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Comment Re:Potato gun (Score 1) 251

I didn't think I had a story here, thanks for reminding me of my potato cannons!

In my intro to electronics course we had taken the flash circuits from disposable cameras and hacked them to trigger via a photocell.

I had another idea: take the ~300v from the flash capacitor, dump it through a car ignition coil then through a spark plug, and I'd get a much more reliable spark than could be had by a piezo grill igniter. My best guess is that I had a few hundred thousand volts at the spark plug. I put everything in a small plastic Radio Shack project box, put a button on each side, and wired the buttons in series to prevent accidental discharges.

It worked very well: in ~5 years of use I think I went through two C cells and it only failed to work when the first battery died. Whenever I'd show off my handiwork, my audience was invariably more intimidated by the sound of the circuit charging up than the actual potato cannon :)

Comment Re:Actual *real pilots* discussion on another foru (Score 1) 268

Sure, and how much does it cost to store the thing, to have it launched, and do whatever else has to be done with a glider? I know powered aircraft are often white elephants in that respect.

Much less than a powered aircraft. Gliders generally disassemble and are stored in trailers; maintenance is limited to the annual inspection, washing/waxing, repairs, replacement of wear components, periodic repacking of your parachute if you wear one, um... I'm sure I'm missing something. One of the big expenses is just non-existent: there's no powerplant to maintain! Launching fees vary widely, but they start at ~$5 for a winch launch. Flights can be as short as 5 minutes or upwards of 5 hours, depending on conditions, endurance, and skill. Insurance isn't free, but it's certainly not prohibitively expensive.

I don't have a day a week to train so I could legally (under the sort of regime being proposed) fly my model aircraft. And they'd cost that same $10k-$20k once all the proposed equipment to do things like respect NOTAMs and restricted areas is put in. Because no one would make such equipment for hobbyists, they'd make it for the commercial market.

Most of the FAA's regulations actually make sense, and the licensing requirements for different categories of aircraft / licenses call for different levels of training - flying an ultralight doesn't even require a license (but the pilots are still responsible for following the rules). I would suspect that a drone rating would be a simple knowledge test, and there would be no practical exam since so much of a drone's flight is automated - it might even be something you could self-study for. Obtaining the required number of flight hours, and otherwise preparing for the practical is what constitutes the lion's share of the time/money needed to get a private/light sport/recreational license - you need to know, for example, what causes stalls and how to recover from them. I suspect the exam would cover things like airspace definitions and rules, right-of-way rules, etc.

Comment Re:Actual *real pilots* discussion on another foru (Score 1) 268

On the contrary, a lot of people want draconian restrictions like mandatory licensing and restrictions on sale of such vehicles.

Perhaps I misspoke. I should have said that I've not heard from anyone who wants this, and I have talked about it with other pilots.

except relatively wealthy ones with a ton of time, like yourself

Your assumptions are showing.

While there are wealthy pilots, most of us are of modest means. My (small) car is paid off so I spend the equivalent of its payment on my hobby during the on season, and that amount will go down once I finish my license. I won't need to buy my own glider outright, but if I do decide to do so, there are perfectly adequate specimens for sale in the $10k-$20k range.

As for time, I fly one day per week - sometimes two, sometimes zero. On the days I do fly, I still have time to mow the lawn, cook dinner, work on household projects, and even watch a movie with family.

Comment Re:Actual *real pilots* discussion on another foru (Score 1) 268

Student pilot here, you're wrong. I fly for a hobby and will never earn a living doing it so I have no fear of lost income, but drones are scary because they could kill me. The thought of a quadcopter popping up in front of my flight path on short final is scary indeed - there's already plenty to think about without worrying about that.

Like anything, flying is a calculated risk and I accept the odds, the recent proliferation of cheap drones just makes it a bit riskier. It's not so scary that I'm going to stop, but I would like some kind of formalized rule to mitigate it. Nobody wants draconian restrictions like mandatory licensing, but Joe Sixpack oughtn't try to take a close-up video of my landing without discussing it with me beforehand (link).

OP is correct, there is no good solution apparent.

Comment Re:Tabs vs Spaces (Score 1) 428

so why not stick with tabs which are more flexible, configurable etc?

Because indentation isn't just for code blocks. I can't stand method declarations with lots of parameters lumped together on one line with a single space between them; it's so much more readable to put one parameter per line. Calling these methods is a similar issue, it's unreadable when all the parameters are lumped together. Long expressions are another example.

Now to get everything aligned, you need to use a mixture of tabs (to begin the next line at the correct indent level) and spaces (to left-align the item). It's certainly do-able, but it's a break in your concentration. Then two weeks later someone else fixes a bug in your code and changes the spacing to tabs-only for their portion of the code, and the very next day someone else ... you get the idea.

Spaces remove this ambiguity, and it makes it easy for my less-meticulous co-developers to align things properly.

Comment Re:Run your own equipment (Score 3, Insightful) 96

I did this quite recently and I couldn't agree more!

After my Linksys started dying on a regular basis, I repurposed an old laptop that had been sitting untouched for years into an OpenBSD router. After fiddling with it for a while to get the settings correct, I switched out my old Linksys and haven't had so much as a hiccup since then. The 26 days uptime is ~19 more than my average with the crappy old Linksys, at the cost of a bit more power consumption. At some point I may upgrade my hardware to something lower-power, but so far I'm calling my experiment a sucess.

Comment Re:It won't be long (Score 1) 325

The only thing different about drones is that they are slow and hence easier seen.

No, absolutely not! Motion is much easier to see. Consider a deer; hard to spot when it's standing still, much easier once it starts moving.

The easiest way spot other aircraft when I'm flying (did I mention I'm a student pilot?) is because of their apparent motion against a (usually contrasting) background. When birds or other aircraft are at the same altitude as me they appear just about on the horizon, and they're much harder to spot. Even gliders with 15-18 meter wingspans are tough to spot when they're at the same altitude - in fact, head-on collisions is a big safety issue that can even trip up top glider pilots ( - the description on page 1 is particularly enlightening, and the graphic on page 3 shows the relative size of gliders relative to the time left to react). Drones are small and seeing one directly in front of me would NOT be easy.

There is zero new risk here and history shows that there is zero actual risk in this as nobody ever brought down a commercial airliner with a model airplane or helicopter. AFAIK it has not even been tried, ever.

The problem with this argument is that traditional model aircraft pilots didn't have cameras on their planes/helis. Now that drones come with them pre-installed, their pilots can fly at much longer range and without direct line of sight - traditional model aircraft pilots need to constantly watch their aircraft to keep it under control. Imagine the difficulty of hitting a target when your R/C heli is a few hundred feet away. Then imagine using an onboard camera to watch your target approach.

Now if you'd said that laws wouldn't prevent a terrorist from doing this, I'd agree with you. If you'd said that an outright ban on drones is unreasonable and untenable, I'd agree with you. I'd have even agreed if you'd said that the chances are slim of a terrorist actually using a drone maliciously. Where I strongly disagree is saying that the threat level hasn't changed. Technology has made drones more readily accessible and easier to pilot in a malicious manner, one need only look at the increased reports of near misses to realize that the number of drones being flown recklessly is increasing.

Comment Re:Birds (Score 1) 115

Birds may be heavier, but the various pieces of the many types of drones are harder and sharper; I don't know how you can say with such certainty that birds are more dangerous. Do you have any evidence to back up your claim? I know of no studies regarding drone strikes, let alone comparing them to bird strikes.

Also, birds are animals and can't really be regulated. People are - in theory at least, I'm beginning to doubt the practical applications - smarter and ought to know better.

Comment Re:Avionics (Score 1) 115

I know it would add cost but as someone else said why doesn't the FAA require a license and transponders on drones so that everyone knows what's in the air and who owns it?

With identity information, you're talking about a mode S transponder. These things are more expensive than you probably think.

Also, because the USA is really big, and (lesser, mode C) transponders aren't even required for flying in most airspace: you need one in class A airspace ( > 18,000ft MSL), in or above class B & C airspace (near large airports, with larger radii at higher altitudes), in the mode C veil around class B airports (an even bigger cylinder around the biggest airports), and > 10,000ft MSL unless you're < 2,500ft AGL.

Simple, right?</sarcasm>

So basically, transponders are only currently required at higher altitudes and near large airports. ATC is simply too busy dealing with the current air traffic to handle the rest of the country's airspace.

Comment Re:How do they define a close call? (Score 4, Informative) 115

Background: I am a student pilot, with ~35 hours in power planes and ~20 hours in gliders.

Define a few feet please.

The FAA has this definition which seems especially relevant in this discussion.

And do pilots also report to the FAA everytime they pass "within a few feet" of a bird?

It's quite common for pilots to radio their controller when they encounter a hazard. That's how your pilot knows to turn on the "fasten seatbelt" light when you're approaching turbulence; the same goes for flocks of birds or unidentified aircraft. Even so, it's not really fair to compare birds drones, for the same reason that deer don't get jaywalking tickets.

I can say through personal experience that just seeing other aircraft / birds takes a huge amount of my attention, even when the other gliders have 15-18 meter wingspans. Drones are much smaller than manned aircraft and they tend to move very slowly, making them even harder to see. The problem of seeing other gliders is a big enough issue where someone developed a technology called FLARM to reduce the number of collisions by notifying pilots of other gliders within ~4km; it has already saved many lives despite being only 10 years old.

So when I'm flying, I spend a large amount of my time looking for other aircraft. My eyes have much better resolution and FoV than a drone's camera, and I can swing my head around to look from side to side, and up & down - this gives me a better capability to look for hazards. Birds also tend to have good eyes & ears. There is a very good incentive for us to be vigilant: our lives are at stake.

On the other hand, drone pilots only have a camera, hooked up to a low-resolution video screen, which they would need to aim all around in order to scan for other aircraft. The problem is magnified by the fact that have a poor incentive to look for collision hazards: they have a few hundred dollars at stake, and they're probably already using the same camera to look at something on the ground.

The FAA has been hell bent on gaining government control over drones and they will make up any excuse they can, the scarier the better.

Sorry, I just don't buy the regulatory overreach argument in this case. My life could be put in jeopardy by someone playing with their new toy while I'm already flying low and slow on final approach; the last thing I need is another distraction when I'll be touching down (one way or another) within 15 seconds.

I would wager that most of the people writing the regulations are pilots of some capacity, and those who aren't certainly have ready access to many extremely experienced pilots; these people are just trying to protect the lives of millions of airline passengers, flight crew, and pilots.

Comment Re:What? (Score 1) 55

My wife got a Nielsen survey this year. She obliged them by dutifully filling out the book, and near the end of the week I glanced through it. I was surprised that she listed me as having watched TV with her nearly every day, when in truth I had only watched about 1-2 hours of TV in the whole week, and that was on Netflix.

I'm not sure why she lied in the diary, but it certainly cast the Nielsen ratings in a different light for me.

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