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Thread: Tertiary back up

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    Tertiary back up

    So, here I am, sitting here searching the internet for a decent secondary flashlight while simultaneously wondering what factors should be considered when designing back up systems for space flight. Talk about split focus!

    First, a few terms: “primary,” “secondary,” “tertiary,” and “quaternary”: first in order, second in order, third in order, and fourth in order. You’ll noticed I used “tertiary” in the thread title and “secondary” when describing the flashlight.

    In principle, even if not always in practice, I have respect for the mindset for having backup. If you go on a camping trip, you’ll likely carry a lighter to start a fire. That’s your primary go-to to get that blaze of warmth started. Awe, but what if it gets wet and will not start? This is where back-up comes in!

    Yes, you could have another (yet dry) lighter, and yes that could stand in as back up, but what about some wet-resistant matches as your secondary “go-to” in the event your primary automatic source fails you! In this case, your so-called back up plan would not really and truly be your secondary back up. In this case, your entire pack of lighters you bring can all be labeled your primary ignition source whereas your matches (both boxes, lol) will be your secondary back-up (your plan B, as some say).

    Many moons ago, I heard of “triple redundancy” while listening to something about avionics. It’s essentially a back up for when your back up fails. If all my lighters fail, and if all my matches fail, then surely I can turn to plan C and initiate operation magnesium stick! It’s a handy little gadget that can moderately easily be utilized to get a fire going—especially if it isn’t windy—thought i’d throw that in there.

    But, recall my opening sentence. There are factors to consider. If you’re on a canoe and it flips, please don’t tell me you put your primary, secondary, and tertiary fire starting tools in the same damn bag that just got swept down the river, as I promise you, whether or not you have suffiently practiced enough to put your lousy quaternary plan in effect (you know, the one that requires rubbing sticks together), it’s not going to be as easy in the bush as it is in your back yard.

    Separate. Isolate. Keep apart. When you go out on your boat and your motor dies, be glad you have a trolling motor (and a separate battery to boot) to keep moving in the direction you have control over rather than drifting where you’d rather not. When you’re traveling from Mars to Venus in search of a woman that won’t lie to you, be glad your onboard mega-mighty computer 3000 isn’t also controlling your ability to breath, no matter whether there are integrated back-up systems. See, back up of the same kind or from the same source of power and control isn’t very diversified to combat the whole dang point of having back up.

    Me, personally, I’m happy with three’s. If I have three flashlights in my vehicle, that’s good enough. No, I’m not going to have candles and lanterns. If I had an underlying back up system for everything I can have a back up for, i’d need an 18-wheeler to haul it all. But, back to the notion of pure back up (but of the same system), I do tend to prefer that the tertiary back up (be it multi-functional or not) have a predetermined multi-use. In my case, my go-to light is my primary light—and my go-to is my secondary if my primary goes out. If it’s night and I’m with someone, and we’re both in need of a light, I have my primary for me and a secondary for the other party.

    I know. I know. If it’s you and you have three lights, you’re just gonna grab whatever one is handy. That’s all fine and good, but for my third flashlight, I need for it to have a creative multiuse. Guns, knives, pipes. They’re all either weapons or non-weapons considered as such, but many items aren’t generally called a weapon by either group until something is used as a weapon. That’s when one of those four D-cell stainless steel mag-lights come in. To one, it’s a flashlight that can be used as a weapon, but to another, it’s a it’s weapon that can be used as a flashlight. A broken TV can be used as a door stop, and though it’s a TV, it’s broken, and it’s current use is clear.

    What other factors belong on our “think it through” list?

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    If you think it too much you might conclude going camping is a really bad idea. Ever watch the TV show Dual Survival? There was one survivalist who you could drop off most anywhere and he would make fire, a good shelter, and eat well.

    It is all probabilities. An extra flashlight may be a good idea. A little lighter fluid and a steel-flint spark combo works well.

    One thing you do not want to do is go without a map and compass. I knew someone who went biking in the Cascades mountauns and got lost as the sun went down. No map or compass or survival kit. In the winter in my jeep in snow country I always had a sleeping bad and food. When day hiking I always carried a space blanket.

    The Boy Scout motto, Be Prepared.

    The Space Shuttle had 3 redundant computers.

    As to designing redundancy, it is all probabilities. Statistically as you add more redundancy reliability can actually go down. A lare commercial jet with two engines will have gebrators on each engine and a battery back up. Some will have a tyrbine engine for elctricity, you can see the exaust post on the tail.

    I know of one case in the 90s where on a commecial jet both engine generators failed, the battery failed so the backup turbine could not be started. Fortunatly it was nit fly by wire and had cables from the cockpit to flight surfaces and throttles arenusally mecanical.
    Last edited by steve_bank; 08-27-2019 at 09:44 PM.

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    Quote Originally Posted by steve_bank View Post
    If you think it too much you might conclude going camping is a really bad idea.
    That’s right, but I’ll come around and remember this line from the pilot for MacGyver: The bag's not for what I take, Colson - it's for what I find along the way."

    With all the items in the world, it’s hard to beat preparation of the kind that includes head knowledge.

    As to the shows, watched em and lived em—but not necessarily in that order.

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    Quote Originally Posted by steve_bank View Post
    As to designing redundancy, it is all probabilities. Statistically as you add more redundancy reliability can actually go down.
    You mean like a fancy car — with more parts so more can go wrong

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    The latter. The more parts you add at some point reliability goes down/

    An old textbook problem. On a plane you star out with a single engine, then two engines, then four and so on. At some point reliability gets worse.

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    Quote Originally Posted by steve_bank View Post
    It is all probabilities. An extra flashlight may be a good idea. A little lighter fluid and a steel-flint spark combo works well.
    I definitely agree on light sources. In the winter I sometimes hike at night--always with at least two light sources. I've seen a night hike posted that explicitly stated to bring at least two light sources. Around here, though, I don't pack any source of fire--I can't picture a scenario where it would be of benefit. If I'm caught in conditions where I need fire for heat I would be amazed if it's not too windy. (Now, if I were doing overnight trips it would be different--I would have an ignition source for a stove.)

    One thing you do not want to do is go without a map and compass. I knew someone who went biking in the Cascades mountauns and got lost as the sun went down. No map or compass or survival kit. In the winter in my jeep in snow country I always had a sleeping bad and food. When day hiking I always carried a space blanket.
    If the sun goes down that compass isn't going to be of any use. Were I in snow country I would definitely agree with your vehicle preparations. There are two space blankets in the emergency gear that's in my pack.

    As to designing redundancy, it is all probabilities. Statistically as you add more redundancy reliability can actually go down. A lare commercial jet with two engines will have gebrators on each engine and a battery back up. Some will have a tyrbine engine for elctricity, you can see the exaust post on the tail.
    Definitely an issue when hiking. The more redundancy in your gear the heavier your pack and the less mobile you will be--more likely to not be able to avoid a bad situation.

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