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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.

I don't believe that. What do you do if you have someone on a straight-in doing 75 knots behind someone doing 65? And then someone (or more than one) goes around? The circuit gives you a chance to see other aircraft, figure out where you are in the sequence, and adjust spacing. That is all more difficult with straight in approaches. Multiple aircraft in the circuit can manage spacing well enough that runway occupancy becomes the limiting factor for full stop landings. Straight in approaches put multiple aircraft on final, with less ability to manage spacing, for a longer time. It's hard to see how that doesn't increase risk.

The restrictor sizing is confusing. The Rotax installation manual specifies 0.5mm and also #35 jet. It seems that jet numbers can be either size or flow rate so #35 jet could be 0.35mm, or 35cc/min = 2.1 l/hr. My guess would be flow rate since there is a separate 0.5mm size specification. The flow rate is influenced by the shape of the passage, not just the size. How did you measure the return flow rate? Timed flow into a container?

The difference between an ASIC check and secretly investigating pilot and student pilot license holders is that the results of the ASIC check have to be known to the pilot. The security forces like to keep this stuff secret. So the ASIC is basically useless to them - they will do their own separate investigations, keeping the results to themselves, and will not rely on people volunteering for a check.

And you think they will voluntarily submit to a check? The critical question is how does not having an ASIC stop someone who is prepared to break the law?

If you were organizing one of those missions, it would be very useful to know which of your members was under suspicion. What better way than to have them apply for an ASIC, and anyone who is denied would not be allowed to be in contact with other members? Of course, the authorities are not stupid so they would be very aware of this. The irony is that they are unlikely to deny an ASIC, to avoid tipping people off. Much better to just let the ASIC go through and monitor student pilot applications etc - which I am sure they do. How does an ASIC actually stop that from happening? There are hundreds of airfields without security, you can learn to fly overseas etc. The reality is for anything smaller than passenger jets it is much easier and more effective to go to Budget and rent a truck.

GA and RAA operate under the same rules, with a few exemptions for RAA under specific conditions. RAA have no power to impose penalties greater than wagging a finger, all they can really do is point out if you are not following the conditions for the exemptions, at which point the CASA rules apply to you and CASA can impose penalties. There is no difference between GA and RAA under common law i.e. negligence. CASA doesn't seem worried about being sued. There are various cases where it would appear to be possible, however suing parts of the government doesn't seem like something lawyers are inclined to do.

I guess things weren't as under control as they looked. My impression is that he was waiting... waiting... until it was upright before he could safely eject.

That seems hard to assess without actually flying tests with 2 aircraft flying various manoeuvres and logging the data. Come to think of it, I probably could log data from a Raspberry Pi and look for gaps in the ADSB returns from all other aircraft and see how long they were... I'm not against ADSB. As I said I use the display myself on Avplan. But we are flying VFR, and when it comes time to mix with other traffic at short range e.g. the circuit, we need to look out the window and apply visual separation - NOT look at a screen. Yes, it can be hard to spot an aircraft e.g. on base against a complex background, but the screen is not a substitute.

From the literature on diversity antennas: top- and bottom-mount antennas .. reduce the potential for antenna “shading,” which helps prevent target drop out during turns and maneuvers. An optional top-mounted antenna also comes in handy during ground operations, when a bottom-mount mount antenna might not have clear line-of-sight to receive ADS-B ground station signals or transmissions from other participating aircraft. The designers of the system say that a single antenna can have drop outs and shading, and may not receive signals from other aircraft. Significant enough to require 2 antennas on larger aircraft. I'm not sure why you think this is so unlikely.

Yes I know... on Avplan the ADSB targets are green and the network targets are blue. But there is no guarantee you receive the ADSB broadcasts. They work on a frequency that is easily blocked by aircraft structure. So e.g. if a low wing aircraft with the ADSB antenna on the bottom turns towards you, placing the whole aircraft between you and their antenna, maybe the ADSB stops updating. Your own aircraft structure can also shadow the ADSB signal. Some ADSB systems have an antenna on top as well as on the bottom. These are designed for more reliable air-air signals rather than the air-ground design of regular transponders. But they are more expensive and probably not regularly installed on GA aircraft. Like I said, I have seen the green air-air ADSB target about a mile behind the blue air-ground-internet-ipad target. Most of the time the ADSB target will be up to date (although how frequently does the display update is another interesting question). But its not 100%.

If you can explain what you were suggesting then? The areas where RAA are self administering are pretty well defined. They don't include rules of the air. RAA are a small part of aviation and they operate in the same airfields and airspace as the rest of GA. They can't use their own set of rules. (Technically I suppose you could have a RAA rule requiring a minimum of 3 legs of a circuit be flown, but I doubt that is what was intended when CASA abolished that rule.)

The problem is that there is always a lag. It's unavoidable. You say ADSB updates every second, but that update isn't necessarily received. Avplan will display traffic less than 90 seconds old - which means any position displayed could be up to 90 seconds old. SkyEcho will have similar logic, but I don't know how many seconds. Unless you have dual external antennas on top and bottom there are probably blind spots on your aircraft. Probably behind you, if the device is in the cockpit. I don't know the specifics, but I suspect at ADSB frequencies, the receiver can't see through metal structure any better than you can. So the picture it is displaying is always an approximation. Worst case, aircraft could be more than a mile from the displayed position. Again, this is something I have seen. An aircraft was showing 2 positions, the one received via the internet, and an ADSB position. That's not uncommon, but usually the ADSB position is in front i.e. more recent. This time the ADSB position was about a mile behind the internet received position. So for some reason (e.g. antenna shielded by structure) the ADSB update wasn't received. So once you are working with traffic at close range (the circuit etc.) you need to see the traffic. It's Visual Flight Rules - you need to separate visually. ADSB is like the radio - its an aid, to make finding traffic visually easier. If you have traffic behind you that you can't see, you need to trust them to be looking out the window so they can see you. And you need to give the traffic in front the same courtesy. No, it is not like a rear view mirror - that is the point. A rear view mirror is real time visual information. ADSB is information from some time in the past - maybe 1 second ago, but up to e.g. 90 seconds ago. I'm not suggesting that these systems shouldn't be used. They provide useful information and I will keep using it. But they are not a magic box. Like any other system, they have limitations. Understanding the limitations is the key to improving safety rather than degrading safety.