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Let's say you have a B-41 nuclear bomb with a yield of 25 megatons.

It ground bursts in the direct center of Madrid, Spain.

A Boeing F/A-18E/F Super Hornet multirole fighter is flying directly away from the bomb (I imagine it doesn't particularly matter which heading/direction) at a steady rate of 280 meters per second overland.

At the instant the bomb detonates, said aircraft is 13.7 kilometers away from the bomb and 5 kilometers above sea level; it is maintaining level flight (i.e. not flying up or down).

What would the thermal and blast effects on the plane be? Assume that it is painted in antiflash white to minimize thermal effects.

When would the blast wave catch up with it?

If said effects are so extreme as to render flight impossible, or so negligible as to not effect the airplane, what is the minimum distance at which this aircraft can survive and continue to fly for several more minutes?

Assume that buildings somehow don't produce a damping shadow.

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    $\begingroup$ Looks like your Super Hornet is in a worse position than Tu-95V was during Tsar Bomba test. Yield here is half as much, but the distance is 3 times shorter. In 1961, Tu-95V was given a 50% chance of survival. $\endgroup$
    – Alexander
    Jul 24, 2021 at 0:00
  • $\begingroup$ "Moderate blast damage radius (5 psi): 13.4 km (563 km²) At 5 psi overpressure, most residential buildings collapse" - I'm guessing your military vehicle should survive. $\endgroup$ Jul 24, 2021 at 0:10
  • $\begingroup$ @Alexander I saw the page on Tsar Bomba and set it up on Nukemap 2. The Tu-95V was hit with the shockwave somewhere between the radius at which first-degree burns are 50% likely and the "no-thermal-harm" radius, and yet it still dropped a kilometer in altitude while very far outside even the 1 PSI overpressure radius. It also survived at least 35 cal/cm^2 thermal effects. The F/A-18 is hit in roughly the same place relative to magnitude. I'm just wondering what the distance is to outrun the overpressure wave just long enough for it to be heavily damaged but still capable of flying. $\endgroup$
    – KEY_ABRADE
    Jul 24, 2021 at 0:19
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    $\begingroup$ @SurpriseDog The thing is, though, the overpressure wave doesn't hit it right away. The thermal effects do, but it'll outrun the overpressure wave to a certain extent. IIRC, eventually the overpressure wave of a nuclear blast eventually slows to below 280 m/s; I just don't know whether it'll do that before it catches up with the F/A-18, and what will happen to the plane if it does. $\endgroup$
    – KEY_ABRADE
    Jul 24, 2021 at 0:21
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    $\begingroup$ Directly away from the bomb, go full afterburner and I think they outrun the blast wave, they certainly reduce it considerably. $\endgroup$ Jul 24, 2021 at 2:52

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The plane is probably fine.

The Tsar bomber plane, which was specially painted with heat resistant paint, was given a fifty percent survival rate at a much greater distance. While the yield was twice as high, it was three times further away.

The mushroom cloud of Tsar Bomba was seen from a distance of 161 km (100 mi). The crown of the cloud was 65 km (213,000 ft; 40 mi) high at the time of the picture. Both aircraft were painted with special reflective paint to minimize heat damage. Despite this effort, Durnovtsev, and his crew, were given only a 50% chance of surviving the test.

The nuclear bomb blast will travel at about the speed of sound. Catching up at +20m/s it will take around 700 seconds to close up 14 kilometers gap, which gives you enough time to travel 196 kilometers (700*280). You'll be fine.

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  • $\begingroup$ The speed of sound is ~340m/s . So delta-v is ~60m/s. catchup time, if i did not miscalculate, is some 200 secs, at a total distance of ~70km (calculation: 13700+(x*280) = x*340 ) $\endgroup$
    – Burki
    Jul 28, 2021 at 12:47
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    $\begingroup$ They travel at about the speed of sound, not at the speed of sound. They travel at 300m/s. $\endgroup$
    – Nepene Nep
    Jul 28, 2021 at 13:44
  • $\begingroup$ oh. i had that wrong. Thank you for clarifying! $\endgroup$
    – Burki
    Jul 29, 2021 at 7:18

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