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aro last won the day on October 17 2018

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  1. Serves me right for trying to reply to 2 messages in one post rather than double posting. Only #1 was referring to your message. The rest was in reply to Turboplanner. My argument is with the assertion from Turboplanner that: I doubt that that information is in BAK because it is often not true. (You would know better than I what is in the BAK, I am happy to be corrected.) The full flap balloon over an obstacle is often (wrongly I think) taught as a way to get extra obstacle clearance over the POH/AFM technique. Either way I don't think using full flaps for obstacle clearance is good information to give to a student studying for BAK.
  2. It was me who said that. I wasn't suggesting that you crashed, just that it wasn't a technique that should be taught in BAK. 70 feet is a big balloon. The technique was demonstrated to me when I did my PPL, from memory the typical balloon was 10-20 feet. It was supposedly a way to clear fences, not trees. You can't create energy from nowhere. The energy for a balloon comes from airspeed. Flaps may be useful if your airspeed is low enough that trading it for altitude puts you at risk of stalling. However in that case you only have energy available equivalent to the difference between stall speed with and without flaps, which isn't 70 feet worth in our aircraft. If you started at 100 knots and had 70 feet worth of balloon energy, the elevator should have been sufficient. If the flaps cause extra drag, you will end up with more energy at the top without them. However flaps might change the trim enough that the aircraft pitches up with less elevator input, giving the impression that the flaps produced the climb. Consider the situation in this thread: For maximum performance (recommended for high density altitude), he needed flaps 0 and 59 knots. Instead they had flaps 10 (flaps 10 recommended climb is 56 knots) and 65-70 knots and at the high density altitude they weren't climbing. Do you think dropping full flaps would have helped them over an obstacle? It might have given them 10 feet if they timed it right, but then they would have been sinking rapidly. As I said in that thread, know the configuration that gives best performance and the speed you have to fly to achieve it. You can put that in the BAK.
  3. Every time I line up on the runway I rely on the theory of flight, I haven't been disappointed yet. If you feel you have discovered situations where the theory doesn't hold, people would be interested. Just pulling back at 100 knots and trading altitude for airspeed should give you about 200 feet by the time you're down to e.g. 70 knots. You can try this at altitude if you don't believe the theory. Setup for 100 knots straight and level, pull back into a climb without touching the power - by the time you are down to 70 knots you should have gained 200 feet.
  4. Full flap would be unusual though? There is folklore that I have heard a number of times that the best way to clear an obstacle is to put in full flap as you fly towards it. Sure, the aircraft is initially likely to balloon. But what happens then? Maybe you climb away - depending on the airspeed and the aircraft, maybe even at a greater angle. But depending on the airspeed (e.g. too high) you could even sink again. So you really need to time the flap input. When it works, people are around to tell us. When it doesn't, maybe not... I hope this is technique is NOT actually being taught as part of BAK.
  5. Sure, but I suspect that you would have made it over without flaps as well. It was the "slowest forward speed and maximum climb was full power and full flaps" bit I was querying. Particularly in a BAK thread. It's not generally true, and shouldn't be taught in BAK.
  6. Pretty unlikely. Flaps add heaps of drag, to give a better angle of climb they would have to allow you to slow down more than they impacted your rate of climb e.g. 10% less climb but 20% reduction in stall speed would give you a better angle of climb. But it seems unlikely that flaps could reduce the stall speed enough without adding too much drag. The POH will have the answer, does it require flaps for best angle of climb? (Which is different to an obstacle clearance takeoff.) Flaps will certainly allow you to get off the ground sooner, if you are already flying they will not help you climb.
  7. The solution seems simple, Avdata send the information to RAA who pass on the bill to the owners. Then RAA require outstanding landing charges to be paid before renewing aircraft registration. RAA could add a fee to cover costs - or Avdata might even discount their fee to account for sending one invoice a month instead of one for every aircraft.
  8. Studies have shown that 9 out of 10 spreadsheets contain errors. If Avdata can correct errors in their bills, it is evidence that they are not heavily computerized. If you have ever tried to correct a billing error by the large telcos or utility companies it can be very difficult because the person on the phone can't change the computerized record. Sometimes I suspect there are policies of making errors that are small enough that the customer won't bother to go through the hassle of correcting them. A few dollars over a million customers adds up...
  9. I agree about the weather, it looks like the rain caused a down draft which translated into a strong wind blowing away from the rain, the same direction they took off. This is probably a common danger if you're taking off to beat weather. I gave them the benefit of the doubt on the mixture, they said "mixture set" rather than rich, and it didn't look fully rich. The flap setting is a very important point. I looked up a C172M POH online and definitely flaps 0 would be appropriate, particularly at high altitude. I disagree about the speed though. Waiting for 65 knots to rotate or climbing at 65 knots would degrade performance. For a maximum performance takeoff the POH specifies Flaps 0 Climb speed 68 mph (59 knots) until obstacles are cleared. For a flaps 10 takeoff, 65 mph (56 knots) until obstacles are cleared. Flaps 10 gives you a lot of extra drag. Too fast as well gives you extra drag squared. (Obviously that is slow and could be a problem in gusty conditions like this. Gusty winds and a requirement for a maximum performance takeoff might be a good reason to stay on the ground.) Often during training a few extra knots are added for "safety" and comfort. That doesn't usually matter because we usually have performance to spare. However, it can be deadly if you really need that performance. If there is any doubt about takeoff performance, know what configuration gives you the best performance, and know what speeds to fly to get it. However, whatever the reasons for the problem, the abort decision was good. Problems can happen to anyone, and it would be easy to sit there in denial and wait for the aircraft to climb until it is too late. Takeoff accidents are statistically much more deadly than landing accidents.
  10. In fact it clearly fits the classification of a private operation that can be conducted with a PPL: CAR 2 (7)(d)(v) the carriage of persons or the carriage of goods without a charge for the carriage being made. However, to me it appears that perhaps it should require an AOC: CAR 206 (1)(a)(vii) ambulance functions (or a purpose that is substantially similar). The issue seems to be that that gives Angel Flight more responsibility than they want to take on. They would rather that all responsibility rested on the pilot.
  11. CAO 95.55 has the answer. The requirements for an active restricted area are the same as for other types of controlled airspace.
  12. I don't have absolute faith in CASA - quite the opposite. I am saying that CASA do not always act according to the regulations, but if CASA say you must do X then (in practice) you must do X even if the regulations say something different - unless you want to take them on in court, which as you point out might not be a good idea. I am saying that (CASA permitting) we should be operating according to the regulations as written, not as interpreted according to unwritten principles behind them handed down through folklore.
  13. I do carefully read what you write. The problem is that if you and I have different beliefs about the principle behind a regulation, how is that resolved? The principles behind each clause are not documented - we only have the regulations to work with. Commercial operators have problems in large part because they engage lawyers who come up with an interpretation to match what the operator wants (and mostly they want to reduce costs and avoid complying with inconvenient regulations). CASA also appear to frequently disregard the text of the regulations and instead work off an individual's opinion of what should or should not be allowed. As I have said before, in the end the only thing that matters is CASA's opinion, unless you are prepared to fight in court. However what we don't need is to make up additional rules, like RAA registered aircraft can only be used for Recreational Purposes.
  14. Most of the confusion comes from people looking for "the principle" or "the intent" and then trying to find a way to interpret the rules to fit their own preconceptions. (Incidentally, that is often how lawyers operate. The client wants to do X, so the lawyer comes up with a creative interpretation that would make it legal. Then perhaps you go to court and the court rules on the lawyer's interpretation. Life tends to be simpler if you follow the regulations as written.) Care to guess what information the VFRG includes regarding "Classification of operations"?
  15. Where did you find the information about the "intent" of the legislation? My experience is that different people infer different intents depending on what they would like it to mean. It is better to read what the legislation actually says.