FE Meme
SR-71 Mach 3.2, Shuttle Mach 23?
#160: If an SR-71 needs its delta-wing design just to reach Mach 3.2 in air, believing a Space Shuttle can hit Mach 23 means you are not thinking clearly.
The Meme
Two-panel meme: head-on SR-71 on a runway under "THIS IS THE DESIGN THAT AN AIRPLANE NEEDS TO REACH A TOP SPEED OF MACH 3.2"; below, shuttle in landing config under "SO IF YOU BELIEVE THIS THING IS ABLE TO REACH A MAXIMUM SPEED OF MACH 23, YOU ARE NOT THINKING CLEARLY."
Why It Spreads
Side-by-side photos make the shuttle look like another airplane with an absurd Mach 23 sticker next to an SR-71 that visibly needs delta wings for Mach 3.2. Viewers who already doubt NASA footage treat the contrast as catching a math error in one glance, because both vehicles are framed as competing runway top-speed contestants.
What It Gets Wrong
The two-panel meme pairs a head-on SR-71 under "THIS IS THE DESIGN THAT AN AIRPLANE NEEDS TO REACH A TOP SPEED OF MACH 3.2" with a shuttle in landing config and "SO IF YOU BELIEVE THIS THING IS ABLE TO REACH A MAXIMUM SPEED OF MACH 23, YOU ARE NOT THINKING CLEARLY." Mach numbers compare local airspeed to the speed of sound in the surrounding air; the Blackbird cruises near Mach 3.2 in thick air around 25 km altitude, while a shuttle returning from orbit near 400 km bleeds orbital energy in thin upper atmosphere during reentry. Orbital velocity near 7.8 km/s (~Mach 25 equivalent) is achieved by rocket thrust in vacuum, not by delta-wing runway design alone. TestTheGlobe's Satellites Are Not Real and TestTheGlobe's Earth Rotation Speed walk through the observations and predictions this image skips.
The Debunk
Orbital velocity near 7.8 km/s (~Mach 25 equivalent) achieved by rocket thrust F = ṁ × v_exhaust in vacuum predicts shuttle reentry heating in rarefied air above ~50 km; that fits a different regime than SR-71 cruise at Mach 3.2 in thick air near ~25 km. Side-by-side runway photos treating both as competing top-speed contestants are inconsistent with how each vehicle's speed is measured and achieved. Use TestTheGlobe's Earth Rotation Speed to compare the meme's claim with a measurable prediction.
- TestTheGlobe's Satellites Are Not Real page covers how orbital mechanics and reentry profiles differ from atmospheric jet cruise, the regimes the meme conflates.
- TestTheGlobe's Apollo Moon Landings Were Real: orbital velocity near 7.8 km/s (~Mach 25 equivalent) is achieved by rocket thrust in vacuum, not by delta-wing runway design in thick air.
- TestTheGlobe's Satellites Are Not Real: reentry heating and communications blackout occur in rarefied air above 50 km at hypersonic Mach numbers, not at Blackbird Mach 3.2 cruise conditions.
- TestTheGlobe's ISS Zero-G Is Real: orbital velocity is achieved by rockets in vacuum via F = ṁ × v_exhaust; comparing it to delta-wing runway design ignores the propulsion and medium entirely.