SEATTLE — You stagger off a long flight, feeling sticky, tired and dehydrated. You're still fuming at the flight attendant who abruptly turned on the cabin lights, awakening you from a moment's sleep.

Picture this instead: Starting in 2008, major aircraft makers say, the newest planes will feature fresher air, soothing lights and bigger windows. They're even talking about such amenities as showers and bunk beds, while admitting those are less likely to wind up in typical airliners.

Flying through the sky in a cramped tube may never be anyone's idea of heaven, but the world's biggest aircraft manufacturers are building jets that they claim will be more comfortable than ever, inaugurating an era of more tolerable air travel.

Veteran fliers have heard such sales pitches before. They've been promised amenities such as on-board luxury lounges, gyms and restaurants. The proposals often ran into major obstacles: The airlines weren't interested. Struggling to earn a profit, they have been cramming in more seats rather than adding amenities.

This time, however, rival aircraft manufacturers Boeing and Airbus say they've got it right. They're building jets that don't give the airlines a choice on many of the amenities, such as bigger windows, that passengers say they want most.

For the first time, Boeing is even limiting the type of seats airlines can choose to put in coach on its newest jet, forcing carriers to chose from an approved catalogue.

"We are trying to prevent the airlines from reducing the flying experience," said Kenneth Price, a marketing director at Boeing.

The improvements will appear first on Boeing's 787 Dreamliner, the first of which is scheduled to be delivered to customers in 2008. The Dreamliner cabin will be pressurized to a level typical of an elevation of 6,000 feet above sea level, Boeing says, compared with the current pressure, equivalent to an elevation of about 8,000 feet. Price says studies have shown that improving the cabin pressure significantly reduces headaches and other ailments.

Boeing also intends to make the Dreamliner cabin more humid, eliminating the bone-dry air that annoys many passengers. Together, higher pressure and more humidity should help temper the effects of jet lag, Boeing says.

The advancements will come from the use of composite materials to build the plane's fuselage. Boeing is using super-strong, lightweight composites to make the Dreamliner more fuel-efficient, an attractive feature for airline executives who have ordered 432 of the planes. But the company isn't shy about trumpeting the other benefits of composites: It's these stronger, more corrosion-resistant materials that will permit the higher cabin pressure and higher humidity.

"The physical environment, especially for the long-haul traveler, is going to be very different," Price said.

Boeing has patented a seating configuration to improve the chance that a passenger will end up next to an empty seat if the airplane is not fully booked. The Dreamliner will have a better air circulation and filtering system than on current planes, larger windows and a wider cabin, executives say.

Price said the improvements will not only be standard on the Dreamliner, but also are likely to be on next generation of Boeing aircraft.

Airbus will make many of the same features — such as better cabin pressure and humidity — standard on its A350 XWB, a competitor to the Dreamliner that could enter service by 2012.

Boeing is testing ways to use lights to give the appearance of more space on board. Melanie Kimsey, a Boeing design engineer, recently studied Las Vegas productions such as Cirque du Soleil to understand how its shows use lighting.

"We wanted to see what techniques and tricks they use and see if any of those can be scaled down to work on an airplane," Kimsey said.

Boeing and Airbus already offer airlines better lighting on some jets and plan to make such features standard on the Dreamliner and A350 XWB. The new lights won't be as harsh as current ones and will be easier to dim and brighten, the manufacturers say.

Airbus intends to take that idea a step further by offering the airlines the option of projecting images of the sky and nature on the ceiling of first- and business-class cabins of the A350 XWB, said Sophie Pendaries, director of payload accommodations at Airbus.

"When you are on an aircraft, you are in a small space compared to what is outside," Pendaries said. "We want to bring the space outside into the aircraft."