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Vecchio Austriaco

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  1. There is a 6mm set for sale if somebody is interested....
  2. I suppose the reason is that for speeds below the speed of sound the drop shape (cut trough a wing profile - it will be some kind of drop shape) is the shape with the lowest drag. If you go supersonic this changes. Then the shape with the lowest drag is pointy and not round. (look at the noses of supersonic planes...) Well the chance of going supersonic with a model are hopefully zero. Bad enough to hit the ground at "normal" speeds....
  3. Posted by Erfolg on 27/07/2020 12:17:15: This is not a new model in the strictest definition of new. In that the model was completed in Novemberish, the weather then intervened in delaying the first flight, immediately followed by the Corona Virus and subsequent restrictions. The first flight took place approx two weeks back. It was most fortuitous that that the grass on the field had been cut, albeit with the cut grass left to be dispersed by the sun to dry it and the wind to finish its removal. My test pilot checked out the model for control surface movements. The model placed in the centre of the field, throttle opened, the model raced across the surface with all the urgency of a racing slug, on Valium. Finally it was eased into the air, swinging left, which was arrested by the pilot. Slowly the model gained height, where a number of checks were made. Firstly response to ailerons, rudder and elevator, secondly stall characteristics. The test pilot then called for a landing, as the power was only just adequate to stay in the air. We then had a discussion, where it was decided that the model was vastly underpowered, secondly that the CG was probably a little to far forward. I decided that the initial change would be to re-battery from 3s to 4s. I would then move the CG to the mid position (by removing the nose weight) If the power was still inadequate I would re-motor. A check of the motor on 3s was showing a little over 200w pulled, on a 4s this went up to 360w (approx 1/3rd improvement). The next good day had us back at the field, a bit blowy. On attempting to arm the model, I discovered I had left the conversion plug at home. At present I am going through my collection of models and converting them from Deans to XT60 plugs, which mainly involves the ESC, in this case the ESC was done, this old, seldom used Lipo was still on Deans. This week-end was yet another good day. Back at the field the model was once more prepared and checked. This time the model raced across the field like racing Pony, on its 360w. My pilot did say, you know with a horse up front or 760w it would be a real monster. Who remembers those lectures with respect to James Watt his horse and deciding that a horse power would be 33,000 ft lb per minute? The good news is now the model takes of with authority, no tendency to swing left being on the stall. The roll rate is adequate, inverted flight good, loops good, spins reluctantly entered in both directions, stall turns fine. So + 6 months down the line the model is OK. Just about ready for me. Edited By Erfolg on 27/07/2020 12:20:17 Carl, what is that? looks a little bit like the Webbit (which I destroyed a few years ago) If so than it has a wingspan of approx 110cm. Mine was totally overpowered, could fly vertical. BR Vecchio
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