 snag was due to low oil in one of the batteries - I believe this is to prevent collapse under the extreme pressure b ut that's conjecture on my part.

The BF 21 is the civilian version, which is why PHI is involved.

The capabilites of PHI speak for themselves.

EDIT: Due to the depth, all of the systems on the fish are oil filled, replacing any air.

Some cause for optimism
 

According to wreck hunter David Mearns, Searchers have pinpointed Malaysia Airlines flight MH370 crash site.

Not official, of course, but at least a view from someone with some experience in the field. It is, perhaps, some cause for optimism - to the extent that you can be optimistic about finding 239 dead people and a wrecked aircraft.

I don't think there is anything new here except of the boastful title, the guy is making a fairly stretched claim that since they had 4 strong "transmissions" they "pinpointed" the crash site. Even if such claim is warranted, we knew this over a week ago. Frankly at this point - only a solid sonar (or other) picture would justify such loft claims.

Not sure if this has been posted before.

"Authorities in Perth are testing an oil sample collected from the search zone of the missing Malaysia Airlines plane."

So we are likely to know by the end of Easter if it is from the aircraft.