> Large passenger aircraft do not cruise on all > their engines, typically.
This is not true.
> I've been on 747s with the jetstream going the > right way that I swear were crossing the > Atlantic on one engine.
A 747 of any type cannot fly level on a single engine (unless, maybe, there are no passenger, cargo and almost no fuel present).
> And, when crossing the Pacific, or the Arctic, > how much do you want to rely on only 2 engines?
A lot of flying today is done with two engines only, even over the Pacific or the Arctic. There are strict requirements. Google for EROPS or ETOPS. Modern engines are very reliable that diversion landings for other reasons (e.g. medical) are more frequent than engine failures.
E.g. the most recent version of the B777 will be certified to fly on one single engine for 330 minutes (ETOPS-330) in case of an engine failure. This gives enough room to cross even remote areas.
Because silicon is well established in the semiconductor industry and therefore cheap to obtain easy to process into semiconductor devices.
On the other, almost all optical devices (LEDs, laser diodes) are made from III-V compund semiconductors like Galliumarsenide (GaAs), InAs, AlAs, GaN, GaP and so on. These are not available as large crystalline blocks and thus there are no such things as 300mm wafers. They are usually fabricated by expensive methodes. However, they are the only practical solution because the are so-called direct semiconductors - you just cannot do optics with indirect band-gap semiconductors like silicon.
Now, if you find THE technological trick to do optics with silicon, you benefit from the cheap silicon technology and are ready to build optical computers with cheap fabrication technology. There are some tricks around already like mixing silicon with germanium (SiGe) or putting in nano-crystals so the silicon are catching up in doing optics.
Their headline is something like "EU Parliament Stops Software Patents.
It might be appropriate to put emphasis on the most important word in the headline of heise.de.
"European Parliament turns down pure software patents."
This reads different!
According to this message (again, German) the bill has passed the EP but got some major changes. E.g. no patents for business ideas, algorithms. Computer patents only when connected to engineering and the "respective forces of nature."
Don't tell anyone but I have even forgotten to turn off my cell phone for a whole flight right in the cockpit (OK maybe even more that once). The most likely interference to navigation will be external...
I don't fly but my pilot friend nearly crashed 10 years ago when he was F/O on an ATR-42. They got a trim (electrically controlled) runaway to full nose down on final approach resulting in an steep dive. Only solution to regain control was pulling the circuit breaker.
Probable cause: captain forgot his mobile phone on the glareshield.
The interference was not reproduceable on the ground. That's the problem. Interference does not happen always but might be disastrous one day.
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> Large passenger aircraft do not cruise on all
> their engines, typically.
This is not true.
> I've been on 747s with the jetstream going the
> right way that I swear were crossing the
> Atlantic on one engine.
A 747 of any type cannot fly level on a single engine (unless, maybe, there are no passenger, cargo and almost no fuel present).
> And, when crossing the Pacific, or the Arctic,
> how much do you want to rely on only 2 engines?
A lot of flying today is done with two engines only, even over the Pacific or the Arctic. There are strict requirements. Google for EROPS or ETOPS. Modern engines are very reliable that diversion landings for other reasons (e.g. medical) are more frequent than engine failures.
E.g. the most recent version of the B777 will be certified to fly on one single engine for 330 minutes (ETOPS-330) in case of an engine failure. This gives enough room to cross even remote areas.
Because silicon is well established in the semiconductor industry and therefore cheap to obtain easy to process into semiconductor devices.
On the other, almost all optical devices (LEDs, laser diodes) are made from III-V compund semiconductors like Galliumarsenide (GaAs), InAs, AlAs, GaN, GaP and so on. These are not available as large crystalline blocks and thus there are no such things as 300mm wafers. They are usually fabricated by expensive methodes. However, they are the only practical solution because the are so-called direct semiconductors - you just cannot do optics with indirect band-gap semiconductors like silicon.
Now, if you find THE technological trick to do optics with silicon, you benefit from the cheap silicon technology and are ready to build optical computers with cheap fabrication technology. There are some tricks around already like mixing silicon with germanium (SiGe) or putting in nano-crystals so the silicon are catching up in doing optics.
I still maintain the idea that the bandwith of a 800' container ship full of 200 GB hard disks shipped across the Atlantic is huge, e.g. 50 Pb / s.
Ping time, however, is probably pretty low (10 days) and if the ship sinks you'll have 100% packet drop - eh - loss.
The BBC story saying he has no 'contingeny plan' and not cared about 'Search & Rescue'. If the pilot doesn't care about S&R in remote areas, he has done poor planning. Considering any emergeny which forces him to land away from any base as unlikely is just dump. I've read Impact Erebus by Gordon Vette which is about the story of the Air New Zealand DC-10 which near McMurdo in 1978. Even a Search & Rescue operation close to McMurdo was incredibly complicated and no one wants to search a crashed pilot when it's even unlikely to find him (he hasn't told anyone) and it's unlikely for him to survive. I'm not surprised that people don't encourage him to continue. Besides ... he has probably landed his airplane at cMurdo Williams Field. There is no such thing as a runway at the New Zealand base, the only other runways down there are the Pegasus Field and the Ice Runway both located a few miles away on the shelf ice.
fm
Their headline is something like "EU Parliament Stops Software Patents.
It might be appropriate to put emphasis on the most important word in the headline of heise.de.
"European Parliament turns down pure software patents."
This reads different!
According to this message (again, German) the bill has passed the EP but got some major changes. E.g. no patents for business ideas, algorithms. Computer patents only when connected to engineering and the "respective forces of nature."
Don't tell anyone but I have even forgotten to turn off my cell phone for a whole flight right in the cockpit (OK maybe even more that once). The most likely interference to navigation will be external...
I don't fly but my pilot friend nearly crashed 10 years ago when he was F/O on an ATR-42. They got a trim (electrically controlled) runaway to full nose down on final approach resulting in an steep dive. Only solution to regain control was pulling the circuit breaker.
Probable cause: captain forgot his mobile phone on the glareshield.
The interference was not reproduceable on the ground. That's the problem. Interference does not happen always but might be disastrous one day.