Design
The 737's main landing gear under the wings at mid-cabin rotate into wells in the aircraft's belly; the legs being covered by partial doors, and "brush-like" seals aerodynamically smooth (or "fair") the wheels in the wells. The sides of the tires are exposed to the air in flight. "Hub caps" complete the aerodynamic profile of the wheels. It is forbidden to operate without the caps, because they are linked to the ground speed sensor that interfaces with the anti-skid brake system. The dark circles of the tires are clearly visible when a 737 takes off, or is at low altitude.
737s are not equipped with fuel dump systems. The original aircraft were too small to require them, and adding a fuel dump system to the later, larger variants would have incurred a large weight penalty. Boeing instead demonstrated an "equivalent level of safety". Depending upon the nature of the emergency, 737s either circle to burn off fuel or land overweight. If the latter is the case, the aircraft is inspected by maintenance personnel for damage and then returned to service if none is found.
Read more about this topic: Boeing 737
Famous quotes containing the word design:
“What but design of darkness to appall?—
If design govern in a thing so small.”
—Robert Frost (1874–1963)
“You can make as good a design out of an American turkey as a Japanese out of his native stork.”
—For the State of Illinois, U.S. public relief program (1935-1943)
“To nourish children and raise them against odds is in any time, any place, more valuable than to fix bolts in cars or design nuclear weapons.”
—Marilyn French (20th century)