Ian

Where do you get your "independent research" from? Facebook or independent researchers on the Internet? The science is absolutely blindingly clear and as a theory has been ascendant since the 1980s. When you look for factual advice look to scientific journals, even ones like new scientist or scientific american there is no debate, no lack of consensus and only the scientifically illiterate believe otherwise. The Murdock press has been consistently anti-scientific orthodoxy, giving every crank and their dog a forum from which to wax lyrical. The problem is not hydrocarbons it is simply the fossil ones, coal, oil and gas.

It requires some fuel, the returns are far greater, it requires about 40-55L fuel per hectare to crop canola. The yield is 400-900L per hectare. On a 2000 hectare property that's quite a bit of oil. I'm not saying that other processes can't produce liquid fuels with net zero emissions however the agriculture route is a well understood one. Nobody will force farmers to grow crops at a loss, they'll only do it if it makes them money. There are also lot of people betting on ammonia as a fuel created from cheap solar and wind, that sounds an awful lot like the Haber process for fixing nitrogen so you have a lot of fertilizer being produced without fossil fuels. The key point being that fossil fuels are used in the process at the moment because they're convenient, the process also works without them.

The emissions reduction index from the United States National Biodiesel Board showed that the combustion of biodiesel wholly as a transportation fuel decreased total hydrocarbons, polycyclic aromatic hydrocarbons, carbon, and sulfur emissions by 67%, 80%, 48%, and 100%, respectively. There's a slight increase in NOx however this is not across the board. NOx is just an equilibrium chemistry reaction, the hotter and hence more efficient your combustion process is the more NOx you produce. Cool the flame, inject water or add some exhaust gas and you force the reaction the other way. The other option is to remove it from the exhaust. In terms of lubrication biodiesel is a much better lubricant and makes your diesel engine last much longer. If fact it beat all of the aftermarket lubricants as fuel additive for ordinary diesel for lubricating injectors. In terms of fuels competing with food crops that's an economic question which markets are good at dealing with. Basically coal and fossil fuels and cow farts are out and agriculture, solar and nuclear are in. Europe has some great resources for electrification which we don't have and France especially is madly exporting Nuclear generated power generating 3B Euro per year in exports. The key point isn't electric vehicles and banning ICE it's zero emissions, hydrids can be zero emissions if they burn a zero emission fuel, it's not cheating. While this is the sane choice which anyone with a basic understanding of maths and science should be able to comprehend, when you are running towards a cliff, simply slowing to a walk doesn't solve the problem, stopping solves the problem. Economically we're going to face very large tariffs if we don't go down this path so pragmatically we need to change our approach. The wealthy countries which buy our stuff are watching our emissions and will tax the buggery out of us if we don't comply. Poor countries which don't have these policies don't have the budget to buy our goods so telling the rich clients to bugger off will be expensive. So even if you want to say "I don't believe that sciency stuff" you're community is going to face a huge hit to the hip pocket by taking a contrary view. It's a bit like being a christian butcher in a primarily jewish and moslem community, the meat that you sell will be kosher and halal but do you believe in any of that hockey pockey? No, but you make a pragmatic business choice. Anyway planes will require liquid fuels for the foreseeable future so what is the zero carbon emission fuel of choice and what will your baby run on? Lycomings will run on ethanol however storing it in Fibreglass tanks is a bit problematic 🙂

On the fuel note, does anyone know if an experimental diesel powered airplane has flown in Australia? I think that someone in Tasmania was looking to put a Subaru diesel in a plane and I'd be interested to know how far they've got or did it all become too hard. I think that the biodiesel route is probably simpler and cheaper than the other fuel pathways in the longer term.

I'm happy to take a bet on this fantasy if you wish. In Norway 80% of vehicles are now electric, in Europe 20% of sales are now electric, Australia's stance is an outlier however we're being dragged into a carbon market. Now I own a petrol burning vehicle however I accept that at some point fossil fuels are going to be taxed like buggery and the tax breaks for electric will be pretty compelling, either that or biofuels.

The pain is necessary, to believe otherwise is naive and change needs to occur on all fronts. Unless you're completely withered you're going to see a massive change in your lifetime, which will probably lead to significant conflict and human misery. Our own bushfires have just been the beginning, the barrier reefs will be a tragedy and mass ocean extinctions due to acidity combined with warming. However the key message is carbon neutral not the death of ICE, I would guess that for cars battery powered electric will end up being the cheaper option. However all this is off the topic of airplanes. In short people will not want to give up international travel and air freight so jet fuel in one form or another will remain. There are choices however if I was looking to build a plane diesel engines would be high on the list simply because they're more efficient and can burn jet-fuel.

The changes will take a long time if the change is dependent upon building new infrastructure. For example in the graph above look at the adoption time of change that required infrastructure with end to end connectivity. Cars required better roads and fuel distribution mechanisms, electricity required distribution networks and power generation stations. For example if you had a hydrogen refueling station, how do you get hydrogen to that station? Do you liquefy it, build a pipeline or manufacture it onsite from the electricity grid. Because where you make it isn't where people want to use it. In a side by side comparison hydrogen costs up to 14x the cost of direct electrification. Now I know that these figures are rubbery however it looks like lithium batteries have already won the vehicle transport battle because the infrastructure for charging partially exists. Who's going to build a network of hydrogen stations for an unproven part of the market, especially when the range of a hydrogen car is less than a battery powered one. Now I've been a fan of fuel cells for a long time, however hydrogen as a fuel a bit of a turd, there is an alternate methanol economy which hasn't had much attention however direct methanol fuel cells currently require platinum so a breakthrough is needed. I suspect that the reason that hydrogen is being pushed is that the gas companies believe that they can produce hydrogen from fossil fuels maintaining the value of their assets as part of the gas led recovery. Weaning off fossil fuels will be very very hard. According to the Bill Gates book "How to avoid a climate change disaster" only 12% of fossil fuels are used intransport the rest are consumed making thing and heating and cooling etc. And yet we're finding the first 12% really difficult, think how we're going to do without concrete, steel, plastic and fertilizer. Even aluminium manufacture uses carbon anodes and cathodes which are consumed releasing CO2. So the one structural thing that we refine electrolyticly still produces CO2. Just look at concrete and you'll figure out how hard things will be. Anyway as I said either batteries need to get a lot better and cheaper or we need Nuclear.

While I see people mention hydrogen it's a difficult fuel compared anything liquid, I've even see people speak glowing about converting hydrogen to ammonia and suspect that they haven't read the history of ammonia safety in refrigeration. Hydrogen is high in volume and interacts with most structural metals to cause hydrogen embrittlement. In comparison ethanol is simple, there are already planes flying however it does impact your range. There's a large body of knowledge relating to making combustion engines run using it. Butanol has a similar energy content and octane rating compared to avgas and can be produced in a carbon neutral manner. Biodiesel and related process can produce jetfuel analogues which have already been demonstrated to work in turbine engines. Yes there are issues associated with things like low temperature stability but they're pretty simple to solve. As policies change to force transport to be carbon neutral things will change however there are some pretty simple solutions out there. The solution will have a significant agricultural component so I can see this benefiting countries like Australia enormously. There is a huge issue will intermittency associated with solar and wind which remains an unsolved problem. A huge amount of power intensive industry is only economic when it runs 24x7, these industries won't function with intermittent power. Storage is expensive and countries like Australia which are flat and dry have very limited hydro options. Long distance power option such as high voltage DC are expensive, about a billion dollars to supply the UK from France. Frankly I don't see anything but nuclear as being able to fill the gap in the near term.

I'll bet you 20L of diesel that you're a bit picky 😉 Though I would love a piston engine that could burn jetfuel or diesel.

One thing that I've found, especially if there's a disparity in experience between the team member is that sometimes people don't speak up when they think something is wrong/incorrect. It's a real issue for some people and cultures. Doubly so when you're flying, so in that situation always brief people, if something appears wrong or dumb speak up.

My understand is that a diluter/demand system with a mask can also be used be in unpressurized aircraft to 40,000 feet and that this doesn't require a pressurisation endorsement if your plane can fly that high. However just because it's so doesn't make it safe and risk free. There's also a good report here in relation hypoxia in flight https://www.atsb.gov.au/publications/investigation_reports/1999/aair/aair199902928/tab-abstract/ From the attached CASA document. Demand regulator: This type can be further divided into pressure demand and diluter demand type regulators. Diluter-demand and pressure-demand masks supply oxygen only when the user inhales: o Diluter-demand system: as the altitude increases, ambient pressure (and therefore the partial pressure of ambient oxygen) decreases, the oxygen flow increases such that the partial pressure of oxygen is roughly constant. Diluter-demand oxygen systems can be used up to 40,000 ft. o Pressure-demand system: the oxygen in the mask is above ambient pressure, permitting breathing above 40,000 ft but as the pressure inside the mask is greater than the pressure around the user’s torso, inhalation is easy, but exhalation requires more effort. Out of curiosity, does anyone know where the baro chambers are in Australia and how much it is to do a stint in one. It might be a good birthday gift for some pilots, especially if there's video footage. DESIGN-AND-FITTING-OF-OXYGEN-SYSTEM.PDF

All Good, it's a fair cop, the whole COVID thing is a great example of how people can grab the wrong end of the stick and refuse to believe anything that doesn't align with their point of view. I'm happy (relatively speaking) to change my mind and eat crow should the weight of evidence suggest I should do so. If there's evidence that vaccines start turning people into zombies or similar I'll reconsider my stance, but in the meantime I won't taking medical advice from Trump or Bozo on facebook. Universities, Government research organisations, and Journals tend to be good places to get information. The thing that really makes me laugh about people with conspiracy theories involving Government is that somehow they think that the same management practices which make CASA could have some overarching secretive agenda which they've coordinated across decades; think about it. Personally I'm pleasantly surprised if a Government building has toilet paper. I once worked on a project where one of my peers argued strongly for a significant change to a design against which I argued pretty strongly, however that evening I decided that yes he was right and spent the night changing a presentation to reflect his critique. The next day during the presentation I let people know that it was his design and tried to handball part of the presentation to him however he didn't say a word. Afterwards I asked him why and he said he was just shocked that I had changed my mind as I argued against it previously.

Hi All, I saw this article in the Kitplanes magazine and wondered if anyone in the community used oxygen on a regular basis and had put together their own kit or purchased a complete assembly. How much and how accessible were refills and did it sit unused or was it a considered piece of safety equipment which provided you with additional options. What size cylinders provide the most utility? I also saw this article written about the use of pressure demand systems however I can't quite see that use case in the near future. I do like the approach, qualifications and experience of the author though.

I've seen opinions and stories of black gum and varnish without a skerric of a picture or other evidence but the mention of someone thinking that they read something get's a reaction. FFS 🙂 That made me laugh but anyway I didn't think that what was written here was gospel and people had a bit of a clue how to use google, so for those with the interest here's a link with the claim and another one All in the pursuit of better practices I suppose 😉 For those who like to read, there's also a good article on Ethanol and Octane rating. How-Does-One-Measure-Ethanol-002.pdf

There an interesting video on Germany's WW2 efforts to increase power when they only had access to low octane fuel. It's good because it references NACA reports relating to specific combinations of Water/Methanol mixtures. There's also a video on a system for current generation forced induction airplanes which can't currently use mogas. Not that I think the cost is reasonable however it does provide a significant operational safety margin.

A simple test for ethanol is to get some food colouring, put it in pure petrol it should remain unmixed. If the fuel has ethanol it will colour the fuel. To be sure test first with some e10 and pure fuel. I'd be interested if someone finds contaminated fuel. https://backcountrypilot.org/forum/using-food-coloring-to-test-for-alcohol-in-gas-11431 Our airplanes engines are really dumb and unreliable compared to car engines however low levels of contamination shouldn't impact the RON to any significant extent, air temperature has a greater impact on RON and you don't complain about contaminated air. Unleaded AVGAS is expensive and unlikely to appear, why would you use it if mogas is fit for purpose for 80% of the fleet? https://generalaviationnews.com/2011/03/16/10-mogas-myths/ The bottom line is phase 1 is that some people will adopt avgas early and leverage the benefits they perceive and gather knowledge. Phase 2 will be those watching the first group and will adopt their practices if they don't see them falling from the sky. The Phase 3 group will never be convinced and will continue to put avgas in their tanks until it is phased out. From what I'm seeing, phase 1 has occurred and we're in the middle of phase 2. Actual infrastructure is being built out and at some point will likely dominate 100LL. The main driver will be price without excise mogas is currently about $1.30 L which looks pretty attractive. I thought that I read somewhere that some engines were being given an extra 1000 hours TBO when run on lead free fuels.

The testing which was conducted found that this wasn't necessarily as requirement for the Lycoming engines which were approved. Testing was conducted over a range of temperatures where fuel was heated in the tank prior to the flight. My understanding is that the EU provided blanket approval for all planes to use mogas if the engine was approved and there hasn't been any significant impact as a result. Someone with more knowledge than me might be able to comment. The requirement for in tank pumps relates to the engines which aren't on the approved list such as IO360 with bendix injectors. The high temperature associated with these were found to cause vapour lock.

It's a market, there are a number of flying schools which run mogas using very large volumes. If it works for them and is an approved fuel so be it. They keep a pretty close eye on their supply chain. If you can afford to buy avgas and can manage the negatives both in terms of costs, health risks and deposits so be it.

It's what you believe. Not what's supported by science. In an engine designed for it, each octane rating number increase will provide an efficiency dividend of approximately 1%. The key word in this sentence is designed, you need to increase the compression. My wife used to own a Subaru B4 which was designed for 100 Octane and detuned to 98 for Australia. At full boost with twin turbos in hot conditions it would ping and retard the timing so I would put some e85 to increase the RON. It was a fun car however turbos, RON and power go together. Non turbo vehicles are a different matter. The energy content of 91, 95 and 98 is essentially the same, E10 has a slightly lower energy content however it increases the RON. Your car is designed for 91 octane and might get a tiny increase in efficiency due to ignition advance however not on the scale that you're talking about. It is was actually true the fuel makers would be trumpeting across the airwaves as their margins are higher on 98. What you're seeing is possibly what's called a confirmation bias where you see what you want to see. A better way to test would be to get your wife to fill the car up and not tell you what fuel is being used. That being said, your car might be different from all the other cars but it's your money and if it makes you feel good do it. Personally I don't like parting with money when there's no logical reason. Alcohol in fuel can make sense at a particular price point and if rated to do so it doesn't hurt your engine using it, in fact it has a number of benefits such as lower EGT. It's not the devil, just another fuel. Also real studies indicate that he impact on range isn't as high as the figures you believe. This this link provides also provides a good summary. By the way the boiling temperature of Ethanol the alcohol that is used in E10 is about 78C, so boiling in the tank might be a bit of a stretch, vapour lock maybe. Now to counter your argument I've give you a bit of maths. On average 98 is 20% more and to travel 335000km you would have put about $50,250 of 91 fuel through it as $1.50L. If you put 98 through the engine it would have cost you $10,000. Now a RAV4 with the 6 cylinder engine with only 200,000km is being advertised on carsales for $14,000 and they might accept $10,000. So by using the cheaper fuel you could be driving a car with 140,000 fewer km and you also get to pocket whatever you sell the car for. That's the logical and rational choice. However we've digressed a bit from the key issue of a list of where you can get Mogas ;-)

The key rule is put in the engine what the manufacturer says is OK, you might take a risk based upon a risk/value assessment to vary from this however Avgas isn't magic. There are people who believe that putting 98 Octane fuel in a car that only requires 91 is a good thing. This view isn't based on science it's based on a feeling just like people who think putting Quartz crystals by their beds protects them from cancer. If people want to spend money on bits of rock so be it. Similarly people who put more expensive blends into engines can if they want. But is may not be a view supported by science or the manufacturer. However Leaded fuel is toxic to the point that children raised near leaded fuel outlets had significantly lower IQs than those who lived further away so it is a bad, bad thing, if you can avoid it I think you should. If you think it's good you've probably spent too much time near a bowser. (Oddly enough the guy who invented leaded fuels also invented CFCs) Now those of you who can claim tax credits for mogas can also save another 43 or so cents per litre which is significant. Also contrary to popular belief Australian auto fuels are standardized and conform to international norms.

Attached is a list of Lycoming engines approved to run Mogas. Given the current state of affairs I suspect that Mogas is the fuel of the future as it Suits most engines in common use Is easy to test for ethanol contamination. (Just use food dye) Has a higher energy content than AVGAS Is not a neurotoxin For engines which can't use Mogas due to octane requirements I can see STCs for MW-50 in your future. For engine at risk of vapour lock, positive pressure fuel pumps similar to the automotive ones are also in your future. SI1070AB_Specified_Fuels.pdf

I'll use one of the online dictionaries definition which probably aligns with what I was thinking, "characterized by grotesqueness, extravagance, complexity, or flamboyance", I could l have used baroque, byzantine, complex, complicate, complicated, convoluted, daedal, elaborate, intricate, involute, involved, knotty, labyrinthian, labyrinthine, sophisticated or tangled but you get my drift. It appears to be significantly more complex than it needs to be to perform the function which is required, especially given modern technology.

Yes, the principles are applicable to piston aircraft. If you need more range your best bet is ground effect. :-) The pilots of WW2 knew this.

Thanks for the input and information, I'll have to do some reading, It would be nice to see some research which indicates that there is actually a quantifiable benefit in this regard. From what I've seen there's the hypothesis that "Integrated training" provides an outcome however I haven't seen anything which indicates that this is actually true. If there's no supporting evidence it would be nice to see both sets of requirements aligned. Simpler, less paperwork for the bureaucracy to maintain and lower cost. Given the recent experience with building inspectors the separation of functions would provide a benefit, especially if testing the school didn't have the ability to cherry pick testers. For example CASA should provide a pool of independent examiners chosen at random based upon location and availability. I also noted that ICAO Annex 5 is related to units. I'd really like to see this area progress and the imperial spagetti go down the toilet. I do understand that there's a lot of people who are used to dealing with these things however once that bandaid is ripped off things become much simpler. When I was at Uni many years ago I worked with a surveyor and had to deal with miles, feet, chains, links, inches, decimal inches and a whole other lot of rubbish. It still pains me when I seen calculations based on foot pounds, gallons and other rubbish. To me that all belongs in the "Vintage Aviation" category.

So from the above, there's no research demonstrating the advantages of either approach, so logically they should have the same baseline requirements. The fact that they don't would indicate it is most likely to have occurred as part of a sweetheart deal to advantage section of the training community and disadvantaging others. The structure that I was alluding to was the whole requirement for a "school". The reality is that to fly a plane I need two things, an understanding of the theory and practical instruction. Theory can be imparted using a variety of methods using textbooks, classroom time, videos or other mechanism. A variety of mechanisms can be used to assess this knowledge however examinations are simple and accepted practices. Personally I prefer reading textbooks and journal publications however other learn most effectively using other methods. Flying instruction is performed by your instructor (who CASA agree is competent and up to the task) and assessed by a flight test and practical examination by an assessor, there's no requirement for a school per se. With COVID the concept of what a school is has become far more fluid as more online resources have been used. For instance one piece of knowledge which appears to be poorly understood by a number of pilots is fuel consumption optimization and how it relates to altitude. I've attached a good paper on the subject, the issues is confused by turbine engines because these engines can't throttle efficiently. Piston Airplane Cruise Performance.pdf