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Questions People Ask When I Tell Them I Own an Airplane

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Re: Questions People Ask When I Tell Them I Own an Airplane

#201

Post by maxcan »

lutorm wrote: post #156
maxcan wrote: post #113

Earlier quoted context omitted.

I think in the past, aircraft engines were relatively unreliable and would often quit midair for reasons other than fuel starvation so there'd be some chance of the other engine saving you. Now, however, almost all engine failures are the result of fuel starvation and two engines will die just as quick sans fuel as one so the added complexity isn't quite worth it, from a safety perspective for piston powered aircraft…

Why do you say the turbine situation is completely different? Turbine engines are if anything more reliable than piston ones.

Sorry, I meant different in that I know very little about it. My language was imprecise.

With turbo{fan|jet}s I think there is an issue that its just difficult to construct aircraft with a single engine as opposed to wing or tail mounts.

Re: Questions People Ask When I Tell Them I Own an Airplane

#202

Post by ZoFreX »

rsync wrote: post #96

Here's a question: Tell me about single engine (what you appear to have) vs. multi engine (twin, I guess) ? Should I be thinking about redundancy in plane engines the same way I think about redundancy in ... say ... kidneys ? It seems to me that I would really, really want a twin engined plane... edit: I found this [1] but I'm not sure I buy it. I am all about simplicity in systems, but redundancy in a critical compo…

Most common question I got when I flew: "What do you do if the engine stops?"

My answer: "Turn around go home and land"

It does help that I started out on gliders (sailplanes) first, of course... but losing the engine really isn't that big a deal in level flight in many small aircraft (or even big ones actually - a 747 has a surprisingly decent glide ratio (not actually surprising if you think about it, tbh)).

I've never flown twin engine, but as others have mentioned, losing one engine in a twin can be catastrophic - unless it's the Boomerang of course ;) http://en.wikipedia.org/wiki/Rutan_Boomerang

In summary: I would choose zero engines, one engine, or four engines - but not two.

Re: Questions People Ask When I Tell Them I Own an Airplane

#203

Post by sanoli »

nathanstitt wrote: post #177
jcoby wrote: post #159

Earlier quoted context omitted.

True. Or they bought the plane 20+ years ago and still own it. When I go to EAA meetings I'm the youngest by 15-20 years and I'm in my 30s. I don't think I've ever seen a privately owned certified plane that was newer than 25 years old. It's all around a bad situation for general aviation.

Same here. I'm in my late 30s and am by far the youngest at any pilot gathering I attend. I really don't know where the airlines are going to get the next generation of pilots from. Of course with the horrible pay and hours, I can't blame anyone from not choosing that career path.

Maybe from overseas (mainly developing countries?). I don't know for sure, but I know some pilots from here (Brazil), including my cousin, who went off to fly for chinese and mid-eastern airlines, because the demand was high over there. Maybe the US won't be so far off?

Re: Questions People Ask When I Tell Them I Own an Airplane

#204

Post by sanoli »

existencebox wrote: post #200
nathanstitt wrote: post #177

Earlier quoted context omitted.

Same here. I'm in my late 30s and am by far the youngest at any pilot gathering I attend. I really don't know where the airlines are going to get the next generation of pilots from. Of course with the horrible pay and hours, I can't blame anyone from not choosing that career path.

Maybe I'm being a bit far fetched here, but what if someone up in management is banking on "phasing out the pilots." Autopilot has for a long time been "good at some things", and there's often debate here as to what purpose a human pilot increasingly does or doesn't have in the cockpit as the computerized solutions become more reliable. As there are fewer pilots, relegate the physical role to a babysitter; potentiall…

Pilots on todays big airline planes are pretty much babysitters to the autopilot. Still, it will be a long time untill the notion of flying a plane with no pilot is accepted by the public. Even though it will probably be safer, as you're taking a chunk of human errors out of the equation.

Re: Questions People Ask When I Tell Them I Own an Airplane

#205

Post by skybrian »

mcdougle wrote: post #111

I've been toying with the idea of getting my pilot's license (eventually) partially for the sake of avoiding the TSA when I actually have to travel. What I'm curious about is how difficult/expensive it is to rent a plane that can fly further than stated in the article? (say, TX to CA, for instance) I imagine it wouldn't make much sense to buy a huge cross-country jet for the occasional long trips, although I am kind…

That range is just the distance you can fly without stopping to refuel. Multi-stop trips can certainly be longer than that, if you have the time.

A faster plane will get you there quicker, of course, but they are also much more expensive and harder to fly.

That price is for a rather old used plane; newer planes cost much more. Some flying clubs have a variety of planes to rent, though you need to reserve them and more importantly learn to fly them.

Re: Questions People Ask When I Tell Them I Own an Airplane

#206

Post by cpncrunch »

mcdougle wrote: post #111

I've been toying with the idea of getting my pilot's license (eventually) partially for the sake of avoiding the TSA when I actually have to travel. What I'm curious about is how difficult/expensive it is to rent a plane that can fly further than stated in the article? (say, TX to CA, for instance) I imagine it wouldn't make much sense to buy a huge cross-country jet for the occasional long trips, although I am kind…

First of all, you can buy a perfectly safe and airworthy Cessna 150 for around $15k, and you could fly it from TX to CA - it would just take quite a long time, and probably be quite bumpy. You might also get stranded for a few days half-way while waiting for weather.

To fly long cross-country trips in comfort you really need something like a Cessna 182, or even better a Cirrus or a light twin. You'll end up spending at least $100k for well equipped IFR plane (and you'll need an instrument rating). Ideally you'd want oxygen, turbos and deicing so you can fly above/through the weather.

So, in summary, it's not really feasible to buy a plane for personal transportation across large distances unless you want to spend a lot of money. You just can't beat the airlines in terms of value for money, safety and reliability, even if it is a miserable experience.

Re: Questions People Ask When I Tell Them I Own an Airplane

#207

Post by sanoli »

lutusp wrote: post #199
Tossrock wrote: post #194

Earlier quoted context omitted.

That is not how a binomial probability is calculated. Consider the case where you flip a coin twice - do you have a 2 * 1/2, or 100% chance of getting a 'head'? Obviously not – you have a 75% chance. The actual way you calculate the probability of an event with a binomial distribution is by taking the inverse probability and raising it to the power of the attempts, then subtracting from 1. So in the case of two coin…

You certainly deserve my upvote. :) You set out to correct a naive statistical assumption, computed it properly, and the result was about the same (not at all common for such problems). But you posted it anyway, in the spirit of sharing useful information. As the Australians say, "Good on you, mate."

I second the upvote. This is exactly the awesome part of HN.

Re: Questions People Ask When I Tell Them I Own an Airplane

#208

Post by aaronsnoswell »

malandrew wrote: post #170
lutusp wrote: post #2

It's important to say that the general aviation population has gotten much smaller over the last few decades. It was a lot more popular 25 years ago when I flew much more than I do now. A number of aircraft manufacturers have stopped building small general-aviation planes for a number of reasons including liability and a reduction in public interest. I started flying about 1980. By 1992, 12 years later, about half th…

Whoa! really? I never imagined that deaths were that frequent. What were most of the causes of the accidents? Operator error? Poor conditions? Equipment failure? Has the rate of people dying off fallen as the equipment (planes and instruments) has improved? I had always assumed the decline has more to do with the economics of the sport and the amount of upfront investment necessary to get to the point where you can f…

In the 1950s, test pilots were dying approximately once per week [1].

[1] http://en.wikipedia.org/wiki/Test_pilot

Re: Questions People Ask When I Tell Them I Own an Airplane

#209

Post by vilhelm_s »

Tossrock wrote: post #194
vilhelm_s wrote: post #168

Earlier quoted context omitted.

How do you mean? The suggested calculation is: In any given year, a motorcycle owner has a 72/100000 chance of dying. So if you own a motorcycle for 30 years, the chance of dying is approximately 30*72/100000.

That is not how a binomial probability is calculated. Consider the case where you flip a coin twice - do you have a 2 * 1/2, or 100% chance of getting a 'head'? Obviously not – you have a 75% chance. The actual way you calculate the probability of an event with a binomial distribution is by taking the inverse probability and raising it to the power of the attempts, then subtracting from 1. So in the case of two coin…

That's why I said "approximately". :)

By the binomial series [1], the true value is 1-(1-p)^n = np - n(n-1)/2! p^2 + n(n-1)(n-2)/3! p^3 + ...

So approximating it to just np corresponds to taking just the leading term of the series. Of course, this is only valid when p is small enough. To see how good the approximation is, we can compare it to the two first terms of the series, which is np - n(n-1)/2 p^2, or approximately np - (np)^2 /2.

So the approximation np is about twice the percentage difference between the approximation and the true value. In this case, the approximation np is about 2%, and that guess is itself about 1% wrong.

[1] https://en.wikipedia.org/wiki/Binomial_series

Re: Questions People Ask When I Tell Them I Own an Airplane

#210

Post by mercutio2 »

sokoloff wrote: post #124
mercutio2 wrote: post #120

Earlier quoted context omitted.

Where do you get 4.1% inflation from? CPI for the USD hasn't gone up by that much in a single year for the last decade, annualized inflation is closer to 2.5% over that period.

4.1% is the 10th root of 150% minus 1. "OMG, this cost went up 50% over ten years!" sounds like a dire situation, when in fact it's a tiny margin over whatever inflation measure you prefer. If you take 2.5% as the annualized inflation, that's 28% over that 10 year period, meaning the other 17% increase is 1.6% "real dollar increase" per year. Hardly frightening, IMO.

Ah. I interpreted your statement as "we had 4.1% inflation in the last decade". Your intent was "it's as if we 'd had 4.1% inflation, not much more than actual inflation".

I completely agree that nominal gas rates aren't the right measure, and the real price increase has indeed been tiny.

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