Transport
Discover facts about transport. Small discoveries that change the way you see familiar things.
Transport
Standard tractor-trailers have 18 wheels
The tractor contributes ten wheels: two up front and eight on its drive axles. The trailer adds eight more. Those paired tires spread the load and give the…
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A unicycle stays upright through constant small corrections
The rider changes pedal pressure and body position to keep the wheel beneath their balance. A standard unicycle has no second wheel to create the stable…
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When one arm stops swinging as you walk
Your arms swing opposite your legs to counter the twist each step sends through your torso. Hold one arm still and your body has to work harder to stay…
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Victorians feared trains would melt their bodies
A train turned speed into a new bodily worry: people had little experience with rapid travel, and some Victorian commentators feared the motion and rushing…
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Paris once endured a 109-mile traffic jam
Holiday traffic and bad weather packed the road between Lyon and Paris until cars stretched bumper to bumper for 109 miles. Once one slow patch forced drivers…
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Why airplanes have swept-back wings
At high speed, air over a straight wing starts to create a sharp rise in drag near the speed of sound. Sweeping the wings back reduces how directly the…
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Unicycle saddles feature heavily curved designs
A unicycle rider steers and balances with their legs, so a wide, flat saddle would get in the way. The curved shape gives the thighs room to move while…
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Why road crews need so many cones
Cones give drivers a visible, gradual path around a work zone instead of a sudden surprise at the edge of a lane. A long taper buys people time to slow down…
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Luxury sport utility vehicles contain separate climate zones
Separate vents and controls let the front seats and rear seats choose different temperatures. The system mixes warm and cool air for each zone instead of…
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How bicycles save millions of gallons of gas
Every car trip replaced by a bike ride leaves gasoline in the tank instead of burning it on the road. Multiply that swap across millions of riders and the…
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The Red Baron painted his plane bright red
Richthofen painted his aircraft red, turning it into a signature opponents and fellow pilots could spot at a glance. The color helped build the identity…
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Why ordinary helicopters can't rescue climbers on Everest
At Everest’s height, thin air gives a helicopter’s rotors less to bite into and its engine less oxygen to work with. Hovering needs extra lift, especially…
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How fighter jets refuel in midair
A tanker trails a fuel hose ending in a drogue, a basket-shaped target. The fighter pilot guides a probe into it, then fuel flows between the aircraft; at…
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Gravity painfully dragging dirt down hillsides
A hillside holds soil in place through friction and tangled roots. Gravity keeps pulling downhill; when water loosens the soil or a slope gets too steep, that…
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Why hearses can be stretched-out station wagons
A hearse needs a long, low cargo space, and a station wagon already has one. Stretch the chassis, add room for the coffin, and the family car becomes a…
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Some London escalators slow down when nobody is riding
TfL's eco-mode machines drop to half speed after a quiet interval, then respond when a passenger approaches. In 2023, the agency estimated overall energy…
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When wealthy passengers brought their beds on trains
Before comfortable sleeper cars were standard, a long rail journey meant trying to sleep on a hard seat. Wealthy passengers brought bedding to make a berth of…
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Yield signs mean nobody stops unless physically forced
A yield sign gives priority to other traffic; the driver slows and stops only when the crossing is occupied. The idea is to keep cars moving through a clear…
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Why anyone would ride a unicycle through the mountains
A mountain unicycle has one narrow wheel to thread between rocks and roots, while the rider shifts weight to steer and brake. No frame to snag on the…
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A flare gives a heat-seeking missile a false target
Defensive flares create a strong infrared signal away from an aircraft, attempting to draw a heat-seeking threat off its path. The idea is not to hide all the…
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The US Navy sent huge naval guns to France by rail
During World War I, five 14-inch naval guns were mounted for railway service on land. Rail transport let crews move weapons far too heavy for ordinary field…
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Why hot-air balloon burners sound like flamethrowers
A balloon burner sends pressurized propane through jets, where it mixes with air and ignites in a fierce roar. That blast heats the air inside the envelope;…
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The Beetle used its spare tire to wash the windshield
The Beetle used compressed air from its spare tire to push washer fluid onto the windshield. No electric pump needed: the tire did double duty as emergency…
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Why escalator handrails never quite match the steps
The steps and handrail run on separate loops, and the rubber rail stretches and wears as it travels. That tiny difference lets your hand drift ahead of—or lag…
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