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CASA don't do any assessment for the basic class 2. Basic class 2 boils down to a yes/no question to be answered by your GP: do you meet the standard for an unconditional commercial driver license. By applying a condition, your GP has said no and the basic class 2 is not available. CASA will do their own assessment if you want them to - it is the normal class 2. The standard for a regular class 2 is less strict than a basic class 2, but you may need to provide more supporting information. The basic class 2 a cheaper path for uncomplicated cases, not a lower standard.

Every engine needs an efficient intake and exhaust system to deliver rated power. The difference between Rotax and other makes is 1) Rotax state it explicitly and 2) They supply an optional airbox. Is the intake system on your average Lycoming as efficient as the one use to measure rated power? Who knows - but odds are it isn't. So your average Lycoming probably isn't delivering rated power either.

I found comparisons for Rotax vs O200 installed in a Kitfox. The consensus seemed to be that the Rotax was about 20kg lighter installed. I also found pictures of Cessna 150s with a STC for a Rotax engine. The Rotax was quoted as 18kg lighter, but the aircraft was fugly with the extended nose to maintain CG. You can save a lot of weight running a smaller engine at higher rpm for the same power. But from the Rotax 912 to Jabiru to the PT6, new engine designs have only really been successful when they have been paired with new aircraft designs. For an existing design, it's much easier to live with the limitations of the existing engine.

When they were designed, but they are old designs now. It's instructive to see what happens when people suggest replacing the smaller engines with similar power Rotax engines. It turns out that the Rotax engines are lighter, which means a longer nose to get the correct CG, which means new spin and stability tests etc. Basically it is possible to build smaller, lighter engines with newer technology but you need to design a new airframe around them (which is exactly what we have seen with the Rotax engines). Pretty much all of them. It's interesting to read about the durability testing they do on new auto engines. They need to know if there is anything that will break, before they build a million of them. Typical seems to be: 300 hours continuously at max RPM, wide open throttle 10-20 hours at 10% over redline, WOT 400 hours varying between peak torque and peak power in 5 minute cycles, WOT 2000 hours idling to verify oil delivery at idle speed Thermal cycle testing, where they chill the engine with coolant at -15C. When the engine is at -15, start it and run at peak torque, WOT until it reaches redline temperature. Then stop it, drain the hot coolant and run coolant through it at -15 until the engine is back to that temperature. Repeat 1000 times. Every time you find way to fail an engine in development and fix it rather than have it fail in the hands of a customer is a win.

The problem with auto conversions is all the other bits that you have to add and the things that are different to a car installation. Auto manufacturers probably spend tens of millions validating the cooling system, gearbox etc. An auto conversion needs: - a PSRU - a custom cooling system - maybe e.g. the sump needs to be modified to be sure of oil supply in different attitudes. Particularly if the engine is installed backwards relative to a car installation - climb power becomes the equivalent of full power *down* a steep hill - not something that cars commonly do The type of people who do auto conversions also like to make their own tweaks, maybe to increase power e.g. based on race tuning or increase perceived reliability. None of these changes get the type of testing that the car installation gets. It's not the engine that is the problem - it's the changes you need to make to put it in an aircraft, and the cost to do that development properly. Car manufacturers can afford to spend the cost - aircraft manufacturers can't. You just can't recoup the costs with the size of the market.

That's my point, aircraft engines don't have nearly the same development resources available. And given the scale of production, car manufacturers can't afford to have anything like the failure rate that we see in aircraft engines. There are still problems - but massively fewer than in aircraft engines. Compare the hp/capacity for an aircraft engine vs. car engine. 100% power in e.g. a Lycoming is relatively low for its capacity. Car engines in development are tested at 100% power for hundreds of hours continuously. It's just a myth that they can't do that. Problems in auto engine conversions for aircraft are most likely due to the parts that are different or don't exist in a car e.g. cooling, PSRU. Auto manufacturers also spend millions validating the cooling system - no-one can match that in an auto conversion. There have been huge advances in engine reliability in the last few decades, but aircraft engines have hardly changed. That is because of the cost of development, not because they are more advanced than auto engines.

I don't know whether per km is the best way to measure reliability, particularly since car reliability probably improves e.g. with more highway km at 100km/h. Would you say the same engine is more reliable in a fast aircraft than a slow one? Even so, 1 in 10,000 hours is probably more like 1 in 5 aircraft experiencing a failure before 2000 hour TBO, rather than 10,000 hours on 1 engine. So using your calculation it's probably equivalent to 1 in 5 engines failing before 200,000km, which I think *would* be bad enough to seriously embarrass a car manufacturer. Any failures are also more likely to be maintenance related, e.g. not changing oil, coolant, hoses etc. in a 10+ year old engine rather than the engine itself. I am really referring to car engines from the last 10-20 years - not older engines e.g. from the 70s and 80s which were definitely less reliable.

Look at the number of cars vs. the number of aircraft. The reality is that if car engines were as unreliable as piston aero engines, there would be cars broken down everywhere by the side of the road. The CASA Jabiru engine failure study quoted a failure rate for Continental and Lycoming i.e. the "good" engines at 1 per 10,000 hours. Car manufacturers can't afford anywhere near the level of unreliability that aircraft engines get away with. The publicity would kill the manufacturer. Car manufacturers need reliability. If there's a way to cause a failure they need to know about it. They put their engines through tests that an aircraft engine would be unlikely to survive. Aircraft engine manufacturers just can't afford the R&D costs that go into a modern car engine. They don't have the numbers.

Ha, I wish! That works as long as you don't need to set an alarm, schedule a meeting, calculate someone's age, calculate interest, display the time... basically most practical uses of time.

I doubt it was an issue for this particular flight because it has more effect on slower aircraft, but: Do not trust fuel calculations from the EFB apps unless you understand exactly how they select the winds for the calculation. I know one of the commonly used apps in Australia makes a poor wind selection for fuel calculations. It only occurs in specific weather patterns, but you can fly from A to B back to A and it will give you a tailwind in both directions. I have finished a flight with significantly less fuel than expected, and it was due to this tail wind both directions scenario.

If your aircraft has a MTOW of 1000 kg and max load factor of 4g it means the the wings can produce 4000kg of lift. If you stall at 100 knots at 1000kg and 4g, it means that at that speed you can't overstress the wings. However, at 800kg, 100 knots still gives you up to 4000kg of lift, but that is 4000/800 = 5g. The wing still sees 4000kg and is OK, but other parts of the aircraft see the higher loads e.g. seats, baggage compartment floor load limits are based on the same 4g limit and might be damaged. The G load applies to the whole aircraft, not just the wings.

The Mangalore accident is different because it was under IFR. The ADSB issue in that case is a diversion from the real problem: we operate in a stupid, stupid system where ATC do not do the job ATC was designed to do - separate IFR aircraft. For some reason the entire industry is opposed to ATC separation of aircraft under IFR, away from the major centres. But ATSB are not allowed to criticise the regulator, so they come up with a reason it was the pilot's fault, and the issue of ADSB traffic displays as a decoy. I'm not an IFR pilot, but my understanding is that IFR generally fly fixed paths for approaches etc. that guarantee terrain clearance, and don't have the freedom to manoeuvre off track to avoid other aircraft. So what is an IFR aircraft supposed to do if they're in IMC and their traffic display shows another aircraft on the approach path, between them and the missed approach? That's why they need ATC - ATC have procedures, and a unified plan to manage all aircraft. Not one plan per aircraft, with no-one knowing exactly what the others are going to do. Here's another IFR incident. A 737 and A320 near Launceston. Cocked up self-separation under IFR badly enough to end up in an ATSB report, despite being able to see the other aircraft on an in cockpit traffic display: https://www.atsb.gov.au/sites/default/files/media/1573068/ao2008030.pdf IFR aircraft need ATC separation, not DIY.

It's not real time. It's close to real time, most of the time - where the exact meanings of "close to" and "most of" are variable. When you see an aircraft you can pickup up e.g. a turn maybe 10-20 seconds before it is obvious on the screen - if you are looking at the screen regularly. Inside 1-2 miles, the situation can change a lot in 10-20 seconds. Personally, I use the traffic display approaching an airport. By about 3 miles I should know who is there, where they are and what they are doing. At about 3 miles I put the screen away and work visually. Sometimes I might use it longer if someone else is inbound at the same time, but it's only really useful to verify that you are passing behind someone. Obviously that plan only works for one of the aircraft. If you're still trying to track traffic on the screen in the circuit area you are flying blind. In the case where it would be really useful e.g. when you are in the circuit and someone is flying a straight-in, the potential delay makes it useless or dangerous - you really do need to judge visually or based on the other pilots radio calls. The more useful thing in the circuit is traffic announcements through the headset. I haven't had any yet that have been significant, but I can see the potential.

I think it boils down to having takeoff and landing flight paths that cross is a bad idea. It's tempting to put your faith in a magic gadget but there is a reason separation standards are increased when working from a screen instead of visually. Once you are close enough that collision becomes a risk, you need the real time information that comes from seeing the traffic. I have used Avplan with an ADSB receiver for years, and the reality is that it helps with the "alert" part of alerted see and avoid, not the separation (unless you already have separation e.g. vertical or a couple of miles.)

The theory that he describe as the "pixie dust theory" is basically saying that lead compounds on the surfaces stop them from sticking together (micro welding). I'm not a welder, but if you told me that contaminants on the surfaces could stop a weld from sticking I'd say it sounds quite likely.

Of course you can, if their decisions are inconsistent. Which seems to be a large part of the criticism.

It doesn't take much to leak. If the clamp doesn't expand, when the engine gets hot the rubber is compressed inside the clamp and you are relying on the resilience of the rubber to return to it's former size as it cools and maintain the seal. Over many cycles the rubber doesn't return perfectly to the original size and can leak. With a spring clamp, the clamp expands when the engine gets hot, the rubber stretches, and the clamp helps the rubber return to the original diameter and maintain the seal when it cools. At least that's how it was explained to me when I had a problem with a hose leaking when cold.

My understanding is that the coolant hose clamps need to be spring type. The aluminium expands and contracts more with heat than steel, and a steel clamp without springiness will damage the rubber and eventually leak.

CO2 detectors have become popular to help assess ventilation and therefore COVID risk. Indoors in crowded places (or even badly ventilated workplaces and schools) CO2 levels can get quite high. If CO2 level is e.g. 600ppm ventilation is pretty good. However CO2 levels approaching 2000ppm are not uncommon, which means you are breathing in a lot of what other people are breathing out.

In an emergency, you can break rules if required for safety. Someone landing ahead of you off a straight in approach is not an emergency. You create the unsafe situation by knowingly turning base in front of them. Instructors locally were complaining about pilots assigning sequence numbers to other aircraft. I was sceptical that it happens. I guess I was wrong.

Bad idea. You are not ATC so you can't tell other aircraft to do anything. All it takes is for the other aircraft to file a report: "I was on a straight in approach following another aircraft. After I made a broadcast at 3nm an aircraft on downwind announced they were turning base and told me I was number 3. I was forced to go around, and there was a breakdown of separation as a result" You are 100% on the hook for illegally issuing instructions to other aircraft and knowingly creating an unsafe situation. The reality is that even though aircraft on a straight in are supposed to give way, there is very little they can do for separation other than go around. The aircraft on downwind has many more options, so usually they can adjust to let an aircraft in on a straight-in.

I just looked it up... the max difference is 5 hPa. So the maximum altimeter difference between someone on local QNH and someone on area QNH should be about 150 feet. http://www.bom.gov.au/aviation/data/education/awp-area-qnh.pdf

No-one is suggesting QFE. Area QNH is probably sufficient, it shouldn't differ from local by much (from memory there is a limit, where they have to split the area and use 2 area QNH values)

I don't see what context I missed. In a circuit you can fly closer in, further out, adjust your base turn... many options. One time I was in a Gazelle sharing the circuit with a C172. They took off as I turned crosswind. I kept the circuit tight because they were much faster. After 3 circuits I was turning base as they turned final. It's much harder to manage e.g. a C172 behind a Gazelle on a straight in approach. Straight in approaches are a bit of a disaster if you have a lot of traffic (without ATC). They still seem to be uncommon so I'm not sure where your experience with significant traffic would have come from. As soon as someone goes around you have an aircraft doing a regular circuit, so you have straight in approaches mixing with circuit traffic which makes it worse. It tends to fall back to a regular circuit.