aro

9 hours ago, kgwilson said:

It is always the pilots responsibility for his/her own safety even if that means breaking rules. If the situation requires it I'll break away. 

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.

1 hour ago, kgwilson said:

My response has been to immediately announce turning base & tell the straight in aircraft he is No3. If he doesn't acknowledge, tell him to acknowledge.

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.

3 hours ago, facthunter said:

When you have a lot of arrivals expected having them all do a circuit is not wise. Experience has proven straight ins are not as dangerous as first considered.

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.

3 hours ago, facthunter said:

The most dangerous place in a circuit is final.

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?

1 hour ago, turboplanner said:

Fortunately our security forces don't have to rely on all social media commentators  for that.

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.

1 hour ago, turboplanner said:

Because there is a new group of players. You would know the details are not advertised.

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.

13 hours ago, Ironpot said:

all know just how easy it would be for some crazy to fly 1000 litres of Avgas into the main stand of the MCG on a match day

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.

23 minutes ago, turboplanner said:

I thought I had clearly separated GA flying from Recreational Flying. The above  comments relate primarily to GA Flying.

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.

25 minutes ago, Kyle Communications said:

in the scheme of things the path loss is not that dramatic and usually only for a very short time

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.

1 hour ago, Kyle Communications said:

ADSB in and out of the aircraft is realime millisec data refresh direct between all aircraft in the respective eqyuipments range that yo have in your aircraft. That realtime is sent to your Ipad and is usually a different colour target.

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%.

20 hours ago, turboplanner said:

ARO said:

 

CASA have been watering down the rules around uncontrolled airfields for as long as I have been flying.

20 hours ago, turboplanner said:

I think you'll find the SAOs needed to  replace those rules.

20 hours ago, turboplanner said:

No one has suggested making rules that duplicate CASA rules.

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.)

14 hours ago, Garfly said:

I don't think I understand the point you're making Aro.  I'd have thought that a threat approaching close enough for separation to be an issue would go on the useful side of the ledger. What if you're in a high wing and the airprox target is a low wing descending on you from behind, a glance at your iPad screen (as into your rear vision mirror) might be the ONLY thing standing between you and disaster.

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.

15 hours ago, Garfly said:

A mere glance updates the danger just as it does with the big semi bearing down on you in the rear view mirror.

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.

10 minutes ago, turboplanner said:

I think you'll find the SAOs needed to  replace those rules.

RAA, GFA etc fly in the same airspace as everyone else. They are bound by the same rules as GA. RAA are not free to make their own rules in that area.

19 minutes ago, facthunter said:

Report sighting and passing

You need to assume sighting isn't possible IFR. It also doesn't work for multiple aircraft inbound on the same track to the same destination - particularly when the fastest one is at the rear!

11 minutes ago, facthunter said:

Vertical separation is  the most reliable, provided you know about Altimetry and have the same BARO reference and the thing is within limits.

Vertical separation is most reliable, as long as no-one needs to climb or descend and the altitudes are available/usable. Once you need to climb or descend, an accurate understanding of aircraft locations is required.

One day I was listening on area as 4 IFR C172s departed Ballarat for Avalon, closely followed by an IFR Seminole. The IFR traffic information from ATC was entertaining. It was clear blue sky so no problem to actually separate VFR, but good luck sorting that out with pilot organized separation if it was IMC with a low icing level.

I have been flying for a few years with Avplan + ADSB receiver. These are my observations:

It's very useful IF the other aircraft is travelling in a straight line and/or you know its intentions. For example, if you are both inbound to the same airfield from the same direction you can get a much better idea of your relative positions and whether you need to take any action to ensure separation. Likewise, yesterday I was inbound to an airfield about 20 miles out when another aircraft departed on a reciprocal track. I was able to delay my descent until we passed each other so I wasn't descending into their path.

It can also provide a useful picture when you are arriving at an airfield, supplemented by radio e.g. you might "see" 3 aircraft in the circuit, plus another on the radio but without ADSB, and another on ADSB 2 miles ahead inbound. That's a useful aid to situational awareness prior to arriving.

When it's not so useful:

• If the other aircraft is not travelling in a straight line.
• Once you are close enough that separation is an issue e.g. less than about 1 mile. By that point you need to be looking outside for the aircraft. It's easy to see why controllers working with a screen use a separation standard of several miles.

It's also very tempting to try to separate yourself when there is no risk of collision. This is surprisingly difficult because when you are in reality a long way apart any change to your track doesn't make much difference on the screen.

On 07/12/2022 at 1:07 PM, Garfly said:

In its report on the tragic collision of two light-twins over Mangalore in early 2020, The ATSB observed:

 

"Had each aircraft been fitted with ADS-B IN, and a suitable cockpit display, the occupants would have received the same quality of surveillance information received by the controller. This technology could have prevented this accident from occurring ... // The ATSB also notes that ADS‑B receivers, suitable for use on aircraft operating under both the instrument or visual flight rules, are currently available within Australia at low cost and can be used in aircraft without any additional regulatory approval or expense."

I wouldn't read much into that report. IFR aircraft need separation by ATC, that is what it was invented for, but for some reason we don't do it in Australia. The report deliberately ignored that. I don't think that having additional traffic information in the cockpit (other than last resort stuff like TCAS) will make IFR safer. There have been a number of incidents with IFR aircraft trying to do DIY traffic coordination in Australia (including RPT), but the obvious conclusions are ignored.

"the same quality of surveillance information received by the controller"

Since Mangalore, ATC has been a lot more proactive trying to avoid traffic conflicts in G airspace. It's pretty painful to listen to. Basically the quality of surveillance information isn't the problem - the problem is that separating aircraft using a screen is very difficult unless you know the intentions of all the participants, can make a plan and give people instructions i.e. ATC.

You can bet if someone is shot at a firing range it won't be SSAA investigating it. Likewise, if someone dies in speedway it will be the Coroner investigating. Speedway participants will be witnesses, not investigators.

The problem with expecting RAA or GFA to investigate is that you have multiple organizations involved. RAA and GFA obviously, but the rules to avoid collisions are administered by CASA so they are involved too. Do you think RAA can realistically conclude that CASA is responsible for the accident - even if they find that everyone was following CASA rules, and the accident could just as easily involved 2 GA aircraft?

In reality, I think ATSB investigate too many accidents. It doesn't generally produce anything useful, other than satisfy a ghoulish fascination with what happened. Can you find an ATSB investigation that produced a meaningful change to prevent future accidents? As they say, it is very unusual to invent a new way to crash.  For private operations, there should be an initial assessment, and then only do an investigation if it appears that the causes are not understood, or part of a wider pattern.

Aircraft have been colliding for 100 years. We know why, and we know what to do to prevent it. CASA have been watering down the rules around uncontrolled airfields for as long as I have been flying. It might be useful to investigate and decide whether that contributed. If it is established e.g. that the RAA pilot was not following rules, maybe you would want to do an investigation to see whether that was systemic in RAA in GA in general. Otherwise, there is probably not much new to learn.

Can we please try to dial back the racism on this site?

The thing I hate most about aviation - so many people are racist at a level I don't see in any other group I spend time with.

14 minutes ago, old man emu said:

We are presently being regularly told of the actions taken by certain persons of Semitic appearance against persons often of Caucasian appearance

I don't know who is telling you that.

In fact the security services currently say the largest threat at the moment is right wing white men who hold grudges against people who are non-white, LGBTIQ, "elites", politically left etc.

There are regular attacks that would be considered terrorist actions, except that we have been conditioned to believe that white people cannot be terrorists.

3 hours ago, turboplanner said:

4 hours ago, aro said:

What does "drivers ... not of the Caucasian nor Asiatic physiognomy" mean?

Just that

4 hours ago, turboplanner said:

a trend in the transport industry which is of concern

Do you have any other explanation for these posts? There's a clear conclusion I would draw.