Markdun

Seems like a lot of confusion here. I have lithium batteries in my planes for several years now. No problems. I do have Powermate voltage/current regulators, a 15A fuse in the AC side of the regulator, & 150A fuse at the battery terminal (like a motor vehicle). My lithium batteries are ‘ion’ as opposed to lithium metal, and ‘iron’ as in ferrous. They have their own BMS and are marketed as being drop in replacements for lead anchor batteries for motor bikes and race cars. They weigh nearly nothing. Both are mounted on the firewall on the engine side. My experience is that they deliver exceptional current while maintaining voltage for starting the Jabiru donks. They turn the first few blades through compression very slowly, but then you have the engine whirring at over a 1000rpm. They really spin it up once the battery warms itself up a bit. On colder days it may take a bit more to get the battery warm. The batteries can sit for months and still appear fully charged with over 13.2V. In my set up the batteries charge at the Powermate regulated rate of a bit over 8A after startup and it all settles down in a few minutes to 14.2V and 2A for my EFIS/EMS etc. My only concern is whether the cranking power is a bit too much for the Jabiru flywheel. As to fire risk, firstly, my understanding is that this comes mainly from lithium metal batteries. Dendrites off lithium metal grow across the anode andcathode to give you an internal short circuit. Second, some batteries come in flexible bags and damage to these bags can also cause internal shorts. Third, the BMS should prevent charging or discharging currents in excess of the batteries capacity. Fourthly, I use fuses in both the charging and discharging circuits, & the Power matE prevents the alternator doing a runaway current job... as well as the fuses. Fifthly, my batteries are mounted forward of the firewall. Finally, I have had a Jabiru alternator do a complete meltdown in the air (blue smoke in cockpit) about 10 minutes after takeoff, just following a quick fuel and bladder stop after a 2.5 hour trip (so it’s not like the battery was deeply discharged). That set up had the standard Jabiru/Kubota tractor voltage regulator and a lead-acid battery. On landing we found the copper windings on the alternator had dropped molten copper onto the carb, & the reason the blue smoke cleared was the alternator went open circuit. I have noted that the Jabiru engine installation manual does not recommend a fuse in either the AC circuit from the alternator to the voltage reg. nor a bartery terminal fuse. On my view those fuses, whichcost a couple of dollars, ought to be considered essential. I was lucky; the molten copper could have started a fuel fire from the carb; or instead of the alternator burning out, I could have had an actual in cockpit fire from the battery wiring burning or the regulator which were mounted aft of the firewall and forward of the instrument panel..... and directly above the 67litre fibreglass fuel tank.

I flew today. OAT on the ground 8C. Plenty of humidity & unstable gusty air. Carb temp 2C on warm-up, so precautionary use of carb heat used and carb temp rose to 12C for take-off (with no carb heat). At cloud base 4500’ OAT was 3C and carb temp 8C (no carb heat). Carb heat used on descent to keep carb above 20C. Cabin heat would have been nice, but appropriate clothes were sufficient,

Yep. I have a Rotec TBI carb on my Jabiru powered Corby. At cruise I get a narrower EGT spread than my other Jab powered plane with a Bing carb. At WOT it’s just as bad as the Bing.... the rear cylinders go lean and the front rich unless you back off the throttle a bit and drop 100rpm, It’s nice to be able to adjust the mixture, but the Bing is pretty good & if I had the room firewall forward in the Corby I’d go back to the Bing just for simplicity. In both my planes I run an MGL EMS, monitoring rpm, oil T & P, carb temp, coil temp, fuel pressure and flow, 4x egt & cht, oat, voltage and current. It’d be nice to have a knock and vibration sensor. I had manifold pressure in a VW powered plane and this was useful in setting a nice cruise throttle position but I find I set the throttle just with fuel flow. A friend is developing his own engine monitoring system for his Jab powered Drsgonfly. He intends having a large glass screen display. But it is taking him quite some time to get it all together.... he has just received his printed circuit boards from China.

Thanks for that, I'll check them out.

I have 150Amp slow fuses on my batteries as a main fuse. The only unfused wire in the plane is 5cm of cable from the positive battery terminal to the fuse mounted on the battery box (the AC from the alternator is also fused). It frightens me that people fly with a potential arc welder via the starter cable! The starter motor clearly draws less than this. I started at100A, but this blew on the third start. I also monitor current drain/charge using an Arduino module (not in the starter circuit though) which doesn't use a shunt but an Hall effect sensor. Works for me and just plug and play with my MGL EFIS/EMS. On my home power system (off grid with 13kWh lithium batteries) I monitor power & battery state of charge via a 'Coulomb counter', also Hall effect. Mine goes up to 300A and quite a few kilowatts, but you can get them for smaller currents and power. Only a few grams in mass, and cheap.

Here is an oil analysis on my Jab 2200 by ALS in Australia. I do it every 50 hours. Around $35. I agree you need a baseline. Seems easy enough and not that expensive. I've found filter chops less satisfying; only ever saw a few aluminium millings in the break-in period. A surprising result is that even after hours of running with oil temps less than 70C, still no water in the oil! 1592132544241_Mark Dunst_Unit193393_Petrol Eng_Severe_34971739.pdf

Try a new needle jet instead. The mixture at most power settings is set by the gap between the needle jet and the needle. The needle jet is brass and can wear from the needle. So if you gradually have increasing richness, try a new needle jet. If that is still too rich, try the next size smaller, then if too lean polish the bore of the needle jet with brasso until you get your desired mixture. This avoids fligging around with the float level.

Bruce, I've read a bit about the extremes some of the RV guys go to to get an extra knot or 2 by reducing cowl inlet and outlet. Anyway a common thread is that the outlet, or more precisely just before the outlet, is very important. Stuff like gascolators, airboxes battery and even engine mount tubing can reduce the air flow and in particular affect port and starboard sides differently. It would seem to me that as the inlet pressures are the same it has to be the outlets. I note your EGTs are very close for a Jab. I'm still getting a spread from 640C to 700C. I don't see CHTs up around 150 except on 30+C days with two people in the plane and after a long slow climb out, mostly they are between 120 and 130.

Mark, I do not think it is as simple as many have replied. No matter what you use, the key question is whether it will fail under what load, the number of cycles for failure, & its mass. I'm sure the 10mm 304 1×19 stainless wire with 12.6mm 316 stainless turnbuckles which keep my yacht's mast upright with a breaking strain of around 30kN would work with your rudder cables, but it would be tad heavy. Stainless steel does work harden more than the steel alloy use in AN fittings. Stainless fittings with thread are also more likely to gall. Further, stainless fittings immersed in seawater can also corrode leaving them looking good, but very weak. Nevertheless, many aircraft have wire cables of stainless, some have galvanised (same for yachts, though increasingly yachts have plastic such as dyneema replacing wire rigging. My 11m yacht has 5mm dyneema braid for the rudder circuit & it has loads easily 10 times of what you would get in a light aircraft ). Both my aircraft have stainless cables and a mixture of AN turnbuckles and stainless ones. My scratch built Cygnet has stainless turnbuckles on the rudder circuit (20 years, 1000 hours). Each one has a safe working load of 5kN. The ailerons and elevator circuit has AN cadmium plated steel turnbuckles. All cables are terminated on a thimble with Nicopress sleeves. My Corby Starlet (40 years 300 hours), previously VH registered, also has stainless cables. Turnbuckles are all AN steel ones (no turnbuckles on the rudder circuit). However the cables are all terminated by swaged stainless fittings and were supplied by a certified aircraft cable supplier. Having built several aircraft (successfully) my advice would be to stick with what the aircraft designer specifies. If you want to change it, discuss with the designer. And remember the rule for assessing whether to add something or make it stronger than the designer specified. Hold it in your hand & throw it up in the air. If it stays up, it should be added. if it falls down it was never meant to fly and should be discarded. Cheers, Mark

I agree with all the previous comments to the effect that the quoted claim 'seven times more likely' is most likely hogwash. In any research, raw results, like these, may be nothing more than a random chance event. There are statistical techniques, robust ones, to test whether the results are 'significant', and usually they are not significant unless the probability that the results are merely random chance is less than 5%...the so-called 95% confidence. Why haven't the ATSB used them? Either they haven't engaged a statistician, or they have and they are too embarrassed to publish the outcome. There are lots of dishonest studies, particularly where there are commercial or other vested interests. For example, I have seen low quality studies with very small sample sizes that found no 'significant difference' between the control and the variable which are then used to justify a 'no effect' finding and then used to undermine the credibility of studies with very large samples. There are some good books on this detailing the tactics activities of Big Tobacco and Big Pharma.

Of-course as soon as any organisation says 'we take privacy very seriously', it means they actually don't. But in my view privacy is overblown much of the time, and things like the electoral roll, vehicle registration, & even tax paid & declared income should be publicly available on line. The Privacy Act only applies to certain, large and medium sized businesses and organisations. It doesn't apply to small businesses or individuals. It seems to me that the issue is the liability for aerodrome charges. And the answer to that question is what is the legal contract? In most cases the contract between you and aerodrome operator will be that set out in some public document, such as ERSA. By landing, you have partly performed one part of the contract and a court will decide from this that you have agreed to the published contract. There have been cases litigated for pay carparks where the terms and conditions of the contract are on the other side of the boom gate...the courts sided with the car driver that as they couldn't know the terms & conditions before entering, the act of entering did not constitute part performance, so no contract and no liability. However, ERSA does indicate whether charges apply, so I think it could be argued, that as long as the details are discoverable, then you are contractually obligated to pay, whether or not RAA-AUS passes on contract details or not. I have one proviso: I would expect that the contract and liability attaches to the pilot who chooses to land there, NOT the registered operator of the aeroplane. I don't think the pilot has the power to enter contacts for the aircraft owner. AVDATA. I'm not sure whether the demand payment on behalf of the aerodrome operator, in which case they are agents. If this is the case each payment and the contract remains between you and aerodrome operator, in law anyway. They may also be assigned the contract if the terms of the original contract has a term that provides for this. Lots of companies put this provision in their contracts so they can sell bad debts to dubious debt collectors. But, my point on this is that I think most people have an obligation to pay the aerodrome operator, not necessarily AVDATA. The fact it sends invoices is besides the point. Invoices are not necessarily obligations to pay or a debt. I know of some people who pay aerodrome operators directly and still get demands from AVDATA, with whom they have no contract, so they just ignore them. So called penalties for late payment. Only courts can impose a penalty. Even traffic offence fines do not have to be paid until a court orders it. Generally you voluntarily pay an 'infringement notice' to avoid the court ordered penalty. So, any term in a contract that has a fine or penalty will be struck out by a court as invalid (void actually). If you fail to pay on time, a court will order you pay the outstanding money plus interest, plus the the other party's costs for beach of contact. But parties to a contract can make reasonable estimates of cost for foreseeable events like late payment. ..And most people are aware that the banks recently lost a big group action on late payment charges for credit cards because the stipulated amount bore no relationship to their actual costs. Just sayin.

Nev, my apologies if you took what I said applied to you. It was actually a reference to my age. When my kids were 6 or 7 they used to think that dinosaurs were around when their grandfather was young. Now, my grandkids think the same about me. My point was that the tension between those that rely on more recent technolgy and those that rely on older methods is not new. When i was sailing in the '80s using a sextant a 'fix' was within a 5nm radius or there abouts...you adjusted your navigation accordingly....i didn't try a night passage through a gap in a reef of only 1 to 2 cables wide. ..I hove to 10nm away & waited for daybreak (to be woken by a French navy patrol boat). Others with transit satellite nav & radar went straight through (& didn't have the experience of receiving a rousing cheer & waves from the french sailors when I stumbled naked into the cockpit to investigate the noise of the patrol boat). I would sail straight through now too with GPS. I think you are wrong on GPS unreliability now. ADSB relies on GPS, as do lots of other things. If the GPS system goes down, then there are far bigger problems than a guy in a light aircraft. And even if it did, as an RAa pilot you just have to find a reasonable paddock to land. I rely on GPS for my nav in aircraft, on the sea and bushwalking. I still carry paper maps and an orienteering compass but have not had to use them for ages except to teach others or to re-assure myself that things are tickety-boo. I have two aircraft; both with an MGL Xtreme EFIS/EMS as the main instrument and with a 'steam' ASI 'back-up'. I would be happy to replace the stream ASI for a secondary electronic ASI/ALT but the value is not there to justify it. There are some inflexibilities in the MGL Xtreme, but overall they are fantastic. Cheers, Mark

Ahh, Skip, its called the 'astronaut syndrome'. Back in the mid 1980's, pre-GPS & only a few dinosaurs left, quite a few sailing boat owners sucuumbed to this syndrome, with their chart table/nav desk surrounded by dials, lights and switches and transit satellite navigation, probably with a clip-board and check lists. When I was in Nukalofa I think there was only 4 of us out of 30 cruising sailors that only had a compass, log & sextant (& charts) for navigation. Much discussion then that modern sailors wouldn't know how to use a sextant if the transit satellite receiver failed etc. Seems not much has changed regarding attitudes...but tech certainly has. ....i met a guy at 1770 a couple of years ago on a very fast 50' sailing cat who had sailed from Hawaii via lots of islands with just an ipad with downloaded charts for navigation.

I'm also with Skippy. ..my primary navigation instrument is the right eyeball mounted just below my forehead. After 60++ years of service with just one replacement lens I think that is pretty good. (The left eyeball, being only good for things less than 1m away without the monocle, is reserved for the instrument panel). I'm not that keen on voice alerts and warnings...one of the joys of flying is that my wife doesn't like flying and stays on the ground. ..would seem silly to have an artifical replacement that would detract from the serenity. I was taught that if I ever landed 'wheels up' in a sailplane that once the aircraft stopped, to immediately jump out and pace the distance of the landing roll....vis 'I did it intentionally to see how quickly it would pull up'. We did always fly off lawn though.

I've got a real nice electric vario in my Cygnet. I do miss the lovely beep beep beep of the audio it made in a glider. I can't hear it now over the noise produced by the iron thermal (or my 'too much engine noise hearing').

How many of us have lost rc gliders? Like Bruce I lost one, but about 20 years ago. Hooked it up to the bungee, let it go. ...ooops, forgot to turn the power on in the glider. ..not to worry it will just come off and land nearby.....wrong! It came off the bungee in a nice right turn straight into a thermal. I lost sight of it as it disappeared into the base of cumulus about 2500' above. No lithium batteries though, just nicads. For those wanting a 'soft start', how about a mechanical decompression lever....works ok on hand start diesels? Or compressed air, shotgun cartridge...that would be cool. I'm now getting worried about fire from my lithium batteries; i think I'll mount them in a stainless insulated box with a quick release pin attached to a servo & temp sensor so if the tempersture exceeds, say 120C, it automatically drops out of the aircraft. And if it looks like a difficult outlanding, I could manually pull the pin to jettison the battery before 'landing'. Thinking of avoiding battery started fires on crashing, how many people have a battery fuse mounted on the battery box or positive battery terminal as motor vehicles do? I also wonder how many lead acid batteries explode from the explosive mix of H2 and O2 generated when they are charging? Or structural and corrossion damage aircraft caused by the weight and acid electrolyte? I've see at least one 24 xxxx registered aircraft with cracking on the firewall from the lead acid battery mount....it was quite difficult to rectify.

Mike, the stator windings melted. We removed the stator completely before another flight because we couldn't exclude a short circuit developing in the melted stator windings which could lead to more smoke & hot stuff dripping on the carbie. At 2900rpm the alternator can obviously deliver a current that exceeds the capacity of the stator windings. The starting of our diesel firefighting pump with a very tiny lipo battery also starts off slowly and as Old Koreelah said, then it cranks it with some violence. No landing lights on my planes, and my LED strobes are hardly likely to warm up the battery.

Bruce, be careful with the human voltage regulator. My comment about a destroyed Jab stator comes from experience on a delivery where the Jab/Kubota regulator failed and the voltage started to creep up towards 17V (this is with a lead acid battery on my side of the firewall just near my toes). The aircraft had a nifty switch in the cockpit (Alt) that open circuited the charging wire from the regulator. So I did what you do; as soon as the voltage reached 14, I switched it off. But I also switched it back on when the voltage dropped to 12.5V (it had a big panel with old instruments)...big mistake. ...blue smoke etc at 7500' and drops of molten copper dripping on the carb (we discovered that on the ground). Skippy, the slow start is only from an early black Jabiru starter motor which is a bit underpowered. I think its just that the lithium battery doesn't deliver the current until it warms up a bit...the same as a lead acid battery...but to warm those batteries up I understand you roast them in a camp fire for 15 minutes -- well that's what I saw on the TV series Bush Mechanics. The other thing is that lithium batteries' voltage doesn't drop away as you extract energy like a lead acid battery. I'm not that fussed about it as starters are pretty robust. ..i once drove about 250m in 3rd gear in a Mazda on the starter motor across a floodway on the Nullabor when the distributor got wet. And I've seen a few times people endlessly cranking a Jabiru refusing to start (because the rpm was enough for the ignition system to fire)...This would be far tougher on the starter motor compared to the few seconds it takes to get my motor going.

I assume you have installed a sliding track from a front car seat for your wing attachment so you can easily adjust your CoG. I wish I thought of that when i installed a lighter Jab engine to replace a VW, requiring moving the engine forward 50mm, new engine cowls, and then 1kg of lead in the tail because 50mm forward was too much!

I just splice in an automotive blade fuse holder on one of the two wires that go from the engine's alternator to the voltage regulator, and put in a 15A fuse. These fuses are designed for vibration. I don't use the glass tube type fuses in an aircraft as the unsupported fuse wire inside the glass tube can fatigue break from vibration. The Powermate website probably has a diagram of the details.

I think the big practical issue is the charging of the Lithium batteries. If you forget to turn off your master switch and find you've a flat aeroplane battery you can't just 'jump' start from your car as you will exceed the charge rate for the lithium battery (depending on the battery management system in the lithium battery). Or if you hand start, or manage to get a start from a nearly flat lithium battery, the standard Jabiru voltage regulator will also not regulate the charge current and this could see the battery's charge rate exceeded, or the Jabiru's stator destroyed (if you have no fuse in the AC side), or both. The Jabiru/Kubota voltage regulator might also have a too high upper voltage .... one of mine was at 14.4V which was a bit over the 14.0V recommended for the lithium battery. I've installed the Powermate regulator -- it regulates the charge current to a max of 8 Amps and my voltage never goes above 13.9V now. The big difference I've found in use is that on a cold morning when you press the 'start' button the starter rotates the engine to the first compression and really struggles to move it through TDC, this occurs on the second compression too, but then the battery seems to finally wake up and gets the message that it is required to deliver lots of Amperes and voila, the engine spins like crazy & starts. And it does deliver lots of Amps....I had to increase my battery fuse from 100A to 125A.

Modifications to the air intake on the side of the cowl (& its position) made a big difference to EGT spread on my Bing carbed 2200. So I concur with Hyundai. I ended up settling on a port mid height (ie. widest part of cowl just under the join) about 75mm forward of the firewall. I also have a small deflector on the forward side of the hole that extends outward about 1 cm. After lots of experimentation this seemed to give the best results at cruise & WOT throttle settings. Although I have to throttle back at WOT (rpm ~ 3100 FF 23lph) to avoid exceeding 700C egt on my rear cylinders (particularly #4) at the cost of about 50rpm, & at cruise (15lph) my #4 runs at around 640 to 650C when the others are around 710-720C. No data on manifold pressure unfortunately. Why the inlet matters I don't know as I would have thought the air filter and the little rubber flap on the air filter box would remove any significant pressure effect on the carb. Carb inlet vanes made bugger all difference, except when a 'vane' obstructed one of the pressure sensing ports of the Bing. My limited experience on a Rotec carbed 2200 with a J&H filter attached directly to the inlet drawing warm cowl air with no carb heat 'a la' many Rotax 912s is totally different. EGTs are evenly spread irrespective of carb rotation. Carb temp has never been less than 30C even on a 5C OAT day, and has seen 50C+. I do worry about vapour problems as there is no float bowl in this setup.

Can someone explain why a compass is still important when in most cockpits we have 3 or 4 gps devices (EFIS, handheld gps, tablet/ipad, phone) & its unlikely all will fail? If the gps system collapses there are far bigger probs afoot than landing in a paddock 'lost'. I have a 'steam powered' ASI as a back-up, but know I can fly & land the aeroplane sans all instruments. And I carry a handheld compass, but really, if all my gps went out, I'd either land as soon as possible or navigate by eye, the sun & terrain.

Would love to. Waiting for the changes from CASA that will enable us to install a cheap version easily. I have an AIS marine transponder in my yacht (simliar to ADSB but without the ground stations/satellite links &;a lot slower). Its great...ships 'see' you, and if they don't you can ring an alarm in the bridge through their vhf radio. I did see an official marine rescue vessel once going 15kts sternwards from the AIS...they had made some installation error.

Just to be different I like to use the area frequency. My airstrip is about 5nm south of Lake Bathurst and Canberra controlled airspace LL is at 6500'. I have 3 other airstrips within 2nm of mine; one is commonly active with gyros. Also I'm directly on the flight path for military aircraft going backwards and forwards from Canberra to the secret airbase Albatross at Nowra, and many of their helicopters and fixed wing aircraft fly at around 1000'agl or below.....my normal circuit height. On a couple of ocassions listening in to the class G area frequency (which is actually Canberra Approach east) I have heard vhf aircraft circling at 4500 waiting for clearance into Canberra, and a quick call to the ATC has enabled us to maintain better seperation. I find listening in to the appropriate area frequency gives me better situational awareness, including on cross country flights and it also makes it easy to terminate or extend Sarwatch. However, the military is another beast. I have had to take evasive action to avoid a blackhawk when I was on downwind. I have emailed them about this but have not even had a reply...no idea what frequency they were on. I even suggested they could land at my place for a coffee so we can better arrange how avoid each other. I thought the old concept of ALAs was ditched many years ago when the rules changed to require pilots to make a decision whether they could land/take-off from a location and that ALAs are now only relevant because some insurance company's will only cover the plane if it is operating from an ALA???