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View Full Version : E190 near collision Mildura May 16 - ASI bulletin 56


Utradar
16th Jan 2017, 23:42
Missed GA aircraft by 200' and 0.125 nm at 500' turning final. 81 Pax

Is there something wrong with our alerted search methods in uncontrolled airspace??


What is it going to take?? :ugh:

The name is Porter
16th Jan 2017, 23:57
Like opening your eyes and looking? Or communicating on the CTAF?

I'm not sure how this could be avoided other than looking out?

The Green Goblin
17th Jan 2017, 01:02
Fly a jet into CTAFs porter?

When youre above the light aircraft and and with less than flaps 2 in a jet, they can be very tricky to spot blending with terrain below you. Not to mention the workload still in the flight deck. It's not until you're fully configured with a stable FPA and forward vision, plus the major workload complete that you can see the little buggers. This usually coincides with turning final or less than 5nm from touchdown.

Plus quite often the lighties are transiting coastal outside of the aerodrome vicinity, but within conflict of a jet on approach. They are VFR and are not on frequency.

Capn Bloggs
17th Jan 2017, 02:54
Like opening your eyes and looking? Or communicating on the CTAF?

Like not doing warp speed onto Final from 3200ft at (approx) 4.5nm. How was he expected to spend a fair amount of time looking out for the EJet while doing that approach, or how was the crew of the Ejet was supposed to pick him up, head-on, when he was in that position?

At least give us a chance of picking you up...

And get that Final call back out to 5nm where it belongs...

Utradar
17th Jan 2017, 03:32
Have a good look at the limitations of 'see and avoid' in the ATSB publications 1991 to be exact. Combine that with the complexity of a jet flying a circuit while trying to avoid 'weekend warriors'.

The important 'bit' is how do we prevent the next one??

Utradar
17th Jan 2017, 03:33
Porter, you don't fly a jet do you?

After reading the report, it appears the ATSB highlight the importance of an alerted search. What happens when that fails which can be case at these uncontrolled airports? The chances of radio issues (turned down, not on the correct frequency, not in the location broadcasted) can occur leaving a jet 'blind' to traffic in the area. There's a huge difference in professional airmanship vs someone who flys very little which is more likely OCTA at regional airports. The use of TCAS as a primary method of alerted search is also wrong (CAAPs Alerted search) due to limitations with TCAS.

Where is CASA on this issue??

RobShan
17th Jan 2017, 03:43
Paradoxically, in this case, heads out of the cockpit scanning visually may have delayed the Embraer crew becoming aware the conflict aircraft.

The PM on board ZPJ commented that during the visual circuit they changed the focus of their scan from inside the cockpit to outside the cockpit. They suspect that XGA was probably displayed as other traffic on their TCAS before they received the TA alert. However, there are no company procedures specific to the use of TCAS at non-controlled aerodromes. https://www.atsb.gov.au/publications/investigation_reports/2016/aair/ao-2016-106/

If the other aircraft did not have a transponder, the two aircraft may well of come a lot closer to each other.

drpixie
17th Jan 2017, 04:24
However, there are no company procedures specific to the use of TCAS at non-controlled aerodromes. Shock-horror!!

I'm all for sensible procedures, but isn't is very bureaucratic for the ATSB to hint that having more mindless junk in the ops manual would have improved the situation?

sunnySA
17th Jan 2017, 06:30
Certified Air/Ground Radio Service anyone?

Captain Nomad
17th Jan 2017, 07:06
...AFIS...?

The name is Porter
17th Jan 2017, 07:19
Fly a jet into CTAFs porter?

No, I don't.

Porter, you don't fly a jet do you?

No, I don't.

I fly aircraft into plenty of OCTA aerodromes, when I hear them coming in I give them a wide berth.

Well what do you want? A tower? A radar/control service to the ground? Stump up the cash and you can have either or both of them :ok:

Lead Balloon
17th Jan 2017, 07:36
Surely an ARFFS before either of those! :ok:

Utradar
17th Jan 2017, 07:38
Porter, read the report dumbo ☺️ Not everyone gives them a wide berth, obviously.

Your post shows that you're completely unaware at the workload of flying a jet in a circuit and the encounters that jet pilots have with unbroadcast traffic which I would say is kinda risky, wouldn't you?

If you think safety is expensive, try having an accident da da

Lead Balloon
17th Jan 2017, 08:32
You need to get your company to implement "procedures specific to the use of TCAS at non-controlled aerodromes." :ok:

Capn Bloggs
17th Jan 2017, 09:12
Certified Air/Ground Radio Service anyone?
I see Ballina's starts on the 1st of March. :ok:

Snakecharma
17th Jan 2017, 09:24
Leadie,

How about this.

Flight crew notice.

With immediate effect the following procedures specific to the use of tcas at non controlled aerodromes are implemented.

Within 30nm of destination non controlled aerodrome.
- TCAS - OFF

In the tradition of what you can't see can't hurt you turning the tcas off is a procedure specific to operations in non controlled aerodromes and reduces the reporting rate of near misses, as you can't report what you didn't see :)

Lead Balloon
17th Jan 2017, 10:01
Job done! :D

Compylot
17th Jan 2017, 10:35
No, I don't.

I fly aircraft into plenty of OCTA aerodromes, when I hear them coming in I give them a wide berth.

Well what do you want? A tower? A radar/control service to the ground? Stump up the cash and you can have either or both of them http://cdn.pprune.org/images/smilies/thumbs.gif
Porter I can understand your frustration and commend your vigilance and awareness when it comes to separating yourself from high performance jet aircraft at uncontrolled aerodromes.


Unfortunately, for every pilot such as yourself who is on the ball, it seems there are another two who aren't.


The reasons for this are many and varied and may include such elements such as lack of appropriate training, inexperience, deferral (that the jet can 'see' you), lack of situational awareness and even insolence.


I believe that at any aerodrome where RPT jet aircraft tangle with general aviation there should be at minimum a directed control service for at least the periods where RPT aircraft arrive and depart.


Some may point out that in other parts of the world this isn't needed.


However, I would point out that within the unique environment we operate in Australia (large distances between populous capital cities and very small, isolated and scattered regional centres) the potential for conflict with inexperienced general aviation aircraft and the once or twice a day jet RPT service is great and it's only the relatively low frequency of flights that has precluded a major disaster such as what nearly happened in this incident.


Unfortunately no money will ever be spent to improve the safety of RPT flights into aerodromes such as Mildura and we can only hope we aren't digging up threads such as this in years to come lamenting what could of saved lives.


Keep up the good work Porter, and spread the word to your fellow aviators to be vigilant in areas where they might tangle with jet RPT aircraft, tell them to keep their transponders on 'ALT' at all times, ensure that the correct frequency is selected and communicate intentions loud and clear. :ok:

Lead Balloon
17th Jan 2017, 19:56
Oh gawd. Here we go again. Unique circumstances; disaster pending.

So the pilots of XGY and XGA were "inexperienced general aviation aircraft [pilots]", were they Compylot?

What strikes me about the circumstances is the number of radio transmissions. So much talk; sooooo much talk.

Yet insufficient situational awareness.

On the part of pilots who cannot be described as "inexperienced".

Here's an idea: Let's turn aerodromes with CTAFs into Romeos for inexperienced GA pilots 30 minutes either side of the ETA of an RPT aircraft. Hmmmm, that may not work, because experienced GA pilots don't read NOTAMs, or understand them even if they do.

AFIS(Z) or CAGRO. Brilliant! Hmmmm, that may not work, because inexperienced GA pilots might not broadcast their existence or location, or might get their location wrong.

So we're back to Porter's solution: Tower, primary and secondary radar all round!

Since forever, relatively junior pilots who finally get that gig in the left hand seat of heavy metal spend their waking duty hours fretting about inexperienced GA pilots. It's an insight into their own views as to their own levels of competence 'back in the day'.

Capn Bloggs
17th Jan 2017, 22:12
Thanks for that nonsense, LB. What is your solution?

So we're back to Porter's solution: Tower, primary and secondary radar all round!
Porter's "give them a wide berth" solution has merit...

Lead Balloon
17th Jan 2017, 23:06
What is the "nonsense", Capn B?

In order to provide a rational solution to a problem, one first has to identify the problem and the causes of the problem.

The problem is the increased risk of mid-air collisions near aerodromes compared with other phases of flight.

The cause of the problem in this case was not inexperienced GA pilots. Nor was it insufficient two-way communications.

The 'solution' is to do what the rules and good airmanship have required for around 100 years.

IMNSHO, and based only the ATSB report, the pilots of XGY and XGA failed to comply with the requirements of the rules and good airmanship. Aircraft attempting a straight in approach v aircraft completing a circuit? No rocket surgery working out who was obliged to give way (a "wide berth") in that situation.

I was merely making the supplementary point that if the assumption is that GA pilots are not going to comply with the requirements of the rules and good airmanship, there is only one, inevitable, solution. Even that solution is no guarantee.

If you think about it rationally.

neville_nobody
18th Jan 2017, 01:15
The 'solution' is to do what the rules and good airmanship have required for around 100 years.

However aircraft are now being flown from head office/Canberra with such a high number of 'requirements' put on flight crew there is almost no time for 'airmanship'

In a jet you are doing 3-4 miles a minute from 20 miles, with speed restrictions, mode annunciations, CTAF Calls, stabilisation requirements, not to mention actually flying the aircraft around the circuit without stalling or overspeeding.

None of those in themselves alone are a bad thing however I think we are at the tipping point now where there is way to much input from exterior forces in actually getting the job done. The 'seen to be doing something' management culture that now pervades aviation will ultimately contribute to an accident.

This one is a classic example for the rulemaker types. Two aircraft did as they were supposed to followed all the rules yet nearly collided.

How about less rules, less 'requirements' and let pilots fly the damn thing.

ACMS
18th Jan 2017, 01:19
And now we have Drones buzzing around as well.


����

Lead Balloon
18th Jan 2017, 03:59
Two aircraft did as they were supposed to followed all the rules yet nearly collided.I don't think it is correct to say that "all the rules" were "followed" in this case (although I'm again only going on the report).

As I read it:

- ZPJ on base to 09.

- XGA conducting a straight-in to 09.

- There is a clear rule specifying who has to give way to whom in that situation.

If that rule does not apply in circumstances that led to a "near collision" between an aircraft on base and an aircraft on a straight-in, the rule is meaningless.

andrewr
18th Jan 2017, 05:30
The "near collision" seems to have happened after both aircraft went around.

ZPJ instructed XGA to go around and position to south of the airfield.
ZPJ then missed their turn to final, went around and tracked to the same place they sent XGA.

Before XGA was instructed to go around I think things were OK, they were behind ZPJ in distance to the runway and more than 500' higher when ZPJ got the traffic alert. I assume the jet approach speed is greater than the GA8 so that should work. The XGA pilot was probably of the opinion that they had given way to the traffic in the circuit.

717tech
18th Jan 2017, 06:39
An aircraft "instructing" another to do something is a bad idea.

I vaguely remember attending a CASA roadshow years ago where they played a short audio clip. It was of a Dash-8 launching out of somewhere with traffic already in the circuit or on approach. The Dash took off having never quite worked out where the traffic was and demanded the other traffic climb or turn (can't remember which). It was by shear luck that they didn't hit.

Capn Bloggs
18th Jan 2017, 07:31
An aircraft "instructing" another to do something is a bad idea.
Your example doesn't support such an idea, for a start. If you tell someone to do something, then it would be logical that you knew why you were telling them to do it because you knew where they were. There would also be many, many examples (probably more than one Dash 8 which lost/never had the plot) that CASA could blab on about where somebody doing some "instructing" made the a scenario far simpler and therefore safer for all. I had one yesterday: had we not "instructed" smasher to maintain a level, we would have to have climbed (while on approach). Not smart. As it was, it all worked out well (despite us growling at him because we saw on the TCAS that he didn't level off! :)).

There are plenty of scenarios where it is advantageous to "take control" and ask for a level-off or maintain a track. Lud Slud and Dick et al hate being told what to do, but I've made more concessions to lighties than have been made to me. Why do you think ATC exists?

Apart from why the cowboy approach by the lighty from the west, the important question is... why was the EJet captain "preoccupied with PF duties and did not comprehend all the radio broadcasts." He/She was the most important (experienced/skilled) part of the whole thing. He/She has to be on top of what is going on.

Utradar
18th Jan 2017, 09:22
You guys are off the mark. 'Instructing' the aircraft concerned was a desperate measure to avoid a collision so 'instructing' to avoid a collision is the best course of action at the time.

Bloggs, the GA aircraft made the first broadcast at 11,000' at 10nm probably while the jet joined xwind, flaps were running and operational talk existed. The ATSB said that both aircraft made all the required calls, however the radio call to conduct a straight in approach by XGA actually happened at the end of the exchange with other traffic at 7nm and with no other call after that.

A jet is configuring in the circuit at that time getting set up for landing, not twiddling thumbs listening for conflicting traffic (that's not expected). The mental traffic model has already been created earlier. If the jet guys are configuring, setting flap, operational conversation and miss a call that has not been expected earlier, then you can assume problems. In a high workload environment, the first to go is your hearing, just providing balance to your comment.

Brakerider
18th Jan 2017, 09:32
I would normally advise against QLink style 'Instruction' over the radio, eg- Do this so we can take a 10 knot tailwind and save 30 seconds. However, in some cases it is certainly required. By no fault of their own, some smaller aircraft pilots do not have the proper appreciation of Jet/Turboprop operations let alone a 'commercial operation'. I find often the safer option is to slow it up and let the 172 finish his circuit rather than direct him to remain upwind or extend downwind, but I appreciate this isn't always the easiest thing to do with commercial pressure coupled with the speed of a Jet or Q400.

Lead Balloon
18th Jan 2017, 09:50
I thought I'd read it all on PPRuNe Downunda, and then someone comes along with a reference to "instructions" from one aircraft to another.

I know what my response to an "instruction" from another aircraft would be.

(Thanks for your post AndrewR. I think I need to read the report more closely. If what happened was as you described, it kinda puts a different slant on things.)

Capn Bloggs
18th Jan 2017, 10:20
You don't understand what we're talking about, do you LB?

Lead Balloon
18th Jan 2017, 10:42
Clearly not. I've been labouring under the misconception that I knew what the terms "instruction" and "take control" meant.

Good luck with your amateur ATCing! The odds are always in your favour. :ok:

Compylot
18th Jan 2017, 11:43
As I mentioned earlier, 'insolence' could be one contributing factor to the lack of appropriate, professional interaction exhibited by a small minority of GA pilots when operating in CTAFs.


I am sure that Lead Balloon enjoys a faux aura of expertise while discussing piston engine operating principles and airmanship at the local aero club whilst jabbing his wine glass in animated excitement, splashing it's contents on those around him as they once again roll their eyes.

Capn Bloggs
18th Jan 2017, 12:22
Good luck with your amateur ATCing!
Arrh, the irony. Instead of luck determining whether I clobber a lighty or just scare the hell out of either or both of us, with mutually arranged "instructions" we both happily miss by a mile, with minimal (mutual) inconvenience, and go on our merry way.

Lead Balloon
18th Jan 2017, 20:02
As you seem to be able to have a rational discussion without switching to skygod mode, andrewr, I'd be interested in your perspective on this from the report: ZPJ joined the Mildura Airport circuit on the crosswind leg for a left visual circuit to land on runway 09.

On the base leg of the circuit, the flight crew on board ZPJ heard their traffic collision alert system (TCAS) announce a traffic advisory (TA) aural alert (see TCAS limitations on approach). They glanced at their TCAS display to check the relative position of the traffic, which indicated it was to their right (position 1 in Figure 1). The flight crew looked out the right window of the flight deck and identified the traffic to their right and high against the skyline. The traffic appeared to them to be stationary in the windscreen relative to their own aircraft and with a high closure rate (from TCAS data the aircraft were 1.25 NM apart at the time of the TA alert).I interpret that to mean that while ZPJ was on base, XGA was on final from a straight in approach. The fact that XGA appeared stationary to the crew suggests to me that the aircraft were on relative tracks that were highly likely to intersect at the same time in the same place. (I came to these conclusions while sloshing wine at the local aero club....)

You said:Before XGA was instructed to go around I think things were OK, they were behind ZPJ in distance to the runway and more than 500' higher when ZPJ got the traffic alert. I assume the jet approach speed is greater than the GA8 so that should work. The XGA pilot was probably of the opinion that they had given way to the traffic in the circuit.Is that based on any 'inside knowledge'?

If XGA appeared stationary in ZPJ's cockpit, ZPJ would have appeared stationary in XGA's cockpit, thus raising the question whether the pilot of XGA's opinion was correct (even assuming XGA saw ZPJ and had that opinion).

Why do you think they were "OK" in that circumstance?

(And Compylot and Bloggs: Clearly we operate in vastly different places, because I've never heard or had any 'insolent' interaction on any CTAF, or heard any benevolent skygod give 'mutally agreed instructions' or 'take control' in any CTAF. But maybe I just insolently leave my VHF switched off....

My only advice to you is when you switch to amateur ATC mode, ya better get it right. As I observed before, the good news for you is that the odds are vastly in favour of not having a collision, even before you open your mouth.)

andrewr
19th Jan 2017, 07:20
Is that based on any 'inside knowledge'?

Just based on the information in the report. Figure 1 on p 2 and figure 2 on p 4 show the relative locations of the aircraft. Eyeballing each point it looks like XGA was behind.

Table 2 gives the altitudes, Time 3 was the TA with ZPJ at 733' on base, XGA at 1300' on a 3.5 miles final. I don't know the exact approach speeds, but I would guess that from 3.5 miles XGA could slow down enough to give e.g. 60 seconds spacing at touchdown.

However, with a closer look at the figures something looks sus. The positions were taken from ZPJ TCAS I think. They have XGA doing 2.4 miles in 43 seconds, or about 200 knots - in a GA8? I'm not sure how accurate those positions really are.

If XGA appeared stationary in ZPJ's cockpit, ZPJ would have appeared stationary in XGA's cockpit, thus raising the question whether the pilot of XGA's opinion was correct (even assuming XGA saw ZPJ and had that opinion).
Why do you think they were "OK" in that circumstance?

On a collision course they appear stationary right up to impact. However, the further away you are the smaller the angle of any movement, so depending on distance the movement might be hard to detect. I don't know how long they spent working out whether XGA appeared stationary.

Also they were about to turn final, so if they were on a collision course before changing direction, pretty much by definition they would not be once they turned final (as long as they didn't collide on base, obviously.)

Lead Balloon
19th Jan 2017, 09:18
Thanks AR

Very interesting.

It would be ironic if the "instruction" turned a benign situation into a close call. (I've been surprised sometimes when ATC has told heavy metal that they might get a TCAS RA from me, even though they are what seems to me to be a looooong way away. e.g. me late downwind and the heavy metal on long final. Someone very close to me who flies heavy metal says the SOP is to disable functions of the TCAS when operating into various busy airports OS, due to the volume of nearby traffic. But maybe I misunderstood the detail.)

Serious question for the heavy metal drivers: So you're on base at YMIA and a GA guy doing a straight in approach to the same runway is a collision risk but isn't on frequency or ignores the "instruction". What's the plan? I assume that because this is an obvious risk (or is it "threat" these days?) there's a pre-briefed plan.

(I know what you're likely to after you land, but what's the in-air plan?)

Compylot
19th Jan 2017, 11:57
Someone very close to me who flies heavy metal says the SOP is to disable functions of the TCAS when operating into various busy airports OS, due to the volume of nearby traffic. But maybe I misunderstood the detail.)
Spot on Leadie (do you mind if I call you that?)


The TCAS has many modes, "The Overseas Busy Airport Function, or OBAF, The Sydney Airport Parallel Runway Operation Mode, or SAPROM and even the Remote Area CTAF Function, or RACF, although I believe that this is an option that only Australian operators can purchase.


If you'd taken the time to Google this then you wouldn't be wasting our time here!


As for Serious question for the heavy metal drivers: So you're on base at YMIA and a GA guy doing a straight in approach to the same runway is a collision risk but isn't on frequency or ignores the "instruction". What's the plan? I assume that because this is an obvious risk (or is it "threat" these days?) there's a pre-briefed plan.
As a Sky God I would just continue because my heavy metal is bigger and would just end up pushing the lighter metal aircraft out of the way.


Hopefully we'd all end up alright, I mean there might be a few dents here and there but nothing too serious :ok:

(..and how "Someone very close to me who flies heavy metal" are we talking here? Like 'wink wink' close or 'claws in the air, rooaaar go you good thing' close?)

Biatch
19th Jan 2017, 12:51
The threat of traffic in an OCTA airfield would be briefed in the approach briefing during cruise. However a specific "plan" wouldn't exactly be detailed as the exact circumstances and relative positions aren't known would require differing actions. Generally should such traffic as you describe be encountered the plan would generally be see and avoid, separate ourselves vertically as well as horizontally, wait for said traffic to become clear (land or exit the circuit etc) and then proceed.

It is not a recommended practice to disable in anyway the TCAS functions for anything other than an engine failure where it is directed by the checklist due to the lack of performance requirements to comply with possible instructions, thus forcing another TCAS aircraft to comply with a resolution. I can't speak for ops overseas, but in Aus, it is not practice to turn off TCAS in anyway... what's the point in having it then?!?

Typically the thing that make things hard is a/c not making calls due to lower requirements these days and also perceived lack of need by the GA/smaller aircraft. Typically jets are doing 250knots from 30nm out which means they will enter the circuit (at approx 200knts) in around 7-9mins from that point. Things happen pretty quick and wider berths than expected are preferred as a result. We also want to prevent TCAS events (paperwork!) which are time based and whilst we know the parameters of such events, we don't see the exact real time limits/points that these will trigger.

The working environment is pretty busy as soon as you get a couple aircraft in the area. Crew co-ordination, configuration, ATC running on another radio at the same time giving traffic info, all the while trying to separate yourself from other aircraft. Add to this traffic magically appearing at 5nm-10nm without so much as a position report or response and it gets intense quickly. This has happened to me multiple times for varying reasons...

Earlier it was said that they "instructed" the go around as a last ditch effort, esp seeing as from their point of view (and my interpretation of the regs) they had right of way. This sounds about right and simply an extreme example. Typically anything we ask of another aircraft whilst trying to separate is a request more than an "instruction". Eg "if you could remain north of centreline until we depart south" is just us simply trying to ensure some sort of separation. It's hardly "ametuer atc".... it's professional pilots trying to ensure the safety of their aircraft with other pilots who may or may not be cognizant of our spacing requirements. Of course no aircraft is required to comply with any "request" and thats fine, we don't expect you to if you have right of way, so we'll typically just wait.

For the most part, despite my few bad experiences, usually GA/slower aircraft are more than helpful and usually more than willing to slow up/be # 2/give way etc etc and even usually offer it without us even requesting. I can tell you it's greatly appreciated and an absolute pleasure to share the airspace with you guys. I also understand that there are some situations which can be a pain for them and some of our guys push the friendship with straight in's onto rwy's with tailwind when other aircraft are using the reciprocal. I can't speak for all but personally will only try said jazz when it doesn't conflict with any known traffic in the area that has right of way.

Biatch
19th Jan 2017, 13:40
I'd also like to add that the CTAF freq at Mildura is shared with two other close by aerodromes. I can't tell you the number of times coming into Mildura that a lot of the CTAF calls are garbled by multiple aircraft at multiple aerodromes making calls. It's a joke and the y shouldn't be using the same freq...and in my opinion could have likely played a part in this conflict.

Lead Balloon
19th Jan 2017, 19:38
Thanks for all of that, Biatch. My long experience is also that GA/slower aircraft are more than willing to volunteer to adjust their track and circuit join to give RPT, RFDS etc aircraft priority. I've literally never heard any terse or insolent exchanges between the former and the latter.

I understand what you're saying about not having a specific plan.

So I'll change my question to: You're on base at YMIA and there's an aircraft on a straight in approach to the same runway. You assess there to be a high risk of collision. The aircraft is not responding to any calls from you. What do you do?

I'm assuming that compylot's decision to collide is the result of a lack of skill and experience (or is perhaps an insolent and immature response). I'd like to hear from someone who knows what s/he's doing, as my loved ones could be seated down the back.

Biatch
20th Jan 2017, 01:14
I think sarcasm is at play there mate... poorly executed... but hey, it's pprune!!

To answer your specific scenario ... hoping (and assuming) that we had said aircraft in sight to our right... personally I would make a clearing and climbing turn away from the aircraft on the straight in approach. That would be a left turn towards upwind. Which is exactly what the skipper had elected to do.

Now the final report mentions the PM advised of further conflicting traffic crosswind. So the PF then elected to a go around toward the south of the centreline but parallel to the rwy. Fair enough, and the best of a bad situation, just that the XGA A/C had assumed that the jet would be continuing their approach and not going around due to their approach not meeting stabilisation criteria. And this is as I read it, where the worst of the conflict occurred. Probably not enough time in the seconds that this decision was made to communicate it effectively, and thankfully the pilot of XGA recognised this and was able to see and avoid. This is exactly the reason why we generally need or want a larger buffer/space around us than what smaller aircraft are used to or may expect.

Hate to armchair quarterback it, but seeing as you asked my opinion, I may have elected to climb to a height above circuit/MSA as well. May or may not have helped or been necessary... but looking back on it with hindsight, it might have been something entering my plan of evasion... and now that I've thought about it more for another min or two while writing this, the skipper may not have wanted to do that as XGA was above him already and a rapid climb may have seemed to make it worse. It's just so hard to tell without actually being there....

You can see how the situation became very intense very quickly with only 2 other aircraft in the circuit/area. (the third chasing aircraft wasn't really involved in the conflict, although it also broke off approach to the south.) Jets aren't really made to share a circuit with GA aircraft. Lots of guys prefer 5nm straight approaches, even with tailwind, to avoiding doing circuits with other aircraft.

The name is Porter
20th Jan 2017, 01:53
Your post shows that you're completely unaware at the workload of flying a jet in a circuit and the encounters that jet pilots have with unbroadcast traffic which I would say is kinda risky, wouldn't you?

Dood, I'm fully aware of your workload, really. I've been around a bit.

Whenever I've flown into one of these aerodromes if I hear a turboprop/jet coming in. 'You go first mate, I'll hang out here' it's no issue. I've had the odd turbo say, 'no worries, you go first, we'll slow up' :eek:

Comes down to a bit of courtesy, airmanship and education.

On eyre
20th Jan 2017, 04:19
As a VFR charter operator I am more than willing to slow down/adjust runway etc to go No. 2 to an inbound RPT that has advised the same ETA. I do get rightly pissed off however, after offering this to have said RPT actually hit the circuit several minutes after the advised ETA. Particularly when I have slowed down considerably to accomodate them - could have landed, unloaded pax and had aircraft in hangar and doors closed. Might not be so helpful next time.

Lead Balloon
20th Jan 2017, 08:36
Thanks again, Biatch.

The intriguing question is: Would there have been a lower risk of collision if ZPJ had just commenced a climb from base as soon as the risk of collision with XGA was perceived, and XGA had just continued its approach? (That's why I provided a scenario in which the equivalent of XGA pressed on, regardless.)

If I'd been XGA I think I would have just called 'going around and tracking parallel 09 to the south' as soon as I realised there was an aircraft on base, set full power and climbed at best rate and tracked slightly to the south of runway 09. In the circumstances as described in the report, I don't see how that would have resulted in any greater risk of collision than what actually happened. ZPJ has me in sight, and knows where I'm going. I have ZPJ in sight and can watch and listen where he decides to go. We both know about the other traffic.

However, as you say this is just Monday morning quarterbacking. Much rather someone else than me in these situations.

Utradar
20th Jan 2017, 10:11
LB if you've seen the movie 'Sully' you'll know there's an amount of time called the 'human factor'. Hindsight is always 20-20.

More complex issues exist here. The ATSB calls for an Alerted search that uses radio and TCAS to know where to look. What defences exist when this fails? Both have limitations. Radio - eg (wrong frequency, turned down, wrong location where broadcast), different airports - same frequency. TCAS - delays in updating during turns, other aircraft not having transponders on or not equipped.
The ATSB has not delved into these more complex issues.

Lead Balloon
20th Jan 2017, 20:54
Hi U

Good points.

However, I think all those more complex issues are trite. That is, they are all well known.

Every now and then, lots of the holes in the pieces of Swiss cheese are going to line up. Fortunately, the chances of them all lining up are extraordinarily remote and, as in this case, no collision occurred. Whether that outcome in this case was a matter of good luck rather than good management is, I reckon, moot. We don't know whether decisions and actions other than those that were made and implemented would have resulted in the aircraft remaining further apart than they ended up being.

That doesn't mean that nothing should be done to mitigate even those risks. However, when you think through what the mitigation options would be, and how much they would cost, and that they would still be no guarantee of collision risk-free skies, you get back to reiterating the basic requirements of the rules and airmanship that have been around for around 100 years. ('Affordable safety' is a fact of everyday life, not a radical theory. That's why not all roads are divided, there aren't traffic lights at every intersection and there's only a millimetre of insulation between you and a voltage that will kill you.) It may get to the point that the volumes of traffic at YMIA are such as to justify further mitigations - CAGRO, Class D, revival of the AFIZ concept - but they are no guarantee.

I'd be interested in others' views on whether my decision - if I were in XGA - to go around and track to parallel runway 09 to the south as soon I became aware of the aircraft on base, and announce that on CTAF - is a good one or a not-so-good one. (I fly into and out of YMIA occasionally.)

Capn Bloggs
20th Jan 2017, 23:09
ATC running on another radio at the same time giving traffic info
This is neither necessary nor a good idea. Call "changing to CTAF...", turn down the ATC volume (but not off) and then you can concentrate on the CTAF. The only possible traffic that ATC would pass to you after you have changed would be traffic that commences taxi... which you will: 1/hear on the CTAF and 2/hear on the FIA freq when he makes his taxi call. Perhaps a "popup" or traffic alert might prompt ATC to call you in the blind, but vary rarely.

Perhaps there was some yabbering on Centre that distracted the Ejet captain so that he couldn't comprehend or hear XGA.

It would have been nice to read the radio transcripts of the CTAF...

andrewr
21st Jan 2017, 02:14
Did the incident really happen?

According to the tracks shown in the report, the GA-8 was going faster than the ERJ190. It averaged 200 knots for a period of 43 seconds. At one point it travelled 1 mile in 15 seconds i.e. 240 knots.

Is this plausible?

The majority of the report seems to have been compiled from the ERJ TCAS data during it's turn from base to final/upwind. What if the turn made the TCAS data inaccurate? When the ERJ straightens out on upwind, the GA-8 track shows a very sudden turn to the south. Could that have been the TCAS correcting the calculated position, once it had a stable reference?

If you use a more likely 120 knots for the GA-8, the closest point of approach is more like 1 mile, instead of 0.1 mile.

The GA-8 was behind the ERJ, so the ERJ wouldn't be able to visually confirm the distance. It is interesting that there is little information from the GA-8 pilot's point of view, other than confirming they sighted the jet about 2 miles away after the radio call. He should have been able to see the whole situation immediately in front of him.

Maybe they looked at the TCAS and asked the pilot if he saw the jet 200 metres in front of him and he said "There was no jet 200m in front" so they wrote a report about the difficulties of see and avoid, instead of investigating whether the GA-8 was actually where the TCAS said it was.

On the balance of probabilities between a GA-8 doing 200 knots almost running up the back of an ERJ 190, and inaccurate TCAS data during the turn, my money would be on the inaccurate TCAS data.

It would be interesting to see actual tracks from both aircraft's GPS instead of the tracks derived from TCAS.

BPA
21st Jan 2017, 02:56
By bet is XGA spent most of time talking to XGY on company frequency ie distracted and that's why they never heard any calls from ZPJ. What frequencies was the pilot of XGY monitoring. Was XGY on CTAF, did they here ZPJ?
What about the other twin in the circuit and the other RPT traffic from the north, what calls did they hear from ZPJ and XGA?

Snakecharma
21st Jan 2017, 03:17
Andrew, how fast does an airvan go? The ejet would have been gear down flap 3 or at least have some flap out so speeds around 160 ish I would hazard a guess

Lead Balloon
21st Jan 2017, 03:25
It is a bit weird, andrewr.XGA, with XGY in-trail, was about 7 NM from Mildura Airport tracking to the north-east to intercept a 5 NM final position, at 140–150 kt airspeed, descending at about 2,000 ft per minute.How steep would the descent have to be to get to 200 - 240kts GS?

According to Table 2, it took ZPJ 15 seconds to go from point 2 to point 3, and 28 seconds to go from point 3 to point 4.

And according to the report, the "TCAS data is indicative only"....

Biatch
21st Jan 2017, 04:42
This is neither necessary nor a good idea. Call "changing to CTAF...", turn down the ATC volume (but not off) and then you can concentrate on the CTAF. The only possible traffic that ATC would pass to you after you have changed would be traffic that commences taxi... which you will: 1/hear on the CTAF and 2/hear on the FIA freq when he makes his taxi call. Perhaps a "popup" or traffic alert might prompt ATC to call you in the blind, but vary rarely.

I take and understand your point ... and even to a degree agree with it, however it is a "must" in the manuals for this company involved.

Without knowing the driving force behind the "must", I would be hesitant to out of hand write it off as not necessary or less safe or the like. I would guess that the benefit of ATC providing traffic of aircraft in the area out ways the threat of having two radios running, esp when if it is a bit much a pilot can just turn it down a tad as you pointed out.

I wouldn't also presume to be able to think of all the possibilities or scenarios where ATC may still be able to provide critical information. Especially as in my opinion the reporting/broadcast requirements are so much lower these days. Terms like "vicinity" are useless in the regs, and whilst a 10nm call inbound for a small GA aircraft is commensurate with its performance, high performance aircraft would still like to hear from it before 10nm.

Capn Bloggs
21st Jan 2017, 05:33
I wouldn't also presume to be able to think of all the possibilities or scenarios where ATC may still be able to provide critical information.
There aren't many. Said company should reconsider mandatory operation on two different freqs.

Terms like "vicinity" are useless in the regs, and whilst a 10nm call inbound for a small GA aircraft is commensurate with its performance, high performance aircraft would still like to hear from it before 10nm.
Wholeheartedly agree, and we all know who is responsible: Dick Smith and his yank NAS.

Lead Balloon
21st Jan 2017, 05:50
You should arrange to give some "mutually-agreed instructions" to Biatch's employer and all GA aircraft, Capn.

The irony is that XGA may not have been the aircraft that got closest to ZPJ during that flight.

Capn Bloggs
21st Jan 2017, 06:02
More potshots from the peanut gallery LB... :rolleyes:

esp when if it is a bit much a pilot can just turn it down a tad as you pointed out.
Sorry, I sped-read your previous post and didn't absorb this bit. If you haven't "changed to..." ATC will keep calling you until you reply; it doesn't matter that you have the radio "turned down a tad" resulting in more workload on the ATC freq when you should be dealing with the CTAF traffic.

Biatch
21st Jan 2017, 07:12
There aren't many. Said company should reconsider mandatory operation on two different freqs.


The risk analysis of the "few" that you can think of may still warrant it.... And in my opinion the few that no one can think off may also warrant it...

Off the top of my head, and this has happened to me. Traffic at 20nm thinking he is not traffic, not broadcasting or possibly listening on ctaf, but thankfully squawking 1200. Our TCAS had not picked him up due to whatever reason (it's not perfect and has its blind spots/flaws) but ATC chimed him and gave him as unidentified traffic intentions Unknown.... We were able to level off 2000ft above, TCAS then picked him up... And we proceeded after passing. Never made contact.

This large associated risk of this situation, though it may happen rarely, may (in the company's view) warrant the possible threat of having two Comms on.

It seems that REX does have the policy of going off act, as I hear them making the call you're referring to. I can't remember Qlink's policy.

Wholeheartedly agree, and we all know who is responsible: Dick Smith and his yank NAS.

Yep

The name is Porter
21st Jan 2017, 22:57
Having flown quite a bit in the US where the traffic densities shit all over the GAFA, they seem to be doing something right. Australian airspace is over regulated and full of arse guarding useless information masquerading as 'service'

I would take their system over the Australian system any day of the week.

gerry111
22nd Jan 2017, 08:18
Compylot commented on Lead Balloon's comment: "Someone very close to me who flies heavy metal.."

I know one of LB's younger siblings who's an experienced B777 Captain for an overseas airline.

LeadSled
24th Jan 2017, 06:49
This is neither necessary nor a good idea. Call "changing to CTAF...", turn down the ATC volume (but not off) and then you can concentrate on the CTAF.O.M.G.!!
What is the world coming too??? This is at least the second time in recent memory I have agreed with Bloggs.
As to the point of the thread, clearly nothing has changed since the PCH ( or was that PHC) report, and the entitlement assumption by Regionals is a strong as ever, as is the assumption that anybody flying a GA aircraft is automatically of lesser qualifications and experience.
As for the "standard" of the ATSB effort, why am I not surprised.
Tootle

bolthead
24th Jan 2017, 11:13
If I'm understanding the numbers correctly, that was one highly ambitious approach by XGA - even disregarding there were 3 other aircraft inbound. Even leaving its turboprop big brother in its wake.
Can't help but think there is a fair bit more to the story, leaving one to speculate. Busting for a leak? See if the old girl can still handle Vne? What's that funny smell? Burning?

Lead Balloon
24th Jan 2017, 19:41
You're understanding the numbers correctly, but the numbers cannot be relied upon as accurate. Key position data is derived from TCAS and, as the report itself states, that data is "indicative only".

I'm convinced andrewr has it right. The indicative numbers don't add up.

A relatively benign situation may have resulted in the two aircraft ending up much closer than they would otherwise have been, as a consequence of a natural response to the TA and an aircraft out the window when feeling the cold chill of exposure in Class G airspace. But I acknowledge this is merely Monday morning quarterbacking.

andrewr
25th Jan 2017, 01:22
The TCAS data suggests he was doing 140-150 knots on descent from 10000', then accelerated to around 200 knots on 4.5 mile final. A search for GA-8 VNE suggests it is 185 kt.

The distances are short enough that an error of 1/2 mile one way at the beginning and 1/2 mile the other at the end brings the required speed down to a more plausible 120kt. But if you need a margin of error to make it fit, assuming accuracy in rest of the analysis doesn't make sense.

I found this interesting link about TCAS accuracy in turns:
http://www.tc.faa.gov/its/worldpac/techrpt/tctn099.pdf

I don't know how relevant it is to current systems. But the entire "near miss" occurred while the jet was turning. Before the turn, XGA was slightly behind and around 700 feet higher. When the jet straightens on upwind, XGA suddenly appears south of the airfield (where he said he was going to go when asked to go around)

During the turn, TCAS says he was doing 200 knots and almost ran into the back of the jet (0.1 mile separation). It makes a lot more sense if the TCAS data is unreliable in the turn.

ANCIENT
28th Jan 2017, 03:35
andrewr I think you need to to read up on how TCAS works. The only thing that is accurate about TCAS is the altitude. Both bearing and distance are best guess worked out by an algorithm using a few assumptions on the signal strength. Generally accurate enough to visually identify the target, however I have experienced seeing a TCAS target to the left of my flight path when in fact we had visual contact with the aircraft and it was to our right. Too many pilots put too much faith in the bearing and distance of a TCAS target. Also seen target jumping around as system tried to work out the correct bearing in relation to us.

Lead Balloon
28th Jan 2017, 07:07
Perhaps the ATSB needs to read up on how TCAS works, before using the phrase "traffic conflict" to describe what happened.

A TA is not a traffic conflict.

A situation in which one aircraft is obliged to give way to another is not a traffic conflict.

Capn Bloggs
28th Jan 2017, 08:16
Rubbish LB, nobody was giving way to anybody until well after the TCAS TA. The fact they ended up so close is testament to the seriousness of the situation. This is RPT jet stuff here, not 150 vs PA28. Things should not get anywhere near this close.

Lead Balloon
28th Jan 2017, 08:32
First, Capn, you don't know how close they ended up. As the report says, the TCAS derived data is merely "indicative" - a word that means ... what, precisely?

Secondly, you don't know whether the aircraft would have ended up 'less close' if the jet had merely continued its approach and XGA had been left to give way once XGA was alerted to the jet's position on base. The actual response may have made things 'worse'.

You say that "things should not get anywhere near this close". What is the minimum distance you apply when engaging in amateur ATC?

andrewr
30th Jan 2017, 00:40
andrewr I think you need to to read up on how TCAS works. The only thing that is accurate about TCAS is the altitude. Both bearing and distance are best guess worked out by an algorithm using a few assumptions on the signal strength.

Actually that is my point. The report relies heavily (exclusively?) on the TCAS data. As far as I can tell it is only the TCAS data that indicates that the "near collision" even happened - there is no visual confirmation mentioned in the report.

If you think incorrect TCAS data is more likely than a GA-8 doing 200 knots and overtaking a jet, it also seems likely that there was no near collision.

If you use more likely speeds for the GA-8, it was probably never closer than a mile to the jet, with the gap increasing.

Compylot
30th Jan 2017, 11:38
I think I get in now Leadsie (do you mind if I call you that?).


From your language ("heavy metal" "Amateur ATC" and "I know what my response to an "instruction" from another aircraft would be.") it is clear that you have a chip on your shoulder when it comes to operating at the same time as RPT aircraft.


Look, I get that you may be a moderately experienced GA pilot who's brother is a professional pilot, yet we don't know when communicating on CTAFs who we are operating with. Whether that voice is a student on a first solo nav, a crusty old crop duster or a private pilot on their once a month flight, it can be hard to ascertain.



Hi U

Good points.

However, I think all those more complex issues are trite. That is, they are all well known.

Tell me, what more 'complex' issues are 'trite'?



You may be awesome and have exceptional situational awareness, but that doesn't mean everyone does.


So don't take it to heart if you've experienced 'amateur ATC', I'm sure that wasn't the intention. You may of been communicating with a crew who were tired after multiple sectors operating into a high workload environment in a high performance aircraft.

Tell me, do you operate an aircraft that has TCAS?


Perhaps lighten your grip on that yoke, stop sweating and mumbling curse words over 'heavy metal drivers' and realize that we all just want the best and easiest outcome.


You keep wanting clarification on 'what could I have done to mitigate such an incident happening' yet I get the impression that you are dipping your toe here in the big pool not to learn, but rather to validate your own opinions.


As I have said before, when in a CTAF, ensure your transponder is on ALT, ensure you have the correct frequency selected (listen for the beep back) and make clear and concise radio calls stating your position and intentions.



If you're 'asked' to clarify something, or your altitude or position once again when you thought you'd just given it, don't take it to heart.


Smile and enjoy the view, you're lucky you get to fly as much as you do :ok:

Utradar
30th Jan 2017, 12:21
From the report:

'The flight crew looked out the right window of the flight deck and identified the traffic to their right and high against the skyline. The traffic appeared to them to be stationary in the windscreen relative to their own aircraft and with a high closure rate (from TCAS data the aircraft were 1.25 NM apart at the time of the TA alert)'

So the report does mention a visual confirmation.

Lead Balloon
30th Jan 2017, 19:56
You evidently have a written comprehension problem, compylot. I have stated, repeatedly in this thread, that I have never had or heard any insolent interactions on a CTAF with any other aircraft - RPT or otherwise. That includes at YMIA.

I suspect that wherever you and the Capn operate, the insolent conversations may be precipitated by arrogant RPT pilots who presume to engage in amateur ATC on the basis that they "know better". For that is what it is, pure and simple: amateur ATC. And as I've also said in this thread, my only advice is that ya better get it right.

In the case of the event that led to the discussion in this thread, the amateur ATC may have made things worse. I know you can't bring yourself to concede that, but that just shows you're incapable of being objective.

Utrader seems to have a comprehension problem, too. (Are you people really in charge of aircraft full of passengers?) Who suggested a "conspiracy"? Who said there was nothing in the report about the jet seeing XGA?

Please read what andrewr has posted. Twice.

Utradar
30th Jan 2017, 23:18
Actually that is my point. The report relies heavily (exclusively?) on the TCAS data. As far as I can tell it is only the TCAS data that indicates that the "near collision" even happened - there is no visual confirmation mentioned in the report.

Not having a go at you LB, just relax and play nice.

I was just pointing out the report shows the pilots of the jet did see the conflicting aircraft and TCAS assisted in providing altitude information. It was shown to pass 200' above ZPJ. Let's not downplay the seriousness of this.

arrogant RPT pilots who presume to engage in amateur ATC on the basis that they "know better"

And is exactly why something needs to change operating to these aerodromes. The mix of aircraft is too complex at airports like Mildura. Basically jets can't manoeuvre to avoid collisions at close range due to energy state and cause a lot of wake turbulence along with other considerations.

There's difference in airmanship and professionalism between RPT pilots and 'casual' pilots. It's usually ends up being the casual pilots who make it difficult for the RPT guys due to lack of skill, awareness, experience etc. That's why the initiative of separation by radio usually comes from the RPT pilots.

In the case of the event that led to the discussion in this thread, the amateur ATC may have made things worse

LB there was no 'amateur ATC'. Communication was made with XGA to alter course to avoid collision in the heat of moment. This is hardly 'amateur ATC'.

Capn Bloggs
30th Jan 2017, 23:53
"Arrogant", "Insolent", "Amateur", "Know Better". Appears to sum up LB nicely.

And is exactly why something needs to change operating to these aerodromes.
As Porter (I think it was) does: everybody clear off until RPT on the ground. That would solve LB's "suspected" problem that "May" or may not be a problem.

Lead Balloon
31st Jan 2017, 02:34
LB there was no 'amateur ATC'. Communication was made with XGA to alter course to avoid collision in the heat of moment. This is hardly 'amateur ATC'.The assertion that XGA's alteration of course was necessary to avoid a collision merely begs the question. That is, it merely assumes that which is to be proved.

Do you entertain the possibility - just the possibility - that the outcome was worse than if each aircraft had continued its approach?

If you read back through this thread, I was initially convinced that collision avoidance action was necessary. I then read the report, twice, and read andrewr's input, thrice, and am no longer convinced.

I am happy to stand corrected, but only on words out of the mouth of the pilot of XGA.

I call that being objective.

I've flown more approaches in my aircraft than the pilot of ZPJ has flown in the type that ZPJ is. Who you you reckon is better able to judge where my aircraft is going to go, how long it will take to get there, how slow it can fly and how quickly it can climb, on approach? The pilot sitting in ZPJ or me sitting in my aircraft on approach?

Who do reckon spends more time 'close' to other aircraft and manoeuvring to avoid collisions?

I do understand the principle and benefits of mutually agreed separation arrangements. I enter them quite frequently. I'm merely pointing out that the person in seat 0A of a jet is not necessarily best qualified to 'take the lead' or - shall we say - 'be assertive' as to what those arrangements should be. The fact that a sentence starts with: "I have 81 pax down the back" does not turn whatever operational 'suggestion' the sentence ends with into an objective truth. Just imagine if ZPJ and XGA had collided on the go around, and the last conversation on ZPJ's CVR was XGA agreeing, at ZPJ's 'suggestion', to break off the approach and head towards the point at which the aircraft subsequently collided.

When I read proposals like Capn's "everybody clear off until RPT on the ground" and statements like "the mix of aircraft is too complex at airports like Mildura", I just laugh. Not through disrespect - and I mean that seriously - but rather at how people would cope at first world aviation nation traffic densities.

Utradar
31st Jan 2017, 04:03
Do you entertain the possibility - just the possibility - that the outcome was worse than if each aircraft had continued its approach

Whatever, thats irrelevant now. You're judging based on events that happened in the 'heat of battle'. What is important is the question; what CASA is going to do about it? There was an incident where primary radio alerted search failed. What defences do we have when this happens and is it good enough taking into account the complex environment for a jet?

It's obvious the pilots of both aircraft didn't know each other were there until the pilots of ZPJ saw the Airvan during base turn. What would you have said LB? "AIRCRAFT ON FINAL LOOK OUT WE'RE ON A COLLISION COURSE!" or would you have said nothing and continued the approach?

I've flown more approaches in my aircraft than the pilot of ZPJ has flown in the type that ZPJ is. Who you you reckon is better able to judge where my aircraft is going to go, how long it will take to get there, how slow it can fly and how quickly it can climb, on approach? The pilot sitting in ZPJ or me sitting in my aircraft on approach?

Who cares?

What matters is the positive outcomes, hopefully a review within CASA of the limitations of see and avoid and alerted search at non-controlled AD's.

"I have 81 pax down the back" does not turn whatever operational 'suggestion' the sentence ends with into an objective truth

What are you on about? It's called positive airmanship. Either pilot can do it, it just so happened that ZPJ saw the conflicting aircraft (XGA) first.

Remember hindsight is always 20/20.

Capn Bloggs
31st Jan 2017, 04:06
Precisely the arrogance that I was alluding to before. You really are a special, LB. You may be an ace in your bugsmasher; the fact is that not only do you not have a clue about operating a jet in a CTAF, it is painfully obvious you don't want to know.

You are so blinkered that you can't even see the sarcasm in my suggestion that everybody rack off when I'm about.

There are none so blind as though who will not see.

andrewr
31st Jan 2017, 08:46
'The flight crew looked out the right window of the flight deck and identified the traffic to their right and high against the skyline. The traffic appeared to them to be stationary in the windscreen relative to their own aircraft and with a high closure rate (from TCAS data the aircraft were 1.25 NM apart at the time of the TA alert)'
So the report does mention a visual confirmation.

At this point the TCAS showed the GA-8 as doing 240 knots, so I think the position data is suspect. The GA-8 pilot estimated the distance as 2 miles. If you use a more reasonable 120 kt for the GA-8 it adds 1/2 a mile i.e. 1.75 miles.

The GA-8 was also 500-600 feet higher. 2 miles and 500 feet doesn't seem like something to worry about with visual separation.

It was shown to pass 200' above ZPJ

This is where there is no visual confirmation. This was 40 seconds later, the jet has turned 90 degrees, and the GA-8 has somehow averaged 200 knots to get to this position. I'm sure the altitude is right, but it seems more likely that XGA was still at least a couple of miles away horizontally.

Capn Bloggs
31st Jan 2017, 09:21
2 miles and 500 feet doesn't seem like something to worry about with visual separation.

Are you serious? They are on a collision course!

Utradar
31st Jan 2017, 09:27
Andrewr,

Without radar, it's a bit tricky to assess the exact distance between the two aircraft but i've heard the E190 QAR is very good but even if there's errors with the TCAS you're overlooking that a potential collision was imminent if the crew were not alerted by TCAS and the aircraft being stationary in the windshield.

"The GA-8 was also 500-600 feet higher. 2 miles and 500 feet doesn't seem like something to worry about with visual separation."

This is a little concerning Andrewr. The big picture here is that a jet's airspace was compromised by a light aircraft. This IS something to worry about.

andrewr
31st Jan 2017, 10:30
Are you serious? They are on a collision course!

Have you carefully looked at the data in the report? I have, probably a dozen or more times now. Even with the worst interpretation of the TCAS, the GA-8 was passing behind the jet (then somehow caught up after the jet turned final/upwind).

An object far away will appear stationary in the windscreen even if you're not on a collision course. The "stationary in the windscreen" idea is that it remains stationary up to the point of impact. You don't run into everything that appears stationary in the windscreen.

At the beginning the jet was on base leg about 2.5 - 3 miles out, and the tracks suggest it was about 90 seconds from the threshold (does that sound the right ballpark?)

The GA-8 was on a 4.5 mile final which I would expect to take 3-4 minutes, giving around 2 minutes separation at the threshold.

If the jet continued straight from base leg and crossed final at 90 degrees things could have been close, but they don't, they have to turn final which puts them well ahead of the GA-8 and you would expect separation to increase from there.

This is a little concerning Andrewr. The big picture here is that a jet's airspace was compromised by a light aircraft

If 2 miles and 500 feet isn't sufficient then what is? CASA recommend 2000 AGL overflys - 500 feet above the high performance circuit height - so they presumably think it's OK. The only alternative is no RPT without CTA - and that equation is pretty much guaranteed to give less RPT not more CTA.

I don't see any evidence that the jets airspace was actually compromised. It's all about the TCAS which has some very suspect numbers for the horizontal position. If the TCAS data didn't show the suspect 200' 1/8 mile data, would there have been any investigation?

Utradar
31st Jan 2017, 10:52
I presume the ATSB interviewed the crew and other pilots so the report is a fact finding exercise.

So the data would be from a combination of reports from crew, other pilots, ATC and TCAS data to get an accurate picture. A combination of TCAS alerts and a visual confirmation from the crew obviously paint a clear picture. Andrewr, you seem to basing your judgement only using the TCAS data. Did you interview the crew and other witnesses. I'm sure the ATSB did.

If 2 miles and 500 feet isn't sufficient then what is?

I'll keep it simple. The point is that both aircraft were aiming for the same runway and both didn't know each other were there. This is the 'scary bit'

Just saying ok

Lead Balloon
31st Jan 2017, 22:03
It's pointless trying to reason with these people, andrewr. In their world, merely seeing another aircraft in uncontrolled airspace is a collision risk.

The irony is that XGA was not the aircraft that came closest to ZPJ on that flight.

The other irony is that if ZPJ had had no TCAS, it would have just been another ordinary day at the CTAF and we wouldn't have to put up with all this posturing on PPRuNe. Just as ZPJ was blissfully ignorant of the aircraft that came closest to it on that day, ZPJ would have turned final blissfully ignorant of XGA behind it and losing ground on the straight in approach.

The passengers of ZPJ should count themselves lucky that the 'mutually agreed' separation strategy did not result in a mid air during the unnecessary go around.

Biatch
1st Feb 2017, 02:44
Respectfully, the only posturing I see here is from you two.

Insisting that these guys simply being pilots by talking to other pilots to try and ensure the safety of their aircraft is "amateur ATC" is stupid. Show me a pilot of any caliber that will sit in silence during an impending collision, and I'll show you a fool.

Insisting on referring to TCAS data that you yourself recognise is not accurate, to say that there would have been possibly no conflict is silly. TCAS is not designed to give exact data for the purposes of incident investigation. The ATSB simply provide its data because it is the only data available to try and help describe the event.

Insisting that two aircraft of greatly different categories, one on base, one on final, with no knowledge of each other is not a significant collision risk is beyond silly.

It's really seems that you have your nose out of joint for some reason. Perhaps you were involved in either this or another incident... whatever it was, I hope that your posturing doesn't prevent you learning from and seeing a risk to you and your passengers in the future.

Lead Balloon
1st Feb 2017, 03:08
You assume there was an "impending collision".

You assume there was "a significant collision risk".

You assume that decisions to mitigate collision risks - actual or perceived - necessarily result in a reduction in risk.

You assume that because TCAS data was the only data available it is somehow more accurate.

It really seems that you're yet another person who cannot entertain the possibility that the reaction in the circumstances resulted in ZPJ and XGA getting closer than they otherwise would have. And it seems you're yet another person who is unable to comprehend what I have written repeatedly in this thread about my frequent and voluntary engagement in mutually agreed separation arrangements in CTAFs.

"Amateur ATC" is an accurate description, except in the cases in which the pilot/s happen to be holders of a current ATC licence.

Biatch
1st Feb 2017, 03:27
I don't assume anything, I believe the pilots of the day. I believe "stationary in the window" equals collision risk.

I didn't not say that the TCAS was accurate, learn to read. I said it wasn't. I said it isn't designed for incident analysis. I said YOU keep referring to its inaccuracies in order to say that there was no issue. FORGET the TCAS.... read the report ... "Stationary in the window"...


https://www.casa.gov.au/file/110651/download?token=_tsIbwnK

"The unfortunate as- pect of this is that a target that moves relative to the observer is not generally a collision risk. If two aircraft flying on a constant heading and at constant speed are going to collide, they will maintain a constant relative bearing to one another and appear to remain station- ary in the windscreen (see figure 2)."

https://www.faasafety.gov/gslac/ALC/libview_normal.aspx?id=6851

Blossom Effect
This limitation is compounded by the fact that at a distance, an aircraft on a collision course with you will appear to be motionless. It will remain in a seemingly stationary position, without appearing either to move or to grow in size for a relatively long time, and then suddenly bloom into a huge mass filling one of your windows. This is known as "blossom effect." Since we need motion or contrast to attract our eyes' attention, this effect becomes a frightening factor when you realize that a large bug smear or dirty spot on the windshield can hide a converging plane until it is too close to be avoided.

Tell me this is not a risk. Tell me you would have said nothing.

Lead Balloon
1st Feb 2017, 03:40
You evidently either haven't read through this thread or haven't comprehended what was said.

It was only a page ago that andrewr said:An object far away will appear stationary in the windscreen even if you're not on a collision course. The "stationary in the windscreen" idea is that it remains stationary up to the point of impact. You don't run into everything that appears stationary in the windscreen.If you'd read and comprehended earlier pages, you would know that I initially identified the "stationary in the window" fact as conclusive of a collision risk. I then considered and researched what andrewr posted, and changed my view.

I call that being "objective".

If you'd read and comprehended earlier pages, you would know that I have never suggested that the pilot of ZPJ should have "said nothing".

A test of your objectivity: Does any and every decision to mitigate a collision risk - perceived or actual - necessarily reduce the risk of a collision?

If you take a deep breath, think about the question and resist the urge to quote the number of hours in your logbook, you should answer: No.

That's my point.

Biatch
1st Feb 2017, 04:26
Ha, the chip on your should is so blinding its now funny. I've never referred to hours in my logbook...

To answer your question, no it doesn't. Happy? It's irrelevant however. I still fully support their actions to mitigate a real risk they encountered. You may not run into everything that's stationary in the window, but that still leaves the door open to something. And these guys were not distant... so that door is wide open...

You know, I entered into this conversation to provide a perspective that you seemed interested in understanding. Pointless though, it seems you are more interested in beating your chest. "Posturing", "amateur atc", "hours in logbook" are all terms used to inflame and insult the people you share the sky with. Good luck to you mate...

Lead Balloon
1st Feb 2017, 05:28
So, you've correctly acknowledged that not all decisions to mitigate a collision risk - perceived or actual - necessarily reduce the risk of a collision.

Are you also prepared to acknowledge that it is possible - just possible - that the decisions made in this case resulted in an increase in the risk of a collision? Just possible?

You will hopefully not dispute the fact that even though the decisions were made with the best of intentions, those intentions do not alter the objective risks arising from the implemented decisions.

If it were true that the decisions made in this case did result in an increase in the risk of collision, would you agree that it might be appropriate to consider how to reduce the likelihood of those decisions being made? I note the sentence starts with an "if".

Biatch
1st Feb 2017, 06:12
Mate, you don't get it do you. You are now well into the rhelm of armchair quarterbacking.

Utradar
1st Feb 2017, 06:25
You assume there was an "impending collision".

You assume there was "a significant collision risk".

You assume that decisions to mitigate collision risks - actual or perceived - necessarily result in a reduction in risk.


No one's assuming anything LB except for you by the sounds of it. Im reading a factual report from the ATSB and you sound like you disagree with it? Did you investigate and interview everyone involved? I think I'll choose to believe the ATSB.

LB, I dont know why you're hung up on the decisions the pilots made to go around. The report says the crew of the jet were not stabilised so couldn't continue the approach so broke off to the south (dead side of circuit).

From the report: 'After receiving an acknowledgement from the pilot of XGA, the flight crew on board ZPJ turned their attention to the execution of their go-around manoeuvre as their turn onto the final leg of the circuit was late due to their preoccupation with monitoring XGA.

and here;

The PF on board ZPJ decided to discontinue their approach to land on runway 09, as they were too late for their turn onto final and therefore not in a stabilised condition.


It's pointless trying to reason with these people, andrewr.

hmmmm that's funny :8

Lead Balloon
1st Feb 2017, 07:29
The "factual report" from the ATSB is based on TCAS data.

Let's assume for the moment that the TCAS data is accurate. During what manoeuvre does the ATSB report say the aircraft were at their closest?

Why was XGA at that position?

Lead Balloon
1st Feb 2017, 07:41
Post #90:No one's assuming anything LB except for you by the sounds of it. ..Post #81I presume the ATSB interviewed the crew and other pilots so the report is a fact finding exercise.Should I presume that you assume presume means something substantially different from assume? Or that more than one person has the Utradar login?

Utradar
1st Feb 2017, 07:52
This is getting tiring LB

'It is not a function of the ATSB to apportion blame or determine liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings.'

The "factual report" from the ATSB is based on TCAS data.

TCAS was only one method of data used.

From the report:

'The flight crew looked out the right window of the flight deck and identified the traffic to their right and high against the skyline. The traffic appeared to them to be stationary in the windscreen relative to their own aircraft and with a high closure rate.

So, it's also based on crew observations and XGA pilot and maybe others who were presumably contacted for their story.

You tell me why XGA was in that position? :rolleyes:

Utradar
1st Feb 2017, 07:55
. Should I presume that you assume presume means something substantially different from assume? Or that more than one person has the Utradar login

OMG :ugh::{

Lead Balloon
1st Feb 2017, 08:07
It's getting tiring for you because you do not want to address the substance of the points I am making.

According to the "factual" report, the aircraft were at their closest during the go around manoeuvre and XGA was at that point as a consequence of the 'mutually agreed' decision that XGA turn toward that point.

What do you think would have happened if the pilot of XGA had instead simply pulled the nose up, put the flaps down and slowed to 60kts IAS?

Are you capable of considering whether actions other than those that occurred would have resulted in a different and lower risk of collision than the risk you perceive?

Utradar
1st Feb 2017, 08:52
. Are you capable of considering whether actions other than those that occurred would have resulted in a different and lower risk of collision than the risk you perceive?

LB likes chasing LB's own tail

1698

bolthead
1st Feb 2017, 10:05
So if you're imitating a space shuttle, how long does it take to slow to 60 knots?

Lead Balloon
1st Feb 2017, 10:34
A long time.

But an Airvan is not a space shuttle.

That's kinda my point.

Compylot
1st Feb 2017, 14:50
There are many presumptuous assumptions that are assumed by some who like to assume.

But at the end of the day when you are assuming assumptions it is best done with an audience who like to listen to such assumptions being assumed.

If your own particular assumptions aren't assumed in such a way that you would assume them the same yourself, then it is hard to convince others that your own assumptions are correct.

Of course sometimes, when you are trying to convince others of your assumptions and they keep staring at your mouth wondering why your uvula is upside down, it doesn't take a genius to quickly come to the assumption that it's really just the top of a rather large branch that's come all the way from your anus and is poking up out the top of your throat.

It's called having a big stick up your arsehole.

That's kinda my point.

kaz3g
2nd Feb 2017, 10:18
There's difference in airmanship and professionalism between RPT pilots and 'casual' pilots. It's usually ends up being the casual pilots who make it difficult for the RPT guys due to lack of skill, awareness, experience etc. That's why the initiative of separation by radio usually comes from the RPT pilots.

I think it's more than a little sad that this unfortunate statement seems to lie behind the views of some of you. I have friends who have flown GA all their lives and have accrued in excess of 10,000 hours without blameworthy incident doing so. As soon as you who fly RPT stoop to this you detract from your otherwise "professional" image and demonstrate you have forgotten your roots. Many of you will not yet have amassed the hours that your GA instructor had back when you were ab initio.

I'm not in that sort of league by a very long shot but I try to be "professional" in what I do in the air and on the ground to the best of my ability. Like my many flying friends, I routinely wait to the side to give a bigger aircraft a clear run and sometimes I get a "thanks" in return.

A little respect and thoughtfulness for our fellow pilots goes a long way...I call that airmanship.

Lead Balloon
2nd Feb 2017, 19:29
Well said, kaz.

I've asked third parties to read through this thread. You won't be surprised as to whose posts they consider puerile, childish and unprofessional.

As I said earlier in this thread, the attitude manifested in the sentences you quoted is an insight into the author's view of the author's own skills when s/he was flying 'mere' GA aircraft.

Utradar
2nd Feb 2017, 21:59
Kaz, this shouldn't be about 'us' and 'them'. We're all in this together because no one wants a mid-air.
My comments were made in context to my previous statement. The number of times I have heard of aircraft being in a CTAF (circuit) unbroadcast is countless. I've experienced it over the years and so have my colleagues. All have been GA aircraft. I've NEVER had unbroadcast RPT traffic appearing in the circuit.
This comment is not directed at all GA pilots.

Lead Balloon
3rd Feb 2017, 04:20
The number of times I have heard of aircraft being in a CTAF (circuit) unbroadcast is countless.That is patently untrue. That kind of hyperbole is not engaged in by professionals.

The number can be counted. And it won't be that big a number.

Could you please:

(1) confirm that the CTAFs to which you refer were ones in which the carriage of VHF was compulsory, and

(2) state, by reference to regulatory requirements, the calls that were compulsory but not made in those CTAFs.

kaz3g
3rd Feb 2017, 06:42
Hearsay doesn't persuade me, but facts do. It certainly shouldn't be about us and them and I'm reassured to see you assert that.

There are many CTAFs where no radio is required but few of them receive heavy metal. One of the issues that I have encountered on a few occasions is the 30 NM straight in announcement of the biggie occurring concurrently with the 10 NM inbound call from a little one. You guys approach around 3x my airspeed...hence the transmission over.

I remember flying in to BHI a few months ago getting a little wake up when the big fella gave a 5 NM as well because that was the first I heard him. I listen to just one channel at a time so I sometimes miss the area call.

I'm aware that I'm not easy to see, that I slow to less than 55 downwind and my final approach is under 50 KN and I let others know this if they join my circuit.

I'm very conscious of wake turbulence and often dag around in an orbit if I have stood aside for one of you guys. And I've had one or two Kingair drivers slow down to let me in first because they haven't forgotten this (thanks Michael).

But what I'm really trying to say is that almost all the GA folk I know try to do exactly that, too. And most of the heavy metal drivers are equally thoughtful.

The failure of just a few to demonstrate their courtesy and professionalism from either group should bring us closer together so we stamp it out...not be a source of dispute between us.

If we collide, I'll spoil your day probably even more than you will spoil mine. Let's make sure it never happens, eh? Peace

Kaz

Utradar
3rd Feb 2017, 07:41
Thanks Kaz,

I completely agree. We need to work together to make flying safer without the benefit of ATC in the interim. How: By being professional? Yes. But can we rely on it? No

The problems that every aviator should be asking, as a result of this incident is; what is the Department doing to address it? Is there a problem??

Would there be an inquiry into procedures/airspace if there was a loss of life in excess of 80 people and two aircraft destroyed? Simply put, it seems that because it didn't happen, nothing to see here - no problem. What a mentality! This should be a wake up call to to everybody!

Lead Balloon
3rd Feb 2017, 09:09
No. Nobody needs "the Department" to do anything.

The rules are clear.

Who broke those rules in this case?

Capn Bloggs
3rd Feb 2017, 09:17
Who broke those rules in this case?
Is this some sort of quizshow? Or don't you know?

Actually, LB, no rules were broken. If you were less hung up on Amateur ATC and hypothetical go-rounds that may or may not have caused the sky to fall in, you may, by now, have worked out the big picture here.



The "department" does need to do something.

kaz3g
3rd Feb 2017, 09:32
I see there is renewed pressure on ASA and all to review CAAP 166 but my personal view is that the concerns are somewhat misconceived.

I routinely listen out on Area when travelling in remote areas and am very glad to have the ability to contact Centre if things go wrong for me (or someone else in the vicinity). I'm generally higher than 5000' and what is going on at some unmarked airstrip is of little concern to me then.

I enjoy hearing what you big fellas are up to and, on one occasion, was very glad my engine problems could be relayed by someone 25000' higher than me.

I spend quite a bit of time each year in these places and that camaraderie between pilots of things great and small is something very special.

I had to laugh,even though rather stressed, on my last trip into the Alice because I reported at the Well and gave an estimate but the thermals were wild and I actually had to slow down to get my airspeed back in the green. The tower called me up and asked "where are you?.". I told them I had been a bit delayed and why. They also gave me an update on the ATIS and the crosswind...which was horrific...and I suggested I might orbit a few times while they got their two RPT away. I explained that a 25 KN gusting x-wind was a tad more than the 9kn max for the AUSTER. They agreed. A few minutes later they gave me a clearance and I asked if the grass was available. Long pause and "negative, why?" I said I thought it might be "ugly"! There is a God and the wind was straight down the runway when I landed.

its much better when we work together. God knows it's hard enough to keep tthe hours rolling over without petty fights between us.

Kaz

Utradar
3rd Feb 2017, 11:24
I see there is renewed pressure on ASA and all to review CAAP 166 but my personal view is that the concerns are somewhat misconceived.

Why is that Kaz?


CAAP 166

December 2013
Why this publication was written

This publication was written to provide advice on the limitations of ‘see-and-avoid', and on the use of radio to provide ‘alerted see-and-avoid', in order to enhance and maintain separation in a busy air traffic environment. It provides practical advice to pilots on their role in collision avoidance through the see-and-avoid principle to prevent mid-air collisions or airprox events, particularly in the vicinity of non-controlled aerodromes.

Keep reading and the Advisory publications keeps telling you the limitations of the system.

Here; 'The concept of see-and-avoid is far from reliable [ATSB].'

And here; '7.4 Pilots should also be aware that two aircraft converging on a point have the potential to remain fixed in one or both pilots' field of view, i.e. their relative position (in the windscreen) won't change until moments before impact.'

And here;

9.4 Pilots must realise that this process takes time; and human deficiencies can reduce the chances of a threat being detected and avoided. The factors affecting lookout may not be errors or poor airmanship, but limitations of the human visual and information processing systems which are present to various degrees in all humans.


9.3 As threats are external to the aircraft, an effective lookout must be maintained. The pilot must: consistently look outside the aircraft, search the available visual field to detect threats that will probably appear in the peripheral vision; shift vision directly to the threat and, if identified as a collision risk, decide on what effective evasive action to take; and manoeuvre the aircraft to avoid collision or an airprox event.

Then apply all this to a large RPT aircraft in a circuit.

CAAP 166 needs to be reviewed!

Capn Bloggs
3rd Feb 2017, 12:11
That is why the whole concept of "See and Avoid" is complete codswallop, and why "Amateur ATC" has for decades kept aeroplanes apart, and will keep them apart for decades to come.

Big aeroplanes need to operate with some sort of vertical or horizontal segregation until one (preferably both) crew sees the other aeroplane and is able to avoid the other aeroplane visually. That is precisely why every aerodrome that fields a large RPT service has mandatory radio requirements.

The recent hoo-har has been created in large part by You Know Who meddling with a system that worked well (as I alluded-to a few pages back).

Lead Balloon
3rd Feb 2017, 19:56
That is precisely why every aerodrome that fields a large RPT service has mandatory radio requirements.And what are those requirements? What are the "mandatory" calls?

All I'm seeing is a bunch of self-proclaimed professionals who make up their own rules because they:

- either don't know or don't agree with the current rules, and

- either can't or won't rationally assess collision risk.

gassed budgie
4th Feb 2017, 16:38
That is precisely why every aerodrome that fields a large RPT service has mandatory radio requirements

The last time I could be bothered looking, it read 'recommended' for my home field.

Lead Balloon
4th Feb 2017, 20:01
The carriage of VHF is mandatory at some uncontrolled aerodromes (although there are exceptions to even that rule).

There are no - repeat no - mandatory calls. The only time you're obliged to pipe up is if it is reasonably necessary to do so to avoid a collision, or the risk of a collision, with another aircraft.

The problem is that pilots who don't spend much (or any) time in the vicinity of other aircraft tend to grossly overrate collision risk. Some of the posters in this thread need to spend time at places like YMRY. RPT, ultralights, GA, EMS helicopter, parachuting, seaplanes ...

Utradar
4th Feb 2017, 20:43
There are no - repeat no - mandatory calls

You've got to be kidding! You're seriously joking aren't you? Who else thinks this way?? Read the rules.

Here;

Communications - 1.2.1.15.1 Pilots operating at, or in the vicinity of non-controlled airports where the carriage of radio is mandatory should always monitor the CTAF and broadcast their intentions at least in accordance with the minimum calls set out in the table below (Summay of broadcasts – All aircraft at non-controlled airports). Pilots should also make additional broadcasts when considered necessary to minimize any risk of collision (CAR 166 C (2)).

The carriage of radio is mandatory at MOST uncontrolled aerodromes. Most major uncontrolled aerodromes are certified and registered aerodromes.

Just hope I'm on the ground when you're in the air.

The name is Porter
4th Feb 2017, 22:00
There are no - repeat no - mandatory calls. The only time you're obliged to pipe up is if it is reasonably necessary to do so to avoid a collision, or the risk of a collision, with another aircraft.

Lead Balloon is correct :ok: If people concentrated less on the anality of operating in Australian airspace and concentrated more on a bit of uncommon sense none of this crap would happen!

Lead Balloon
4th Feb 2017, 22:09
There are no - repeat no - mandatory calls.

Utradar: You are evidently incapable of distinguishing between guidance material and rules. At least we agree on one thing: I, too, hope you're on the ground when I'm in the air, because I understand the rules and you do not.

Capn Bloggs
4th Feb 2017, 22:13
LB, nobody has said there are mandatory calls. Get out of your ideology mindset. If you don't make the recommended calls, then I hope CASA jumps on you, as you are simply being an idiot, endangering the lives of others.

Lead Balloon
4th Feb 2017, 22:30
And what recommended radio calls were not made in the case ZPJ and XGA?

The most recent event that required me to take collision avoidance action in the circuit occurred after I'd made every recommended radio call. In some cases the amount of blabbing on the radio is itself a risk.

Here's a tip on airmanship that I got from someone wise: You should always assume there's someone in the circuit or on a straight-in approach without a radio or with it tuned to the wrong frequency. Always. And if you don't do that, you're the idiot endangering the lives of others.

Utradar
5th Feb 2017, 00:20
Communications - 1.2.1.15.1 is not guidance material, it's out of Jepp ATC and is rule based. CAAPs is guidance (advisory publication). Here you go, have a read, just trying to help.

'The information in this Airway Manual is extracted from Australian Aeronautical Information Publications (AIP), which provides the primary source of information concerning rules of the air and procedures for the safe and efficient movement of aircraft in Australian airspace. The Airway Manual information and/or the AIP should be read in conjunction with CASRs, CARs, CAOs and CAAPs which detail the statutory requirements.'

Here's a tip on airmanship that I got from someone wise: You should always assume there's someone in the circuit or on a straight-in approach without a radio or with it tuned to the wrong frequency. Always. And if you don't do that, you're the idiot endangering the lives of others.

And.......what are suppose to do about it if you see someone on a straight in approach, like on base for example. How do you manoeuvre a high energy jet to avoid a collision?

And what recommended radio calls were not made in the case ZPJ and XGA?

From the the ATSB: Both aircraft made the required broadcasts on the CTAF.

Lead Balloon
5th Feb 2017, 01:08
There are no - repeat no - mandatory broadcasts for use at aerodromes with CTAFs.

ZPJ still ended up on base and XGA on the straight-in, despite the broadcasts! Do you not comprehend the irony in you and the Capn throwing rocks at me for pointing out the fact there are no mandatory calls on a CTAF, when the very circumstances that gave rise to this thread were not avoided by broadcasts? Just a teensy bit of irony?

Do you think it would have helped or hindered if, just after XGA told ZPJ that XGA was on the straight-in, I'd piped up and broadcast: "Mildura traffic, Skipper ABC is one zero miles west, on descent from seven thousand five hundred, tracking for a straight-in approach runway 09, copied XGA and ZPJ and the twin joining crosswind, estimating 3 miles at time xy, Mildura." After all, it's "mandatory". Maybe, in the interests of safety, I could have requested everyone to report clear of the runway and tell me what the windsock was doing.

Helped or hindered?

What are you going to do in your high energy jet? Evidently you are just going to look ahead and crash visually. (Tell me that you're not qualified to seat 0A in a transport category aircraft. Please.)

You keep conflating "seeing" another aircraft with a certain collision risk.

If you get a TCAS TA in controlled airspace, what do the rules oblige you to do, and why?

Capn Bloggs
5th Feb 2017, 03:02
And what recommended radio calls were not made in the case ZPJ and XGA?

Who said the recommended calls were not made?

Do you think it would have helped or hindered if, just after XGA told ZPJ that XGA was on the straight-in, I'd piped up and broadcast: "Mildura traffic, Skipper ABC is one zero miles west, on descent from seven thousand five hundred, tracking for a straight-in approach runway 09, copied XGA and ZPJ and the twin joining crosswind, estimating 3 miles at time xy, Mildura." After all, it's "mandatory".
It may well have done. Had the EJet turned away from XGA towards the west and started climbing to 3000ft AGL... right into your path, it would be good to know about them, wouldn't it. But no, the expert LB would just keep his trap shut because the call was only "recommended".

There are no - repeat no - mandatory broadcasts for use at aerodromes with CTAFs.
I'm glad you've finally worked that out. Better type it again just to make sure we know you know the rules.

There is no perfect system. The stupid part about this is that you are so wound up about mandatory this and that (the rules for which you obviously don't know yourself and are accusing others of saying or implying things they haven't) that you can't see what the real problem at Mildura was. Sad that such an attitude is sharing the skies with fare-paying pax...

Lead Balloon
5th Feb 2017, 05:18
Nobody said the recommended calls weren't made.

You said:If you don't make the recommended calls, then I hope CASA jumps on you, as you are simply being an idiot, endangering the lives of others.All I was doing was pointing out that the recommended calls failed abjectly to achieve their intended purpose.

Apparently in your world the choice not to make a call is more dangerous than a call that's made but not comprehended or over-transmitted. It's just kooky.

You don't like my "attitude"? I don't like your attitude. You put too much reliance on blabbing on the radio and assuming everyone else is blabbing as much as you about the things that you consider are worth blabbing about.

Fortunately the rule-makers haven't made the same mistake (touch wood).

You think my 10 mile call would have helped? I think you are wrong. Stubbornly and stupidly wrong. I think the last thing that ZPJ, XGA and the twin needed was me blabbing on the CTAF at a time they had much bigger issues to deal with.

You grossly overrate the infinitesimal small risk of ZPJ colliding with me on a go around to the west. Maybe in that scenario the most sensible point for me to pipe up would have been when ZPJ broadcast that it was going around towards the west? What do you do about all the aircraft with no radios and no transponders? Are you just blissfully ignorant of them or do you worry about them constantly too?

As a matter of interest, how many hours have you spent in seat 0A of an Airvan, or a 210, or Bonanza or a 172? And how recently?

Maybe part of the "problem" is that some of the people in seat 0A of the "high energy jets" don't have much experience in seat 0A of an Airvan or a 210 or a Bonanza or a 172. That's not their "fault", but it does mean they may not have much insight into the capabilities of other aircraft.

I'm struck by the irony that on the most recent occasion that I volunteered to orbit away from an aerodrome so that an aircraft could get in ahead of me - my ETA having been about minute ahead of his - the aerodrome was none other than Mildura. The pilot requested that I expedite my taxi off the runway as his ETA was a minute behind mine. I instead volunteered to orbit away from the aerodrome. He thanked me after landing. I said: "It was pleasure, sir." I meant it.

But you don't strike me as the kind of person who'd stoop to saying please when in Skygod mode, administering your rules in your way. At least you're confined to your heart of darkness and won't be bothering us at YMIA.

Utradar
5th Feb 2017, 05:50
Has anyone else considered the danger of dropping in to Mildura with one radio call for a straight in approach 11'130 ft at 10.5 nm and a speed of 140-150 kt at 5nm. I wouldn't call that very safe.

From the ATSB report, no other calls were made by XGA, probably not wanting to 'blab' away and it even says 'The pilot of XGA was probably not monitoring Mildura CTAF when the PM on board ZPJ broadcast joining the Mildura circuit.'
Was probably 'blabbing away' on company frequency talking about spinning an Airvan. Pilots head with no brains due spin testing.

Sounds safe to me. :ugh:

Capn Bloggs
5th Feb 2017, 07:16
Yes, Ut, I noted that earlier in the thread. As well as concentrating too much on not stacking it on his Stuka arrival, he doesn't make it easy for others to spot him whilst they are doing their approach.

LB, I think you are on something. I really am having trouble understanding what your point is, apart from being just a usual rant against all things "mandatory".

Apparently in your world the choice not to make a call is more dangerous than a call that's made but not comprehended or over-transmitted. It's just kooky.

Kooky? Where did I even suggest that someone deliberately over-transmit, or make a call that would not be comprehended?

I'm struck by the irony that on the most recent occasion that I volunteered to orbit away from an aerodrome so that an aircraft could get in ahead of me
My hero, except that I make sacrifices for lighties all the time when we clash. A good bit of amateur ATC, like slowing down, maybe doing a track-stretching dogleg, perhaps me overflying, getting them to keep the speed up, maybe ask them for an orbit on DW or to extend upwind.

You: Do you think it would have helped or hindered if,

Me: It may well have done...

You: You think my 10 mile call would have helped? I think you are wrong. Stubbornly and stupidly wrong.

Nice reaction. Thanks for seeing my point of view. I knew you'd come round eventually.

All I was doing was pointing out that the recommended calls failed abjectly to achieve their intended purpose.

Apparently in your world the choice not to make a call is more dangerous than a call that's made but not comprehended or over-transmitted. It's just kooky.
So, not knowing how a call will actually work out, you would rather not make it. Complete lunacy (given, of course, that I would not make a call at 10.0000nm if someone was already transmitting).

For all your ranting and raving, there haven't been too many suggestions from you about how things could be improved to reduce the chance of this incident happening again.

kaz3g
5th Feb 2017, 08:12
Ban straight in approaches at certified and registered airports and make all aircraft join the circuit with appropriate call(s).

Remind all pilots that the first rule of flying into a non-towered field is "see and avoid".

And if GA8's are hard to see, how much harder would a glider from the strip 2nm to the SSW be?

Kaz

Compylot
5th Feb 2017, 10:14
What happened Leadsie?


Are you living in your brothers shadow?


Did you fail Psychometric testing when going for the cadetship? (Very Likely!)


Or are you colour blind?


I can imagine that the next time you're inbound and you hear the dreaded Skygod making their CTAF call, sounding like a try hard amateur ATC, your sweaty palms will grip that bit harder on the yoke.


Muttering and cursing under your breath you'll open up the throttle, **** the lean of peak, you'll be going full rich today baby!


You don't have to make any damn calls, because you don't bloody have to!


You know where you are, what you are doing and how you're going to bloody well do it!


Those Skygods can see you from their privileged seat 0A, on their fancy equipment, sipping their Lattes and smirking slyly at the sexy flighty in the jump seat who's showing a bit of leg. They don't have time to look out the window!


Later that Friday night, in the Aero Club bar, you'll grip your yoke even harder as you regale tales of heroics operating into CTAFs amongst the Skygods.


A legend in their own lunchtime.


And I thought that I was good :sad::eek:

wishiwasupthere
5th Feb 2017, 10:30
So good Compylot! :}:D

Lead Balloon
5th Feb 2017, 19:16
I'm not even a pilot.

I just enjoy goading self-proclaimed "professionals" into saying very childish, unprofessional things, while demonstrating their lack of comprehension skills and ignorance of the rules.

Utradar
5th Feb 2017, 21:42
Huh, just goes to show why you don't understand the complexities of this incident.

I've flown more approaches in my aircraft than the pilot of ZPJ has flown in the type that ZPJ is.

Lead Balloon
5th Feb 2017, 21:54
And if GA8's are hard to see, how much harder would a glider from the strip 2nm to the SSW be?As I said earlier in this thread:The irony is that XGA was not the aircraft that came closest to ZPJ on that flight.

The other irony is that if ZPJ had had no TCAS, it would have just been another ordinary day at the CTAF and we wouldn't have to put up with all this posturing on PPRuNe. Just as ZPJ was blissfully ignorant of the aircraft that came closest to it on that day, ZPJ would have turned final blissfully ignorant of XGA behind it and losing ground on the straight in approach.Yet what is all the sound and fury above about? Radio broadcasts! Even when it's pointed out that all of the recommended radio broadcasts were made in this case but they nonetheless abjectly failed to avoid ZPJ being on base when XGA was on the straight-in. I'm the idiot endangering the lives of others by choosing not to broadcast at a time when ZPJ and XGA (and the twin) had more important things to concentrate on and communicate about. Ban straight in approaches at certified and registered airports and make all aircraft join the circuit with appropriate call(s).Unfortunately, change fatigue means that each time there's yet another change of the rules there's usually a doubling in the number of variations in strong opinions about what the rules are and a quadrupling of the number of variations in procedures. (That's why I do actually sympathise, at one level, with people who make up and pontificate about their own 'rules'. It's what happens in the vacuum left by a regulator which couldn't manage a fart on a diet of baked beans.)

And the "high energy jet" drivers prefer to have the option of straight-ins ...Remind all pilots that the first rule of flying into a non-towered field is "see and avoid".After all the sound and fury about the limitations of "see and avoid" die down, it's still the rule in VMC for IFR and VFR aircraft. All pilots should always assume there are aircraft around without radio or transponders, aircraft with radios tuned to the wrong frequency and aircraft doing unusual things close to aerodromes.

Utradar
5th Feb 2017, 22:06
All pilots should always assume there are aircraft around without radio or transponders, aircraft with radios tuned to the wrong frequency and aircraft doing unusual things close to aerodromes.

And is exactly why the rules need reviewing to increase safety by increasing margins for RPT aircraft. You said it yourself.

I could write a thesis on the limitations of see and avoid and issues with jets operating at non-towered aerodromes. The ATSB has made this plainly obvious over the years. Even CASA with their CAAPS have made it obvious. It's almost a disclaimer!

Lead Balloon
5th Feb 2017, 22:32
A "review of the rules".

That's comedy gold.

Why am I not surprised that you could write a thesis on the limitations of see and avoid. You and compylot are obviously at the very academic phase of your budding aviation careers.

The Capn, on the other hand, is not at that phase. His outlook has been determined by the fact that most of his aviation career has been spent in an environment in which everyone is controlled and everyone must obey orders. He therefore has, unsurprisingly, considerable difficulty in operating in environments in which others may have the discretion to make independent decisions with which he may disagree or which aren't dictated by orders.

Utradar
5th Feb 2017, 22:38
. A "review of the rules".

That's comedy gold.

There would have been if there was an accident. Well done LB

Lead Balloon
5th Feb 2017, 22:42
So the current rules were not formulated taking into account the well-known limitations of see and avoid?

What are the 'in vicinity' rules about, if not collision avoidance?

What would the review produce? Yet more rules?

Capn Bloggs
5th Feb 2017, 22:53
The norm is "there's no such thing as a stupid question". That doesn't apply in this case.

Lead Balloon
5th Feb 2017, 22:56
So you're the expert:

Write the new rules you want.

Then explain how your rules would be the first in history to guarantee that none of the collision risks you perceive will arise.

Utradar
5th Feb 2017, 22:59
So you're the expert:

Write the new rules you want.

Then explain how your rules would be the first in history to guarantee that none of the collision risks you perceive will arise.


Perceive??? This report is all about a near collision with a jet. It's obvious to those who are 'listening'.

Lead Balloon
5th Feb 2017, 23:03
OK then, expert:

Write the new rules you want to prevent the actual "near collision".

Utradar
5th Feb 2017, 23:12
That's not my job, but I'm happy to offer advice.

BTW I'm no expert. That's just you being facetious.

If new rules bring along more safety for RPT aircraft then I'm all for it. It's time to stop saying it's a perceived risk. The report is right under your nose.

Lead Balloon
5th Feb 2017, 23:18
What is your advice?

What would the effect of the rules be that you would change or introduce to "bring along more safety for RPT aircraft"?

The report that's right under my nose is based on TCAS data that the report itself says in "indicative only". BTW: You haven't answered my question about what the rule is for an aircraft that has a TCAS TA in controlled airspace, or why that rule says that.

If all you can do is say "this isn't good enough and someone else should do something about it", I'd advise you not to hold your breath waiting.

Utradar
5th Feb 2017, 23:23
The report that's right under my nose is based on TCAS data that the report itself says in "indicative only".

WRONG!

Crew observations and interviewed witnesses were among others used for the report.

What relevance does your TCAS TA in controlled airspace have to this discussion?

Lead Balloon
5th Feb 2017, 23:35
Was the pilot of XGA interviewed?

You're obviously very proud of your masterpiece, so you should have first hand-knowledge of whether the pilot of XGA was interviewed.

The closest point of the "near collision" is based on TCAS data.

The relevance to the rule in controlled airspace is relevant to the well-known limitations of TCAS and the well-known natural propensity to react in a particular way.

Utradar
5th Feb 2017, 23:51
You keep assuming that the only method of getting the facts is from TCAS data. You tell me if the pilot was interviewed?

Of course TCAS has limitations and is another reason not to rely on it for separation. The CAAPS recommend it and is why it needs reviewing. Im led to believe by your post that you agree. Crew observations in the report mention the two aircraft were on a collision course without prior warning.

Capn Bloggs
5th Feb 2017, 23:59
The relevance to the rule in controlled airspace is relevant to the well-known limitations of TCAS and the well-known natural propensity to react in a particular way.
Enlighten us, LB. What is this "well-known natural propensity to react in a particular way"?

The TA would probably have been an RA but the EJet was too low.

Must be hard, LB, arguing about things you know nothing about, not being a pilot and all. Your brain's trust must be working overtime what with all their CTAF+jet experience...

Lead Balloon
6th Feb 2017, 00:09
You wrote the report, Utradar. Was the pilot of XGA interviewed or not?

"The TA would probably have been an RA but the EJet was too low." Although my brains trust tells me that the RA function was probably disabled as a consequence of the Jet's height, they also say that your assertion that "the TA would probably have been an RA" is mere speculation. Given your propensity to exaggerate risks, that is unsurprising.

Utradar
6th Feb 2017, 00:11
I didn't write the report. I'm stating from the report that the crew observed XGA on a collision course.

Don't you believe the ATSB? That would make you a conspiracy theorist.

Lead Balloon
6th Feb 2017, 00:33
I'll track down the primary regulatory references, but meanwhile my brains trust tells me that this stuff from AC 12-55C, although merely guidance, does provide some relevant insights:k. TA Responses.

(1) Objective. To verify the pilot properly interprets and responds to TAs.

(2) Criteria. The pilot must demonstrate the following:

(a) The PF should continue to fly the airplane, and be prepared to respond to any RA that might follow. The PM should provide updates on the traffic location shown on the TCAS display, using this information to help visually acquire the intruder.

(b) Both pilots confirm that the aircraft they have visually acquired is that which has caused the TA to be issued. Use should be made of all information shown on the display, note being taken of the bearing and range of the intruder (amber circle), whether it is above or below (data tag), and its VS direction (trend arrow).

(c) Other available information is used to assist in visual acquisition. This includes ATC party-line information, traffic flow in use, etc.

(d) Because of the limitations that may exist with various display systems, the PF should not maneuver the aircraft based solely on the information shown on the TCAS display. No attempt should be made to adjust the current flightpath in anticipation of what an RA would advise.

(e) When visual acquisition is attained, right-of-way rules are used to maintain or attain safe separation. Do not initiate unnecessary maneuvers. The limitations of making maneuvers based solely on visual acquisition, especially at high altitude or without a definite horizon, are understood.I added the bolding to (d) and (e) because my brains trust considered them to be particularly relevant.

The natural reaction to a TA is to take avoidance action, particularly if you're someone with a propensity to overrate risks. For the reasons set out in the AC, the natural reaction may increase risks. Each time the Capn merely anticipates an RA he may be inadvertently increasing the risk of a collision.

Lead Balloon
6th Feb 2017, 00:40
Don't you believe the ATSB? That would make you a conspiracy theorist.More comedy gold!

You must have been hiding under a rock during the Senate's Aviation Accident Inquiry and when John Deakin wrote his article called "Lead In the Hogwash" about the ATSB's masterpiece report on the Whyalla tragedy.

I have complete faith and trust in the ATSB - to f*ck it up and fudge it when it's expedient to do so. And that's not a criticism of you, Utrader. It's a criticism of the people who've wrecked what used to be a credible organisation.

Capn Bloggs
6th Feb 2017, 00:41
Yep, assertion of a probability is mere speculation. I think. But then again, I would have thought an assertion involved claiming something as a fact. I'm struggling with the assertion of a probability. Let me think about it some more.

Given your propensity to exaggerate risks,
Do you have any evidence to back up that assertion or is it mere speculation on your part?

I might start writing for the department! :D

Although my brains trust tells me that the RA function was probably disabled as a consequence of the Jet's height
There you go, you learn something every day, although this fact/assertion/non-speculation is written in the report. Maybe you missed it. The trouble with reading and discussing things about which you know nothing is that these small although important details slip through the cracks. Tut tut. :=

Capn Bloggs
6th Feb 2017, 00:51
LB, you and your brains trust are an embarrassment, although I am relieved that I will never meet you in the air given you're not a pilot.

Each time the Capn merely anticipates an RA he may be inadvertently increasing the risk of a collision.
That is precisely what I do; if I get a TA, I anticipate that an RA will shortly follow and I am ready for it. A concept you obviously don't have a clue about. Next?

Utradar
6th Feb 2017, 01:13
More comedy gold

I seriously hope you're not a pilot or work for the Department because lives depend on how serious this is taken.

I have complete faith and trust in the ATSB - to f*ck it up and fudge it when it's expedient to do so.

With an attitude like that, you should be no where near aviation.

Lead Balloon
6th Feb 2017, 08:55
My apologies for the delay in responding. My brother said he had to use his computer. I couldn't practice more approaches on FlightSim until he'd finished.

What seems passing strange to me is that none of you (other than kaz, who is always a consummate professional) has actually proposed a solution to the problem you're having conniptions about.

I'm an idiot endangering others' lives, but only on FlightSim. Throw rocks at me as much as you like, but that won't change anything.

What do you say is the sensible and practical real-world solution to the problem of which you say the YMIA incident the subject of this thread is a symptom?

Mandatory radio calls? No straight-ins for non RPT aircraft? CAGRO? MBZ? AFIZ? D? C? B? Another avionics gadget?

What experiment do you actually want to run, or run again, to prove what's already been learnt over and over and over again?

And Utradar, I recognise that you're an earnest and honest investigator full of youthful exuberance, dedicated to making the world a safer place. More power to your arm. But you really do need to read the Senate's report arising from its aviation accident investigation inquiry (I didn't write it) and various other sources (not written by me) to understand why the ATSB's reputation has been trashed. I hope you help to restore it, but your contributions on this thread do not auger well.

The name is Porter
6th Feb 2017, 09:21
Ban straight in approaches cos 2 aircraft didn't see each other? FFS!

I've got a better idea, limit the circuit to one aircraft at a time, every aircraft can circle overhead at separated levels then let down one at a time, that'll fix it.

Capn Bloggs
6th Feb 2017, 09:51
What seems passing strange to me is that none of you (other than kaz, who is always a consummate professional) has actually proposed a solution to the problem you're having conniptions about.
I have actually, but you wouldn't have noticed because you do not know what you are talking about; you would have spotted my comments had you been a subject-matter expert, which you are not.

"Lead Balloon's" a good handle...

Lead Balloon
6th Feb 2017, 10:11
Hmmm.

Your post at 73:As Porter (I think it was) does: everybody clear off until RPT on the ground. That would solve LB's "suspected" problem that "May" or may not be a problem.Your post #76You are so blinkered that you can't even see the sarcasm in my suggestion that everybody rack off when I'm about.I may have missed your proposed solution that wasn't dripping with sarcasm, in which case that's my fault. My apologies.

Please just state your proposed solution, so that the people who aren't idiots like me can benefit from your experience and wisdom.

Capn Bloggs
6th Feb 2017, 12:34
Please just state your proposed solution, so that the people who aren't idiots like me can benefit from your experience and wisdom.
What, and cop another spray? I don't think so.

Utradar
6th Feb 2017, 20:35
Welcome back LB :ouch:

You've had your fair share of rock throwing and sarcasm too but I like your interest in finding solutions and I think that's important.

I've re-read through this thread and realise you may know more than you're letting on.

What aircraft would have come closer to ZPJ than XGA?

Limitations of the current system:
- No requirement for mandatory calls
- It's a big sky out there but gets smaller at a circuit
- See and avoid for a jet/turbo is difficult in a circuit due to workload and positioning for landing, speed and window size.
- TCAS difficult to monitor and interpret in a circuit due to delays in updating in turns and other limitations (non transponder equipped GA aircraft and Txpdr not being turned on)
- 2, sometimes 3 aerodromes linked to same frequency (Wentworth and Mildura for example)
- Company procedures of having 2 frequencies being monitored at the same time.
- Wake turbulence issues for smaller aircraft
- Manoeuvrability of larger aircraft to avoid collision
- More chance of conflict with 'Cowboys' due to non controlled environment

Now try asking Mr and Mrs ticket holder if they'd find this acceptable?

Proposed solutions:
- Towered aerodrome (too costly)
- Class E to the ground
- AFIS
- Unicom
- Straight in approaches only for RPT (less workload, more time to observe traffic visually and using TCAS, no banking obscuring other unsighted traffic (no delay in TCAS updates), higher on horizon (easier to distinguish from ground or circuit, landing lights on being seen longer).

Why should less manoeuvrable (bigger) aircraft have to give way to other traffic while on a straight in approach? Powered aircraft give way to gliders due to their limitations. Larger aircraft have more limitations.

Now please discuss without sarcasm or rock throwing.........

Utradar
6th Feb 2017, 21:15
(e) When visual acquisition is attained, right-of-way rules are used to maintain or attain safe separation. Do not initiate unnecessary maneuvers. The limitations of making maneuvers based solely on visual acquisition, especially at high altitude or without a definite horizon, are understood.

This bit is interesting. I notice that it doesn't mention the limitations of maneuvres at low altitudes.

This right of way rules stuff only works when both aircraft have TCAS warning systems, designed for higher altitudes. The two airvans didn't have TCAS and maybe a maneuvre was required to avoid a collision based on visual observation. I've repeatedly said the report shows the crew saw XGA on a collision course.

XGA didn't know ZPJ was on base and the TCAS alerted the crew to this. From the report, the closest the two aircraft got to each other was when ZPJ commenced the go-around.

So the closest point occurred just prior to or on commencement of the go-around.

Interesting.

andrewr
7th Feb 2017, 00:18
- Towered aerodrome (too costly)
Yes, too costly to be adopted.
- Class E to the ground
Wouldn't help for VFR traffic, BUT would be a good idea when you have multiple aircraft in IMC.

- AFIS
- Unicom

ATC Lite? Not sure of the cost/benefit, if traffic is not required to follow their directions.

- Straight in approaches only for RPT (less workload, more time to observe traffic visually and using TCAS, no banking obscuring other unsighted traffic (no delay in TCAS updates), higher on horizon (easier to distinguish from ground or circuit, landing lights on being seen longer).

RPT are free to do this already. However, when approaching the airport from the wrong direction it will add maybe 20 miles track? to position for a straight in.

It also puts aircraft on the runway alignment earlier and so may actually result in more conflicts if other aircraft also perform a straight in approach. It may move the conflict to e.g. 10 miles from the airport where there is more uncertainty about what frequency an aircraft will be on. Class E and straight in approaches only allowed for IFR aircraft? Maybe.

Why should less manoeuvrable (bigger) aircraft have to give way to other traffic while on a straight in approach? Powered aircraft give way to gliders due to their limitations. Larger aircraft have more limitations.

In practice, I suspect that it is rare for RPT on a straight in to have to give way to other aircraft. I doubt many people would turn base with e.g. RPT on a 10 mile final. If they do it is probably a misjudgment rather than asserting right of way.

Utradar
7th Feb 2017, 01:01
Good points Ar

RPT on a straight-in are still obliged to give way to circuit traffic by law. Straight- in arrivals may add 20nm to track but maybe it's small price to pay for perhaps more safety?

Class E and straight in approaches only for RPT could be answer or a combination of other suggestions.

Captain Nomad
7th Feb 2017, 02:19
straight in approaches only for RPT

RPT isn't the only category that operate bigger/faster aircraft which encounter these issues (biz jets for example). What about including turbo-prop/jet/any acft above 5,700 kg MTOW?

Lead Balloon
7th Feb 2017, 02:30
Towered aerodrome (too costly)

(Attempted irony, not sarcasm:) That sounds like "affordable safety" to me. Now try asking Mr and Mrs ticket holder if they'd find this acceptable.

And be careful: You'll be accused of drinking the Dick Smith cool-aid.

In all seriousness - and I'm sure you'll understand this - if you try to build a rational regulatory system on the basis of what the punters "find acceptable", you'll go - in no particular order- mad and broke.

You've identified "No requirement for mandatory calls" as a "limitation of the current system". The recommended calls were made in this case. They didn't prevent one aircraft ending up on base while another was on the straight-in. How would mandating them have made a difference?

As to the rest of your proposed solutions: more power to your arm. Go forth and implement or advise that they be implemented accordingly.

My only (serious) suggestions are that:

- The (average) seven flow-on effects of each change be identified and considered first. (Andrew and Capt Fathom have already alluded to some of those)

- Any changes be subject to more effective education campaigns than accompanied most other changes in the last 20 years.

bolthead
7th Feb 2017, 02:50
If all the recommended calls were made in this case, there wasn't nearly enough listening and comprehending going on.

Lead Balloon
7th Feb 2017, 02:51
The report says all the recommended calls were made.

Which is precisely my point.

Utradar
7th Feb 2017, 03:30
It's that simple eh? Nothing else going on, happy with the status quo? Risk levels acceptable? Leave it as it is, works fine huh? Same incident won't happen again?

Im seriously hope you're right and I'm wrong. Don't want it the other way, do we? It's well worth the discussion on here then.

Yeah that's what I meant Capt N, include that idea.

Lead Balloon
7th Feb 2017, 03:44
Errrrmmm, in case that was addressed to me, I reiterate what I said:

As to the rest of your proposed solutions: more power to your arm. Go forth and implement or advise that the be implemented accordingly.

My only (serious) suggestions are that:

- The (average) seven flow-on effects of each change be identified and considered first. (Andrew and Capt Fathom have already alluded to some of those)

- Any changes be subject to more effective education campaigns than accompanied most other changes in the last 20 years.

andrewr
7th Feb 2017, 05:59
One thing to remember is that we fly a circuit because it has been shown that OCTA a circuit reduces the risk of collision compared to a straight in approach.

The highest risk of collision is on final approach. The extended centreline tends to put multiple aircraft on exactly the same path. The circuit was designed to give aircraft a chance to locate each other BEFORE they turn onto final approach.

I don't think this situation would have been improved if both aircraft had been flying a straight in approach, or even if the roles had been reversed. OTOH if the GA-8 had flown a circuit instead of a straight in approach...

Utradar
7th Feb 2017, 06:49
That might work well for light aircraft but are you considering the workload of flying a jet in a circuit?

Search report 2008 Ambidji CTAF vs CTAF (R)

'Ambidji proposes CASA adopt a strategy whereby it strengthens existing barriers to ensure a more safe and efficient CTAF concept in the near term and only implements procedural changes to the concept following a formal review of the operational success of the strengthened barriers.'

Also refer to the 19 limitations of an alerted search

Capn Bloggs
7th Feb 2017, 07:10
That might work well for light aircraft but are you considering the workload of flying a jet in a circuit?
UT, nobody's forcing you to. If you are not comfortable, you can do a SI. Don't remove a safety and economic option because some aren't comfortable doing it.

OTOH if the GA-8 had flown a circuit instead of a straight in approach...
Not a bad idea considering he was 10k at ~10nm! Gross dereliction of airmanship in a CTAF IMO.

Lead Balloon
7th Feb 2017, 07:19
Maybe straight-ins should be available only to aircraft over 5,700Kgs MTOW. Make the rule and let's run the experiment.

On your workload point, Utradar, ZNJ flew a circuit despite the consequent workload. Any insights into why?

In the case of a high energy jet, at what distance from the threshold will it be joining the straight-in?

You do realise the 'big MBZ' (faux AFIZ) with mandatory radio calls experiment has already been run? Lots of people could dig out the old charts and run it again. Just say the word.

Capn Bloggs
7th Feb 2017, 07:31
Maybe straight-ins should be available only to aircraft over 5,700Kgs MTOW. Make the rule and let's run the experiment.

Maybe the kneejerkers should stay quiet...

Utradar
7th Feb 2017, 07:37
UT, nobody's forcing you to. If you are not comfortable, you can do a SI. Don't remove a safety and economic option because some aren't comfortable doing it.

Yep I know that but some juniors might not.


On your workload point, Utradar, ZNJ flew a circuit despite the consequent workload. Any insights into why?


No idea, you'll have to find and ask the pilots involved. I'm assuming you mean ZPJ??

I know the MBZ 'experiment' has been run but while we have jets operating into non-towered aerodromes, I think it's important, don't you?

Lead Balloon
7th Feb 2017, 09:15
It does not matter what I think or any of the thrusters on this thread think.

It is completely pointless to observe, on the one hand, that there's workload for jets that can be avoided by doing a straight-in rather than a circuit, and then declare "dunno" why the jet didn't do a straight-in when it was available.

It is completely pointless to declare knowledge of some system that was run in the past and then ask whether that was important.

Just do something, FFS. Implement the system you want. Do it.

Your opinion is that broadcasts should be mandatory. My opinion is that mandatory broadcasts are unnecessary and create their own risks. Fact is, the rules are on my side, not yours. Change those rules. Just do it. Don't have a pointless blabfest on pprune with dangerous idiots like me.

Most of the rules in Australia have been a special kind of stupid for a long time, and fortunately the rules have little-to-no causal connection with safety outcomes. So fiddle with them to your heart's content.

Just do it.

On eyre
7th Feb 2017, 09:35
Maybe as part of airmanship all pilots in CTAFs should be encouraged to have landing lights on where practicable within 10 mn of the circuit. I know I do always (with the limitation in some types of lights being only usefully on when the gear is extended) and so do all RPT.
Maybe only a small thing but would perhaps block one of the small holes in the Swiss cheese.

Utradar
7th Feb 2017, 09:40
:}Thanks LB, most of your comments are appreciated. I'm starting to work you out.

Your opinion is that broadcasts should be mandatory. My opinion is that mandatory broadcasts are unnecessary and create their own risks


Yair they do create their own risks when there's multiple airports using the same frequency, but when an RPT or large enough aircraft is on one CTAF frequency, I think the risks of a few calls on CTAF are more than managable for non-controlled airports in Australia. We're not like the US yet.

Just do it eh? Bit like Nike?

andrewr
7th Feb 2017, 09:41
he was 10k at ~10nm! Gross dereliction of airmanship in a CTAF IMO.

Looks like he joined the straight in at about 5 miles and 3500'. 6-700 feet per mile isn't an outrageous descent angle in a piston single. 3NM is generally considered the circuit area. What he does before joining the approach doesn't seem particularly relevant, unless you are proposing additional restrictions on operations within 10NM of an airfield?

andrewr
7th Feb 2017, 09:48
That might work well for light aircraft but are you considering the workload of flying a jet in a circuit?

Does flying downwind & base instead of a straight in impose that much additional work that it cancels out the advantages of better traffic awareness?

When were the rules changed to permit straight in approaches? I have a recollection of the rules saying 3 legs of the circuit must be flown, and that was changed at some point after I started flying - but I might be mistaken.

On eyre
7th Feb 2017, 09:48
But 6-700 feet per mile would take 5 minutes (give or take) meaning 60 kt G/S - don't think so. More like 120 kts meaning 1400 feet per minute - normally comfortable is 500 feet per minute.

Capn Bloggs
7th Feb 2017, 09:58
What he does before joining the approach doesn't seem particularly relevant,
It is very relevant when you are looking for traffic on Final as you're turning base! Would you be looking through the roof for traffic on final 2000ft above the normal slope? Bugsmashers can do what they like out in the boonies but at a CTAF aerodrome, they had better think "well there may be somebody else out there, I should be as normal as possible".

When were the rules changed to permit straight in approaches?
Many years ago.

Utradar
7th Feb 2017, 10:18
Andrewr,

11,300' at 10nm is not normal. That combined with minimal radio work is also not good airmanship. You seriously can't be defending this?

150kts = 2.5 nm/min = 4 min from 10,000' = 2500'/min...... Really?

Re straight in approaches can be done and is done all time Jepp ATC 6.7.6

Lead Balloon
7th Feb 2017, 10:40
11,300' at 10nm is not normal. That combined with minimal radio work is also not good airmanship. You seriously can't be defending this?

150kts = 2.5 nm/min = 4 min from 10,000' = 2500'/min...... Really? Don't go to YMRY. You might wet your pants.

The risk level at which you wet your pants is not an objective measure.

Re straight in approaches can be done and is done all time Jepp ATC 6.7.6.Jepps ain't the authority.

Utradar
7th Feb 2017, 10:42
Most of the rules in Australia have been a special kind of stupid for a long time, and fortunately the rules have little-to-no causal connection with safety outcomes.


I do agree to some extent

andrewr
7th Feb 2017, 10:43
11,300' at 10nm is not normal.

If you were conducting spin testing, how far away would you recommend going so you would not be spinning through altitudes likely to be used by RPT?

straight in approaches can be done and is done all time

I know, but my memory is that they were not always allowed. I was trying to remember when that changed. I would guess early 2000s, but that seems very recent so my memory may be faulty.

Capn Bloggs
7th Feb 2017, 11:19
If you were conducting spin testing, how far away would you recommend going so you would not be spinning through altitudes likely to be used by RPT?

It's not the place they were doing the testing, it was the approach they did afterward.

The risk level at which you wet your pants is not an objective measure.

Jepps ain't the authority.
More completely pointless codswallop. You really need to give the snipes and barbs a rest, LB. It really is pathetic that you continue to harp on about mandatory this and that verses recommended this and that. The only reason things are mandatory is because there are idiots around who have no idea about commonsense/don't care/deliberately disobey because they can't stand being told what they should say/do.

Utradar
7th Feb 2017, 20:00
The risk level at which you wet your pants is not an objective measure.

Don't be silly.

No, but the pucker factor has kept pilots alive for a long time. It's our internal risk assessment tool.

If pilots don't have good airmanship and disregard safety then they're putting themselves and others at risk. This is objective ok.

Lead Balloon
7th Feb 2017, 21:36
Don't be silly.

No, but the pucker factor has kept pilots alive for a long time. It's our internal risk assessment tool.

If pilots don't have good airmanship and disregard safety then they're putting themselves and others at risk. This is objective ok.

Well said.

My apologies.