MedEwok wrote:
What I referred to is “lifetime probability”, how likely it is for something unlikely to happen in your lifetime. It’s 1:n for a given probability, but should be (1:n)*(1:n) for the probability of that event repeating (only applicable if said events cannot influence each other in some way)No, it’s not….
Assume that you throw dice twice in your life (unlikely, but for the sake of argument) and want to not get a six either time. (In this example getting a six corresponds to having an engine failure.) You throw the dice once and you do indeed get a six! Bad luck! Now, does that in any way affect the probability of your getting six the next time? No!
Similarly any other random event happening — like an engine failure — in no way affects the chance of that happening to you again.
This of course assumes that the events are entirely independent.
Your dice example illustrates my point perfectly. The chance is 1/6 each time but the chance of getting a six twice in a row is in fact (1/6)*(1/6) = 1/36
My error might be ignoring the fact that all the time you don’t get an engine failure makes up the rest of that, so all the 1s to 5s you get in between. So my point only stands for subsequent flights/dice rolls.
MedEwok wrote:
So my point only stands for subsequent flights/dice rolls.
I’m not sure I understand what you mean, but the fact that you once rolled a six (or had an engine failure) in no way affects your chance of rolling a six again (or having another engine failure) in the future.
It is true that it is very unlikely that you will experience two engine failures — but only as long as you don’t have the first one! As soon as you have had one engine failure, your chance of experiencing multiple ones (including the first one) increases dramatically.
It is true that it is very unlikely that you will experience two engine failures — but only as long as you don’t have the first one! As soon as you have had one engine failure, your chance of experiencing multiple ones (including the first one) increases dramatically.
I must be thick because I don’t get that 
Who is “you”? What if I rigged up a TB20 with remote control and with me not in it, it got an engine failure. Does that mean that when I am in it, the chances of me getting one are higher? How can they be higher, when I was not present for the one which happened?
Obviously, in practice, an engine failure is likely to be due to something the pilot is doing. Not necessarily “mismanagement per the POH” but any different operating profile can potentially affect engine reliability. It is a somewhat similar argument to the one where flying without a valid license or medical makes you more likely to crash, due to the “different attitude to doing things correctly” factor. People with a “live and let live” attitude will have more accidents. But that is a different debate; not a purely statistical/mathematical one.
Peter wrote:
Who is “you”? What if I rigged up a TB20 with remote control and with me not in it, it got an engine failure. Does that mean that when I am in it, the chances of me getting one are higher? How can they be higher, when I was not present for the one which happened?.“You” is however is operating the aircraft.
The probability of an event that has already happened is 1. Before you start throwing the dice, the probability of getting two sixes is 1/36. If you got a six the first time, the chance of getting two sixes increases to 1/6, since you already got one.
I understood MedEwok as arguing the other way — that the probability would decrease.
Obviously, in practice, an engine failure is likely to be due to something the pilot is doing. Not necessarily “mismanagement per the POH” but any different operating profile can potentially affect engine reliability. It is a somewhat similar argument to the one where flying without a valid license or medical makes you more likely to crash, due to the “different attitude to doing things correctly” factor. People with a “live and let live” attitude will have more accidents. But that is a different debate; not a purely statistical/mathematical one.
I agree. In practice engine failures are not completely independent events. But that will only reinforce the argument that MedEwok (as I understood him) had it wrong.
I’d like to add one more aspect without getting too much into parenting advice (which I’m in no position to give, anyway, as I do not have any children at this point).
@LeSving is painting an absolute picture where it’s the parents’ obligation to keep their children from any risk – rather than taking a per case approach and evaluating the risk as good as possible (which will, of course, in real life never be statistically correct, as there are always too many complex factors involved). Between the line, there is the notion that any parents who expose their children to risks such as GA overwater flying (or, for that matter, similarly risky activities) are somehow bad parents.
I strongly disagree and I think it’s a very subjective matter. Especially @medewok has displayed a great deal of thought and consideration by having and encouraging this very discussion – whatever the outcome.
If you want to raise your kids to maybe become the more successful players of their generation (leaders, people who inspire other people, who dare, who will some day in their life do great things, become great entrepreneurs, maybe save the planet, whatever…) you don’t encourage that by over-guarding them. Within limits that seem sensible to you as a parent, in my view, you need to expose your kids to a certain level a risk, and risky activities. And yes, you will have to make that decision for them to some extend, until they’re old enough to decide for themselves. Of course, if you want your kids to become couch potatoes who don’t risk anything, that is also fine and fair. But it’s not the only and not the only “right” way to raise children IMHO.
Again, all that coming from someone who IS someone’s child but who doesn’t have any, so who am I to judge.
If you want to raise your kids to maybe become the more successful players of their generation (leaders, people who inspire other people, who dare, who will some day in their life do great things, become great entrepreneurs, maybe save the planet, whatever…) you don’t encourage that by over-guarding them. Within limits that seem sensible to you as a parent, in my view, you need to expose your kids to a certain level a risk, and risky activities. And yes, you will have to make that decision for them to some extend, until they’re old enough to decide for themselves. Of course, if you want your kids to become couch potatoes who don’t risk anything, that is also fine and fair.
I couldn’t agree more.
Get a life raft, brief the passengers, and get on with the flight
I tend to agree re the children point. I flew my baby daughter over water and don’t consider myself a bad parent.
My concern with MedEwok’s flight is the combination of these factors.
As I said, it is perfectly doable but just be careful not to load too many different issues onto yourself.
Pardon if this has been suggested (haven’t read the whole thread yet), but you could cut the longest overwater leg to 20 NM (Sandhammaren lighthouse to to Hammerodde lighthouse) by going via Sweden. It would be a 315 NM trip via MIC, EKMB, EKRK, EKCH, ELM, etc. That is the sort of choice I made when I was getting my “feet wet” with this sort of flying.
Speaking as a VFR pilot with overwater experience, I feel that weather is a bigger risk to you than the possibility of an engine out during short overwater stretches. (I prefer not to take the family over cold water for hours at a time, but would not consider these stretches high risk in a plane I knew.). Make sure you’re comfortable in low visibility (de facto IMC) flying prior to the trip.
This looks like a trip made for GA. A Cessna 182 might be a good choice (I even know of one that might be available for rental in north Germany).
You have plenty of time to get used to whatever plane you choose before the trip. It could work out well and smoothly executed would show you and your wife what can be done in a light plane.
Trips alone to the Frisian Islands would be a great way to get confidence and experience up.
(As I read the thread, I see each of these points HAS been made. I add my voice to the chorus!)
In discussing Risk Management, let’s not forget what you give up by NOT TAKING the risk. I am not reckless, but I don’t forget the reward. To increase the chances of upside, I’m quite careful. But I suspect people often get fixated on the wrong risk.
You could also fly the family to a ferry port and do the overwater leg yourself. If it went well and the weather were good, you could all come back together.
I often do these trips mixing commercial and GA flights, or propositioning the plane. But the distances involved here are moderate and don’t require that.
