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APenNameAndThatA

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Everything posted by APenNameAndThatA

  1. In this situation a bit if toxicity might help.
  2. Your are being too all-or-nothing about whether or not data has any value, and dumping the data just because it is imperfect. Take the comparison of death rates between car drivers and motorcyclists: most of the the fatalities might be from weekend riders and most of the kilometers might be from professional riders during the week (I don't know). That does not mean that the comparison is meaningless, it just means that you need to take that into account when you are deciding if buying a motorbike to ride on the weekend is a good idea. It is wrong to say that you cannot compare risks when someone rides for a certain amount of time, and fly for a certain distance. It does not matter what the motivation is. The further/longer you fly/ride/drive, the greater the risk. Simple as that. As for the idea that comparing distance based on speed being erroneous, it's not. LSA's fly in a pretty specific speed band. The issues of headwind are going to be smaller than the individual differences in LSA speeds. As all winds are headwinds, as it were, you could take headwinds into account by saying that there is, on average, a 5 kt headwind. It does not make a difference. If someone is wanting to work out how safe flying is, they can compare it to driving *or* riding a motorbike. If someone wants more accurate data, they can drill down and modify the *base rate* of risk by taking into account their hours, temperament, aircraft, weather and etc. ------------------- Let me say the same thing differently by asking you some questions. 1. In the light of the above calculation, what do you think the probability is that LSA flying is safer driving a car? 2. In the light of the above calculation, what do you think the probability is that LSA flying is more dangerous than riding a motorbike? 3. Before the above statistics were presented to you, did you have any idea if LSA was safer or more dangerous that driving? If so, what did you base your assessment on? Was the thing more or less reliable than the calculation above? 4. Do you have a better way of comparing the risk? If not, do you not have a clue how dangerous LSA is compared to travelling by car? As in, no clue? 5. It is generally accepted that travelling by commercial airline is safer than travelling by car. Do you accept those statistics? Why? Commercial airlines travel vastly greater distances vastly faster than car, by people who travel for different reasons and motivations, and less often, so how can you compare the risks?
  3. That is fascinating. The calculations that I had done in the past, when I was considering flying, were as follows. 1 fatal per 100 000 hours. That means that if someone flew 50 hours per year, there was a 1/2000 chance of dying per year. The base mortality rate for people who are about 40 or 50 is about 1/1000. Importantly, that includes people who were already *known* to be at risk, such as people with severe medical illness. I reasoned that if I flew, I would roughly increase the chance of me dying by 50%. As for flying with kids in the plane: their base rate risk of death was 1/2000, and they did not have a chronic illness. That means that, if you fly with your kids a lot, if they are going to die, it will probably be in your aircraft. Flying: it's not dangerous, but it's not safe.
  4. No, it's comparing probability of dying to probability of dying.
  5. There is simply no need to take into factors like weather or to scrub data for this kind of comparison. There is no need to remove any factors that might confound the data, because, as far as we know, the same factors will be present in the same amounts going forward. Stating the same thing differently, if we remove confounding variables then we would remove important factors that should not be removed. One way to manage financial risks of projects running over budget is to see how much similar projects tend to run over budget. It does not matter why projects run over budget, but simply that they do. If they tend to run 30% over budget, then that is what you can say will happen with the current project. Again, this is the opposite of scrubbing data. The following is actually a simple comparison, and not impossible at all: LSA’s fly at 90 kts, or 170 kph. On fatal per 100 000 hrs = one fatal per 17 000 000 km. 200 / 17 = 12. So, about 12 times more dangerous than driving, and about 40% as dangerous as a motorbike. If you want to make specific criticisms of the figures, then I am all ears.
  6. The way you tell the story, the farmer did not learn to drive faster than 15 kmph.
  7. I’m pretty sure that if you lose power on climb-out in a C172 you are supposed to lower the nose. Disclaimer: I have about 50 hrs.
  8. I think that people who would have flown Thrusters/Drifters now fly weight shift. I too looked at the cost of weight shift training, and it was very high.
  9. Those stats also mean that the faster LSA’s are the safer they are.
  10. Here’s some better maths. LSA’s fly at 90 kts, or 170 kph. On fatal per 100 000 hrs = one fatal per 17 000 000 km. 200 / 17 = 12. So, about 12 times more dangerous than driving, and about 40% as dangerous as a motor bike. That *does* make intuitive sense to me. I am not sure if those numbers need to take into account number of vehicle occupants.
  11. LSA's have a fatality rate of about 1 per 100 000 hours. I am assuming that cars have an average speed of 50 kmph. The reference is not super informative and the 50 kph figure might be the weakest point in my calculations. https://www.tmr.qld.gov.au/Safety/Road-safety/Road-safety-research-reports/Speed-compliance-and-average-speed-results#:~:text=Speeding%3A%20trends%20in%20posted%20speed,results%20from%202015%2D2018).&text=Average%20speeds%20of%20motorists%20on%2080km%2Fh%20roads,results%20from%202015%2D2018). Australia has a fatal car accident every 200 000 000 car km. Reference: https://www.bitre.gov.au/publications/ongoing/international_road_safety_comparisons#:~:text=In%20terms%20of%20the%20fatality%20rate%20per%2010%2C000%20registered%20vehicles,rate%20out%20of%2022%20nations. 200 000 000 / 50 = one fatality for 40 000 000 hours. Motorcycles are responsible for 1% of vehicle kilometers but 30% of deaths. Figures are in the the introduction to this PDF https://www.infrastructure.gov.au/roads/safety/publications/2008/pdf/mono20.pdf So, Motorcycles are responsible for a death every 40 000 000 / 30 ≈ 1 300 000 hours between deaths. Or, 13 times safer than LSA's. That does not sound right, but who knows. If you assume that the number of people killed per car accident is two, and the average number for motorcyclists killed per accident is 1.1 ≈ 1, then I can't work out what that does to the figures without thinking about it.
  12. The GA version is similar. I have no clue what the overlap is. Weight and balance is much more detailed in the GA version of the books, of course.
  13. They are all I studied. Conventional wisdom is that they are the best. If you have questions, you can get on the forums and ask. They are also available online of you want to study from your phone. That access is expensive and only lasts 12 months, but. There are occasional inaccuracies and the author does not like to be corrected (neither do I). For example, one of the first things the book says is that if you pull the stick back, the plane goes up. Given that pulling back if you are inverted is one of the main things that kills you if you are inverted, I thought that that was an issue. Not to mention that stalling is a safety issue too. If you learn the wrong thing first, it is hard to undo.
  14. Wikipedia says that the Sling 2 weighs 370 kg empty. It seems that if you use a lot of smooth it makes the aircraft more heavy. Aeroprakt A32 weighs 320 empty and cruise is 115 kt instead of 120, and does not come as a kit in the US anyway. My mighty Foxbat A22LS weights 345 kg (with parachute, big wheels and fuel injection) and cruises at a massive 80 kt. According to Aeroprakt, the A32 with big wheels is not faster than the A22LS, and big wheels are not approved for use with the A32. Air is funny stuff.
  15. Why no LSA?
  16. https://www.brother.com.au/en/products/all-labellers/labellers/pt-e550wvp I thought that some of you might be interested in this, as there was a discussion about labling wires. They say the wrap is legible after many hours at 150 deg C. Disclaimer: my engineering is I built a tree house.
  17. W Well, he does like his porsche, and his plane and his porsche and his plane, judging by the cinematography.
  18. Fun fact. At Archerfield, the radar return comes from the Class A Brisbane airport via the internet. That means that the radar return can be delayed up to 30 s. Here I was thinking that they were stopping me running into someone else!
  19. I am learning to fly at a Class D airport. My understanding it that a) the flying school needs to have the CASA stamp of approval, b) you need to have a CASA medical, and c) you need to be under the supervision of an instructor. That means that you can't turn up and fly if there is no one at the flying school to supervise you. and d) the airport is the one that your flying school is located at. After tower hours, you can fly with an RA-Aus licence, but then it's not really Class D anymore. You need a radio. I assume you need a transponder that encodes altitude. You do not need a certified engine (contrary to what someone told me, who should have known better.)
  20. I have an iS and an emergency power button on the dash. I was wondering what it was for. if alternator B fails, then won't alternator A keep the ECU and fuel pumps going. So, why would I need to restart if alternator A stops? I assume I misunderstood what you were saying. I have read the POH but it did not go into the emergency power button in much detail. Reference to read up on? Thanks!
  21. When I said colour I meant what the colour symbolised. When I said don’t change colour, I meant don’t change coolant type. If the convention is looser than I thought, then that was me being wrong.
  22. I drank a small amount of distilled water once and it tasted very acidic. I invite you all to try the same experiment. My understanding of why is that in, say, rainwater the other ions in the water buffer the H+ ions. But distilled water is so pure that the H+ ions are unbuffered and act like an acid. I have no clue about why, for example, the unbuffered OH- ions don’t make the water taste basic. This is me agreeing with pmccarthy. I am surprised no one has mentioned the obvious. Changing the colour of your coolant has little upside and a huge potential downside. You would have to be mad to even contemplate it. Disclaimer: 50 pilot; engineering qualification is I built a treehouse once.
  23. The performance figures if the aircraft are not the most important thing. Reliability and after-sales support are much more important. Perhaps your town has lots of one make, or the best flying instructor for Alps flying has a particular plane? Or there is a LAME that loves a particular make and that you can rely on them? The Sivannah is all aluminium (good) but I did not fit because of headroom (bad). The Foxbat A22 is the 450 kg version of the A22LS. Cabin a fantastic 129 cm wide and great visibility with fully see-through doors and a narrow panel. The foxbat is aluminium except for the control surfaces and under the wings. My Foxbat cruises at 80 kts but has big tyres could do with a finer prop setting. Aeroprakt A32 is fast and has a very low stall speed - amazing. I have not really considered the 450 kg planes because 600 kg is the limit here. Disclaimer:50 hr plt.
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