Technology Flies High on Boeing 737

Imagine waiting in the terminal for your flight to depart San Francisco International Airport when suddenly, a thick blanket of fog rolls down from the bay and envelops the airport. Visibility is cut to 300 feet (91 meters). The word “delayed” starts to scroll across departure monitors. Your flight on a Boeing Next-Generation 737, however, leaves on time, thanks to state-of-the-art flight deck technology.

At a time when increased security screenings lengthen the time it takes to travel, The Boeing Company continues to develop new technologies that promise to reduce flight delays and enhance safety and flight-crew efficiency. Nowhere is that more apparent than on the Next-Generation 737.

The airplane is the most popular commercial jetliner ever built. More than 4,000 737s have carried about 7 billion people—more than the equivalent of the world`s population. In fact, every 5.3 seconds a 737 takes off or lands somewhere in the world.

The newest members of the 737 family—the 737-600/-700/-800/-900 models—entered into service just five years ago after a technology makeover. The digitally designed 737s are outfitted with larger wings and more powerful engines, which allow them to fly higher, faster and farther than previous models and its competitor. In addition, the new flight deck features advanced programmable software and liquid-crystal flat-panel displays, not available on competing models.

An example of the 737`s leading-edge technology is a sophisticated system called Head-up Display or HUD. Although HUD has been used on military aircraft for several years, the 737 is the only large commercial jetliner produced today with this capability.


HUD uses a transparent glass display positioned between the pilot`s eye and the flight deck window to show critical information such as airspeed, altitude, attitude and flight path. During takeoffs and landings, an image of the runway is superimposed over the actual view out the window.

The technology can eliminate flight cancellations, diversions and delays caused by restricted visibility. It also provides an extra margin of safety by allowing a pilot to keep his or her eye “on the road,” rather than looking down at the instrument panels. The ability to present data in real-world context makes it easier for pilots to take in information and fly the airplane, according to 737 Chief Pilot Ray Craig.

“As a pilot, it can be somewhat difficult to land at an airport at night or during low-visibility conditions with a high workload,” Craig said. “Without having to do any extra calculations, I have all the important data I need to fly an approach under those conditions. That allows me to focus on landing the airplane safely.”

This extra margin of safety allows a HUD-equipped airplane to fly when others cannot. Some regulatory standards require a minimum of 600 feet (182 meters) of visibility before an airplane is allowed to takeoff. Airplanes with HUD can takeoff in visibility conditions as low as 300 feet (91 meters).

Alaska Airlines was the first to incorporate HUD across its Next-Generation 737 fleet.

“We fly into many destinations where fog, reduced visibility and strong winds combine to restrict our system schedule,” said Captain Paul A. Majer, Alaska Airlines System chief pilot. “The HUD technology enhances our capability to depart an airport with reduced visibility and helps us get our passengers to their destinations as scheduled. HUD has been a tremendous benefit to safety overall and, specifically, our ability to operate safely despite reduced visibility conditions.”

Another advancement in the flight deck is Vertical Situation Display (VSD). This high-tech marvel builds on the Enhanced Ground Proximity Warning system and gives pilots a clear view of the airplane`s current and predicted flight path.

The ability to see the predicted flight path provides an earlier warning of conflicts with terrain or an overshoot of the runway. The same data exists in flight decks today, but the pilot needs to mentally integrate the data from several sources. VSD does this automatically and instantaneously.

The system constantly monitors the airplane`s flight path, calculating the airplane`s altitude, speed and position, and portrays the information in an integrated and easily understood graphical display. Traditional flight deck displays give pilots a bird`s-eye view of an airplane`s position relative to the rest of the world.
“VSD gives the pilot a side view of the world, because people think in those terms. It adds a normal perspective for a pilot and increases situational awareness,” said Ken Hiebert, Boeing Product Marketing regional director.
Earlier this year, Australian carrier Virgin Blue became the first airline to use VSD.
“The Next-Generation 737 is one of the best, if not THE best aircraft in the world in terms of technology,” said Capt. Steve Knudsen, Virgin Blue`s Flight Operations technical manager. “The new Vertical Situation Display provides pilots with yet another tool to monitor the aircraft`s flight path. It is a valuable safety enhancement.”

But predicting the flight path is not just important for avoiding mountaintops. VSD can provide an assurance that the airplane will be at a certain point in space at a certain point in time. That degree of accuracy can help rewrite air traffic rules and increase air space capacity, something that is desperately needed in crowded skies over Europe, the United States and other parts of the world.
In today`s air traffic system, airplanes approaching airports tend to stack up in the sky, waiting to get to the gate. It`s similar to cars slowing down as they approach a traffic light. If cars have to start slowing down two blocks away, traffic slows to a crawl. Essentially, the same thing happens in the sky. Because today`s system can`t ensure an airplane`s precise position, air traffic controllers require a certain amount of time and distance between airplanes. VSD can change all that.
“VSD should enable us to shrink the air space between airplanes and increase air space capacity because you can count on airplanes being exactly where they are supposed to be. And if we can move airplanes through air space more efficiently, we can add more flights and passengers will have more choices,” Craig said.