Material Assessment

-Question 1- Economic 1. Is hydrogen an expensive source of fuel? 2. What purity of hydrogen is required to run the engine? 3. What are the costs of hydrogen fuel compared to fossil fuel or battery power? 4. How many jobs will this project create? 5. What are the costs of materials for development of the airplane that can run off hydrogen fuel? 6. What is the impact of switching from refining fossil fuel to hydrogen production? Technical/Engineering 1. Research previously used methods of hydrogen storage and their effectiveness. 2. What is the weight ratio of fuel needed per pound (kilogram) of aircraft? 3. What are current technical barriers to this technology? 4. Will there be some kind of backup system, i.e. emergency battery power? 5. Where will the production site be? 6. What purity of hydrogen is required to run the engine? Safety 1. Will the vehicle be safe for the operator? 2. What are the concerns for storage of fuel cells or hydrogen tanks on aircraft? 3. What are the effects of additional weight on struts, wheels, wings, and shear forces? 4. What are the chances of leaks from the fuel cell to the engine of the plane? 5. Will there be fatigue effects from changes in temperature due to altitude differences? 6. Is there a way to isolate the cockpit from potential hazards such as fire or explosion? Environmental 1. Will a hydrogen fueled aircraft have any other byproducts besides water and CO2? 2. Does using hydrogen as an energy source affect the environment? 3. What is the net change in CO and CO2 production from changing from fossil to hydrogen fuel? 4. What regulatory agencies could we get to support or fund the project? 5. Are there any environmental concerns that would induce regulations by environmental groups? 6. What kind of disposal procedures are required for expired fuel cells? Health 1. Will the presence of flammable hydrogen be a large risk factor to people working at the production site? 2. What safety precautions will be implemented to avoid hydrogen gas-related fires? 3. How will the hydrogen be stored during development? 4. How will the hydrogen fuel be stored onboard the aircraft? 5. What changes would be required in the exhaust system to expel the combustion products? 6. Will any special protection equipment be needed in operating the aircraft? 7. Does current health insurance cover pilots or operators of such an aircraft? Legal 1. What existing or developing patents will we have to deal with? 2. Will this aircraft or any of its components need to go through the patent process itself? 3. We must not be liable for injuries sustained on the worksite or while testing the aircraft off post. 4. Do any laws act as barriers for operation or development for the aircraft? 5. What are FAA regulations concerning experimental aircraft? 6. Can the plane be flown in regular airspace? Societal Impact 1. How loud will a hydrogen fuel-powered aircraft be? 2. What is the general public reaction to a hydrogen powered aircraft? 3. Will special interest groups (ex EPA) be interested in this project? Would they possibly promote the efforts? 4. Will this increase land values near airports? 5. What is the potential for job creation? 6. Will the local community feel safe with such experimental aircraft in the area? 7. Are there any reasons people would be against this project? Regulatory 1. What safety regulations do we need to be aware of with regard to developing the aircraft? 2. What are the restrictions on flying test vehicles? 3. Where are we allowed to fly the experimental vehicle? 4. What is the process for obtaining FAA approval to operate? 5. Are there EPA regulations with regard to having hydrogen fuel cell components (metal hydrides) in the atmosphere? 6. Are there passenger restrictions concerning operation of experimental aircraft? Quality 1. How reliable will the aircraft be? 2. How frequently do hydrogen cells fail? 3. How often do hydrogen cells need to be replaced/recharged? 4. How will the presence of hydrogen fuel cells affect the amount or frequency of maintenance on the aircraft? 5. Are there mechanics available that have the knowledge or experience to work with fuel cell technology? 6. What kind of tests will we run to assure the safety and performance of the vehicle? -Question 2- Structural – Storage Container 1. A. An impact could cause the container to rupture. o acute o dynamic o compressive B. Fracture would be the chief failure mechanism because it is caused by a sudden impact. C. Have a hard, strong outer casing for the tank covered by an elastomer coating. 2. A. Stored fuel causes a breakdown of the metal hydride fuel cell. o chronic o static o combination of shear, tension, and compression (due to material breakdown or dissolving) B. Fatigue due to corrosion from dissolving. C. Further research and development of metal hydrides and fuel cell storage technology. Delivery System 1. A. Fuel lines could break due to a pressure rupture. o acute o dynamic o compressive B. Fracture would be the failure mechanism due to sudden high pressure surge puncturing the fuel lines. C. Include lines made of material that are highly flexible (elastic) and can withstand high pressure. 2. A. Fuel lines could have a slow leak. o chronic o static o Combination of tension and compression due to temperature variations. B. Creep and fatigue would both contribute to the failure of the system. Creep will occur near the high temperature engine compartment. Cryogenic embrittlement could occur near the delivery of liquid hydrogen. C. Insulate the lines near extreme temperature conditions. Engine Compartment 1. A. Engine failure due to discrepancies in combustion temperature and pressure. o chronic o dynamic o combination of shear, tension, and compression on engine’s internal, rotating assembly and internal components. B.Cyclic fatigue with engine operation due to normal, continuous cycling of pistons and increased wear on engine components due to increased combustion temperature and pressures from hydrogen fuel ignition. C. Experimentation with both engine components and combustion processes (engine tuning). Through measurement of combustion temperatures and pressures, appropriate metal alloys can be selected to withstand potential increased fatigue and creep.