Command, Control, and Communication (C3) of Unmanned Aerospace Systems (UAS) in the National Airspace System (NAS)

Command, Control, and Communication (C3) of Unmanned Aerospace Systems (UAS) in the National Airspace System (NAS)

 by

Daniel J. Hall, Jr.

In Partial Fulfillment of the Requirements for

ASCI 530

 Embry-Riddle Aeronautical University

November 15, 2013

Command, Control, and Communication (C3) of Unmanned Aerospace Systems (UAS) in the National Airspace System (NAS)

Integration of unmanned aerospace systems (UAS) into the National Airspace System (NAS) is a necessary step in realizing the commercial benefits of these systems.  However, methods of command, control, and communication (C3) need to be addressed in order to safely operate UAS in an already congested airspace.  “UAS operations are currently not authorized in Class B airspace, which exists over major urban areas and contains the highest density of manned aircraft in the National Airspace System” (Federal Aviation Administration, 2013a, para. 5).  Fortunately, the benefits of switching from a ground based surveillance system to a satellite based surveillance system as promised by NextGen significantly enhances UAS C3.  For example, “Automatic Dependent Surveillance-Broadcast (ADS-B) is FAA's satellite-based successor to [ground based] radar.  ADS-B makes use of GPS technology to determine and share precise aircraft location information, and streams additional flight information to the cockpits of properly equipped aircraft” (Federal Aviation Administration, 2011, para. 1).

Until the functionality of NextGen is fully implemented, current UAS C3 systems such as Global Positioning System (GPS) navigation and Traffic Alert and Collision Avoidance Systems (TCAS) could be combined with routing methodologies to ensure separation of manned and unmanned aircraft.  For example, in addressing this issue, the Department of Defense (2011) detailed the following six routing methods to be employed by the suggested UAS groups:

Visual Line-of-Sight (VLOS) – UAS Groups 1, 2, and some 3 - The observer can be located on the ground, in a moving vehicle/boat, or in a chase plane. (p. 10)

Terminal Area Operations - All UAS Groups - The observers or sensors alert the UAS pilot/operator of approaching traffic so actions may be taken to avoid potential collisions with other traffic. (p. 11)

Restricted Operating Areas – All UAS Groups – Nearly 500 existing [Military Operating Areas] MOAs can provide DOD UAS the ability to span 43 states and over a half million square miles of operating space. (p. 13)

Lateral Transit (Corridor) Operations – UAS Groups 3, 4, and 5 – consist of flying from one controlled airspace to another through a pre-defined corridor.  The corridors can potentially be implemented at any altitude, but typically reside in Class E airspace (above 1200 ft. AGL, but below 18,000 ft. MSL). (p. 14)

Vertical Transit (Cylinder) Operations – UAS Groups 4 and 5 – consist of a spiral climb or descent to within controlled airspace to/from Class A controlled airspace (18K – 60K feet) or a designated corridor altitude. (p. 15)

Dynamic Operations – UAS Groups 3, 4, and 5 – envisions that the UAS will possess the ability to integrate routinely into the NAS comparable to today’s manned aircraft.  This concept enables the proponent of an appropriately equipped UAS to file a flight plan and then perform the activities listed in that flight plan with unfettered accesses to the airspace. (P.16)

The Federal Aviation Administration (2013b) stated:

Ultimately, UAS must be integrated into the NAS without reducing existing capacity, decreasing safety, negatively impacting current operators, or increasing the risk to airspace users or persons and property on the ground any more than the integration of comparable new and novel technologies. (p. 4)

The author suggests that commercial integration of UAS into the NAS is possible with current C3 technology and capabilities when combined with variants of the routing methods describe above.

References

Department of Defense. (2011, March). Unmanned aircraft system airspace integration plan (Version 2.0). Retrieved from http://www.mtsi-va.com/docs/Airspace_Integration_Plan_2011.pdf

Federal Aviation Administration. (2011, November 2). NextGen: A strong nucleus. Retrieved from http://www.faa.gov/nextgen/slides/?slide=4

Federal Aviation Administration. (2013a, February 19). Fact sheet – Unmanned aircraft systems (UAS). Retrieved from http://www.faa.gov/news/fact_sheets/news_story.cfm?newsId=14153

Federal Aviation Administration. (2013b, November 7). Integration of civil unmanned aircraft systems (UAS) in the National Airspace System (NAS) roadmap (1st ed.). Retrieved from http://www.faa.gov/about/initiatives/uas/media/UAS_Roadmap_2013.pdf

Delivering Pound for Pound Performance in a Precision Crop-Dusting UAS

Delivering Pound for Pound Performance in a Precision Crop-Dusting UAS

by

Daniel J. Hall, Jr.

In Partial Fulfillment of the Requirements for

ASCI 530

Embry-Riddle Aeronautical University

November 1, 2013

Delivering Pound for Pound Performance in a Precision Crop-Dusting UAS

The use of commercial off-the-shelf (COTS) hardware is commonplace in the design and development of unmanned aerospace systems (UAS).  The acronym COTS, within the context of this paper, refers to aviation systems, subsystems, and components available for purchase on the open market.  Sadraey (2013) stated, “In order to minimize cost, it is recommended to select standard parts that are commercially available (i.e., commercial off-the-shelf items) for which there are multiple viable suppliers” (p. 32).  The use of COTS hardware enables the UAS developer to focus on the air vehicle as a collection of systems rather than spending resources on the design and development of each individual system, subsystem, and component.  This approach usually accelerates the design and development process, while reducing cost.

During the design of the precision crop-dusting UAS several errors were made resulting in an overweight condition often faced by aviation systems engineers.  Nicolai and Carichner (2010) stated:

It is almost impossible to estimate the empty weight of something that has not been built (usually with new subsystems and structural materials) with any degree of accuracy.  However, it is important to press on or the aircraft will never be designed. (p. 125)

In this case both design teams should have been more cognizant of their weight budgets and the impact their COTS hardware would have on the final product.  Sadraey (2013) emphasized:

First and foremost, it must be emphasized that any engineering selection must be supported by logical and scientific reasoning and analysis.  The designer is not expected to select a configuration just because he/she likes it.  There must be sufficient evidence and reasons which prove that the current selection is the best. (p. 10)

At this point the system engineers must reevaluate the requirements and specifications stipulated by the customer to ensure they are working towards the desired goals.  Sadraey (2013) wrote; “From the perspective of systems engineering, the design of aircraft should not only transform a need into an air vehicle, but also ensure the aircraft’s compatibility with related physical and functional requirements” (p. 22).  The design team needs to meet with the customer and ensure they understand the requirements and specifications that are absolutely necessary and the requirements and specifications that are flexible.  Perhaps the customer will accept compromises in a design aspect that could save the necessary weight.  For example, the design team may discover the customer really wants the capabilities offered by the COTS hardware and is willing to compromise on the fuel capacity.

If the stated requirements and specifications are absolutely necessary then the system engineers must find a means to meet the weight budget.  This would entail a review of not only the COTS hardware systems in question but all systems on the proposed UAS.  It may be possible to reduce weigh in the airframe, propulsion, or flight control systems.  Sadraey (2013) described this type of analysis as a “trade-off analysis” (p. 28).  “As the name implies, trade-off analysis involves both gains and losses; the gains have to be maximized, and the losses must be minimized.  Trade-off is a compromise made between two or more favorable alternatives” (Sadraey, 2013, p. 28).  Ultimately, a means must be found to meet the customer’s requirements and specifications.  If this is not possible then the system engineers must inform the customer of all available options in order to make a decision on whether to pursue the UAS development or cancel the project.  However, in this case it appears the system engineers have identified the issue early enough in the design process that an acceptable solution can be found and a precision crop-dusting UAS developed, tested, and delivered to the customer.

 

References

Nicolai, L. M., & Carichner, G. E. (2010). Fundamentals of aircraft and airship design. Reston, VA: American Institute of Aeronautics and Astronautics.

Sadraey, M. H. (2013). Aircraft design: A systems engineering approach. Chichester, UK: John Wiley & Sons Ltd.