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Comment Lunar regolith - thermal, radiation, micro-meteor (Score 1) 194

read up on atmospheric pressures and temperatures, specifically the extremes on Mars vs. those on the Moon, and the relative radiation levels. Basically you can use a similar design but you have to overengineer the hell out of it to make it feasible on BOTH, because the Moon has no ozone and has ridiculous 28-day cycles with insane temperature extremes.

Well any equipment dealing with water ice would be in the shade and not subject to lunar temperature extremes, that is how the the ice has survived after all. As for equipment on the surface exposed to sunlight, go underground or make shade. There are lava tubes in places waiting to be used. Or one can build walls from the lunar regolith. Or one can put up a tarp like when camping in the desert, no wind on the moon so its more practical than on mars. The lunar regolith has the advantage of also helping with micro-meteors and provides some radiation shielding.

Comment Re:Moon as a gas station (Score 1) 194

because water ice on the Moon is very scarce, present mostly in shadowed polar craters where solar power doesn't work very well (but maybe nuclear?)

Put the solar panels outside the crater, or in part of the crater that does get sunlight, and run a cable.

Comment Energy is plentiful on the moon ... (Score 1) 194

Hey genius. It takes more fuel to split water than you would get afterwards by burning hydrogen...

No. It takes more energy. And transforming energy from one form to another is quite useful, as in converting solar to fuel. Look out a window and find a plant, it is converting solar energy to fuel, sugar, via photosynthesis. On the moon use solar energy to power the electrolysis of H2O into H2 and O2. Or if you happen to have a handy nuclear power source ...

Comment Impact energy distributed (Score 1) 143

These hedgerows were not what people in the US and UK think of when someone says hedges. That was part of the problem, people in the US and UK were not used to seeing vegetation that tanks could not knock down or plow through so it was a blind spot of sorts.

These hedgerows were incredibly large and dense with branches, vines and roots interlocking. When they took a hit from a tank the energy of impact would get distributed, its a little bit like the special fibers and weaves that help to distribute impact energy over a large area in some bullet resistant vests. They needed something to cut these branches and vines to interfere with this energy distribution.

Or maybe think of a net, one wants to cut a slot in the net to pass through.

Comment Germans ran out of ammo before US ran out of tanks (Score 1) 143

The hedges were generally at ground level but the roads were often sunken. Traveling along these roads was dangerous. That was expected, that was where all the weapons were pointed. To maneuver freely, off-road, one had to get through the hedgerows.

With respect to German 88mm guns it didn't matter where the US tank was hit, they didn't need to hit the thinly armored bottom. Those guns were exceptionally deadly and were waiting for tanks to drive down the road. I recall reading a US veteran's recollection. The US soldier was annoyed at the smug look of a captured German officer. He asked the German if they were such supermen why was he a prisoner. The German responded in English: I commanded an 88mm gun battery. Every time an American tank came down the road we destroyed it. Eventually we ran out of ammunition, you did not run out of tanks.

Being a US tanker in the European theatre was extremely hazardous. You really didn't want to be seen or travel where expected. Roads, at ground level or sunken, were dangerous.

Comment Re:Blacksmith/Welder not Engineer ... (Score 1) 143

The ability of tanks to knock down trees and crash through brush in North America and England probably gave them a false sense of security. They just did not fully understand the density of the bocage. Its not unlike layers of specially weaved fabrics in old "bullet proof" vests, spreading the energy of impact over a larger surface area and preventing penetration.

Comment Re:Blacksmith/Welder not Engineer ... (Score 1) 143

It is engineering - they're operating, maintaining, and modifying machines with engines. There's a handful of clowns out on a "we need REAL engineers" campaign on Slashdot, yet they don't know WTF a real engineer is.

Actually I'm quite familiar with the more archaic definition of engineering. My grandfather was licensed to operate and maintain various types of machinery in that domain. For example a stationary engineering license to operate a power plant in an industrial setting, i.e. boil water, produce steam, drive turbines, etc. "Stationary" to differentiate it from railway locomotives, locomotive engines, ship propulsion, etc.

However in either the more modern or more archaic usage of "engineering" the word does not apply to this Normandy event. It was truly a hack. A complete jury-rigged improvisation with materials at hand, something expedient for the field for now. "Engineering" would be more appropriate for something with a little more design and/or a more long term solution. Later more robust engineered variants of this idea would appear.

Comment Blacksmith/Welder not Engineer ... (Score 2) 143

Sure, it's old technology, old engineering. But so is ENIAC...

Not "engineering" in the sense that engineers at a company came up with the device. The phrase "hack" is entirely appropriate. This modification came from a Sergeant at Normandy who thought he could cut up some of the i-beam based beach obstacles and make "teeth" for the tanks. So the solution came from the blacksmith/welder types, an actual Army MOS, improvising something on the spot not the engineers designing something to meet a requirement.

Comment Re:Bitcoin seizure (Score 1) 114

At his peak, he controlled about 7 percent of all Bitcoins in circulation.

Although the article doesn't explicitly say so, his bitcoin wallet was presumably seized as part of his arrest and conviction. Given this and other similar high profile cases, it seems that the U.S. government may now control a not-insignificant minority of all bitcoins currently in circulation.

Until the hard drive with the wallet (encryption keys) crashes and we find that there are no backups. :-)

Comment Re:A-10 for the win! (Score 1) 320

In the 1970s you could take a thousand pilots, throw them at the enemy, and hope you got back half of them. You can't do that anymore.

No. A small fraction of such casualties over a much longer timeframe forced the end to US involvement in Vietnam. You didn't naively think it was hippies protesting in the streets that ended it did you? It was casualties and the resulting loss of faith by mainstream America that did it in the late 1960s.

Comment Re:You misrepresent the F-111 (Score 1) 320

Except you would be wrong. The Air Force wanted an aircraft that could serve as a fighter/bomber, and the Navy wanted a fighter/interceptor to defend Carrier task forces against Russian bomber/cruise missile attack swarms. McNamara made them combine their requirements into the "Tactical Fighter Experimental" (TFX) program, and it was a "fighter" in that it was intended to use missiles at range to shoot down enemy aircraft, in an era where dogfighting was considered to be obsolete.

No. The Air Force's primary interest was that of a bomber, and the Navy that of an interceptor. Fighter was a very secondary thing. Much like the F-117 can mount sidewinders for air-to-air, or an A-10 for that matter too. Its more a self defense thing. That does not make an aircraft a "fighter". Note the distinction between "fighter" and "interceptor", the later has more to do with taking out big slowly maneuvering bombers. The F-111 was actually envisioned as an answer to both sides of this traditional "interceptor" mission. For the Navy it attacked the bombers. For the Air Force it replaced the big low maneuverability bombers at altitude with small fast terrain hugging bombers, aircraft far more likely to find gaps in Soviet air defenses.

The F-111 was never intended to be a front line fighter like the F-4. And it was the F-4 in that era that was intended to be a front line fighter that shoots down enemy fighters at range with missiles. Early F-4 versions did not include guns.

Meanwhile, the Air Force would use it mostly as a tactical bomber, and also made an adapted version to use as a strategic bomber, and it did a pretty decent job of those - but it could have done much better had it been designed to do just that rather than trying to be everything to everyone.

That was the role the Air Force had always been working towards. And not everything, not a "fighter", just a bomber and and "interceptor". Again an "interceptor" is not a "fighter", different prey so to speak, primarily targeting bombers and such.

And I can only imagine what would have happened had the Marines demanded it be SVTOL capable, too.

To be clear I am not in favor of multi-mission aircraft. I prefer the 1970s renegade sort of approach that led to the single purpose designs of the F-16 and A-10. That is not to say there isn't more opportunity for common components. We probably could have more standardization and commonality with respect to avionics, maybe more aircraft sharing engines.

STOVL would probably have to be its own single purpose design, its hard to imagine vertical landing being a general purpose win over ruggedness. Or maybe it would be a better idea to adapt amphibious assault ships for STOL (no vertical). No need for the complex arresting gear of a carrier that supports many aircraft types. Maybe something simpler for a single type of aircraft, whatever STOL the Marines are operating. I understand OV-10 have been launched and recovered by assault ships but something closer to an A-10 would be needing more runway so arresting gear of some sort would be necessary.

Comment You misrepresent the F-111 (Score 1) 320

You seem to be making the common mistake that an "F" designation necessarily means the aircraft is a fighter designed to mix it up with other fighters. That is not true. Sometimes tactical bombers get the "F" designation, F-111 and F-117 for example. The F-111 was designed for deep strikes behind enemy lines behind a defensive line of fighters and surface to air missiles. The idea was that extreme low altitude flight, computer assisted nap of the earth, would allow the F-111 to avoid SAM radar; and that high speed at these altitudes would help to avoid fighters which were generally less capable at low altitudes. That was the "intent" of the F-111, it was not an F-4 replacement.

Now the F-111 may have also had some fighter roles in mind, but such were more like intercepting Soviet bombers coming south from the north pole. Or in the Navy's version of the scenario intercepting Soviet bombers heading towards a carrier. Note quite a fighter-on-fighter scenarios.

Comment Re:A-10 for the win! (Score 1) 320

Both the superTucano and the A-10 are irrelevant against a modern IADS, and will be bled by modern handheld SAMs.

An argument made in the 1970s when the A-10 was being forced upon the Air Force. And yet it turned out to be quite useful over the decades.

For the record, fighters do even worse against IADS. See WW2, Korea, Vietnam and various Arab/Israeli conflicts. The A-10 was designed with the lessons of these wars in mind. Nap of the earth flight, ruggedness, etc.

Drones have their utility but they are not a complete replacement. Well maybe for the F-35, given that it will probably be required to operate at higher altitudes and such given the previously mentioned weaknesses of fighters in the CAS role. However for a low, slow highly maneuverable aircraft with a pilot with a head on a swivel and who understands infantry operations and can evaluate what he sees at a glance the drone can come up lacking. The drone is no "magic bullet". We also need a manned aircraft like the A-10 as well.

All science is either physics or stamp collecting. -- Ernest Rutherford