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Flyer40

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About Flyer40

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  1. It's a real shame to see it destroyed. Had some fun times in RWK. Happier days...... a trip to the beach.
  2. Of course that was a broad generalisation, but from my own experience, I had a V8 that averaged 10.5 overall but would turn in under 8 on the highway where it was at 1800 rpm and never needed to change gears when a hill was encountered. At the same time I had a 1.8l Corolla work car that spent a lot of its time at red-line rpm trying to keep up with freeway traffic and used a lot more than 8. That was almost ten years ago and car engine technology has advanced where aircraft engine technology has not, so the analogy wouldn't work with newer cars. Just to show how incomparable this can get, I now have a 4 cylinder car that uses more fuel than my older 6 cylinder, but it makes 90Kw more than the 6 cylinder.
  3. Andy, can you add more info about how operating at a lower rpm reduces the life of the Jab engine. It sounds counter intuitive, I'd like to know their reasoning. As for bigger engine efficiency, the article I mentioned earlier stated that the big engine uses 7.5 gallons an hour while the 360 in the same airframe uses 9 gallons an hour. I'm not an engineer but I'll have a go at why I think it works: Assume both engines have a volumetric efficiency of about 80%. In the Bearhawk the 540 cruises at 40% power, the 360 at 75%. The O540 will theoretically consume 432 ci of fuel/air gas per revolution at sea level at full throttle, which at cruising rpm of 1900 is 820,800 ci of gas per minute. The O360 will theoretically consume 288 ci of fuel/air gas per revolution at sea level at full throttle, which at cruising rpm of 2300 is 662,400 ci of gas per minute. At this stage of the calculation the 4 cylinder engine looks more economical. But I'm guessing the 360 would be at or near full throttle to maintain 2300 rpm with a constant speed prop. Whereas the 540 would be throttled back somewhat. And that's where the big engine gains its advantage. I don't know how to do the next part of the calculation but for the sake of illustration, 40% of the 540's maximum possible fuel/air gas consumption at 1900 rpm is 328,320 ci per minute. Taking 75% of the 360's max at 2300 rpm we consume 496,800 ci of gas per minute. So for the same cruise speed the big engine uses 168,480 ci less fuel/air gas per minute. There are obviously a lot of other variables which I deliberately left out because I'm illustrating a concept, not performing an engineering analysis. If I were to think of an analogy it would be the V8 engined car that uses less fuel on a long highway journey than a 4 cylinder car.
  4. Depends on your point of reference. To me the 182 is the safest and most comfortable way to travel with the family. Stable ride, luxurious seats, airbags for safety, more information than I can poke a stick at, and an amazing auto pilot. Certainly not truck-like. I'd be more inclined to compare it to a 5 series bee em. But I agree, certainly very different to a J230. Anyway
  5. A big engine can make good sense in terms of efficiency. I just read about a Bearhawk with an O540 in place of the more usual O360. This aircraft also has a modest Vne but the big engine gives incredible STOL capability and in cruise it's throttled way back to 19 squared (about 40%) where it turns the same cruise speed as the 360 but does it on much less fuel than the 4 cylinder. Wonder how much a 5100 powered J400 would consume at normal cruise speed?
  6. Craig, in my line of work I spend the majority of my time determining how and why people brought themselves to grief. Philosophically I believe there are two types of people; those who are ignorant or complacent about their risks, and those who are consciously aware of their risks. These two different mindsets fundamentally shape behaviour, decision making and therefore outcomes. I find it is the former group who are typically involved in accidents. Or put another way, people really do make their own luck. I think you'll be just fine.
  7. If anyone want's to start a petition I'll sign it and I reckon greater than 9 out of 10 pilots would sign it. Personally I would rate the ASIC debacle as the most discouraging thing that ever happened to aviation in this country.
  8. I heard the Jabiru rep at Cowra talking about the air ducts pulling plug leads off during his presentation. It's surprising they haven't been more proactive in providing a solution given they obviously know about it. What's the likelihood of fitting a Sonex aluminium baffle kit under the hood of a Jab? [ATTACH]6819.vB[/ATTACH]
  9. Thanks Brent. This is indeed brilliant, if it happens that way.
  10. No point me nominating, my grand total flight hours in RAAus aircraft is 0.3 hrs. But I can write a review based on my experience with the G1000 if you like, and I'd be happy to review other glass products. As Martin said, once you've used glass there's no going back. If I ever do build a Morgan Sierra it may be the first one with an all glass cockpit.
  11. Glad you asked this question Rocko, I've been try to get my head around this myself. Taking this question a little further, assuming that the 750 kg weight increase is approved and aircraft like the cessna 150 and some RV's come under RAAus administration, could the owner still do their own maintenance and approved modifications, even if they weren't the original builder in the case of the RV?
  12. I really enjoy reading pilot reports, but the subjectivity of the individual reporter has always been an issue for people wanting to put that information to practical use. A former fighter pilot is going to interpret flying qualities and say different things than someone who has always flown ultralights. It'll be a real accomplishment if you're successful in defining a test report bench mark, especially if the results are repeatable regardless of who the pilot is. Can I request the Morgan Sierra as one of the first tests? As far as I can tell it's one of the few aircraft in this country that's never had an independent review published. Actually a comparison between the Cheetah and Sierra would be a good idea.
  13. Another classic book of the same genre as Chickenhawk is 'The Ravens' by Christopher Robbins. It's about FAC pilots who flew in "America's secret war in Laos". Locally I'd recommend 'Aiming High' by Jon Johanson and 'The Luck of the Draw' by Ted Sly DFC, MID.
  14. Most of the PPL's I know actively avoid CTA, which is understandable given that it can seem a bit daunting until you get the hang of it. But it's a shame those guys are not making the most of such a valuable resource when it's available to them. I thoroughly enjoy flying in controlled airspace and encourage other pilots to discover how enjoyable it can be. Not only is it fun, it's a whole lot safer than flying OCTA and sometimes it can reduce the cost of flying by offering a more direct route.
  15. I'm going. It's not far from our place so I'll be driving down.
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