A novel approach for the electrochemical oxidation of coal is described. The electrochemical cell employed an anode of coal or carbon particles dispersed in a molten carbonate electrolyte at 500°–800°C. At these temperatures, the oxidation kinetics of coal/carbon are sufficiently rapid that high current densities can be obtained at an inert working electrode. Results presented for various forms and concentrations of carbon include open‐circuit potentials, current‐voltage curves, and product gas evolution rates. At temperatures of 700°C and above, the measured potentials were in agreement with theoretical values of the C/CO2 redox couple. Product gas analysis indicated that complete oxidation of carbon to CO2 was achieved, thus providing the maximum electrochemical conversion efficiency (four electrons per carbon atom). By coupling this anode with an O2/CO2 cathode, fuel cell operation (i.e., electricity generation) should be feasible. The primary limitation observed in this study was the heavy chemical consumption of carbon by CO2 , which resulted in a low overall carbon conversion efficiency.

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This paper is one of two in a dual abstract submission to AIAA Aviation 2016, "Air Transportation Integration and Operations -Unique and/or transformational Flight Systems"and details the design, construction, testing and results of a team-devised package pickup system and CG relocation apparatus. Said technology was created in parallel with a tailsitter vehicle, Proteus, whose design, construction and testing are outlined in the companion paper, "An Unmanned VTOL and Fixed Wing Package Retrieval and Delivery Vehicle" [1]. Note that all technology outlined in this paper may be integrated into various vehicle configurations, not just Proteus. The vehicle itself and subsequent technology are the culmination of a project assigned to the 2015 NASA Multidisciplinary Aeronautics Research Team Initiative (MARTI) at Langley Research Center. MARTI was tasked with developing an unmanned vertical takeoff and landing (VTOL) vehicle for the purpose of package identification, pickup and delivery. From conception to completion, the team had 12 weeks. To meet these and other requirements, MARTI constructed a dual-functioning, tail-sitting aircraft, named Proteus, which is capable of transition from traditional quadrotor mode to fixed wing design for drag-efficient forward flight. Consult "An Unmanned VTOL and Fixed Wing Package Retrieval and Delivery Vehicle" for additional vehicle details, as such information will only be referenced in support of the topics discussed in this paper [1].

This paper presents an overview of methods to determine the state-of-health of maintenance-free aircraft batteries. The various failure modes of aircraft batteries are discussed, along with methods of detecting failed batteries.