I used to think that the planes are in the air most of the time in order to minimize the time they are on the ground not generating revenue.

When I was onboard a 744 from HKG-LHR I started thinking about what routes actually had the new club beds and at that time, only JFK/SFO/HKG. The normal flight schedule for HKG-LHR is to leave late at night and arrive in London the next morning around 5-6am. Now the next scheduled flights from LHR back to HKG is not until the afternoon and evening. Does the plane sit on the ground for the whole day? The plane cannot really be used for other routes because it has the new beds.