Malaysia Airlines Flight 370 (Boeing 777) disappeared on March 8, 2014 along with 239 passengers and crew during a flight from Kuala Lumpur to Beijing, sparking the most expensive search in aviation history (Paul, 2014). After 20 days of searching for the missing Boeing 777 (B777) using manned aircraft and marine vessels, a relatively new unmanned search method was explored utilizing the Bluefin-21. Angus Houston, retired Australian air chief marshal, who is head of the joint agency coordinating the search, said "the Bluefin-21 will be deployed, creating a sonar map of the area to chart any debris on the sea floor" (ABC, 2014).
The Bluefin-21 is a highly modular autonomous underwater vehicle (AUV) able to carry multiple sensors and payloads at one time (Bluefin, 2015). What makes the Bluefin-21 an easy choice for a maritime environment search effort, respectively underwater within the Indian Ocean; is this particular AUV carries a robust energy capacity allowing for extended underwater operations at increased depths. It is equipped with a stout sensor suite consisting of a high-performance 455 kHz side scan sonar, Synthetic Aperture Sonar (SAS), Multibeam Echosounders (MBES), imaging sonar, and Sub-Bottom Profiler (SBP) (Bluefin, 2015). The sonar systems were particularly useful as it employs sound waves to explore and map the ocean floor in search of aircraft wreckage (NOAA, 2104). Used in this forum, the sonar was key in the exploration of more than 120-square-miles of ocean floor (CBS, 2014).
The Bluefin-21 uses a proprioceptive Inertial Navigation System (INS) for course guidance underwater (Bluefin, 2015). The use of Global Positioning System (GPS) for navigation most assuredly would not work underwater, leaving INS as the best choice. The AUV INS uses accelerometers and gyroscopes to track changes in direction and speed. It is aided by an Ultra Short Base Line (USBL) transponder which provides acoustic signal updates in relation to its position. An above water marine vessel intercepts the signal, interrogates it and makes adjustments as needed for AUV course direction; resulting in an astonishing dead reckoning drift of less than 0.1% (Bluefin, 2015).
As we now know, the vast search efforts did not yield the location of the missing B777 and uncovered very little evidence of what exactly went wrong. Even though the Bluefin-21 scoured vast amounts of ocean floor it to fell short of finding any real evidence. I believe this was due to a combination of the AUV's narrow sonar scope and the extremely large search area. Perhaps if the Bluefin-21 was able to dive to even deeper depths (like the Remus 6000) covering many of the seafloor depressions (6,000m or 20,000ft) in the search area, something might have revealed itself on the respective imagery.
Aiding in the search were many manned aircraft flying over thousands of square miles of Indian Ocean. The operational logistics of conducting flight efforts for this particular search must have been very daunting. There are many reasons why utilization of an Unmanned Aircraft System (UAS) would have been extremely beneficial in the search efforts. Using UAS(s) would enable an increase in flight time, thus, allowing for increased ocean surface coverage. Using a UAS to determine points of interest on the ocean surface could in fact be relayed to the Bluefin-21 controlling vessel; reducing the search area significantly by concentrating efforts within this particular relay point.
Even though 99% of search efforts have discontinued and many families are left with more questions vice answers; there were some positives in an unmanned system application usage standpoint I would like to address. Using the Bluefin-21 in this search effort yielded a far greater coverage area then if a manned system was used. The advantages of the unmanned system enabled increased human safety and substantial cost savings over its manned counterpart. The ocean depths are mostly unknown, and permitting a manned vehicle to perform this particular deep sonar mission, only puts more human lives at risk; the possible loss of additional lives is mitigated by the use of an unmanned system. The use of either a manned system or unmanned system regarding its sensor suite is equal in this respect; however, the introduction of a manned system, again, puts the potential loss of human life at risk.
My prayers still go out to the families of Malaysia Airlines Flight 370, and I hope for a resolution sometime in the near future to all the unanswered questions.
References
Paul Tait (2014, April). Malaysia Airlines Missing Plane Search Halted Again
Over Technical Problems. Retrieved from http://www.huffingtonpost.com/
ABC News (2014, April). Bluefin-21 Sub Launches Deep Dive in Flight 370
Search. Retrieved fromhttp://abcnews.go.com/
Bluefin Robotics. (2015, May). Bluefin-21. Retrieved fromhttp://www.bluefinrobotics.
NOAA (2014, Jan 23). What is sonar? Retrieved fromhttp://oceanservice.noaa.gov/
CBS (2014, Apr 25). Malaysia Airlines Flight 370 sonar scan nears completion
without trace of missing Boeing 777. Retrieved fromhttp://www.cbsnews.com/news/
mpletion-no-trace-of-boeing-
Excellent review of the Bluefish-21 Garrick!
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