To land an airship that is 250 pounds heavy in calm wind, what landing attitude is best?

Landing an airship requires careful consideration of its weight distribution and stability. For a landable approach, a tail-heavy attitude—around 20 degrees—is beneficial because it allows for better control during the descent and landing phase.

When an airship is slightly tail-heavy, it helps maintain a more stable descent as the tail can create a natural stability that counters any potential nose-over tendency. This attitude also aids in managing the airship's lift as it approaches the ground, preventing a sudden loss of lift that could lead to a hard landing.

Other attitudes may compromise the stability and control during landing. A level flight attitude can be too neutral and might not provide the necessary stability in descent, while a tail-light attitude could lead to increased risk of an uncontrolled descent or sudden lift loss. The neutral position, while seemingly balanced, may not have enough rearward control to manage the weight effectively during landing. Thus, a tail-heavy approach offers the best combination of stability and control for landing an airship of that weight in calm conditions.