[anonymousiam]

Lasers can stop a hypersonic missile, but the challenge is getting a beam on the target through the atmosphere. Some of the old SDI tests solved the problem by flying the laser above most of the atmosphere.

https://en.wikipedia.org/wiki/Boeing_YAL-1

[eightysixfour]

What is the math on how much additional heat a laser would deliver to a warhead which is presumably designed with some kind of ablative shielding that is pushing through air compressed into a plasma? It seems like the damage from a laser pointed from miles away through atmosphere wouldn't be enough to change anything.

[jandrewrogers]

A practical laser is unlikely to cut through ablative shielding. There are a couple of caveats to this though.

First, asymmetric ablation can destroy hypersonic vehicles extremely quickly. It is a major cause of failure in hypersonic vehicles even when no one is shooting lasers at it. A laser just needs to induce the ablation asymmetry; the physics of hypersonic vehicles will do the rest of the work.

Second, precision terminal guidance systems can't function behind ablative shielding. The terminal guidance system has no protection from high-power lasers.

[echoangle]

The linked plane was supposed to destroy missiles directly after launch (presumably by destroying the less-protected missile body instead of the entry vehicle).

[adrian_b]

This is mentioned in TFA.

The current lasers are not powerful enough for this purpose, they may be efficient only against drones or other slower targets.

[buildsjets]

As noted in the Wiki, even with a megawatt class laser, you would need the aircraft to be operating inside the borders of Iran for it to be effective, and we do not have air superiority in Iran to be able to do that with a big slow 747. And to be operationally effective, we would need a fleet of twenty of them.

[dylan604]

There was also the Adaptive Optics where the beam was shaped by lot of individual articulated mirrors that could be used to correct the beam from not only the atmospheric distortion but how the heat of the beam itself would then change the atmospheric distortion. Supposedly, that tech became DLP.