We are going to produce a complete design for a cargo airship. The requirements are that it should be able to carry at least 500 metric tons of cargo at least 12,000 km at least 90 km/h in 15 km/h headwinds. It should be fully lighter than air, have rigid structure, and use hydrogen lifting gas. What is the first step? | The first step in designing a cargo airship with these specifications is to conduct a preliminary sizing analysis. This will help determine the approximate dimensions and volume of the airship needed to meet the cargo capacity and range requirements. Here's how to approach this initial step:
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Calculate the required lifting gas volume:
- Determine the total mass that needs to be lifted (cargo + airship structure + fuel + crew + equipment)
- Calculate the lifting force of hydrogen at the operating altitude
- Estimate the volume of hydrogen needed to provide sufficient lift
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Estimate the aerodynamic characteristics:
- Determine the rough shape and dimensions of the airship
- Estimate the drag coefficient based on the shape
- Calculate the power required to maintain the specified cruise speed in given wind conditions
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Perform an initial weight estimation:
- Estimate the weight of the rigid structure
- Estimate the weight of propulsion systems, fuel, and other necessary equipment
- Ensure the total weight plus cargo capacity can be lifted by the calculated hydrogen volume
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Conduct a basic range analysis:
- Estimate fuel consumption based on the power required
- Calculate the fuel needed for the specified range
- Verify that the airship can carry enough fuel for the required range
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Iterate and refine:
- Adjust the initial estimates as needed to meet all requirements
- Balance between size, weight, and performance
This preliminary sizing analysis will provide a starting point for more detailed design work in subsequent steps. It's important to note that this process may require several iterations to find a feasible initial design that meets all the specified requirements. |