Markdun

This is what I use. 0‑15PSI /4" Pressure Transducer Sensor Output 0.5‑4.5V/0‑5V for Water Gas Oil | eBay Output is linear....0.5V is 0psi, 4.5psi is 15psi. It Does need a regulated 5V supply. I tried a 0 to 10psi model but it failed almost straight away, so hence the 0 to 15psi one, which has given 100hours of no fault operation on a Jabiru engine with mech pump and facet boost pump. My display range is 0 to 7.5psi. (And there we go again with archaic units of measurement,)

I know of one problem caused by fuel pressure monitoring on Jabiru and Rotax 4 stroke installations — when the electric facet pump is switched off the fuel pressure drops close to zero for a second or two until the poppet valves in the mech pump on the engine start working. No-one without fuel pressure monitoring has reported this issue. It’s the same logic as Trump has when claiming that increasing testing for Covid increases the incidence of the disease.

I strongly disagree with your statement that being certified and tested over a long time means nothing. In the certified world faulty design or parts result in an airworthiness directive, owners bitch and moan about it but it makes aircraft safer. Am not aware of the sick cow fable.

 

The battery isolation switches rely on a spring for the disconnect just like a solenoid so I don't see any difference if they become welded. If the master solenoid was failing in certified aircraft there would be an airworthiness directive.

 

Farm/heavy equipment need after market battery isolation because while most circuits are cut by solenoid (often a long way from the battery) the alternator remains connected to the battery 24/7. Faulty alternator, dead battery BTDT. A master solenoid positioned AT THE BATTERY just like the certified aircraft will give that same complete isolation.

Thruster 88 it seems the rest of my reply didn’t make it. But I wasn’t responding to ‘certified and TESTED’, but your previous statement which was ‘old and certified’. I maintain that just because it was done that way in the past, and even if it worked, it’s sometimes worthwhile to look at alternatives. The ‘old certified’ isolators I have come across probably worked reasonably well (‘worked’ as meaning providing reasonable safety), but they weighed a substantial amount. But I think the safety provided by a battery fuse provides similar safety for a big weight saving, and if I’m doing a power off out landing, not having to turn off the battery isolator is one less thing to distract me from getting my landing just so.

The sick cow fable. Farmer A who had a sick cow attended the local annual field day. Farmer A explained to another farmer, Farmer B, about the sick cow’s symptoms. Farmer B responded that he had had a sick cow with the same symptoms and that the generally accepted approach was to treat the cow in a certain way. The next year Farmer B saw Farmer A again at the annual field day and asked A how it went with the sick cow. Farmer A responded that he did what Farmer B suggested, but the cow died. Farmer B then remarked that his cow also died when treated that way too.

Sorry, been absent from this discussion for too long. Is that your 150A fuse?

That’s two fuse holders. The bottom one has a 150A fuse (starter motor), the top one I think has a 50A and goes to the master switch on the panel and a 25A circuit breaker.

WAIT

The next french thing to give us the shiitss is their TIME in Metric.

Even the French refused it, Point blank refusal !.

100 seconds a minute.

100 minutes a hour.

10 hours a day

What does this mean for the length of hours, minutes and seconds?.

A second will get slightly shorter. Minutes will be a bit longer.

And hours will take much longer. Metric hours are 2.4 times the hours as we know them now.

spacesailor

You forgot the 10 weeks to a month; ten months to a year.

Another possibility: a reliable remote control. I have a weighted, spring loaded lever next to my right knee, connected by a wooden rod to the battery's earth terminal. (The actual connection is the rounded tip cut off the brake lever of my first bike- a Speedwell - which slides forward to connect the earth cable with one engine mount nut.)

Despite the very light spring pressure holding it there, it has reliably carried starting current for a decade.

 

I have the battery behind the firewall, technically in the cabin, but being LiFePO4, I trust it more than a lead acid unit.

Old Koreelah, here is a photo.

Pubs are the worst. I go in and ask for a half litre of beer, and get the response ‘ do you mean a pint?’. ‘No, a half litre, 500mls’. ‘How about a schooner?’. And now I’m thinking of a multi-masted sailing vessel where the formast is shorter than the following masts. So I ask, ‘do you sell beer in ‘firkins’ or ‘pins’?, as I now could really do with 1/10 of a pin of beer? And then the barman gets shirty, ‘are you taking the piss?’ No, I say, it seems despite this being a metric country you want to use old British units of measurement. You will find ‘firkins’ and ‘pins’ are real, legitimate, but ancient, measures of beer, like pints. How about some claret instead of beer? ‘OK, a small or large one? ‘WTF does that mean; Do you ever buy petrol by the ‘small or large’? I was more thinking of a hogs head actually.... sometimes it’s just so difficult to buy stuff!

BTW my aeroplane has a wing span of 52 cubits and a MTOW of 3009 D cell batteries.

For those interested in aeronautical units, it’s quite an interesting story as to why UK (& Australian) aircraft ASI is in knots, but the USA use ‘mph’, whatever that is. The answer is about the number of seats in fighter-bombers (money cost), workload and the value of aircrew (human cost). The US didn’t care about any of the costs.

A solenoid requires power to operate of course. The isolator I used in my aircraft is the removeable key type. A proper make/break switch. All the wire in my aircraft is tefzel...no auto style wire at all. The battery in the sav was right down the back the first port of call is the isolator then everything forward of that is controlled. It wouldnt matter what you had as a isolator if the battery burst into flames. You are most likely to have a severe fault forward of the isolator . I like the big clunky switches that give me a open circuit...I ahve seen too many solenoid/contactors locked shut in my time

 

You can wire it like the picture above no issue but like on any heavy machinery they still have that final part that isolates the battery completely..thats what I like

Agree

This is how it has been done on all certified aircraft since the dawn off time, a combined master/alternator switch allows all electrical power (battery and alternator output) to be shut off in fire or forced landing situations. Not sure how manufacturers are handling the self exciting permanent magnet alternator types found on jabiru/rotax machines.

[ATTACH type=full" alt="images (5).jpeg]55972[/ATTACH]

I’m sure this set up is reasonably safe. But just to be clear: the logic of a system being ancient and on ‘certified’ aircraft means nothing. It’s the same as the fable of the farmer with the sick cow.

I will always have a battery isolator within reach of the pilot in any aircraft..its your only true safety if there is a fire...first sing of smoke then kill the supply to and from the battery.

Mine in the girlfriend was mounted on the pax side on the front crossmember within easy reach while I was flying

I’m no expert, but: if the isolator is a an electrical controlled solenoid even once turned off, you still have power to the isolator/solenoid control switch. If its a mechanical switch, it means you either have the battery in the cabin or a bunch of large heavy copper wires in there with you that will still be live too, or a mechanical link to the isolator if it’s remote from you. And if your electrical fire is due to a short in the AC side of your charging system and/or the voltage regulator, isolating the battery will not affect this. Finally, assuming an electrical fire is due to a wire overheating and burning the insulation on the wire & then cutting through your wingspar, that would be due to excess current... which would be prevented by an appropriate sized fuse or circuit breaker. There is one scenario I could contemplate, and that is a lightning strike. Andeven then, I’m not sure an isolator would help. I experienced a lightning strike on a yacht...it vaporised the vhf antenna, the current flowed down the antenna coax to the vhf radio, which caught fire, releasing all the magic blue smoke that makes all things electronic work, and there to the ground bus and to the engine to earth in the saltwater through the gearbox and prop. All, and I mean ALL, electrical items connected to the negative bus, switched on or not, was toast. FWIW & that’s not much, I use an old aircraft battery isolator solenoid as a 200A relay on the yacht to power the electrical anchor winch. Finally, that smoke in the cabin might not be electrical, it just might be that your trusty plastic oil catch can decided to spray 50ml of old engine oil onto your exhaust (don’t ask)!

Yep its cheap...I made my own temp sensors for oil and water for use on the RDAC in the Girlfriend..they work a treat..far cheaper than the MGL ones. I just got some throw away original temp sensors and drilled out the guts and epoxied the LM335 inside with the appropriate cables and ran them to the RDAC...works perfect and very accurate

Water? Do you have an espresso machine in the cabin?.... now that would be style, although require more landing stops!

I make up my own CHT probes. Just bought some J or K thermocouple wire (can’t remember which),at one end expose the wires and twist together, then crimp into an appropriate, other end plugs into the RDAC. For EGT I buy $12 Chinese probes and mount them in a Jubilee clip with a 5mm stainless pull rivet (remove the pull shank and insert the 3.2mm egt probe into the rivet). Oil pressure & fuel pressure are 5v, 3 wire probes $25 each, as is the Hall effect rpm sensor & the Arduino current sensor. Only fuel flow sensors are expensive, but then I took an old Navman fuel flow out of retirement. I compared it to the Red Cube and could find no performance difference once calibrated.

Actually I have 3 fuses in the engine bay.A 150A for the starter motor, a 50A for the supply to the cabin and everything else, & a 15A on one of the AC wires going to the voltage regulator. I did have a 100A for the starter motor , but it blew, so I upped it to 150. The 150 and 50 amp fuses are mounted on the battery box with one large wire about 12cm long going to the positive terminal of the battery. I copied the set up from a friend’s Tecnam where we had to change one of the fuses which had corroded through (plane left outside in the rain by training school). The fuses in the AC charging wires is the one supplied with the Powermate regulator. It’s just a standard automotive inline blade fuse. BTW don’t use the fuses with a wire in a glass tube; the wire bends and work hardens with vibration, then breaks. Yeh, I know the Jab engines don’t vibrate, but I do have a friend who has an engine failure because of this.... the fuse was to his high pressure fuel pump on an EFI. Only use fuses where the fuseable element is supported.

Mark based on your post, I've been trying to locate the most suitable fuse for my battery (small, lightweight). My electrical mates think 150 A is overkill for my a J2.2. Are your Jabs 4s or 6s (and would that make any difference to the size of fuse needed?)

 

In trying to relocate this thread, I came across a related discussion a few years back with this interesting contribution from a well-respected source:

https://www.recreationalflying.com/threads/battery-isolator.23440/#post-264636

Actually I have 3 fuses in the engine bay.A 150A for the starter motor

Thanks Markdun. The LM355 is sold as a temperature IC I know. Do you turn on the carby heat when you think the temperature is going to zero?

Yes, particularly when warming up the oil on those cold frosty mornings after the fog has lifted.

I’ve never had icing in the carb in either with the Jab motor or the VW, both with CV Bing carb’s mounted in similar places at the rear of the motor & just below it. My VW set up had a ‘T’ there on the inlet runners with a flange bolted to the crankcase which kept it warm like the Jab inlet. Still I’ve known of people who have landed on a railway track wrecking their undercarriage, saying it was due to icing. So I’m cautious. Same for vapour in the fuel.... not so much for the Bing carb which has a reasonably large float bowl to separate out the vapour, more for the Rotec TBI carb I have on the Corby.... never experienced it and don’t want to!

RF guy, I suppose people use the LM335 because most commercial engine monitoring systems allow for it as a plug and play. And it’s cheap and readily available.

Bruce, Radiant make a cheap fuel gauge with a sender attached to the outside of a fibreglass tank. In my view you can’t have too much fuel remaining info, but if you are down to the last 10litres ie. the dregs, you ought to be finding a place to land rather than looking at a fuel gauge.

I was flying a delivery of a Tecnam from WA to the east coast and we had that very long leg from Kalgoorlie to Forest with a forecast of some headwind. It was an unknown aircraft to me so I figured the resistive analogue fuel gauges and the digital fuel flow s as rough guides only, particularly so as I had to have the LAME that ‘fixed’ the fuel tank leak by removing the evidence of the leak by cleaning the fuel stain, re-do the job. On filling the aeroplane for the first time I was rewarded with an avgas shower getting into the left seat. Anyway, on the flight to Forest every 15 minutes I did a quick calculation of estimated fuel burned and fuel remaining from our 100l full tanks at Kal and compared this to the 3 gauges on the panel and my flight plan. All pretty much correlated. It would have been nice if the previous owner had connected the RS232 serial output from the GPS to the fuel flow meter so I could have played a bit with airspeed to find the lowest fuel burn per nm. The owner/passenger in the right seat was a bit amused; there were plenty of airstrips to land at, but having to flag down a train and organise a refuel would take weeks. We arrived at Forest with over 35l remaining, mainly due to true airspeed cancelling out the light headwind.

Markdun, it seems that you have a carby temperature gauge and you find it useful. Do you use it to determine when to use carb heat?

Bruce, yes. I just used one of the spare ports on the MGL and hooked up an LM335 to it. It is inserted into the boss on the opposite side of the throttle butterfly shaft of the Bing carb. And yes, I use it to assist in determining use of carb heat as a sort of prophylactic against icing, though more often I use carb heat to cool down the EGTs sometimes. Ditto for the coil/ignition unit. My thinking was that as the MGL RDAC has the ports I may as well use them and the LM335 are only a couple of dollars.

I am going to add a bit more here. This is just from precautions in high power electronics.

 

If an arc gets going, it can burn or ignite almost anything. That's dangerous. If whatever it burns is not self extinguishing, that's bad also.

 

The inductive nature of the alternator output circuit might behave as a good welder. Remember simple stick welders are power supplies with inductors in series . It would depend on the alternator winding, mag circuit, all sorts of things.

 

This sort of problem is hard to solve with a fuse or circuit breaker. (This fact has been covered in other topics on these forums.)

Why ?

Because the 40 amps going into a battery is the normal. That current is turned into chemical energy. All is good.

Of course 40 amps going into an arc is not normal

 

But a fuse or CB cannot tell the difference .... 40 amps is 40 amps

 

The alternator behaves like a current limited device . So, there is some energy limit to the arc.

 

The battery current output is only likely limited by the wiring.

 

So, an arc with energy coming from the battery is more likely to blow a 50 amp fuse because the battery can supply 500 amps to blow it fast. It depends on the maximum electron density that can be got at the arc point, and the battery wiring size.

 

This problem of the fuse not knowing if there is a fault or not is sometimes mitigated with source and load gating.

I will make an example that suits this one: TWO current points are measured.

If the current measured leaving the alternator is NOT the same as the current measuring going into the battery, well then you have a problem .

 

So, care must be taken in design not to permit arc paths to sustain.

 

Lightning can do damage in electronics because the high voltage pulse permits an arc to establish, and then the supplying circuit goes on happily supplying current to the arc. ... Hence the need to meter the destination of the source of the energy to ensure it is going where it should.

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'll sell you a carb ice alert, adhesive paper - five bucks.

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,

anyone using the Rotec TBI fuel system on their Jab ?

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.

You really need all 3, filter, magplug (if fitted) and oil sample to get the full picture:

• the filter and mag plug show the accumulation of the wear over the time frame since the last change/clean
  
• oil samples are a snapshot at the time of taking the sample, they are subject to variations due to incorrect sample taking processes
  

The oil sample results are also limited in the size of the particles that are detected. All elemental analysis (Fe, Cr, Al, Si etc) is limited to about 8 micron in size. The PQ is ferrous material in the 10-200micron range. All the bigger stuff is not reported unless it is visible in the sample. The filter catches everything bigger than about 10-20micron (chewed-up O-rings, piston pin plugs, brass thrust washers etc) and the mag plug catches the magnetic particles that are floating past (more important in engines with gearboxes).

 

They are like an insurance, you hope that you never see anything but you will be glad you checked when you do see stuff.

 

Oil analysis, filter inspection and mag plugs can only detect failures and abnormal conditions if they happen over time. A rod bolt failure, dropped valve, conrod/bearing failure etc cannot be predicted with this type of condition monitoring, unless it is preceeded by abnormal running conditions that do show up in oil sample results (excessive oil temps, fuel dilution).

 

The one value of the oil sample is the oil condition indicators. The ALS report is pretty poor in that respect, there are very few oil condition indicators (only fuel and viscosity). I like to see the viscosity at 40 and 100deg C (standard for engine oils is 100, not 40), the oxidation, nitration and sulphation. The ALS report also doesn't contain any of the additive package elements (Ca, K, Mo, Mg, Zn, B). Additives can change from batch to batch or over time, potentially causing unintended results in some engines (leaching of Cu/Al from oil coolers is a common problem). Or show an incorrect oil used.

I'm using KOWA, same price, twice the results:

Thanks for that, I'll check them out.

It will be about 100 amps rendrag. I figure this from 1200 watts and 12 volts. The 1200 watts is bigger than my starter motor, but I think they went a bit higher later. Similarly, the 12 volts might be a bit high for a lead-acid battery while its cranking.

A 100 amp shunt can certainly be used for a bit more than 100 amps. The blurb will say something like " 75mV at 100 amps". It will only produce 7.5 watts of heat at 100 amps.

I have a LiFePO4 battery with a hobbyking 90 amp plug and I reckon this will be ok but I haven't tried it yet.

You can easily buy 100 amp shunts to work an ammeter. A few dollars from banggood.

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

I bought a factory zero timed Jab 2200, to replace the Jab 1600 that I put in the Corby years ago. The replacement was also years ago. When I got the engine I also got the Instruction and maintenance manual. Tyhis gives a good run down on the Bing carbie.

I had mine reconditioned recently and since then it has been running rich, so I decided to lower the needle in the fuel metering system. Easy job, just remove the top and the piston and the needle needs to be turned 90 degrees and moved to the new groove location. That doesn't work, the needle is free turning and will not disengage from the spring clip. Looking down the piston I see a large screwdriver slot, so I remove the screwed in part. Lo and behold it is holding the needle in place and the needle is noting like all the Bing manual depict. There is only one groove for the spring, not 4.

Leith at Jabiru tells me that it has been this way for years, even before my engine was sold to me.

I wonder if anyone else has tried to re locate a needle, or did they have the correct info in the engine manual?

Try a new needle jet instead. The mixture at most power settings is set by the gap between the needle jet and the needle.

I bought a factory zero timed Jab 2200, to replace the Jab 1600 that I put in the Corby years ago. The replacement was also years ago. When I got the engine I also got the Instruction and maintenance manual. Tyhis gives a good run down on the Bing carbie.

I had mine reconditioned recently and since then it has been running rich, so I decided to lower the needle in the fuel metering system. Easy job, just remove the top and the piston and the needle needs to be turned 90 degrees and moved to the new groove location. That doesn't work, the needle is free turning and will not disengage from the spring clip. Looking down the piston I see a large screwdriver slot, so I remove the screwed in part. Lo and behold it is holding the needle in place and the needle is noting like all the Bing manual depict. There is only one groove for the spring, not 4.

Leith at Jabiru tells me that it has been this way for years, even before my engine was sold to me.

I wonder if anyone else has tried to re locate a needle, or did they have the correct info in the engine manual?

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.