jetboy

As Dieselten points out, another dead end http://world.honda.com/news/2003/c030304.html I think he's a bit harsh on Wankel Rotary's though, there have been at least 2 manufacturers that have flown certified ones - Curtis-Wright ? and Diamond/Midwest , as well as a few perenials that turn up at Oshkosh - but as you still cant buy one yet, they dont count Ralph

Flyer I wouldnt be too hasty about electronic control, it just cuts reliability. The UL260 is limited to 20 mins or so with alternator failure and another good example is the Diamond DA-40 that crashed with double engine failure due to a bump in the power supply when they selected gear up - the ECU's momentarily stopped working. Theres very little in fuel efficiency because aircraft engines only need to operate around a 10% rev range most of the time and a carb or mechanical fuel injection and fixed timing is just as good. Just select the hp / weight / price combination you require and fit a solenoid to that starting enrichment control ( I must relable mine, "choke" is not what it is) that will turn a 3300 into FADEC control. Ralph

Yes thats the plugs I mean - havent seen any available for years and I didnt think they would be available in 12mm Ralph

Dont know if this is the best thread to ask but is anything known about the 14 valve failures being reported on the UK site? In reply to: Enrico 's message, "AAIB and exhaust valve failures" on 17:12:29 10/21/07 Sun Enrico – I’m the start of the AAIB investigation. On the 12th September I had a wonderfully day flying from Rochester to Manchester, on into the Lakes and then headed back for Rochester. With 45 min left to Rochester and at 1500ft I got sudden serious vibration. I reduced power and started to look for a good field, as I did so the engine stopped. Not my best ever landing (no smart comments please) but only minor damage to the aeroplane and no damage to me. In response to your questions Has anyone experienced this failure?- Yes, oh yes What is thought to be the cause? – One of my exhaust valves broke and was then rammed back out the inlet. The AAIB are still investigating and so far have taken valves from my engine, from a thruster, from a J400 3300 engine and several other new and used valves for examination. What can, if anything, be done to prevent this failure? – Nothing to do, my engine is hydraulic tappets and therefore no adjustments. Practice forced landings and maybe avoid long water crossing until we know what caused the failure. I have been flying behind two other Jab2200 engines after mine failed including this weekend and if anyone out there wants to offer loans then don’t by shy. I have 130 hours on type with only one crash landing so far. By the way the 3300 and 2200 share the same valves. In reply to: Eamonn 's message, "Re: AAIB and exhaust valve failures" on 08:57:45 10/24/07 Wed Congrats Eamon on a good dead stick ,you walked away from it ,a learning curve for all of us , today I had a conversation with a director of the BMMA and an inspector of same ,he told me information he had was their had been 7 failures of the Ex valve nature todate , 4 UK ,2 Aus ,1NZ , you have 100 plus hours on engine ,but how old from new , and would it be possible to ascertain what fuel you were using ,the old chestnut has come to the surface regarding the use of MOGAS . In reply to: Howard 's message, "Re: AAIB and exhaust valve failures" on 1024 10/24/07 Wed In France there have 7 problems with broken exhaust valves. All these problems have been with the hydraulic tappet motors. We are currently investigating solutions using increased lubrication in the cylinder heads and have installed valve guide seals. We think that the guides have been wearing rapidly. We have found that this is particularly so on the front cylinders with the tail dragger aircraft Ralph

These gauges are not that simple for the purposes we are trying to use them. The last few issues of the Jabiru tuning SBs are quite clear that the primary instrument to confirm carb jetting is the lambda meter These are not cheap especially the required "wideband" type capable of showing absolute air / fuel ratio. They are also not suitable for leaded fuels so you cannot leave one installed. Proper EGT probes for 2200 / 3300 are listed around $100 ea. and the gauge I use is an amplified TSO'd one so as to give meaningful readings and be capable of running via a selector switch without resistance errors. I used four CHT thermocouples and have left them in place but normally only monitor #4 usually 20-30 F hottest. I only use the 1 EGT probe in the tailpipe because its too large to properly fit the headers, I use it as a relative guide and confirm that nothing has changed from original calibration. I treat it like the recommended CHT installation: once the worst cylinder has been determined by audit or other means (wish we could still buy "colourtune" sparkplugs) it is sufficient permanently monitor with the 1 probe. Of course if something occurs such as an intake leak that condition might not be monitored, I have had this occur on an 0-200 and got plenty of clues from a rough idle and whiter plugs but nothing shown on any gauges, mag drop or cruise etc. There is a case for wiring the engine up like a cardiac ward but where will this end - there is only so much you can do for a simple system before it becomes something else, its actually more reliable to ensure the jetting is suitably rich to allow for mixture scatter between cylinders, which JSB-18 seems to acomplish. Ralph - 210 hrs and counting

Damn right Albert and we have probably got more sheep over here than anybody else perhaps thats why when the transponder system was mandated in NZ there was a similar sort of free con going on so that GA operators could be encouraged to participate in this new airliner friendly gadget. The cost was around $3,000 per install and you could have the privilege of paying $300 per year for ten years if you afforded yourself of those very generous terms. Once the initial offer was closed you have to buy and maintain their piece of gear for them yourself. Not to mention they put the knife in a bit further by upgrading the radars last year so that existing TSO'd transponders did not work and had to be refurbished, then delivered the final twist by forcing everyone without one down to 1500' around provincial non ATC airports that dont have SSR radar coverage. I hope you can keep ADSB out of required equipment certainly below 5,000' & class G because there will be no free lunch - and the users wont pay. Ralph

I have made a CO meter using the sensor module from Farnell, a digital voltmeter module and a bridge circuit to set the zero and calibration. CO alarms are now available for less than what the parts would cost me at our local aero supplies however being designed for homes they do seem cumbersome and ugly in the cockpit. Another thing to watch is sensor life usually about 3 yrs. For aircraft I use the 18 month type spots I have had one go dark once in the rear of a C150A and that is why I built the meter so I could find the source - the meter is much quicker response and The CO was getting in the rudder cable slots and coming thru the rear cabin headliner. Ralph

ADS-B woulnt be as expensive if the VDL (VHF Data Link) option was mandaded instead of or in combination with the transponder mode S system. In the US and europe they use a different set of equipment for GA than what the airliners use. As ADS-B replaces the radars there is no need to ever install transponders of that type anymore in aircraft. Then a typical GA / ultralight / glider installation could consist of a robust GPS & ADS-B out processor connected to the VHF com. There are two (possibly 3) radios made in Aussie that would be able to do this with software change. And one of them already makes the suitable GPS. I would like them to do this because it would be easy to use in ultralights for APRS in a similar way to FLARM. Most ulralights already have the GPS and radio, the APRS box costs about $50 in send only mode. Ralph

Solar T62 is the most popular APU conversion and there are a few microlight helicopters - the Helicycle - that use them in NZ. I'm a bit disturbed about the assumption about ultralights not having them - ANO 95.55 on this site talks about must have a propellor and single engine - is that not OK in AUS? Dieselten is right on about the efficiency and fuel requirements, most APUs draw over 1 lbs / hp /hr fuel which is 60 litres /hr for the Garrett JFS100A and that only drops to about 45 L/hr for cruise there is an article on the web about a Kr2 in aus. that had one (3 actually if you count the rebuilds) If you just want to just feel the noise have a look at my testbed Cheers all

Leakdown test results on my 2200 @ 200 hrs. This has run with the lean&mean economy jetting for the last 150 hrs, 14 L/hr 80 / 64 80 / 71 80 / 63 80 / 64 air was only heard escaping from oil filler. Its probably better to put up with a little blowby than pulling the cyls for a hone and ring job with another 50 hrs run-in and no guarantee it will be any different. Been there done that with an 0-200. Engine was warmed prior by the time I finished checks the prop would stay put at TDC like its allways hard to turn when warm. (but I stay clear of it anyway) I rejetted per the latest revision Cruise EGT now too low, using 17 L/hr put back original needle jet .276, looks like 15 L/hr EGT WOT 640, max in cruise 679 @ 2850 rpm It appears the original economy tuning kit has not ruined the valves (yet), so I'm off to buy a more suitable prop and start rechecking mixtures again! Ralph

The small plate if bolted/riveted to the metal frame should be sufficient. can really only be checked with a reflectometer (swr) and from then on its a whole black art of adjusting cable lengths etc. so only worry about this if you have transmission troubles. Ralph

Its not really a "new engine from europe" just a development of an existing design that the wannabe Masquito helicopter builders in belgium found was unsuitable for their needs. http://home.comcast.net/~aeroengine/Masquito.html That company reformed in 2006 as ULpower to make the version you see now. I hope they got all the problem areas sorted, could be a very nice engine - there was one sitting in a hangar next to me dont think its been christened yet and theres one in hamilton which is rumoured to be going onto a Bantam. (some of which already use the 3300 in certain coutries) Ralph

Attached map of the first HF test with APRS running on a trip from Wayby to Parakai airfield. VHF tests were not so good due to lack of relay sites in the current network. Ralph

Sean, The Delcom mic input is like most handhelds of the era, Icom A2 etc. expect to 'see' an electret microphone capsule connected there and the ptt goes live when the mic is present. If you are using GA headsets they have an inbuilt amplifier that 'looks' like a carbon mic in terms of power requirement and audio level. A simple way to connect these is by running 12v power via 1 Kohm resistor to the GA mic socket, and 0.1 uF capacitor from there to the Delcom mic input. From there connect 4.7 Kohm resistor to aircraft ptt line, other side of ptt goes to ground. If the modulation level is too high, connecting a resistor in line with the capacitor, value between 4.7 Kohm and 47 Kohm should help. its likely the existing wiring does this. If you have an intercom, it will probably have better provision for the radio. Ralph

why i fly the bantam with the hand grenade motor Can relate to the discussion and scenarios here, it happened to me with my first Bantam 3 hrs experience with it from purchasing in a used and disused state. I wrote this in the same form as "why I fly the HS Stork" seen elsewhere, to illustrate that things dont allways happen in the order you have trained for, low inertia craft dont glide nearly as good as the Cessnas I did the training in, and a couple of hundred feet is shaved off before you know what the problem is. Where the training proved useful is the automatic reaction to let the plane glide. I have since then also trialed full prop stopped landings and dont make an unecessary habbit of them because it does increase the risk of a serious outcome and none of the planes I've done that in behaved much differently than say 3 knots headwind / tailwind on the day would make. For my current strip I am departing over water and mudflats so do a turn and climb along the shoreline till farmland is reached. any EFATO is going to be a ditching so keeping close to the circuit is the best option. Ralph Went across to bigger aifield than chookrun base need to practice forced landings real microlight pilots call them engineouts where theres better prospect of setting up glides plenty of room for variation I mean stuffups do circuits for a while so as not to bother the helicopter wait for him to clear off then climb out for 1500 feet overhead well make that 936 feet engine shaking ease back on throttle these 2 strokes sometimes do this no less throttle more shaking so full bore now motor wants to climb off the mounts back to idle now I can see the prop it doesnt usually do that now its 700 feet runway should be behind me need 270 turn need 55 maybe 60 mph feel like spider going down pughole runway in sight about 300 feet to go need 90 deg turn more corkscrewing about 100 feet to go Im a third in and downwind at 50mph jeez the ground comes fast no pissing about stick hard back this might hurt bounce off main gear check forward ease back running in ground effect now make normal landing well better than normal for a Bantam all wheels still attached arrange truck get outa here before the nitwits arrive

APRS tracking I have trialed 2 versions in my machine. One version used the amateur network on VHF the other I used HF frequencies. VHF is unsatisfactory for the area and altitudes I operate, HF was excellent. If you want your position reports to be received on the amateur radio network your transmitter needs to be operating with an amateur radio licence. If this option is unavailable you can use UHF PRS or aero VHF. Its unlikely anyone has set up receive sites for this in your area yet so if you want the position reports received you have to arrange this yourself. Our local microlight club is interested in this and work is being done to see if we can add receivers into the existing internet backbone so that aircraft can be viewed on the web. In the middle of all this, interest has declined because microlights in NZ will be required to carry 406 PLB as minimum equipment for flights over 10 mn. Once pilots have spent their money on that they will likely not bother with anything more, which is unfortunate because in many cases ELTs do not provide the answer - took 2 weeks to find a 406 equipped chopper, and S. Fossett had 2 beacons. APRS is a patented technology that is free for amateur useage. Other systems using the mobile phone network may become the better option because most cellphones have a GPS receiver already inside. Ralph

Discone would be best, but harder to make than buy. there is nothing important about scanner aerials, you probably won't notice the difference if you just make one from the coax cable from the set, by cutting off the outer wire braiding for 24" down from the end and hang it up outside or glue the end inside a length of pvc tube. in fact you only have to 'ring bark' the outer braid at the 24" point, leave the rest intact if desired. For deluxe performance, add 2 lengths of thin brazing rod in a X formation, mounted horizontally, connected to the braid at the cut. That will give you a ground plane antenna, suitable for 50 ohms cable to a transmitter in the VHF aero band. Ralph

Surely its not that cold in NSW? These engines were designed in snow country - i'm sure if you follow the SB checks something will show up. The battery is probably fine for the job as a starter motor only draws 80 amps its not like the jabiru (theres no substitite for cubic inches) which needs a 16 AH battery. The friends problem and cures I refered earlier have been sent to the CAA (at the request of one of their field reps who was there at the time) and RAANZ so you should be able to read about it first hand - in case I missed some detail. I recall checking of the gearbox preload was done by removing a bolt on the side of the gearbox and threading in a locking pin then pulling the prop thru with weighing scales. it only took 5 mins. If You download the gearbox parts list you can see that depending on model it will have a dog type torsional vibration dampening assembly (15 deg or 30 deg) and may have a prop overload clutch as well. Ralph

Ian, It is possible the transmitter could be reacting do a mismatch on the antenna - if its only on certain frequency range the match can be corrected by changing the coax length or antenna. Its more likely to be a fault with the coax ground connection. Similar problem the other day here: Posted: Sat Aug 25, 2007 1:39 pm Post subject: Re: Radio problem! PROBLEM SOLVED!!! The BNC connector at the antenna was gounding out. I made a whole new cable for good measure, and all the problems are long gone!!! Thanks for all the advice.... Travis </SPAN>mprather(at)spro.net wrote:If you speak into the mic while transmitting, do you hear your voice (from the sidetone) through the headphones? Are other stations able to hear your transmission? With good quality? In addition to adjusting the gain, you might be able to adjust the sidetone volume if everything else appears to be working properly. Regards, Matt- </SPAN>Quote: <travishamblen> I have an XCom radio in my RV-7A and I am having some problems transmitting. I seem to receive just fine. When I push the PTT button on the pilot control stick I get a static in my headset. If I push the PTT button on the passenger control stick I get the same static (in the pilot headset) with the same intensity. When I switch headsets to my backup headset I don't hear the static when I push the PTT. HOWEVER, the problem is much worse in flight (possibly due to a louder environment); on the ground with the engine shut down the static is minimal. I have not tried the backup headset in flight. I will fly tonight with the other headset to see if this eliminates the problem, but I don't think it will. Since it only happens when transmitting I am starting to think there is a problem with the PTT wiring?? Any ideas to start me out? I will report back with the results of using a different headset. Could this be a gain adjustment needed (I can adjust the gain)? Travis Read this topic online here: http://forums.matronics.com/viewtopic.php?p=130771#130771

you get what you pay for. You do realise the 914 is about twice the price of a 3300? Seriously, theres a lot of factors and you need to say in what way you want to compare. In most approved installations, the 914 will deliver more power at ALL altitudes, because in climb attitude with an allowed prop the 3300 will not be doing more than 2900 rpm = 110 hp. You can screw more out of the 914 because its liquid cooled, the turbo keeps it going, and it can turn more eficient and variable pitch props. Let the discussions begin.....

Paul, The dog clutch ( not the slipper clutch) if it has become worn will directly affect starting because when the torque reversals occur at startup they are not absorbed by the 15 deg or 30 deg slippage normally afforded in the gearbox and the prop is able to kick back the to the crank. This shakes the engine so much that either one of the carbs falls off (not kidding) or the fuel is disprupted in the floats preventing a proper start. It was Bert Floods who told us to take the prop off to check for this, and they were right on the money there. Secondly, if your worried about the starter do the bulletin SB 912 042 You need a DC clamp meter that will read up to 200 amps if you cant find someone with one its a good excuse to go to jaycar or DSE and get one they are handy to have anyway. One thing we noticed the SB says to start the engine but you cant get a reading that quick so we assumed they really men to crank the engine with ign. off to get the reading good luck Ralph

Paul I dont own one but have worked with a few that have had the same problems. There are a number of rotax SBs on the subject esp. the 912S. The most recent case was a 912 that would crank and sputter but not pick up from rough idle. A Phone call across the ditch to your good agents sorted this (after 2-3 days stuffing about locally). The procedure was to lock the throttle to idle, remove the prop and start up. It ran like a kitten. That means the gearbox dog clutch preload was too low, requiring O/H of the box and a new 30 deg. dog if I understand correctly. This was carried out and fixed the problem for a few hrs, until the starter occasionally would throw out. We measured the cranking current per the details in the SB for the 912S and it read 69 amps so it was off with the starter clutch and now thats fixed its back to normal running. TTIS around 180 hrs. Ralph

For your stats: Rotax 503 SCSI on Bantam failure during climbout @ 950' shook rattled & prop stopped. Low compression traced to failure of little end conrod needle rollers portions of which were found in various places, and a broken ring. These were the early caged rollers design. Aircraft had previously sat around for a couple of years before I bought it and I had 3.5 hours on it at the time. I expect there would have been pitting on the rollers due to lack of regular running. I consider the 503 the most reliable of the Rotax 2 strokes especially the dual ignition (went on to loose a coil in flight 40 hrs later but those early coils were recommended changeout @ 300 hrs / 3yrs) Ralph

Reply to J430 posting: I'm getting worried about the valves / guides issue, having come across an example on Matronics which I'll copy here. The factory must know something about material changes that us field testers are not privvy to. I can smell another CAA AD if this trend continues without some proper explanation. Is it possible that valve leakage is occurring regardless of lean mixtures, but due to abnormal guide wear? Ralph Posted: Fri May 11, 2007 3:22 pm Post subject: New rocker arm bushings in Well, the old bushings were a teflon-coated bronze over a steel shell (TPFE, I believe they are known as) and for whatever reason, they failed at...or at least I discovered them failed at...273 hours. I decided not to replace them with the original style bushings, because I don't know the history of how these bushings hold up under the splash-lubricated, high-pressure (the valve spring), environment they operate in. Now to be perfectly honest, maybe nobody else has had a problem with these bushings, but I did, so I elected to try my own "shade-tree engineering" and put in oilite bronze bushings. In doing so, I decided to supplement the oil that ordinarily makes its way into the side of the standard bushings. The standard bushings are allowed (according to my owners manual) .004"-.010" side clearance. I did not change this, but I did drill a .093" hole vertically into the rocker arm, at exactly the 12 o'clock position of the rocker arm. This will allow the oil a chance to run into the hole and help lube the bushing. If anybody cares, I'll continue to report how I installed the bushings. They came 16mm wide and the rocker arm is 15mm, so I shortened them on my lathe. I had pressed the old bushings out, and after drilling the rocker arms for the oiling holes, I drilled the bushing oil holes a little larger, then pressed them into place, keeping the alignment of the holes in mind. They all came out aligned as hoped, and then I had to ream the bushings to the size suggested in the owners manual... .474"-.475". This provides for 2-3 thousandths oil clearance for the .472" shaft. I then swapped the rocker shafts side-for-side, to enable the new bushings to ride on the un-used part of the shaft. I also chamfered the sides of the new bushings to further allow oil to make its way into the oil space provided between the shaft and arm. I've got to further say that I don't know squat about teflon in engine bearings...my only use of teflon (that I know of) is frying eggs in a pan....low (relative) heat, no pressure, and the eggs taste fine. I wouldn't have eaten eggs cooked on the teflon that was visible inside the removed bushings...they looked like the frypan had been attacked with a steel spatula, if you'll permit me the kitchen analogy. : ) Again, I'm not saying that Jabiru made a mistake, maybe I just got a lemon, and if my "fix" doesn't work out, I will have no apologies to make. My engine is in a Kitfox Model IV *experimental* airplane, and that's JUST what I'm doing...experimenting. Lynn Matteson Grass Lake, Michigan Kitfox IV Speedster w/Jabiru 2200 flying w/275+ hrs do not archive

Thanks Brent, My notes from the last 50 hr for the plugs reads: "No.2 darkish, others light brown." The exhaust usually is a light gey/tan similar to the Cessna 150 that also ran 100 Avgas. Cruise EGT is 695 and full pwr 680 which is OK for the original carb tuning but on the high end for the currently published 2nd revision. For peace of mind I'd still like to know if the current spate of valve troubles is occurring to Welltite seats or a different seat material. If valves are tuliping into the heads I suppose that is a case of overlean. At last 50hr all my exh. valves were found at .008 and were reset. Inlets were good. Ralph