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Aircraft
Vans RV-12
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Perth
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Australia
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rgmwa's Achievements
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rgmwa started following Arnold rule; Mike Arnold's aerodynamic ideas , Buying a Hangar.. , Smashed on my airstrip! and 2 others
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You may want to consider White Gum Airpark east of York. YWGM Airpark - YWGM WWW.YWGM.COM.AU AIrcraft Hangar & Accommodation Units
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I thought he'd found Barnaby.
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The option for adding more fuel exists. As I read it, all they are saying is keep everything within the weight (and balance) limits.
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I think they mean make sure the total weight doesn't exceed 600 kg MTOW (for LSA), but obviously also keep the C of G within the acceptable range. They could have worded it better.
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The square bottle on my 912 just has a small hole in the cap with moulded filler marks as Skippy said. Why do you need an overflow tube?
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Sounds like a bargain. What would you have bought?
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Arnold rule; Mike Arnold's aerodynamic ideas
rgmwa replied to Max Volume's topic in Aircraft Building and Design Discussion
Found this: 185 kts using a 65hp Rotax 582 is pretty good. -
Class 5 medical declaration. My experience
rgmwa replied to NT5224's topic in AUS/NZ General Discussion
That definitely helps! -
Just out of interest, these are the various wind speed regions for Australia: If you're in coastal Northern Qld, you'll be in Region C (cyclonic). The number after the letters (eg A0-A5) denotes different wind speeds coming from different directions for each region, and can be used to fine tune a design. The typical basic design wind speeds in each region are: A 45m/sec (162 km/hr) B 57m/sec (205 km/hr) C 66m/sec (238 km/hr) D 80m/sec (288 km/hr)
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Maybe, but then they would more likely have said travel speed, not wind speed. Here's the reference: Abstract An extensive census and sampling program conducted in semiarid north-west New South Wales, Australia, has provided quantitative information on willy-willy (dust devils) characteristics and their environmental range. The observation of 557 willy-willies, made over a 20 day census period in summer, indicates that willy-willy frequency varies according to local meteorological conditions. An air temperature lapse rate, measured between 12 and 252 cm of the surface, of 0.9 °C m−1 was required for the initiation of the willy-willies, with their frequency increasing with lapse rate away from the surface. Willy-willies were also found to be restricted to wind speeds between 1.5 and 7.5 m s−1. Analysis of the spatial distribution of willy-willy initiation sites with respect to vegetation cover in the 35 km2 study area showed that willy–willy frequency increases with decreasing surface cover. The increased frequency of willy-willies with decreasing vegetation, could, over time, make willy-willies a potent mechanism in the evolution of the Australian landscape.
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Correct. That's why engineering firms carry Professional Indemnity Insurance. A study of willy-willies in NSW (557 willy willies sampled over 20 days) found they had wind speeds between 1.5m/sec and 7.5m/sec or (5km/hr to 27 km/hr). Seems a bit low to me, but that's what they said.
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No they can't, unless you bought a kit designed for Victoria or Tasmania and decided to put in on your block in Port Hedland.
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They do have some tension rod diagonal bracing in the roof and may also have it in the end bay side walls. They have also braced the unsupported rafter and column flanges back to the purlins and girts to resist buckling. I don't like the look of the portal connections much, but they may be OK. Other cold-formed structures I've seen used back to back C-sections bolted together with central gusset plates and spacers, and used bolts instead of Tek screws, but there are many ways to skin a cat. Cold formed structure design is pretty specialised and the design calculations can become very complex because the components are so thin and secondary effects such as small eccentricities in the structure become very important. It's pretty tedious and long-winded to do it by hand and you really need computer software written by experts, but then of course, it can be a case of garbage in, garbage out.
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Yes, it does have a gap and that helps to relieve some of the pressure. Basically, if the area of the opening/s allowing the wind in is greater than the sum of the areas of all the openings letting the wind out, the pressure will build up. If it's the other way around, you get a net suction effect. The effect of openings in the roof and walls in a building is taken into account in the design, for whichever direction the wind is blowing.
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I'm not aware of any failing. Our firm has been involved in a few and it's definitely something we consider and make sure there's enough weight in them, or some other form of anchorage to make sure the containers stay where they are, even if the fabric potentially gives way first. As I suggested before, lots of poorly built or under-strength structures never fail because they never experience their full design loads. The basic design wind speed for a normal building in Cue, for example, is 162 km/hr. Various factors based on the building's shape, the surrounding terrain, the part of the building being designed etc are then applied to convert that wind speed to a design wind pressure. In a cyclonic area such as Karratha, the pressure of the wind on a steel framed building can be roughly equivalent to the weight (acting upwards on the roof) of about 200mm of concrete and the same on the walls trying pushing the building over.