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Comment: Re:Sure ... (Score 1) 154 154

> you totally destroy your credibility with the 3.0 Gs thing.

If you want to mess about with aircraft there are planes you can do this in, and places you can have the altitude to do it. It's harder to lift your arms but not intolerable. In general, unless the passengers are warned in advance it's best not to exceed 0.5G in banked turns and exceeding 2G may pull the wings off some models of light aircraft.

> actually be comparable to a roller coaster.

Roller coasters are deliberately designed to repeatedly throw people around in different directions in order to heighten the sense of danger. High speed banked turns in hyperloop (or anything comparable) are in no way comparable to the feeling of a roller coaster, more like riding in a widebodied air transport (note there that the apparent cabin gravity is also always floorwards thanks to banked turns.)

Anyone who tries to make out that passengers will feel substantial lateral forces is barking up the wrong tree. Even the original vacuum train proposals made use of banking in turns and european HSR systems make extensive use of banking to avoid the same effects (You can feel the apparent gravity pushing you into the seat a little harder in some spots on the Paris-Amsterdam run).

Any credibility loss is borne by those who try to compare the ride quality of a high speed transport system to a roller coaster. The ride on rails is comparable to that of a ship or an aircraft (without pitching and rolling) and in a tube will be even smoother than that of a maglev (try the shanghai airport shuttle sometime. It's like a magic carpet.)

Comment: Re:citation please (Score 1) 116 116

Golfballs are rotating and the dimples help create lift by breaking up the turbulent flow at the rear of a spherical ball (This is more related to small scale bluff body aerodynamics than aerofoils)

Aircraft wings are not rotating, nor do they have spherical trailing edges.

A sharkskin covering might help make wings "slicker" by easing transition layer drag but we're a long way away from the materials science needed to make one which is both straightforward to apply and which will stay in place for prolonged periods.

Highly polished leading edges have been known to help for a long time but those are labor-intensive to maintain.

Comment: Re:Bugs on a plane (Score 1) 116 116

"Stealth" aircraft are only stealthy at certain frequencies and certain angles, plus they have a nasty tendency to be Hangar Queens.

The F-35 sticks out like dogs bollocks once you're 35 degrees off the nose (ie, no stealth at all) and the B2 was happily tracked right across England by the RAF's radar system (Both are totally visible to russian VHF radar and Over-horizon systems like Australia's Jindalee)

The intent of "stealth" aircraft is to get past local defences before they're noticed. Even mach 6 SAMs have trouble catching up to the tailpipe of a passing B2, but the whole model falls apart if the defence systems are regionally networked such that missile systems ahead of the aircraft can be directed by radar systems behind it.

Comment: Re:And ticket prices? (Score 1) 116 116

> They then turn around and argue something magical about competition driving prices down.

That's because the price isn't "Costs plus a markup", it's "Whatever the market will bear"

Competition forces the price down to the former by giving the market a choice, otherwise vendors will charge whatever they like, because they can.

Comment: Bitcoin won't help (Score 1) 358 358

Greece has run for the last 200 years by borrowing large sums of money and defaulting on the debt, then devaluing the local currency.

The national religion is tax evasion. (One example: Those bits of rusty metal you see sticking out of the roof of almost every greek house? That's because you don't pay property tax on an unfinished building, so the buildings are never quite finished.)

The mistake they made was joining the Euro via an outrageous act of fraud (the EU and banks looked the other way for that one) and expecting to keep going like they'd done in the past. Unlike USA states which may get federal top-up funding, individual EU countries are expected to run their own financial policies and keep the books balanced.

They'd be just as fucked now if they'd decided to use the US$ as their currency. The greek people have been relying on a constant influx of foreign money to allow people to retire at 50 (or younger), whilst young greeks have been leaving in droves (no income tax base to pay those pensions) and those left have been systematically defrauding the taxman whilst politicians enriched themselves too.

Short of unilaterally declaring that pensionable age is now 68 and anyone younger than that has to go back to work, along with reforming the tax system and going hard against political and civil service corruption, anything that greece does to get more money is simply staving off the inevitable.

Comment: Re:Not surprised (Score 1) 325 325

The Knowledge applies to a specific area in London (mainly the "square mile" of the original City of London) and they're notorious for not knowing the way outside those confines, or refusing to take fares south of the river (illegal to refuse if journey is less than 12 miles), dogs and other pets (illegal to refuse), and in a few cases for sex offences which for years were blamed on unlicensed drivers.

Only tourists or those not paying the bill take a black cab. Everyone else calls a minicab (or Uber).

Comment: Re:GM Diesels (Score 1) 247 247

"Sadly we don't even get the best diesels Europe has to offer because there just isn't a big enough market"

Plus the "small" issue that until recently the EU didn't regulate NOX, so eurodiesels didn't comply with USA limits.

Eurodiesels require ultra-low-sulfur diesel. USA diesel in most areas is still filthy despite reduced levels in the last 5 years.

Comment: Re:diluting the market (Score 1) 247 247

Even if you went to 4 motors you'd want to keep them inboard for reasons mentioned.

On top of the unsprung weight issues, hubmotors would take an absolute pounding from potholes.

That said, the advanced ones aren't much heavier than a disc/drum brake assembly.

Comment: Re:just die already (Score 1) 124 124

In 2001 I was operating mirrors of several sites and had the mirror scripts set to not delete things if the master "went away", following incidents in 1994

More importantly the ftp sites themselves were supposed to be publicly accessable mirrors of archives of software collections - the point being that there were master copies "somewhere".

In 1997-1999 there had already been a number of instances of script kiddies wiping out ISP webservers (and their disk-based "backups"), which underscored the importance of keeping a master copy of your work somewhere offline and out of reach of accident or malice.

You can do this in a number of ways. IBM chose to do all of them. Why do you find that funny? -- D. Taylor, Computer Science 350