KC-130J HARVEST HAWK ALTERNATE LFT&E PROGRAM
By Raena Phillips and Les Bowman
The U.S. Marine Corps KC-130J Harvest Hercules Airborne Weapon Kit (designated Harvest HAWK) provides the KC-130J tactical refueller aircraft with multi-sensor imagery reconnaissance (MIR) and close air support (CAS) capabilities. When configured, the armed KC-130J (shown in Figure 1) includes the addition of weapon systems, facilities, and personnel to control those weapon systems. The Harvest HAWK mission system is a response to an urgent need of the Marine Corps to provide a roll-on, roll-off (RORO) system that quickly adds MIR and CAS capabili- ties to an existing airframe. Because of its RORO status, the Harvest HAWK system has no impact on airworthiness; however, by virtue of its added capabilities, there is a potential change in vulnerability. Thus, the Harvest HAWK is covered by U.S. Code, Title 10, Section 2366 as a product improvement program requiring incremental live fire test and evaluation (LFT&E) .
LFT&E FOR AN URGENT NEED
The focus of the Alternate LF T&E (ALF T&E) Test and Evaluation Test Plan/Strategy for Harvest HAWK was to meet the Title 10 require- ments at reasonable expense while providing valuable survivability information to both the Office of the Secretary of Defense (OSD) and the program office.
The Test Plan/Strategy was developed as a coordinated effort between test and evaluation personnel. The lead test and analysis engineers worked together to focus the ALF T&E on the added munitions systems and added crew as those additions would have the most impact in the change in vulnerability of the air vehicle. The ability to satisfy the Title 10 requirements through the ALF T&E Test Plan/Strategy, while maintaining a compressed timeline, was accomplished through leveraging the use of existing live fire (LF) and vulnerability data on similar systems.
Leveraging and Cooperation
The Harvest HAWK ALF T&E team maximized use of existing data sources by entering into a Memorandum of Agreement (MOA) between the U.S. Air Force and the U.S. Navy. This MOA provided the Navy with the Air Force C-130J vulnerability analysis, complete with input files, and allowed the Navy to build from existing C-130J analysis and test only the additional munitions systems. The MOA also benefited the Air Force, through a reciprocity provision, allowing the Air Force to leverage Harvest HAWK vulnerability analysis, test
plans, and reports for HC/MC-130J analysis.
ALFT&E TEST SERIES
Within the Harvest HAWK ALF T&E team, continuous cooperation was demonstrated through a truly integrated team. The Harvest HAWK ALF T&E was divided into three test series, each focusing on one of the added weapon systems. Each test series plan was authored by both a test and an analysis engineer. The test events were tailored to provide the maximum impact on the development of the vulnerability analysis inputs.
Early in the test planning phase, the test and analysis engineers noted appreciable data voids for each of the three weapon systems slated for testing. The decision was made to institute a phased test series for each weapon system. The phased approach maximized the limited budget and timeline by focusing on evaluating the Harvest HAWK’s vulnerability impact on the airframe and on its crew, maximizing the influence of LF data on the vulnerability analysis. This approach streamlined the process and strengthened both the test and analysis efforts.
The tested Harvest HAWK system configuration added MIR and CAS capability to the KC-130J airframe by adding three weapon systems and the means to control them. These weapon systems were the wing-mounted missiles deploying Hellfire munitions, the cargo
ramp-mounted standoff precision-guided munitions (SOPGM) deploying Griffin missiles, and a 30-mm gun system located out the aft paratrooper door (tested, but not fielded). Controlling these weapon systems is an added crewmember, the Fire Control Officer (FCO), who resides on the palletized fire control station (FCS), relying on inputs from the Harvest HAWK intelligence, surveillance, and recon- naissance (ISR) pod. The added systems and approximate locations are shown in Figure 2.
The incremental ALF T&E plan laid out in the KC-130J Harvest HAWK Test Plan/Strategy focused on the vulnerability associated with the weapon system additions. The crewmembers are inherently considered a system of the aircraft and were considered throughout both test and analysis. During the test series, simulator dummies were positioned at crewmember locations, and pressure and temperature data were collected to determine the effect on the crewmembers. Among the data obtained during the test events, analysis on the potential shielding provided to the crewmembers by the aircraft was considered and was documented in the survivability assessment report.
The wing-mounted munitions test series focused on the vulnerabilities associated with the addition of Hellfire missiles on outboard wing stations (Figure 3). The collaboration between the test and analysis engineers allowed the test series to be tailored to maximize the benefit for LF requirements while filling the data voids, thereby creating a more complete analysis.
The test series was split into component-level testing (Phase 1), which focused on the Hellfire’s energetic sections, the rocket motor and the warhead. Phase 1 pre-test predictions focused on expected component results based on historical LF data. A total of six shots were taken under Phase 1 testing, investigating the rocket motors’ and warheads’ response to impact by ballistic threats not previously considered under prior testing.
The second phase of testing (Phase 2) was full-up system-level (FUSL) testing. These tests addressed the potential synergistic or sympathetic effects at the system level, fulfilling the Title 10 requirements. Pre-test predictions for Phase 2 incrementally updated the vulnerability model based on Phase 1 post-test analysis. The post-test analysis for Phase 2 then updated the vulnerability model’s assumptions and methodologies to incorporate Phase 1 and Phase 2 data as well as historical insensitive munitions (IM) data.
Cargo Ramp-Mounted SOPGM
The cargo ramp-mounted SOPGM test series was also conducted in two phases. However, as the SOPGMs are internally carried (Figure
4), additional considerations for addressing crew survivability were made.
Ballistic impact of the internally stored energetic materials could induce an energetic reaction, producing smoke. Therefore, not only were crewmember locations equipped with pressure and temperature data recording devices, but the smoke was collected and analyzed for toxicity.
Phase 1 component testing investigated the reaction of the Griffin warhead and rocket motor to ballistic impact by the threats of interest. As nearly no prior testing had been conducted on the new Griffin weapon system, the pre-test predictions were based on historical data of similar systems without the benefit of existing IM data.
Post-test analysis of Phase 1 test events provided additional data for vulnerability modeling and pre-test predictions for Phase 2.
The test and analysis engineers devised shotlines that maximized penetration of threats, for Phase 2 testing. The shotlines also took into account shielding provided by aircraft structure. The use of these threats, velocities, and shotlines were consistent with the aircraft being fired at while in ascent from takeoff or descent to landing at a forward airfield.
Post-test analysis of Phase 2 then updated the assumptions and methodologies within the vulnerability assessment. Additionally, toxicology reports for the smoke collected, as well as temperature and pressure data for the crew, were analyzed to assess the vulnerability associated with the Griffin system to the KC-130J aircraft and the crew.
30-mm Gun System
The 30-mm gun system testing series focused on the ammunition associated with a gun system. The location of the ammunition canisters within the KC-130J’s cargo hold means that the crewmembers are not physically separated from the ammunition canisters.
While the proposed ammunition (Figure 5) itself has undergone IM testing, additional data were needed for the vulnerability assessment. Collaboration of the test and analysis teams resulted in another two-phased test series. Phase 1 predictions and testing focused on individual round reactions to ballistic impact, as a function of threat size, threat velocity, and impact location (e.g., primer, propellant, projectile, and fuze).
Phase 1 test data and historical IM test data were combined, creating an initial vulnerability model for the ammunition. Phase 2 testing pulled the pieces together, investigating the potential for synergistic or sympathetic effects of the ammunition system within the aircraft. As was performed for the SOPGM testing, a shotline analysis was conducted to maximize the penetration capabilities for the threats of interest for Phase 2.
Congruently with the wing and ramp munition test series, the criteria for selection of Phase 2 shots hinged on historical data available, Phase 1 test results, and shotline analysis. Criteria imposed by the team included that the threat chosen for Phase 2 testing was the smallest threat, at the lowest velocity, for which there was high confidence of producing the most severe reaction observed during Phase 1 testing.
Results of the phased tests were pooled along with historical data to create a vulnerability model of the new systems. The MOA reached with the Air Force meant that more time was devoted to creating and documenting the systems added as part of the Harvest HAWK. Building from the Air Force C-130J vulnerability data and focusing the test and analysis efforts on the added systems maximized the limited budget and scope of the ALF T&E. The vulnerability analysis conducted focused on the change in vulnerability associated with the addition of the Harvest HAWK systems, and therefore the change was documented as a change invulnerability increase over the baseline. The baseline for the vulnerability analysis took the Air Force C-130J vulnerability model and created the baseline KC-130J tanker model.
The incremental approach and focus on the change in vulnerability provided information regarding the vulnerabilities associated with the added mission capabilities, while also creating a set of government-owned vulnerability data for the KC-130J, as well as the Harvest HAWK system (Block E and Block F) upgrades.
Analysis and test personnel were included in all aspects of test planning, beginning with the Test Plan Strategy and extending throughout all subsequent test plans. This close relationship allowed for the identification of data voids in available historic data to be addressed in the test series. All three test series included a phased approach driven by the analysis team’s needs, with influence from test experience, to collect component-level data. As such, test plan details, including test matrices, shotlines, and instrumentation, were developed in a coordinated effort between experienced test and analysis personnel.
Pre-test predictions were provided by the analysis team prior to test execution, under the oversight of OSD. Pre-test predictions, while not required for the Phase 1 tests, were completed to complete the model-test-model cyclical approach. Phase 1 pre-test predictions built on any applicable historical data were used to identify data voids. Phase 1 test results were then analyzed post-test; and the combination of the historical data, predictions, results, and post-test analysis was fed into the design of and predictions for Phase 2 system-level testing. The Phase 2 results were then incorporated with Phase 1 and historical data into the vulnerability assessment.
This phased, highly coordinated approach maximized the limited budget and timeline, focusing the test series on evaluating the Harvest HAWK system’s vulnerability impact on the airframe, while also maximizing the influence of LF data on the vulnerability analysis. This approach was made possible by the coordination between the Harvest HAWK ALF T&E team, including the test engineers, analysts, and program office representatives.
Further, collaborating with the Air Force provided the program with a vulnerability dataset, the leveraging of which created a more complete analysis. Through the MOA with the Air Force, the Air Force’s HC/MC-130J analysis can then leverage the results and findings under the Harvest HAWK ALF T&E test and analysis. This approach streamlined the process, strengthened both the testing and the analysis efforts, and provided a valuable set of government-owned models for future use.
ABOUT THE AUTHORS
Raena Phillips has been with NAVAIR 418400D (Systems Engineering Department; Combat Survivability Division; Survivability Assessment Branch) for approximately 5 years. She has supported Navy and Marine Corps vulnerability analyses, as well as Joint Aircraft Survivability Program Office (JASPO) and Joint Technical Coordinating Group for Munitions Effectiveness (JTCG/ME) programs.
Les Bowman has been with NAVAIR 418300D (Systems Engineering Department; Combat Survivability Division; Vulnerability Branch) for approximately 5 years. Previously, he worked for the Navy for 34+ years. He has served as a test engineer and as the head of fire science working on fire suppression, and he has performed engine research and development.
 U.S. Code, Title 10, Section 2366.