Peak demand can vary greatly based on the number of simultaneous water uses, the flow rates of individual water fixtures, and the length of time fixtures operate. 5 gpm (two fixtures running simultaneously at 2.5 gpm) is a good estimate of peak demand, for the typical household. Water wells that reliably yield 5 gpm should be able to meet peak and daily needs for most residences. Wells yielding less than 5 gpm, however, are sometimes the only water source available.
Lifeboat may refer to: Lifeboat (shipboard), a small craft aboard a ship to allow for emergency escape. Lifeboat (rescue), a boat designed for sea rescues. Airborne lifeboat, an air-dropped boat used to save downed airmen.
An airship or dirigible is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from large gas bags filled with a lifting gas that is less dense than the surrounding air.