skeptic36 Posted February 15, 2012 Share Posted February 15, 2012 With Service books, some handy walkthroughs from the internet( found a great one for 912"s the other day and learnt a few things!!) ! HI Planechaser, Do you have a link for that? Regards Bill Link to comment Share on other sites More sharing options...
old man emu Posted February 16, 2012 Share Posted February 16, 2012 When you are deciding on a LAME or L2 to do work on your airplane, one thing you should examine is his/her experience on your airplane type, or similar types. Remember, a person can become a LAME by working on 747s for QANTAS, but still would not have the experience to do regular maintenance on a C152, or something powered by a Jabiru or Rotax. As for qualified rag and tube; wood, or composite people, they are a bit thin on the ground. And by qualified, I mean holding a CASA approval for that sort of work. OME Link to comment Share on other sites More sharing options...
facthunter Posted February 16, 2012 Share Posted February 16, 2012 Don't they have to have an approved workshop as well? Nev Link to comment Share on other sites More sharing options...
old man emu Posted February 16, 2012 Share Posted February 16, 2012 Don't they have to have an approved workshop as well? Nev Yeah. That's a good point. A person can be a LAME, but the premises where work is done has to be approved by CASA. Apart from being a suitable place to work (sealed floors, etc) there have to be available the appropriate tools, up-to-date data for the airplanes being serviced. We are not even supposed to go into an owner's hangar to do an oil change to save having to drag the airplane out and taxiing it to ours. OME Link to comment Share on other sites More sharing options...
Planechaser Posted February 16, 2012 Share Posted February 16, 2012 HI Planechaser,Do you have a link for that? Regards Bill Hi Bill, http://www.conairsports.co.uk/downloads/912%20maintenance%20article%20-%20inc%20carb%20bal.pdf I found this helpfull on a number of things. Oil trapped in the cooler and carb balancing explaned simply for a start. It's a PDF so you will need Acrobat. Cheers, Hamish Link to comment Share on other sites More sharing options...
Planechaser Posted February 16, 2012 Share Posted February 16, 2012 The Rotax 912 manuals specifically prohibit using any sort of airswitch hours as the basis for maintenance. Servicing has to be done based on engine run hours (start to stop)Cheers John That's just one engine manufacturer. Jabiru, Lycoming and Continental don't prohibit it.OME Can Jab and Lycoming really think there is any substitute for engine run hours?? I can't think of any engine maintenance I've had anything to do with, from small petrols to large diesels and all in between, that has been based on anything but actual engine hours. Hobbs meter, rattle clock, timer on the injector line, whatever. Even vehicle maintenance based on km's is only a rough guide. Motorbikes, the real workhorses, have hourmeters on them for best practice maintenance. When it comes to oil, start to stop is all that matters in my book! Link to comment Share on other sites More sharing options...
Planechaser Posted February 16, 2012 Share Posted February 16, 2012 That's right. I know it goes against the grain, but thems CASA's rules. As I said, that is the requirement of ONE manufacturer. If you use one of its engines, then you either keep separate logs of engine and flight hours, OR you run your airframe out of hours quicker than is allowed. I would suggest that you specify in the airplane's service procedures which record is to take precedence for servicing. OME Missed this bit. I run air time for the air frame, and engine hours for the donk. Sounds like a pain, but over the life of the engine it adds up. Do you run your air frame out a bit early, or run your oil a bit too long? I prefer nether. Link to comment Share on other sites More sharing options...
old man emu Posted February 16, 2012 Share Posted February 16, 2012 I must admit, it is easier just to work to engine time. A Hobbs meter really is only accurate around cruise RPM. Below 1500 RPM they run slow as compared to real time, so in a metered 100 hours, the engine probably doesn't actually operate for much more than 105 hours real time, which is really neither here not there. How many of us run up 100 hours in 12 months anyway? Separate recording of airframe hours is only really important for airplanes that have time limited airframe components. I don't think any RAA airplane comes into this class. If we look at magnetos and gearboxes, maintenance based on hours of operation is usually carried out within a few hours of the required time. It is legal to fly an airplane to a maintenance facility if, during the flight, the time in service will pass the 100 hour mark. This leeway is usually limited to about an hour. You couldn't fly home from Broome to the East Coast an go overtime during the flight. OME Link to comment Share on other sites More sharing options...
djpacro Posted February 16, 2012 Share Posted February 16, 2012 It is legal to fly an airplane to a maintenance facility if, during the flight, the time in service will pass the 100 hour mark. This leeway is usually limited to about an hour.. XOME I think you'll find that the 100 hrs, where it is applicable, is a hard limit. Link to comment Share on other sites More sharing options...
David Isaac Posted February 16, 2012 Share Posted February 16, 2012 ....... A Hobbs meter really is only accurate around cruise RPM. Below 1500 RPM they run slow as compared to real time, so in a metered 100 hours, the engine probably doesn't actually operate for much more than 105 hours real time, ...... OME aren't you confusing the Hobbs meter with the tacho hour run counter. The Hobbs is typically an oil clock activated by the engine oil pressure switch and the reading is simply a clock turned on by the oil switch. The tacho hour counter is the one that varies and is designed to record accurate hours at cruise RPM and below at lower RPMs ... kind of makes sense really, the engine is only working at loaded RPM. Link to comment Share on other sites More sharing options...
facthunter Posted February 16, 2012 Share Posted February 16, 2012 This is nothing new. Various ways of recording times to fatigue and service inspections/overhaul have existed for a long time. There is also shelf life and overhaul times bases on years of installation,( magneto's) If one has to equate engine idling with inflight engine loads, there is a great variance Engines are not doing much when you are taxying. If you are operating in dusty conditions or not using the engine regularly there would be more significance in that. Short sectors are usually more telling on engines, and an engine starting cycle can be more stressfull on some turboprops than at any other time. CASA approve certain methods (where they get involved) and the engine/prop/airframe log books would make it quite clear which method was in effect. A time switch that activates on oil pressure or ignition switch is certainly OK for the hiring organisation, but I can't see it as being really appropriate for any other measure and is hardly fair on the hirer if you get held up in a queue. At least the mechanical meter activated by the engine tacho measures the number of revolutions the engine does and when you are idling saves you some money. The common method for air time is an airswitch activated by a microswitch on an undercarriage leg. it's a bit odd that Rotax would explicitly ban the use of other than a "total time" concept. It's not a very sophisticated approach, but acts in their favour and your disadvantage. Nev 1 Link to comment Share on other sites More sharing options...
Guest davidh10 Posted February 17, 2012 Share Posted February 17, 2012 I think you'll find that the 100 hrs, where it is applicable, is a hard limit. Maybe this also varies between manufacturers.. Rotax allow up to +10%. Maybe that is because of the use of total run hours. ...it's a bit odd that Rotax would explicitly ban the use of other than a "total time" concept. It's not a very sophisticated approach, but acts in their favour and your disadvantage. Nev A good reason, however, to log air hours separately for airframe maintenance. Link to comment Share on other sites More sharing options...
djpacro Posted February 17, 2012 Share Posted February 17, 2012 I guessed that OME was referring to 100 hrly inspections per CASA regs and so was I. Sorry, my comment is obviously not applicable to this thread at all is it? Link to comment Share on other sites More sharing options...
Thirsty Posted February 17, 2012 Share Posted February 17, 2012 Separate recording of airframe hours is only really important for airplanes that have time limited airframe components. I don't think any RAA airplane comes into this class. The J160 and probably the other Jabs have a 5000 Hr requirement on the wing struts and the control cables every 10000 Hrs or something like that. I think Jab also allow a 5% tolerance on inspection intervals if using an airswitch as opposed to a hobbs meter. Link to comment Share on other sites More sharing options...
facthunter Posted February 17, 2012 Share Posted February 17, 2012 RAAus will end up with "lifed" components as time goes on as does all other aircraft. This could be part of the initial design as a conservative estimate, but would be based on design loads (calculated) and not from direct strain gauge readings , or fatigue tests, etc which are not required, for our type of plane. When inspections find cracks, deformation,corrosion etc that follow a consistent pattern, things like airworthines directives will be issued, requiring repair, replacement, modification etc or in an extreme case the type may be grounded. This is a logical process and the reason why every fault/repair should be reported and help keep the aircraft airworthy for all of us. Link to comment Share on other sites More sharing options...
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