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Comment Re:Not nuclear fear (Score 1) 419 419

RTFA.

We know NOTHING about happened during the 7 months between the landing and the solar panels starting to get enough light that they could get the batteries back up.

We have NO idea whether anything "interesting" was happening during that time.

Your definition of "success" is "Well, it works now, because we got half-lucky on the landing." Your definition considers total mission failure, from a less lucky missed landing, an acceptable risk. For whatever reason, you choose to disregard the fact that using an RTG would have eliminated that risk altogether, *and* it would have eliminated that seven month blackout period.

Comment Re:Not nuclear fear (Score 2, Informative) 419 419

RTFA.

The probe as built contained solar panels massing a little over 12 kg, and the plan depended on a perfect landing to get maximum solar exposure. Imperfect landing -> bad solar angle -> not enough power -> probe dead for seven months.

The RTG and support stuff would have massed about 12 kg and would not have required the perfect landing.

TL;DR - The RTG would have weighed the same as the solar panels, in a considerably smaller physical envelope, meaning it would have been EASIER AND CHEAPER to include an RTG.

Comment See how it is already done (Score 1) 257 257

You appear to be in the UK, so I'll suggest you check with the Ministry of Defence and get a list of UK defence manufacturers that build software-intensive systems with long life cycles. You're looking for things like airplanes and boats. Then write a NICE letter to those manufacturers and ask them how they do it.

The military routinely deals in systems with very long life cycles and many software upgrades.

As one example, the American F-16 first flew in the late 1970s. It is expected to continue to fly well into the 2020s. That's half a century.

The American B-52 first flew in 1952. They're STILL flying, and it is not unusual for a pilot to fly the same airplane his grandfather flew. (Flying his father's airplane is routine.)

You might also consider querying NASA in the US. They routinely launch deep-space missions that will take years, even decades, to reach their destination, and require software upgrades while in flight. For obvious reasons, it is not feasible to upgrade or replace the hardware on a probe out around Saturn's orbit, while it is on its way to Neptune.

Comment Re:so what you're saying is (Score 3, Insightful) 639 639

The word you are looking for is "calibration".

The phenomenon you are describing is called "system-wide consistent calibration error".

The problem with claiming that you have corrected a system-wide consistent calibration error is that you really need to explain how you managed to screw up the sensor calibration in the first place, on all of the ocean buoys, in such a way that they all had the SAME wrong readings.

Comment Re:not the real question (Score 4, Informative) 200 200

The corresponding FAA term is "Airworthiness Directive" (AD). An AD is a very big deal.

The in-flight entertainment (IFE) systems receive navigation data from the flight deck computers so they can display the moving maps and other stuff on the entertainment displays, for those passengers who want to know "where am I", "are we there yet", "is it time to reset my watch because we've crossed a time zone and I'm trying to adjust my body clock".

I would be shocked to learn that Boeing allowed the IFE to put ANY kind of data into the flight deck computers. I'd actually expect Boeing to use a one-way interface, one that transmits but does not receive: think RS-232 with one of the pins removed. I'd be almost as shocked to learn that Airbus did something like that. However, Airbus's comment about "firewalls" does not exactly inspire me to confidence in their airplanes.

There's something else. If Mr. Roberts did in fact do what the FBI claimed he said he did, I would have expected the air up in the cockpit to have turned very blue, as the pilots said (screamed, actually) something along the lines of what the Apollo 8 crew said (screamed, actually) when their CSM did an uncommanded thruster burn. I would further expected them to take manual control immediately, get on the radio immediately, declare an emergency because of the uncommanded engine power setting change, and land at the nearest airstrip that could handle the airplane. I would further expect maintenance crews to pull the flight data recorders to find out WTF just happened.

Comment Re:Homeland Security FTW! (Score 1) 94 94

Using a drone would be an easy way to deliver an explosive device to someone.

The phrase you are looking for is "cruise missile".

You can deliver much nastier things than explosive devices.

Weaponized anthrax comes immediately to mind. Or VX. Or quite a number of things.

For real nastiness, you'd use something like smallpox. Or a modified influenza.

Comment A few thoughts. (Score 5, Informative) 115 115

Lego Mindstorm comes immediately to mind, as it gets you DOING things with robots rather than getting bogged down in implementation. (The informal motto of the Dallas Personal Robotics Group at one time was "It's harder than it looks!", and they weren't kidding.)

Heathkit keeps talking about making a comeback, but I'm in an "I'll believe it when I see it" mood these days.

Ramsey Electronics has a LOT of kits. Most of them require basic soldering skills. However, they do sell some electronic experimenters kits, that don't require soldering.

Comment Re:stopping who? (Score 2, Informative) 322 322

And, yet again, that is PRECISELY what happened when Eisenhower signed the Nuclear Test Ban Treaty with the Soviet Union.

We knew IMMEDIATELY when the Soviets abrogated the treaty. They set off a whole slew of very dirty atmospheric test shots.

The treaty DIDN'T stop them from doing the tests.

Fear of detection of their cheating DIDN'T stop them from cheating.

Comment Timex Ironman Triathlon 200m digital watch (Score 1) 702 702

I just retired a Timex Ironman Triathlon 200m digital watch. It was time for a battery (at least its third, possibly its fourth), when I noticed that the Mode button had failed. (I never use it as anything but a watch these days, having pretty much given up diving.) That watch was easily 15 years old, and had been at least 100' underwater (wreck diving off North Carolina).

That watch was the cheapest diver's watch you could buy, by a big margin. Timex was very careful NOT to call it a diver's watch, because of product liability concerns, but IN FACT that's what it was and a lot of people used it for diving. (On their 50m and 100m water-resistant models, Timex very carefully said that the water resistance was guaranteed only as long as no buttons were pushed, and they very carefully did NOT say that for the 200m models. That language has since changed.)

Comment I Must Have Missed Something (Score 1) 50 50

I looked at the slideshow on the LISI house site, and I don't see anything that looks like a kitchen, anything that looks like a bedroom, or anything that looks like a bathroom.

Yes, they made a pretty space, but I do not see how it is a space for people to live, and I thought that was the purpose of a house, to be a space for people to live.

Comment Re:That's awesome (Score 1) 372 372

VERY old news.

When "Star Trek" first came on the air, in the 1960s, the US Navy sent a team to visit the set. They were building a new communications center, and they REALLY liked the bridge set layout, as it did an OUTSTANDING job of facilitating communications among the bridge crew.

Comment Re:Hope they pay close attention (Score 2) 132 132

Yup.

NOBODY wants to talk about this one.

Extract all the energy from the wave, and you have no more wave. There is a HUGE amount of shoreline and shallow-water marine ecology that is critically dependent on wave action. Remove the waves, and you wreck that ecology.

The Environmental Impact Statements for those wave energy plants are gonna be INTERESTING.

"Everything should be made as simple as possible, but not simpler." -- Albert Einstein

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