RQ-4B Global Hawk vs Bluefin AUV
RQ-4B Global Hawk
In this post, I would like to compare command and control systems for the RQ-4B Global Hawk and the Bluefin Autonomous Underwater Vehicle. According to the Operation Test Report by Gilmore, M. J. (2012), the RQ-4B includes a wideband Ku-band SATCOM data link. This system uses satellites to fly the aircraft from a ground station anywhere in the world. The RQ-4B also carries an INMARSAT system to provide backup C2 in the event of a loss of the Ku link.
A likely influence for the use of Ku-band SATCOM to control the RQ-4B was for the requirement to fly the aircraft around the world without having a line of sight link. This would allow the platform to operate anywhere within a satellite’s footprint. This would allow for high bandwidth for reconnaissance data to flow back to the operators while continuing to collect more data.
Bluefin AUV
The Bluefin operates underwater after receiving a mission plan and location updates from a ship or GPS. The ship that is controlling the system uses a line of sight or an Iridium satellite connection to upload or modify the mission plan before the Bluefin descends. Once the system is ready to launch, it dives down underwater. During its scanning, the Bluefin continuously receives location corrections via the ship above. The system will update its INS with those updates and continues its mission planned collection.
Influence of the Bluefin’s ship-based navigation correction is likely due to the inability of RF waves to penetrate deep into the water. The ship above can more easily transmit location updates to the AUV than a GPS satellite when the system is deep underwater. The use of an INS system uses correctional updates from the ship since it won’t be able to receive GPS data when it is deep underwater.
With the limitations of GPS underwater, the use of an INS and updates from a ship are critical. The use of this type of system would not be feasible for the RQ-4B. With the ability to travel anywhere on Earth, the RQ-4B would not be capable of flying with position updates from a ground station or ship below. The lack of range on this type of system would not favor the RQ-4Bs reach due to the line of the sight of the Earth as the aircraft leaves the area where it would receive updates. Conversely, the Bluefin would not be able to receive SATCOM updates or commands from the operator due to the lack of RF penetration from the satellites.
References
General Dynamics.Bluefin robotics unmanned underwater vehicles - general dynamics mission systems. Retrieved from https://gdmissionsystems.com/underwater-vehicles/bluefin-robotics
Gilmore, M. J. (2012). RQ-4B Global Hawk Block 30 Operational Test and Evaluation Report. Department of Defense, http://pogoarchives. org/m/ns/pentagonot-and-e-eval-rq-4b-global-hawk-20110526. pdf
PetroPages Industrial Marketing (Producer), & . (2013, April 24). BLUEFIN robotics 3D animation. [Video/DVD] Retrieved from https://www.youtube.com/watch?v=Dbfwwv47w4Y&feature=youtu.be
RQ-4 global hawk. (2014). Retrieved from https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104516/rq-4-global-hawk/