Unmanned Aircraft Systems:

DOD Needs to More Effectively Promote Interoperability and Improve Performance Assessments

GAO-06-49: Published: Dec 13, 2005. Publicly Released: Dec 13, 2005.

Additional Materials:

Contact:

Sharon L. Pickup
(202) 512-9619
contact@gao.gov

 

Office of Public Affairs
(202) 512-4800
youngc1@gao.gov

Unmanned aircraft systems (UAS) consist of an unmanned aircraft; sensor, communications, or weapons, carried on board the aircraft, collectively referred to as payloads; and ground controls. UAS have been used successfully in recent operations, and are in increasingly high demand by U.S. forces. To meet the demand, the Department of Defense (DOD) is increasing its investment in and reliance on UAS, and often deploying them while still in development. GAO has previously found that DOD's approach to developing and fielding UAS risked interoperability problems which could undermine joint operations. GAO was asked to review (1) UAS performance in recent joint operations and (2) the soundness of DOD's approach to evaluating joint UAS operational performance.

DOD has achieved certain operational successes using UAS, including identifying time-critical targets in Iraq and Afghanistan, and striking enemy positions to defeat opposing forces. Some missions effectively supported joint operations, and in other cases, the missions were service-specific. DOD has encountered challenges which have hampered joint operations at times. First, some UAS cannot easily transmit and receive data with other communication systems because they are not interoperable. Although DOD guidance requires interoperability, detailed standards for interoperability have not been developed; DOD has relied on existing, more general standards; and the services developed differing systems. For now, U.S. forces have developed technical patches permitting transmission but slowing data flow, potentially hampering time-critical targeting. Second, some sensor payloads cannot be interchangeably used on different UAS because DOD has not adopted a payload commonality standard. Some UAS missions may have to be delayed if compatible unmanned aircraft and payloads are not available. Based on its experience with UAS in Persian Gulf operations, U.S. Central Command believes communications interoperability and payload commonality problems occur because the services' UAS development programs have been service-specific and insufficiently attentive to joint needs. Lastly, the electromagnetic spectrum needed to control the flight of certain unmanned aircraft and to transmit data is constrained and no standard requiring the capability to change frequencies had been adopted because the problem was not foreseen. Thus, some systems cannot change to avoid congestion and consequently some missions have been delayed, potentially undermining time-critical targeting. In addition to the joint operational challenges, inclement weather can also hamper UAS operations. Unmanned aircraft are more likely to be grounded in inclement weather than manned aircraft and DOD had not decided whether to require all-weather capability. While DOD has acknowledged the need to improve UAS interoperability and address bandwidth and weather constraints, little progress has been made. Until DOD adopts and enforces interoperability and other standards, these challenges will likely remain and become more widespread as new UAS are developed and fielded. DOD's approach to evaluating UAS joint operational performance has been unsound because it was not systematic or routine. DOD has deployed UAS before developing a joint operations performance measurement system, even though results-oriented performance measures can be used to monitor progress toward agency goals. DOD has generally relied on after-action and maintenance reports which have useful but not necessarily joint performance information. DOD has also relied on short-duration study teams for some performance information but had not established ongoing or routine reporting systems. Thus, while continuing to invest in UAS, DOD has incomplete performance information on joint operations on which to base acquisition or modification decisions. In May 2005, U.S. Strategic Command began developing joint performance measures.

Status Legend:

More Info
  • Review Pending-GAO has not yet assessed implementation status.
  • Open-Actions to satisfy the intent of the recommendation have not been taken or are being planned, or actions that partially satisfy the intent of the recommendation have been taken.
  • Closed-implemented-Actions that satisfy the intent of the recommendation have been taken.
  • Closed-not implemented-While the intent of the recommendation has not been satisfied, time or circumstances have rendered the recommendation invalid.
    • Review Pending
    • Open
    • Closed - implemented
    • Closed - not implemented

    Recommendations for Executive Action

    Recommendation: To address the challenges emerging in joint operations, the Secretary of Defense should direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to develop or adjust communications interoperability standards and electromagnetic frequency reprogramming capabilities standards and ensure that they are applied to new or modified unmanned aircraft, sensor and communications payloads, ground stations, and related equipment.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In our December 2005 report, we reported that the military services had experienced bandwidth capacity constraints in unmanned aircraft systems (UAS) operations, limiting both the number of UAS and other systems that can be operated simultaneously and the amount of data that can be transmitted from the unmanned aircraft communications payload. One reason for this constraint was the large number of unmanned aircraft that relied solely on the C-band of the electromagnetic spectrum for their data transmission capability. We reported the problem could not be easily overcome without potentially costly modifications to existing systems because the Department of Defense (DOD) had not required unmanned aircraft or sensor payloads to be reprogrammable from one band to another and therefore had not established standards. As a result, most unmanned aircraft had been designed and built without the flexibility to operate in differing frequencies or bands to avoid congested frequencies. GAO recommended that DOD develop or adjust communications interoperability standards and electromagnetic frequency programming capabilities standards and ensure they are applied to new or modified unmanned aircraft, sensor and communications payloads, ground stations, and related equipment. DOD directed the military services to operate in common frequency spectra and specified a Common Data Link baseline for all tactical and larger unmanned aircraft in accordance with the revised Common Datalink specification. The DOD Common Datalink policy became effective December 30, 2005 and the UAS Spectrum Regulatory Guidance became effective April 14, 2006. The directives assigned threshold frequency bands for tactical and larger UAS and standardized data link waveforms to enhance interoperability within DOD networks and systems.

    Recommendation: To address the challenges emerging in joint operations, the Secretary of Defense should direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to develop sensor and other payload commonality standards where practical and enforce such standards when modifying existing unmanned aircraft or payloads and developing new ones.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In our report, we found that some sensor payloads cannot be interchangeably used on different unmanned aircraft systems (UAS) because DOD has not adopted a payload commonality standard and that some UAS missions may have to be delayed if compatible unmanned aircraft and payloads are not available. Therefore, we recommended that the Secretary of Defense direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to develop sensor and other payload commonality standards where practical and enforce such standards when modifying existing unmanned aircraft or payloads and developing new ones. For completed actions in response to this recommendation, DOD stated that efficiencies and savings from developing, producing, and sustaining "common payloads" for integration into different unmanned aircraft types is encouraged and where practical, the services work together to acquire common payloads. Specifically, in May 2008, DOD directed the Air Force Predator program and the Army's ER/MP Sky Warrior program to develop common electrooptic/ infra-red (EO/IR) sensor payloads and the Air Force and the Army have developed a common sensor payload for these UAS. As a result, these UAS programs will have common sensor payloads which could allow the payloads to be used interchangeably on the unmanned aircraft.

    Recommendation: To address the challenges emerging in joint operations, the Secretary of Defense should direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to develop appropriately detailed UAS interoperability standards.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In our December 2005 report, we reported that while the Department of Defense (DOD) acknowledged the need to improve unmanned aircraft systems (UAS) interoperability that undermined unmanned aircraft operations, little progress had been made. We reported that a 2001 GAO report found interoperability problems due to the military services' continued practice of acquiring systems to support their own operations but not necessarily that of the other services. In part, interoperability remained a challenge because DOD had not always adopted new or enforced existing standards that might have prevented or mitigated some communications interoperability problems. As a result, while DOD had issued a directive, instructions, guidance, and roadmaps, and established at least five different organizations to promote UAS interoperability, no organization had or exercised sufficient authority to enforce program direction, or to ensure that the standards and guidance are in concurrence. GAO recommended DOD develop appropriately detailed UAS interoperability standards. In September 2007, the Deputy Secretary of Defense directed the Under Secretary of Defense for Acquisition, Logistics, and Technology, in coordination with the Chairman of the Joint Chiefs of Staff, to develop UAS interoperability profiles for incorporation into the Joint Capabilities Integration Development System. In June 2008, DOD published an Unmanned Systems Interoperability Profile for line-of-sight transmission of motion imagery for battle space awareness using the standard common data link. The profile defines the mandatory implementation of standards and specifications to achieve an interoperable internal and external information exchange and is the minimum threshold implementation for UAS. The Unmanned Systems Interoperability Profile applies to all developmental and fielded Tier 2 and above UAS as defined by the Joint UAS Concept of Operations and pertains to the direct communication and receipt of data from the air vehicle to the control station or remote video terminal. As a result of DOD's implementation of our recommendation, communications interoperability of unmanned aircraft will be enhanced.

    Recommendation: To address the challenges emerging in joint operations, the Secretary of Defense should direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to determine whether unmanned aircraft need all-weather flying capabilities, identify any performance degradation associated with all-weather flying capabilities, and obtain all-weather capabilities where appropriate.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In our report, we found that unmanned aircraft are more likely to be grounded in inclement weather than manned aircraft due in part to their lighter weight. Further, at that time, DOD had neither required all-weather capability nor evaluated the performance trade-off that may arise from developing it even though it established all-weather capability as a goal in the 2002 Roadmap. Therefore, we recommended that the Secretary of Defense direct the Undersecretary of Defense (Acquisition, Technology, and Logistics), the Chairman of the Joint Chiefs of Staff, the service secretaries, and other appropriate organizations to work together to determine whether unmanned aircraft need all-weather flying capabilities, identify any performance degradation associated with all-weather flying capabilities, and obtain all-weather capabilities where appropriate. For completed actions in response to this recommendation, DOD stated that the services evaluate their weather capability requirements for each of their unmanned aerial systems (UAS) and develop and acquire these capabilities where appropriate. In December 2008, the Joint Requirements Oversight Council Chairman highlighted the need to continue efforts on all-weather capabilities on all variants of unmanned aerial systems. For example, the Navy's Broad Area Maritime Surveillance UAS and the Army's Extended Range/Multi-Purpose UAS have anti-ice and de-icing capabilities within the approved requirements documents. Additionally, the Navy determined the performance degradation to the Broad Area Maritime Surveillance UAS as a result of adding these capabilities. As a result, these UAS programs are less likely to be grounded due to inclement weather and the Navy understood the trade-off between the added capability and some degraded performance.

    Recommendation: To improve joint operational performance reporting, the Secretary of Defense should direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum measures how effectively UAS perform their missions by identifying quantifiable goals and comparing results with desired outcomes.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In this report (GAO-06-49)and in again in "Unmanned Aircraft Systems: Advance Coordination and Increased Visibility Needed to Optimize Capabilities" (GAO-07-836), we reported that DOD was unable to fully evaluate the performance of its ISR assets because it lacked a complete set of metrics and did not consistently receive feedback to ensure the warfighter's needs were met. In December 2005 we recommended that DOD ensure its performance measurement system at a minimum measures how effectively UAS perform by identifying quantifiable goals comparing results with desired outcomes. In July 2007, we further recommended that the Secretary of Defense develop a process for systematically capturing feedback from intelligence and operations communities to assess how effective intelligence, surveillance and reconnaissance assets, such as UAS, are in meeting warfighters' requirements. In response to this recommendation, in January 2009, DOD integrated in its Intelligence Assessment Tool post-mission summaries enabling the ISR Assessment Tool to track metrics such as number of targets planned and collected and number of hours flown per UAS missions. Additionally, the tool allows users to determine the operational effects for specific missions and provides data on which missions ISR platforms are used to support and what the outcome of those missions were. As a result, DOD's ability to evaluate the performance of its ISR missions is improved.

    Recommendation: To improve joint operational performance reporting, the Secretary of Defense should direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum identifies the specific performance indicator information that needs to be collected to adequately assess joint performance.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: In our report, we found that although some missions effectively supported joint missions, the Department of Defense (DOD) had incomplete information on joint unmanned aircraft system (UAS) operations. Therefore, to improve joint UAS operational performance reporting, we recommended in December 2005 that the Secretary of Defense direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum identifies the specific performance indicator information that needs to be collected to adequately assess joint UAS performance. In response to this recommendation, DOD stated that the U.S. Strategic Command's Joint Functional Component Command for Intelligence, Reconnaissance, and Surveillance (ISR), in coordination with the services and combat support agencies, develops metrics and measures of effectiveness to determine the department's ability to meet ISR requirements to satisfy combatant commander requirements. In late 2008, the U.S. Joint Forces Command Joint UAS Center of Excellence was the office tasked to develop Joint UAS operational measures of effectiveness. As such, in June 2009, the Center issued a report on UAS full motion video measures of effectiveness, which identified specific performance indicators to optimize joint UAS employment for operations. As a result, DOD has identified indicators to better inform commanders and other decisionmakers about UAS performance in joint operations.

    Recommendation: To improve joint operational performance reporting, the Secretary of Defense should direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum develops indicators that assess communications and payload interoperability, and the extent to which electromagnetic spectrum congestion is undermining joint operations.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: DOD has identified performance measures for unmanned aircraft systems that will improve joint operational performance reporting and has developed the institutional momentum needed to continually improve its performance management. This action meets the intent of our recommendation.

    Recommendation: To improve joint operational performance reporting, the Secretary of Defense should direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum establishes baselines and applies the identified indicators against the baselines to gauge success in joint UAS performance.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: DOD has identified performance measures for unmanned aircraft systems that will improve joint operational performance reporting and has developed the institutional momentum needed to continually improve its performance management. This action meets the intent of our recommendation.

    Recommendation: To improve joint operational performance reporting, the Secretary of Defense should direct the Commander of the U.S. Strategic Command to ensure that the performance measurement system being developed by the command at a minimum develops a way to systematically collect identified performance information and routinely reports it to organizations that develop and field UAS.

    Agency Affected: Department of Defense

    Status: Closed - Implemented

    Comments: DOD has identified performance measures for unmanned aircraft systems that will improve joint operational performance reporting and has developed the institutional momentum needed to continually improve its performance management. This action meets the intent of our recommendation.

    Apr 16, 2014

    Apr 11, 2014

    Apr 10, 2014

    Apr 9, 2014

    Apr 8, 2014

    Apr 3, 2014

    Apr 2, 2014

    Looking for more? Browse all our products here