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shafto

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  1. Check this out! Pirate Party Wins and Enters The European Parliament | TorrentFreak There are clearly a lot of people that are Pro-Downloading, with a party now sitting in Parliament in Sweden. After founders of The Pirate Bay some how were charged the Party was formed. Its a step anyway.
  2. Thats what I ment by Martin J400 putting Straight 100 back into the engine, it wont help with fixing the oil consumption. And like you said cylinder bore's need de-glazing/honing or Straight 100 will do nothing.
  3. Hi Alan here Just a few things so bare with me. Your leak down tests you have done, they will give you no indication as to why your loosing oil. A leak down test will only test the compression, or the state of the top two rings, it will not test the state of the oil seal. The differing rings do completely different jobs inside the cylinder, so dont think a leak down check will show a worn oil ring. If compression leaks past the front two rings the oil ring will do nothing to stop the air heading into the crankcase. I personally dont know enough about the 3300's so I cant comment on weather 90mL is excesive. But If you are using excessive oil it will show up on your spark plugs, they will be oily and look glazed. If they are not, well I would lean towards a bad run in period. If the engine was babied at all with straight 100 oil, the rings will never seat and you will have a high oil consumption and not really any other symptoms. A note as well, if you are putting straight 100 back into the engine the cylinder bores HAVE to be de-glazed or all your going to do is ware away gears or other components. And that does mean pulling each pot off. Once a cylinder is glazed over, the rings have already seated and the cylinder wall is lined. All you will end up with is unnessisary ware on other components and gears. In relation to only filling oil to a certain mark becuase any higher it just "blows it straight out". The type of oil used is Ashless Dispersant in regular operations. There are two things behind the oil, obviously the 'ashless' part and 'dispersant' part. Ashless meaning that as the oil cleans the engine (key point here) it cannot leave behind any ash, embers or any other crap it may pick up while its lubricating and cleaning. Dispersant being that all the crap that the oil picks up while cleaning are deposited and "dispersed" throughout the oil some being picked up by the oil filter, while the rest stays suspended in the oil. If you wanted to get technical you could call it a aqueous. Now my opinion and held by alot of other people is that the cheapest and most effective way of ensuring engine longevity is good clean oil. So question is why not add the oil to the full mark? Keeping the oil tank full for each flight will only dilute the crap suspended in the oil and flush all that gunk out, but you wont even need to put a oil pan under it! The oil filter will be cleaner and the insides of your engine will be to. It is only a win win situation, less ware, cleaner engine. The piece of mind that there is a full tank of oil when oil pressure starts dropping might give you those extra 5 min of flight time to make a safe landing is also worth mentioning If cost is an issue just remind yourself the cheapest thing you can do to ensure good engine life is good clean oil! So why risk it? Keep it clean Alan *ps sorry about War and Peace there but better to try and give too much info than not enough
  4. Agreed with Maj Millard there, have a good look over the coax cables and check the terminations....Could be a braid thats frayed away from the connector. Another thing to check is where the coax cable actually is loomed and how it is loomed, if it has been loomed into a loop too tight the braid/insulation will degrade and you will get feedback. Usually caused from over zealous zip tieing also just have a look where the coax runs could be as simple as that.
  5. Why would EAA recommend this? That just is insanity! Like Thruster87 said it will just leave stress risers, and totally destroy the alclad! When you do use the Alodine, read the MSDS and stick to its saftey warnings. Alodine is not something you want in your eye let alone on your skin, so make sure your covered up
  6. The Japenese used to call them Wistling Death becuase of like stanzahero said, the air rushing the gun ports, I was recently at Temora for the flying day and let me tell you the sound is unmistakable, and the way it flew you can see why it excelled as a ground attack. The pilot flew it up to the top of a loop and rolled it over in a mock ground straffe, and the Wistling started and airspeed incresed got louder and deaper, it looks completely rock solid in a dive and a awesome gun platform!
  7. Went for a wonder around Caboolture airfield today, and stubled accross a open hanger with the Boomerang being restored sitting in it. Apparently its a week away from flight tests, engine has been run (by the looks of the leaking oil). Found out a little about it to, didnt realise it was being rebuilt as a two seater...Didnt even know there ever was a two seater, but apparently the airforce modified one airframe to a two seater. So this guy will be the 2nd two seat Boomerang ever. I have to say the build quailty is amazing, it looks like a new aircraft with clearly no expense spared. Chatted to the engineers about the second seat, appartently not alot of structual modification or strengthening was needed. But there obviously was not alot of documentation considering only one other has ever been built! Anyway Ill let the pictures speak for themselves!
  8. Its weird that there is no mention of it in any manuals or IPC's for that matter. Only thing i found was a note on the exhaust installation all it said was (Inlet pipes not welded in) :confused:
  9. Ah so its sort of like a crush gasket? Or atleast a interferance fit
  10. Hmmmm this is somewhat worrying "Gaskets and salastics are only a temp fix". oh and this "do not leave them too long leaking"..... Im not trying to have a dig at you Jablev2. Its just those comments are worrying..... I couldnt find anywhere where Jabiru said in a manual where welding/permanently fixing the exhaust was ok, but ill just assume so. Actually I wont even touch on that becuase i have no knowledge of what they have said. But what i do know is the exhaust baffle and dump pipes are very similar in design to what a Beech 76 Dutchess have installed on them. I personally have inspected and removed 5 exhaust sytems off different aircraft in one year, becuase of leaks. 3 of them were leaks in the baffle, so a easy fix if you weld the exhuast on. BUT the other two were cracked around the flange at the head of the engine. In the case of permanently fixing, I would hate to think of the removal and cleaning/machining of the head to have it fixed. Now what worrys me the most is the actually welding. The problem is your welding/attaching two different metals together. The biggest and i mean huge problem here is the metals expand and contract at completely different rates to each other. Over time you will either crack a cylinder pot or the exhuast. And that is one of the reasons for a gasket in this case. A gasket is one of the cheapest components you can replace on an engine. You really should have a spare set for a 100hrly, you may use them or you wont. But atleast you have them there. The maintanence manual on the 3300 states the system should be inspected every 100 hours. That includes the gasket. If the exhaust system is leaking the aircraft should never leave the ground. A single crack on the baffle calls for it to be pulled off and welded. For two main reasons; 1 it robs the engine of power and 2; the leak leaves NoX fumes to enter the cabin. Both could lead to 'incidents'. If anyone has had a engine have a crack in the exhaust they will know what i mean by power loss. The engine runs like a dog. The sealant to use is stuff called Loctite RTV (Red High Temp) you can get in from places like Aviall, Aviaquip etc....You buy it in small tubes or you may still be able to buy it in calking gun size which makes it cheap in the long run because it wont go off it you plug the end. You only need to put genuine squirt on the gasket and rub it in on both sides with your fingers. The excess will get squished out and burnt off. Also helps when re-installing keeps the gasket stuck in place :thumb_up: In summary gaskets will work fine if they are used with the right sealant. You cannot re-use a paper/thin gasket but that is just what happens. Have a set of gaskets handy and you will never have a problem. Simply if there is a leak, it should be fixed.
  11. No probs LEJ, it looked like there was a fair bit of confusion out there! Hopefully people will understand what the issue is, and it has nothing to do with composites failing. Or atleast thats the least of your problems!
  12. Hey all After reading through all three pages I've decided to make this my first post! Woo SO im not a flyer (yet:thumb_up:), but am a budding engineer. Now after reading though manuals, pilot and aircraft specific Ive come up with this, now of course the PIC decideds weather to fly or not regardless of what the manual says, so ill let you guys decide. After reading through the Pilot Manual of the J160, i obviously came across the section where is states the section where it says 38c is max OAT. After looking at the Takeoff Config Matrix i did some rough calculations to give estimates as to how the aircraft will perform. Unlike some earlier posts, the reason there is the temp range is because of aircraft performance, not the composites failing. OK so here are the assumptions the matrix is your in a take off config, with 68 KIAS. So easily you can see at 38c OAT and at SEA LEVEL climb rate at MTOW is 461ft/min. Extrapolating that out you can assume that you would loose around 120ft/min climb for every increase of 20 degress. So you could expect a climb rate of around 320-360 ft/min. I wouldnt like to think what the climb rate would be if you got even the slightest down draft. Also have a quick look at take of distance needed, I've put that table up as well, give yourself a rough idea how much more runway you will need to even get in the air. How about a quick look at how the engine performs so you can all see the power loss. I used The Bureau of Meteorology's annual national average of relative humidity, the east coast is 70% and west coast 60% to 70%...so I'll just say 70% relative humidty (RH) for arguments sake. Jabiru 2200 at 52 degrees at sea level with 70% RH; the relative HP is 85.7% of 80HP or 68.57 HP. Now thats at sea level. Its only going down as altitude increases as well. Jabiru 3300 at 52 degrees at sea level with 70% RH; the relative HP is 85.7% of 120HP or 102HP, again its only going to go down. You will not regain HP performance by going higher. Anyway there are the reason's why there is a max temp. Now personally I agree with the people that have said if you operate out of the Operating Handbook you are operating illegally. Imagine you did crash you didnt have climb rate, and hit a tree, you killed your best friend and you survived. The court case begins, the judge asks you under what bases you operated outside the book. Your only defense is Old mate Jabiru said you could fly it to 52 degrees. Guess what? old mate jabiru will convinenlty forget he said you could operate it at that temperature. All he has to say is you should have read the manual. The final nail in the coffin is the warning above the takeoff distance matrix, and i quote "Extrapolation outside the boundaries of the Take-Off Distance Table is not permitted. When the outside air temperature and/or pressure height is below the lowest range included in the table, the aircraft performance shall be assumed to be no better than that appropriate to this lowest Jabiru Aircraft range. The performance information is not valid when the outside air temperature and/or pressure height exceeds the maximum values for which this information is scheduled." (Jabiru J160-C Pilot Operating Manual Page 5-4 Rev 21 Dec 2005) Actually that quote is used on all performance tables. Take off performances, landing distances, everything So the answer is yeah sure you can fly in 52 degree heat; you could fly it at 70 degrees if it got that hot, you can even fly a plane without a licence too if you want. But as a consientious pilot you should know your climb rate is greatly reduced, and thats the least of your problems. As soon as you operate outside the manual, if anything goes wrong you are resposible for the lives you damage.
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