Laser weapons by 2023

[joepistole]

Yes if you are a ill educated economist and ignore the capital cost.

And you know this how? You don't know that capital costs weren't included in the cost number. But even if that were the case, there is a lot of R&D that goes into creating missile systems too. What's important here is the marginal cost. A dollar versus a million dollars, well, it doesn't take long for those numbers to add up to some very big savings. R&D is a one time cost. Once you have it, you don't have to go back and reinvent the wheel every time you need to use it.

One more point, this has absolutely nothing to do with economics or economists. It has everything to do with cost accounting. Economists don't care how projects are costed. http://www.investopedia.com/terms/c/cost-accounting.asp?partner=asksa

Also, they rarely if ever tell what is the maximum kill range on an aluminum skinned (high refectivity) target

Well, I wouldn't expect them to release maximum kill range information. That's classified information. Generally military folks don't disclose information which benefits potential adversaries. You don't think the US Navy understands the issues you have mentioned? Why do you think this has been long in development? There were a lot of issues to resolve before deployment, like kill ranges and weather,

 

[Billy T]

... Well, I wouldn't expect them to release maximum kill range information. That's classified information. Generally military folks don't disclose information which benefits potential adversaries. You don't think the US Navy understands the issues you have mentioned? Why do you think this has been long in development? There were a lot of issues to resolve before deployment, like kill ranges and weather,

Well During WWII apl/jhu where I worked some years after WWII, made the proximity fuse artillery shell, and saved the US pacific fleet against the Japanese KamaKasai suicide planes, crashing into ships. As a grateful consequence, the Navy has generously funded many Navy projects at APL/JHU for more than 70 years now.

Reason I mention this is that there would be no release of military information if the navy were to tell their Laser could do as well as the WWII proximal fuse artillery shells did - they were indeed very top secret in WWII. So secret that their use in Dunkirk to save the allied forces from being pushed into the sea was requested but not allowed as fear was that if one were a dud and fell on land the capable Germans could "reverse engineer it." Each shell was obviously unique as it had a tiny propeller at the front which ran a tiny generator powering the single tube oscillator - no battery to go bad.

I think the true reason why the navy does not tell the very short effective range and the atmospheric blooming limitations is that would weaken their funding request. In my 30 years at APL/JHU I was aware of many high tech "boondoggles" that were never going to be as good or useful as existing systems, and in many cases the navy knew this, but wanted to advance technology. Same reason NASA funds maned exploration of space, when they know full well instruments are much cheaper and don't need the high cost "man rated" quality controls when building the space ship. If one fails, just send up another for still much less than half the total cost.

All departments of the government love to invest in high tech. For example, APL/JHU got a modest contract to make a high tech system for helping the blind know where the open doors of a metro train were. It had 180 out of phase radiation coming from both sides of each of the subway doors and a small battery powered detector that fit on the blind person's cane to sensed the null by vibrating cane when cane was exactly on the mid line between the two open doors. The sponsor was pleased, but the blind preferred the to sense what other people were doing or use their cane on the side of the rain car to find the door, if they were the only person getting on and no one was getting off.

SUMMARY: there is glamor and funding in high tech, even if less useful than current low tech.

 

[Q-reeus]

The shot was taken near the muzzle, the projectile had no time yet to heat up.
And the original article mentioned plasma behind the projecile, that is ionized air, so it's likely that nitrogene and oxygene react there.

https://de.wikipedia.org/wiki/Railgun

Hinter dem Projektil entsteht durch den großen Druckunterschied eine Plasmawolke.

Translation: Due to the high pressure difference, a plasma cloud is created behind the projectile.

'Igniting the air' doesn't make sense. Look at the visible shockwave profile - well ahead of projectile and quite wide and somewhat irregular. Characteristic of low Mach number probably barely supersonic certainly not close to the ~ Mach 8 implied by 'record...muzzle velocity of 2520 meters per second'. At low Mach number aerodynamic heating will top out at a few hundred degrees C and that only at nose area. However....use of sabot in design complicates what one might expect if just based on pure projectile launch. All that fire is from some combo of vaporized conductors and disintegrating sabot that gets left behind. Actual projectile then cleanly continues with no 'air burning' whatsoever. For a fuller picture of go-to-whoa, see e.g.:

More, with added 'this'l scare the naughty Ruskies' hype:

I guess patriotic Americans are supposed to then loudly chant "U..U..USA!" Err, no thanks.
As per Englander version at https://en.wikipedia.org/wiki/Railgun
the bugbear, as I implied before, is primarily over questions of gun durability. Vaporizing conductors isn't conducive to great lifetimes. Having to regularly replace expendable railing etc. also brings into question reload times. Conventional cannon munitions just don't suffer from such drawbacks. Overall, missiles will continue to be general-use king for quite some time imo.

 

[Dywyddyr]

they were indeed very top secret in WWII. So secret that their use in Dunkirk to save the allied forces from being pushed into the sea was requested but not allowed as fear was that if one were a dud and fell on land the capable Germans could "reverse engineer it."

Yeah right.
Dunkirk occurred 26 May - 4 June 1940. The first PROTOTYPE proximity shells weren't manufactured until sometime in June '40. And it wasn't until a month later that the decision was taken to develop them for use.
And, rather than "enabling the Germans to reverse engineer it" it should be noted that THEY had started work on proximity fuses a number of YEARS before the British.

]Each shell was obviously unique as it had a tiny propeller at the front which ran a tiny generator powering the single tube oscillator - no battery to go bad.

False - they used batteries, and developing those was to take some time: "The outcome of this research was the development of a cylindrical battery resembling a fountain pen. The way this battery worked was ingenious! The electrolyte was contained in a glass ampule at the center of a cylindrical cell of thin plates. Upon the firing of the projectile the shock breaks the ampule, the electrolyte is released and the centrifugal force generated by the rotation of the projectile forces the liquid between the plates and activates the battery. This battery was ready for experimental testing in February 1942". (also related here). Making a "small propeller" able to withstand the 20,000 G or more of firing would have made it prohibitively heavy.

 

[Billy T]

To Dywyddyr thanks for your correction. I was just repeating what I often heard at APL/JHU in 1958 or so. It was word of mouth, many times repeated, with "copy error" accumulating. The no battery story must have developed as it was true APL solved the problem of batteries going dead in storage, and then the propeller was added to the story* to supply energy to the single tube oscillator.

I don't search much - where and how did you get the more correct story?** It was a more clever invention than I was lead to believe. The story I heard was mainly focused on how hard it was to make a vacuum tube survive the huge accelerations. I think that part was only "once removed" from the man who actually worked on that part of the problem.

It was true that there was no danger of it exploding on the ship. Not because the propeller was not yet spnning, as I was told, but because the battery's glass ampule holding the electrolite was not yet broken.

* Perhaps the propeller story was clever dis-information to keep the clever battery secrete longer?

** I did search and found this excellent review: http://www.smecc.org/radio_proximity_fuzes.htm
That link does say: "Realizing that the details of the fuze must be kept from the enemy, the Combined Chiefs of Staff issued a ban against its use in any area where duds or live shells might be recovered by the enemy." This is, with retelling distortions, probably is the origin of "Could not even be used to avoid the Dunkirk disaster."

 

[Dywyddyr]

I don't search much - where and how did you get the more correct story?

Wiki for the dates and a Google search under "power system for proximity fuse".
There's also a DRDO (Indian defence research organisation) publication that covers some of the history.

This is, with retelling distortions, probably is the origin of "Could not even be used to avoid the Dunkirk disaster."

[/quote]
A massive distortion:
Dunkirk, as I noted, was in 1940, the USN, who I believe were the first to introduce proximity fused shells - at least for naval service, didn't start using them until '42.