With the continued rise in wildfires in California, and around the world, technological advancements are needed to improve the safety and effectiveness of wildland firefighters. One area that provides an opportunity for such development is the deployment of temporary communications networks. Currently, radio repeaters are set up on mountain tops in the response area; such repeaters do not provide flexibility once installed, still have blind spots, and require the time of valuable assets like helicopters to install. This thesis will establish the feasibility of airborne radio repeaters for wildland firefighting. In order to successfully demonstrate the feasibility of such an airborne system, the resulting system should be rapidly deployable, improve communications range and reliability, and be compatible with existing regulations and guidelines. The design process for the repeater payload is described, as well as important troubleshooting steps. The resulting product is then compared to the initial requirements through testing and observation. Although audio filtering provided by off-the-shelf handheld radios prevented the repeater from functioning as intended, the proposed 2m/70cm dual-band digital communications relay was capable of being carried by the Altavian Nova and was able to successfully demonstrate the feasibility of such a system. As such it will be an important contribution to communications needed for fighting future wildfires.

The current uses of unmanned aerial vehicles (UAVs) in wildland firefighting center around mapping, scouting, and firing operations. These operations and additional operations are often held back by lack of range and lift capacity of current UAV options. Software design tools were developed in this research to aid in designing a UAV for wildland firefighting. The tools help create a mission profile, estimate the mass of the UAV, select a motor and rotor, select a battery, and generate and analyze a finite element (FE) sector model. These tools leverage parametric analysis and studying existing hardware to create a design. The FE model is generated based on the mission profile, a motor and rotor, and battery as design parameters and a set of design variables. The tools developed for creating a mission profile, estimating mass, selecting a motor and rotor, and selecting a battery successfully aid the preliminary design of an octocopter, hexacopter, and quadcopter. The FE tool was designed around an octocopter's geometry, which leads to complications in generating FE models for a hexacopter or quadcopter. Recommendations were made for altering the FE tool to account for hexacopters and quadcopters. Other recommendations were made to support future work in creating an optimized design of a wildland firefighting UAV. / Master of Science / The use of multirotor UAVs in various industries is rapidly expanding. One industry that currently uses UAVs but is limited in their capabilities is wildland firefighting. Wildland firefighters use UAVs for scouting, mapping, and firing operations. Scouting includes finding road access to the fire, finding water sources, searching for spot fires, and many other applications. Mapping is typically done to understand the size of the fire. Firing operations are conducted to start small, controlled fires to remove fuel from the fires path. However, these operations as well as future applications of UAVs are often limited by the flight time and the lifting capabilities current UAV options offer. Tools were developed in this research to create a preliminary design of a UAV for wildland firefighting. The design parameters and variables of the UAV design are outlined throughout the tools. The tools allow for compiling mission requirements, selecting motors/rotors and a battery to use in the UAV, and a preliminary structural analysis of the UAV design. The preliminary structural analysis includes extracting stresses, strains, and displacements experienced through a simplified mission as well as the natural frequencies of the finite element sector model. The design of octocopters, hexacopters, and quadcopters were explored using the set of design tools. The tools were successfully in selecting components for each style of UAV and at the preliminary structural analysis of the octocopter design. However, the structural analysis was not able to be conducted for the hexacopter and quadcopter design due to geometric conditions in the finite element model.