What should an airship do if both engines fail while en route?

In the event of both engines failing during flight, the airship must prioritize safety while managing its descent. The correct response is to achieve a condition of equilibrium quickly, allowing the airship to enter a free-balloons state. This means allowing the airship to stabilize and use its buoyancy effectively.

When an airship is in free-ballooning mode, it can utilize the lift generated by the lighter-than-air gas (like helium or hydrogen) contained within its envelope. This controlled transition helps manage altitude and descent rates safely, rather than risking uncontrolled descent or rapid altitude loss due to other reactions. The airship can then assess the situation, maintain stability, and plan for landing choices based on current conditions.

Options that suggest increasing speed to gain altitude could lead to more complications under engine failure, as it's impractical and dangerous to attempt to ascend without power. Maintaining current altitude while waiting for assistance does not address the critical need for immediate descent management in an emergency. Lastly, the idea of descending to the nearest airport overlooks the importance of stabilization and the nature of lighter-than-air craft, which operate quite differently from powered aircraft in emergency scenarios.