The quarterback who throws the most accurate passes isn't throwing perfectly. In fact, he can't.
Tom Brady has won seven Super Bowls and thrown more touchdown passes than any quarterback in history. But when researchers analyzed his throws in slow motion, they found something surprising: even Brady's tightest spirals wobble slightly. His long passes drift to the right. These aren't errors—they're fundamental features of how footballs fly.
To understand why, researchers ran computational fluid dynamics analysis, tested spinning balls in wind tunnels, and embedded sensors inside actual footballs. What they discovered challenges a centuries-old assumption about what makes a throw accurate—and reveals why the physics of throwing is far more complicated than it appears.
Why Spin Matters
A tight spiral isn't just about control. It's about survival in the air.
When a ball spins without angular momentum, it's unstable. Any minor disturbance—like a tiny bit of wind—causes more air to hit one side than the other. That imbalance deflects the ball further off course. As it tumbles sideways, the ball exposes nearly 70% more surface area to the oncoming air. Combined with a higher drag coefficient, this means an unspinning ball decelerates up to ten times faster than a spinning one.
This is why quarterbacks prioritize spin. A spinning football maintains its orientation, cutting through the air with a smaller frontal area and lower resistance. The angular momentum resists changes to its axis of rotation—just like a spinning top that stays upright when nudged.
The Historical Origin
The benefits of spin became clear in the mid-nineteenth century, during the Crimean War.
At that time, soldiers carried muskets firing round lead balls. These musket balls were made significantly smaller than the barrel, allowing faster reloading. But when gunpowder ignited, expanding gases escaped around the bullet, making its exit velocity unpredictable. Combined with inconsistent manufacturing and poor aerodynamics, muskets were unreliable.
Then, in fall 1854, everything changed at the siege of Sevastopol.
British troops set up on a distant hillside—far beyond standard musket range. The Russians weren't worried. Then, suddenly, windows shattered. British forces were shooting through barracks windows at nine hundred yards away using an entirely different projectile.
Eight years earlier, French army officer Claude Etien Minier had developed a conical bullet with a hollow base and an iron plug. When fired, gas pressure drove the plug into the base, expanding the bullet against the barrel walls so no gas could escape. This made muzzle velocity predictable. More importantly, the expanded bullet gripped spiral grooves carved inside the barrel—called rifling—which imparted spin.
The spin conserved angular momentum, helping bullets resist changes in orientation. Even if wind applied unbalanced force, the bullet maintained its path. The same principle applies to footballs today.
The Paradox
Here's where things get strange.
If angular momentum makes a ball hard to pivot, then on a long Hail Mary pass, it should stay pitched at the release angle the entire flight. But that's not what happens. When receivers catch Brady's long passes, they're angled differently than when he released them—often shifting from positive thirty degrees to negative thirty degrees in just four seconds.
This "turnover" is essential to an accurate throw because at every point along the arc, the ball's orientation stays closely aligned with its direction of motion. That minimizes drag.
You might think this works like arrows or birds—with front-weighted objects that align naturally due to heavier tips pushing ahead. But footballs are different. They have no feathers or fins, and their weight is evenly distributed along the axis. They can't use the same mechanisms.
So what makes them turn over? The answer remained unclear until very recently.
The Modern Research
In 2020, the editor-in-chief of the American Journal of Physics decided to figure it out. He was surprised by how many bad explanations had been published and accepted without scrutiny.
The researcher put together a theoretical model explaining football turnover—and his findings were tested in wind tunnels with Brady's actual throws. Sensors embedded in the balls revealed that Brady's maximum spin rate reached 628 revolutions per minute, with throw speeds approaching eighty kilometers per hour on long passes.
Wind tunnel tests confirmed something counterintuitive: when a football is thrown at an angle, air pressure actually pushes the nose downward—not upward as intuition would suggest. This subtle force drives the ball to gradually reorient itself in the direction it's traveling, creating the turnover effect that makes accurate throwing possible.
Critics might note that even with this research, professional quarterbacks have throw styles varying wildly—some emphasize spin more than others—and the exact mechanisms remain subject to ongoing debate among sports physicists. The core principle is sound: without spin, footballs tumble unpredictably and lose velocity rapidly. With proper angular momentum, they maintain orientation and cut through the air efficiently.
Bottom Line
This piece does what Veritasium does best: it takes a seemingly simple question about why we spin footballs and uncovers centuries of physics history hiding behind it. The strongest part is the connection between nineteenth-century rifling technology and modern quarterback mechanics—showing that the same principle that made accurate rifles possible still governs how Brady throws. The biggest vulnerability is that practical takeaways for players are sparse; the science explains what's happening but doesn't significantly improve coaching methods. For readers, the key insight is this: when you watch a quarterback throw a perfect spiral, you're witnessing angular momentum in action—not perfection, but stability.