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Gentreau

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Everything posted by Gentreau

  1. However my understanding is that with jets the lift/drag profile is not the only consideration for economy. High altitude gives economy benefits which are presumably greater than the losses caused by flying the wings at a relatively high AoA. Those benefits must be substantial as even the shortest comercial jet flights climb to high altitude for the cruise.
  2. The phenomonem you're referring to Phil is the narow speed range at high altitude between aerodynamic stall speed and critical mach number. As altitude increases, given a constant True Airspeed (TAS), Indicated Airspeed (IAS) reduces. One interesting effect of this is that you can cruise at high altitude with a TAS in excess of VNE without damaging your aircraft, since VNE is given as IAS. As we all know, the critical angle of attack of a wing flying straight and level can be translated into a fixed stall speed givan as an IAS. Now, when you get silly high, like commercials and Learjets, the IAS at maximum cruise speed (TAS) starts to get quite close to the stall speed. Eventually you reach a height at which the smallest reduction of speed stalls the wing. Now there is another figure which is important and that is the critical mach number of the wing. Try to fly the wing beyond this speed and the air flowing over it starts to go supersonic in some areas and cause massive drag. Since the speed of sound reduces as air gets thinner (as we go higher) the equivalent mach number for the max cruise speed gets closer to the critical mach number. So, at high altitudes, you have a small speed range to play with. Go a bit slower and you get aerodynamic stall, go a bit faster and you exceed the CMN and stall again !
  3. Who let you in here Phil. They had instructions at the door to keep you out !
  4. Is that within the time limit specified by the constitiution ? When the members are so p****d off that they call an GM, does saving a few dollars matter that much ? If saving money IS so important, why not move the board meeting to an earlier date ? .
  5. Don't you think Gavin, that if the communication between the board and the membership had previously been considerabley more open and transparent, that people would not vent so much frustration when they do get a chance to speak to a board member ? Unfortunately the argument is self fulfulling. 1. Don't communicate. 2. Start to communicate a little. 3. Come under attack for not communicating. 4. Stop communicating all together. 5. Repeat ad infinitum.
  6. Gavin, thanks very much for responding so openly. I'm sure the vast majority posters on here understand that you are not personally responsible for everything that happens, and I would suggest that everyone remembers that when replying to the board members who have the guts and good manners to reply on this forum. That said I have to say that I find the logic of two of your posts to be somewhat inconsistent. As you will know from your experience of reading legal texts, the devil is in the detail. You say in one post that an email resignation is not valid unless sent to the right person, but you also say in another post that the board felt the necessity to vote on accepting the withdrawal of that resignation. So that raises the question, was the resignation valid or not ? If it was not, then the board had no reason to vote. The fact that the board voted indicates that they thought it was valid. So which was it ?
  7. Interesting, you are saying that a specific output around 100HP/ltr is not highly tuned in terms of modern technology. I guess with F1 engines producing around 350 HP/ltr that is probably a reasonable statement. Elsewhere there is a discussion going on about a Swiss made engine which has been converted for aviation, and that produces 102 HP/ltr at only 6000 rpm. Some people seem to consider that to be impossible. Does the maximum rpm have an effect on the specific output ?
  8. Hi Gavin, thanks for that information. Can you please confirm that: 1. All previous resignations submitted by email have been refused by the board as not constituting a valid resignation ? 2. All previous resignations have subsequently been made by a submission in writing before being accepted by the board ? If not, then there are double standards in play. Dura lex, sed lex.
  9. "As soon as you make something idiot proof, they invent a better idiot"
  10. Out of interest Andy, in what format are those additional documents required ? Paper or electronic ?
  11. Or you could just come over to France where the sun always shines
  12. Thanks planet47 and my apologies for the inaccurate personal pronouns, unfortunately your username didn't give me many clues. (Sorry, just noticed that gender is shown in the user profile, I'll check in future). Anyway,now you have explained the reason for your question, it is understandable, and I think that others have already answered it admirably.
  13. I'll bet Google knows, did you ask them ?
  14. Thanks very much for giving your perspective naremann. It certainly looks like a valuable service and you have my sincere respect for giving your time and aircraft to it. My questions were solely to understand the legal framework as I know that most CAA's are very uptight about PPL's recieving remuneration for anything. I can see however that since fuel costs represent a minority of the overall costs of operating an aircraft, paying them would not surpass the cost sharing limit, even if you only carry a single passenger.
  15. You'll have to get an IMC rating so you can go up and see it. :)
  16. No worries, you're not alone. Somebody else on here told me to phone my local RAAus rep if I had questions. I'm still waiting to find out who that rep is ........
  17. According to the website http://www.vikingaircraftengines.com/Technical/Tech.html "92 Octane minimum (10% Ethanol max)"
  18. Some might say that the recently resigned president is still legally an ex-president ..... .
  19. Not trying to second guess, but to understand. It looks like a valuable service that could be run elsewhere. What I wanted to know was if it relied on some Australia specific regulation or derrogation. Thanks for the clarification. .
  20. Ok, so basically the pilots are donating the fixed cost part and recieving compensation for fuel, which probably works out overall as a bit less than full cost sharing. Sounds like a valuable service too.
  21. Doesn't that by definition require the pilot to be a CPL ?
  22. What's the law in Australia regarding private pilots receiving financial compensation for flights ? .
  23. I only base my observations on the information given, and try to offer an independent opinion. I commented on what John said and others seem to agree that the system is not logical. Which rep do you suggest I call, is there one for my area ? .
  24. That was the idea. Not claiming it would necessarily work of course .
  25. I'm confused. If the vote closes as soon as you have a majority, how can anyone then change their vote ??
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