this post was submitted on 26 Mar 2025
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NonCredibleDefense

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[–] [email protected] 50 points 1 week ago (2 children)
[–] [email protected] 33 points 1 week ago

Nah Mach 19 more than fast enough.

To Mush, though.

[–] [email protected] 15 points 1 week ago (1 children)

Well, how is his wife holding up?

[–] [email protected] 9 points 1 week ago

To shreds, you say? Oh dear...

[–] [email protected] 41 points 1 week ago (4 children)

I know it's not funny, but helicopter ejection seats work by (typically explosively!) jettisoning the rotors prior to the launch of the seat.

At Mach 19, however, you would have probably roughly a 1 in 12 not to take one of the rotors right to the dome on the way out. Do you feel lucky, pilot?

[–] [email protected] 9 points 6 days ago

Nah, has a timing circuit just like the ones warplanes used.

[–] [email protected] 5 points 6 days ago

I think going from 0 to Mach 19 in that short of a distance would pulverize the human body worse than any possible helicopter crash.

[–] [email protected] 24 points 1 week ago* (last edited 1 week ago) (1 children)

They should just shoot ya out the bottom. That way you can get to the ground and back in another chopper faster. 😌

[–] [email protected] 13 points 1 week ago

If you hit the ground fast enough, the crater you make can serve as your grave. That's peak efficiency.

[–] [email protected] 2 points 1 week ago

Goose!

GOOOOOOSE!

[–] kersploosh 31 points 1 week ago (1 children)

There's an additional health benefit. If your spine is turned to jello then you never have to worry about herniated discs in your old age!

[–] [email protected] 18 points 1 week ago

Finally, the military is looking after its vets properly 🙏

[–] [email protected] 16 points 1 week ago (3 children)

Helicopters are actually really neat. If they suffer a loss of power, they can spin up the rotor while falling, and then reverse the blade pitch and turn all that momentum into lift and make a soft landing. Or something like that. Smarter Every Day can explain better: https://youtu.be/BTqu9iMiPIU

[–] [email protected] 2 points 6 days ago

Sort of correct. They can feather the blades to induce auto-rotation. Long explanation short, the rate the blades rotate is based on the total airflow though the rotor disk from any angle, so much like a glider, you can trade forward speed for vertical speed/rotor speed.

[–] [email protected] 7 points 1 week ago (1 children)

Check out "gyrocopters". They look kinda like helicopters, but their rotors are not connected to the engine. Instead, they use a propeller to drive the aircraft forward, and airflow drives the rotor disk.

They operate on the same basic principle as autorotation, but for normal flight rather than arresting an emergency descent.

[–] [email protected] 1 points 1 week ago

Those are so weird! Brilliant.

[–] [email protected] 2 points 1 week ago (1 children)
[–] [email protected] 4 points 1 week ago

The longest helicopter autorotation in history was performed by Jean Boulet in 1972 when he reached a record altitude of 12,440 m (40,814 ft) in an Aérospatiale SA 315B Lama. Because of a −63 °C (−81.4 °F) temperature at that altitude, as soon as he reduced power, the engine flamed out and could not be restarted. By using autorotation he was able to land the aircraft safely.

What a mad lad, setting two records at once.

[–] [email protected] 7 points 1 week ago (4 children)

So I assumed the rotas were about 3 meters from the cocpit and asked Gemini.

To calculate the g-force experienced during this acceleration, we need to go through a few steps:

  1. Convert Mach 19 to meters per second (m/s):
  • The speed of sound in air varies with temperature. At a standard temperature of 20°C (68°F), the speed of sound is approximately 343 m/s.
  • Mach 19 is 19 times the speed of sound.
  • Therefore, Mach 19 ≈ 19 * 343 m/s = 6517 m/s.
  1. Calculate the acceleration in m/s²: We can use the following kinematic equation:
  • v_f² = v_i² + 2 * a * Δx
    • Where:
      • v_f is the final velocity (6517 m/s)
      • v_i is the initial velocity (0 m/s, assuming starting from rest)
      • a is the acceleration (what we want to find)
      • Δx is the distance (3 meters)
  • Plugging in the values:
    • (6517 m/s)² = (0 m/s)² + 2 * a * (3 m)
    • 42,471,289 m²/s² = 6 * a m
    • a = 42,471,289 m²/s² / 6 m
    • a ≈ 7,078,548.17 m/s²
  1. Convert the acceleration to g's:
  • One g is the acceleration due to gravity at the Earth's surface, which is approximately 9.81 m/s².
  • To find the acceleration in g's, divide the calculated acceleration by the value of one g:
    • g-force = a / 9.81 m/s²
    • g-force = 7,078,548.17 m/s² / 9.81 m/s²
    • g-force ≈ 721,564.5 g Therefore, you would experience an acceleration of approximately 721,564.5 g while accelerating to Mach 19 over a distance of 3 meters. Important Note: This is an extremely high level of acceleration, far beyond what any known biological organism or material could withstand. Such forces would be instantly fatal and would likely cause catastrophic structural failure.

I'm sure someone who's better at maths than me can tell me where the llm has gone wrong. But it sounds impressive.

[–] [email protected] 3 points 6 days ago (1 children)

The ejection seat booster is actually a nuke.

[–] [email protected] 1 points 6 days ago

It's the logical evolution of Operation Plumbbob's missing steel bore cap.

https://en.m.wikipedia.org/wiki/Operation_Plumbbob

[–] Kalcifer 1 points 6 days ago (1 children)

[…] I’m sure someone who’s better at maths than me can tell me where the llm has gone wrong. […]

From what I can tell, the math is sound.

[–] [email protected] 1 points 6 days ago
[–] [email protected] 14 points 1 week ago

I wouldn't even trust Gemini to set my alarm (it can't btw, it fucks up on something as simple as setting the alarm, wtf?)

[–] [email protected] 8 points 1 week ago (1 children)

So it's a pancake launcher.

[–] [email protected] 18 points 1 week ago* (last edited 1 week ago) (1 children)

A man with an average height of 1.8 M and average weight of 89kg at 1G would weigh about 58,446 metric tonnes. To put that in perspective it's just a little under three quarters of the weight of a Queen Elizabeth class Aircraft Carrier or almost exactly 10% of the weight of your mum.

[–] [email protected] 3 points 1 week ago

basically how the BLJ in Mario 64 works

[–] [email protected] 3 points 1 week ago (1 children)

They could design one that ejects you sideways

[–] [email protected] 1 points 6 days ago

Powered by nitrous oxide like in the true crime documentary 2 Fast 2 Furious