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Tex

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Everything posted by Tex

  1. Hi Doug, Basically the helicopter, often caused by blades out of position, gets out of balance while in contact with the ground and develops an increasing 'resonance' which exacerbates and multiplies on itself. Essentially an ever increasing vibration, but through the WHOLE helicopter, driven by an engine no less, but it needs something solid to 'bounce off' to cause the increase in frequency and amplitude... the ground! Hence the need to get airborne and let gravity and physics balance things out again. All helicopters are prone to it but some more susceptible than others because of they way they are constructed. 3 bladed helicopters are more likely to experience it than two..... hmmm....actually two bladed helis may be close to immune to it, not sure on that... and those with particular types of damping systems on the skids, which can both assist and contribute to the problem. I understand Squirrels have had some issues with it... Therefore always touch down as gently as possible and be very controlled with collective, even once both skids are on the ground (all helicopters land one skid first) be prepared to get it airborne again...
  2. Ground Resonance - only remedy is to lift off...
  3. Not just the RAA way... in AVIATION the way to build your hours, to get a non-instructing role is to instruct. I still find it quite bizarre. Any other 'industries" out there where those that have the least experience are encouraged to instruct to gain experience?
  4. WOW what a freak, he must know that route so well, what was his name? EDIT: Never mind, found it... Dan Osman
  5. Yeh the CBi is the go if it can be got. Later model and more expensive as a result... Pro's and cons are pretty broad H300 v R22 faster cruise in the 22 with the 300 dragging along at only about 70kts or 75 with nose pointed at the ground too. You also have no throttle governor in the 300 so all throttle work is manual, a bit more to think about but not a problem once you get a handle on it and very good skills to have IMO. The 3 blade semi articulated head is a better concept and design than 2 blade rigid, especially in rowdy air and gives a very stable and smooth ride cf the 'twitchier more sprightly feel in the 22. Can squeeze in 3 POB in the 300 (at least you can in the CBi). I reckon the 300 is a better more robust build all in all. Perhaps a little easier to fly well also, but slow... Lots use it as a training platform. I think a new CBi comes in a little more expensive than a 22... Probably a good reason for the lack of love in Ag work... But I think they have better TBO and component times so costs can even out, but that means little if you just want to burn fuel in 22 and turn them over. I understand you can pick up older model 300's pretty cheap at times If you don't need to whiz around at the speed a 22 can provide, nothing wrong with a 300.
  6. The guy who flies through the feature at the end managed to bounce off terra firma and deploy his chute just a few weeks ago in South Africa, hurt bad but survived. http://www.telegraph.co.uk/news/worldnews/africaandindianocean/southafrica/9018176/Base-jumper-survives-after-he-crashes-into-face-of-Table-Mountain.html
  7. I saw a myth busters episode where they did it on a car, the increased fuel economy was the gauge... I wasn't really fussed on the way they measured that, but it did show a significant improvement... a reasonable proof of concept experiment I thought.
  8. Could be good too... Golf ball effect?
  9. If you are paying it off fast then home loan is the best option IMHO. If you are not living beyond your means, you lack imagination!
  10. I saw one where they were barefoot behind a Dragonfly (in the US) they had the ski rope on the plane already and the skier on a jet ski... match speed, grab rope, then bail from jet ski.
  11. Hi Bruce, TP, Amperage stress is something LiPo doesn't mind, until you get low on voltage!! Each cell has a small voltage range 3-4.3v with in which they will not suffer damage. The C rating is the useful time of delivery. If this battery delivers at 30C, that is delivering all its useful current capacity until discharge @ 30 x 8.4 Amps (16 with the two of them) 1C = 1 to 1: so one hour. 30C is 2 minutes. The small lead is for balance charging... as the cells are all linked in parallel and series, just driving current into the output to charge is not the best way to do it because the cells do not receive a clean flow to suit each requirement (higher or lower charge) Balance charging ensures the each cell is topped up in a balanced way compared to the others. Balance charging is not always required but it is definitely needed with regularity.... always if possible. I do not know how the Anti Gravity mob have gotten around this but suspect, it is in the box. I have the 12cell on my 582 but think I need to go up one size. Yes LiPo are dangerous, but if managed properly they are like the fuel in your tanks. Damage to the pack is bad. Those ones... if they are going bad with out a damaged case will get puffy first. You know they are done if they do that and need to be safely discharged and disposed of.
  12. Yep, all the way to the ground...
  13. Anti-gravity batteries http://antigravitybatteries.com/ use them. Not as cheap as yours though you want very good quality batteries. They do not like being discharged and will be damaged if they go to low. Yes you will have 16amp with a discharge (charge) capacity x 30... but it delivers lots of its charge at that capacity (very efficiently) and once voltage drops it will drain the battery very fast. Ideally you don't want it to do much work at high discharge though to get best result and life.
  14. No, not made at the Moyes factory (well some bits are) Ozzie, I think all the tooling and jigs etc is over near Bill's at Bronte or nearby. Definitely no change from 55 I believe.
  15. Pictures by Jamie Sheldon
  16. Hi Bill, Plenty of fans in the Hang Gliding world. They have mainly been used as a tractor, as in towing, not configuration... the whole certification was a bit of an issue for a while as well I understand. They don't build to many of them and production is mainly supply for those wanting a tug. Otherwise supply was not that high. Also Bill (Moyes) is usually pretty busy and often would get Bobby (Bailey) over from the US to help with building them, but as utility aircraft... that was the real push for production. I only know of 1 in Australia that is exclusively used just for recreation and not towing, it is a 912. There are not many 912 specimens around in Australia but a few in the US... they are of course very very slow (as slow as they could be designed really): VNE 57kts, cruising at 40kts, Stall @ 14-17kts. So you don't go anywhere quickly. Would be an awesome airbike for a property owner!! Obviously they love flying in the heat of the day when it gets rowdy and also thermal a treat (glide not so good). But they are not what you would consider cheap. Here is the website http://www.liteflite.com.au/
  17. Nice!
  18. Tex

    Oil for 503 drifter?

    I might change for the same reason
  19. Tex

    Oil for 503 drifter?

    OK... I have to say it.... HUH? What locations are you in and what are the correct names of the oil ... So far we have Castrol 2T, Castrol 2T self mix, Castrol 2TS, and the Castrol Active 2T. As I understand it different countries have different names: In Australia there is the mineral based Castrol Activ 2T (Dark Red), In UK they call it ActEvo 2T, In USA they seem to call this just 2T. So 2T, ActEvo 2T are Activ 2T are, I believe, the same...??? Castrols Mineral based 2 stroke offering (there are still other Castrol products that have similar names that are synthetic mineral combos). The Castrol 2T self mix appears to be a legacy product in Australia? Pitched at lawnmowers and garden tools rather than liquid cooled engines. Then the new 'Power" range which here in Australia is the synthetic 'Castrol Power 1TTS' (blue) and seems to be called 'Castrol Power 1 Racing' in the UK and 'Castrol Power RS TTS' in the US. Castrol Activ 2T wins the straw poll
  20. Tex

    Drifter Pics

    One thing I don't see is the pump mounted horizontally, which is the Rotax recommended method.
  21. Tex

    Drifter Pics

    Yes thanks David I know it is 500mm from pulse port as max.
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