Most long-haul passengers want to sleep but experience the economy class as uncomfortable. This study explores dimensions of beds and using flat beds in economy class by using the space of four seats and replace these with stacked beds. While feasible, key challenges include safety during taxi, take-off and landing, comfort while using devices, and difficulty getting into the beds. A pilot test with a low fidelity prototype showed that passengers could access the beds, but privacy and space issues are more an issue. The study concludes that, besides seat and bed design, sleep quality also depends on recline angle, temperature, noise, and lighting—factors that airlines should consider.