One wing, one steel pole, and the arithmetic
Same wing. Same steel.
2,500× the force.
Steel has a fixed breaking point. The force arriving at it does not: it grows with the square of speed. Below the line the wing loses. Above it, the steel does.
I’m arguing one thing here. A wing hits a steel column at 500 mph, and the column shears. That’s the whole argument. This is just about a wing and a pole.
Every step across this scale is ten times the step before it. That’s the only way both bars fit on one screen. The bottom bar is 2,500 times the top one, not five times.
A photograph, not a simulation
Sand cuts steel, and the only reason is speed
That’s ordinary sand in the stream
Poured onto the plate it does nothing at all. Carried fast enough it cuts straight through. The sand never changed. Only its speed did.
Nobody argues about this one, because everyone has seen it. Same argument, with the plane taken out.
Abrasive waterjet · WARDJet, CC BY-SA 2.0, via Wikimedia Commons
The actual arithmetic
Two equations. One of them has a v² in it.
What the column can hold
F = τ × A
τ = 207 MPa steel shear strength
A = 8,871 mm² 14 in box column, ¼ in wall
F = 1,836,297 N
What the wing delivers
F ≈ m × v² ÷ d
m = 139 kg the piece of column in the path
d = 0.3556 m how deep that column is
v = the only thing that changes
| v = 4.4704 m/s | (10 mph) | 7,812 N | 0.4% of the limit |
| v = 223.52 m/s | (500 mph) | 19,529,262 N | 1,063% of the limit |
Same equation. Same column. Same wing. Only v changed.
Notice what’s not in it: the plane. The force depends on the column and the speed, nothing else. And the ratio holds no matter what you think of my constants, because they cancel. Fifty times the speed is 50² = 2,500 times the force, exactly. You can halve every number above and 500 mph still clears the limit five times over.
The wing does not have to survive. It has to deliver. It carries that pressure for 1.6 milliseconds. It is confetti either way, and so is the column.
At speed the column is standing alone. A column is strong partly because it is bolted to everything around it, and that help arrives as a wave through steel at about three miles per second. Contact at 10 mph lasts 80 ms, long enough for the signal to travel 400 meters and for the rest of the frame to lean in. At 500 mph contact lasts 1.6 ms and the signal travels 8 meters. Nothing past that has found out yet.
Your hand cannot push a nail into wood. A hammer does it instantly. The hammer is not harder than your hand.
The two things people say next
"The wing would be destroyed."
It would be. Completely. Destroyed and harmless are two different words. A thrown wine glass shatters and the window still breaks.
"The photo shows a pole winning."
At walking pace, over about a tenth of a second. Everything has time to flex and share the load, so the wing is the weak one. That’s the top bar on the chart, and it flips with speed.
Every number above, and where it came from
| Quantity | Value | Type | Source or method |
|---|---|---|---|
| The two speeds | 10 / 500 mph | Given | Ramp speed against flight speed. These two are the inputs under argument, and everything else on this table follows from them |
| Column section | 14 in box, ¼ in wall | Given | A standard hollow square structural steel column, ASTM A500 |
| Steel shear strength (τ) | 207 MPa | Derived | 0.6 × 50 ksi yield. AISC 360-22 Section G takes shear yielding at 0.6 Fy; ASTM A500 Grade C is Fy = 50 ksi |
| Column cross-section (A) | 8,871 mm² | Derived | 14² − 13.5² = 13.75 in², the steel actually on the shear plane. Nominal wall, which is the assumption that favors the column |
| Column section mass (m) | 139 kg | Derived | A 2 m length of that section at 7,850 kg/m³ |
| Column depth (d) | 0.3556 m | Derived | 14 in × 0.0254 |
| Wave speed in steel | ~5,100 m/s | Published | Standard longitudinal wave speed for structural steel |
| Contact time | 80 / 1.6 ms | Derived | Column depth ÷ speed: 0.3556 m ÷ 4.4704 and ÷ 223.52 m/s |
F ≈ m v²/d is an order-of-magnitude scaling estimate, not a finite element model. It answers one question: why the same steel survives one collision and fails the other. The constant in front is arguable. The v² is not.