UNICOM - Worse than useless?

[Guest Fred Bear]

Just a little pic of ADS-B in action. This is a snap shot of Sydney/Western NSW area right now from here. Obviously you can narrow the radar screen down in your aircraft. Unlikely that if you are in Sydney you need to know what's going on in Orange when flying a rec aircraft. I imagine the inflight display would be something like a TCAS display.

 

 

 

[Guest High Plains Drifter]

Andy, is there a screen shot available somewhere of the ADSB display set to 100 metres or there abouts ?

 

HPD

 

 

[Guest pelorus32]

I think that we've got thread drift here...but never mind ;-)

 

The point is HPD that ADS-B out, as proposed, has NO screen in your cockpit. For that you need further functionality, more $$$.

 

Regards

 

Mike

 

 

[Guest High Plains Drifter]

The Billion dollar contract

 

For a short clip of Marin Blakey (FAA) telling enthusiastic pilots about ADSB

 

http://www.aero-news.net/index.cfm?ContentBlockID=1db5ff4f-7212-4783-ba84-5e9c0dda9818&

 

Key words to listen for -

 

- Billion dollar contract

 

- How the increased costs of mode C didnt affect GA aviation

 

HPD

 

 

[facthunter]

FAA & ADSB.

 

HPD, the pilots didn't seem very enthusiastic, & I thought the gist of it was, It's coming anyhow and get used to the idea. I have to say that I have no difficulty with its use in controlled airspace En -route. Even in controlled airspace you can be cleared for a visual approach,( if the pilot agrees,) and this can save time , and you maintain your own separation.

 

Mike, I am in no way critical of you for bringing this topic up. I will make one statement here. There is good science and there is the other science ,BAD science.

 

On another aspect, TCAS uses data from the other aircraft which is (I believe) covers more parameters than would be available from ADSB alone ,yet still relies on altitude change as the avoidance technique. Crews who tried to "finesse" the result by track change based on what the cockpit presentation showed, frequently put the aircraft into a collision situation. This is with trained crews and only involving ONE other aircraft. I would like to think that some of this technology could work in the circuit environment, but I think, at the moment, it's a complete furphy. Circuit procedures done with due attention to accuracy, give proper attention to a GOOD lookout, (this needs to be taught), is what you have going for you.

 

I've done go-rounds at capital city airports based on my eyes. If I had waited for instructions from ATC there would have been a couple of smouldering wrecks. Please accept that you have the responsibility of maintaining separation, as PIC. If you are operating and missing other traffic to any extent, you are operating on luck, and I'm a bit apprehensive with sharing the sky with you. I'm not saying that I don't make mistakes, but I hope by modifying my procedures, that with a lot more care and discipline, serious ones will be rare. Nev

 

 

[Guest Flyer40]

I'm curious Nev, what do you mean by good science and bad science, and precisely what what in this thread do you attribute to bad science?

 

 

[facthunter]

Bad science.

 

Flyer40.. It's material that purports to be fact, but is a lot of assumptions with just enough substance thrown in for it to run , if not thoroughly scrutinised. It can be based on a false premise. Essentially bad science is not science at all. These are my words, it's not an uncommon term. ( I have to state that I'm making a generalisation, not trying to accuse anyone of attempting to practice it on this forum, but there is a fair bit of it out there in the big world, even in aviation) Some people might call it snake oil. It's often used to sell things or ideas which may not do everything that you may be led to believe they will .Science is a discipline that in the pure form, invites being tested and refined/ modified, in the light of greater knowledge becoming available. It might be a bit ponderous, but in the long run, more reliable, and the base for true progress. My reference was in response to the FAA & ADSB presentation specifically (but I think the australian (airservices ?) one was more questionable in that respect. That's why I support the current RAAus response... Nev..

 

 

[BigPete]

Well said - facthunter - well said.

 

regards

 

 

[Mazda]

On the subject of see and avoid, the introduction of any third party makes this "alerted see and avoid" which is a completely different ball game. That is why a third party is a good idea.

 

The risk of collision is obviously greatly increased at or near airports at lower levels. The problem with ADS-B for GA aircraft is that it will be next to useless for collision avoidance in the circuit area. Firstly, as Nev said, most of us will only have ADS-B out anyway, not ADS-B in. Secondly, ADS-B in can only be picured on a screen, it can't have a voice alerting system like TCAS (due to patenting issues). This means pilots need to have their head in the cockpit! Not good in busy circuit areas. Two crew airline aircraft with TCAS can use that and keep their heads out of the cockpit while listening for TCAS alerts, and watching out for non-transponder equipped aircraft (or those who have forgotten to turn it on.) By the way, I've seen airline pilots forget to turn on the transponder so don't think a GA pilot won't. Plenty of airline pilots get the frequency wrong too, so I guess we all can.

 

As for collisions at Moorabbin (or even Bankstown) remember that is GAAP airspace. Guess who is responsible for separation in the air at GAAP aerodromes? It's the pilot, not the controller. The controller just issues a sequencing instruction. So it is an alerted see and avoid environment. Perhaps these accidents were a diffusion of responsibility issue, where the pilots stopped looking because they thought the controller was responsible for separation?

 

If people are not sure about UNICOMs, why not trial one at your local field and see how it goes?

 

 

[Yenn]

We have been known to talk to planes in the area by radio, if they appear to be in need of help due to the house looking as if it is in the middle of the strip. This is possibly not legal, but could be explained as a safety responsibility or best practice, to use a current buzz word.

 

 

[Guest browng]

We have been known to talk to planes in the area by radio, if they appear to be in need of help due to the house looking as if it is in the middle of the strip. This is possibly not legal, but could be explained as a safety responsibility or best practice, to use a current buzz word.

Indeed, and I also routinely adopt the American practice of alerting other aircraft in the circuit of their visibility or lack thereof, e.g. "Piper J3 Bravo Oscar X-ray, mid downwind 27 Right, two ahead visual". The other aircraft in the circuit then know that you can see them and safely separate yourself from them. I have also been usefully alerted to wind shear near the threshold by an aircraft on short finals when I was still three miles out. It is that kind of information that a UNICOM operator can provide. As long as you see this as information only, and not advice, I see no reason why UNICOM cannot provide a useful service. The problem only arises when the PIC uses that information as an excuse to relax his own visual situational awareness, even subconsciously. I have also been advised by a UNICOM operator of the duty runway, only to find on arriving that the wind while very light, had shifted, and that runway now had a slight quartering tailwind component that would be bad news for a vintage taildragger.

 

 

[facthunter]

acknowledgement.

 

Thank you, big Pete, I wonder at times. Nev..

 

 

[Matt]

A practice implemented at Point Cook a few years back due to high number of aircraft in circuit (up to 8 at times!) and one I adopt at all non controlled airfields is to identify yourself as "number #" when turning base and final. This allows me and the other pilots in the circuit to verify their sequence in the circuit.

 

Back to the topic though, in addition to "see and avoid" (not 100% effective), surely any additional information that can be provided which is relevant to you, other aircraft and the airspace around you can only be a good thing. I can't understand why any pilot would want to deny themselves the opportunity of having more information at hand to aid in decision making.

 

My 2.2c

 

Cheers,

 

Matt.

 

 

[Guest Andys@coffs]

Andy, is there a screen shot available somewhere of the ADSB display set to 100 metres or there abouts ?HPD

HPD

 

I dont know if there is or isnt.

 

At the end of the day its just presentation of data and the ADSB-IN display could be configured to display as much or as little as the PIC demands, while the display could be simple or complex the reality is that the ability to detect an iminent intercept remains undetered by display complexity, when an intercept is judged likely what ever is displayed could be changed to address avoidance. ie "CLIMB, TURN LEFT time to impact 10....9....8 etc"

 

For example the display could show a top down view, perhaps using colour to denote altitude differences which would be interesting, but in my view too much info, or perhaps just a top down view of your plane with others only showing when its calculated that there is a risk of intercept. perhaps a counter in one corner showing the aircraft for which a response has been recieved, so you know its working.

 

Now whether that is of use to you, like unicom will be a determination of returned value vs cost vs risk. The only difference being that for it to work as advertised by the "bad science" brigade we must all be fitted with, and using an ADSB out capability and thats the bit that sticks in my craw......doesnt mean to say that I dont find the evolution of the SSR interesting from a technology perspective. The bit about voice alerting..... thats just a bunch of BS, at the end of the day voice is only one of many possible solutions to arresting your concentration to get a vital message across.

 

Andy

 

 

[nomis]

Mazda,

 

TCAS is still very much head in the cockpit. The TCAS will call CLIMB/DESCEND. You then have to promptly and smoothly adjust your V/S to maintain your V/S pointer in an area displayed as green on your Primary Flight Display. The area you don't want to be in is displayed red. You cant just be heads out looking for the other traffic. The V/S called for can and does change quickly depending on how the other traffic responds. Everyone will still have a look out but you are flying your V/S by using the PFD in the cockpit. This is on the A330. Others might be slightly different.

 

Our TCAS is inhibited below 900'. You only get Traffic Advisories instead of Resolution Advisories that will tell you to climb or descend. Can't see how an RAA aircraft would benefit from either this or ADSB. Most people would be better off spending their money flying more often and having further training to make them a better pilot than spending it on gadgets. Currency and training will beat machines and electonics anytime, and thats coming from an Airbus pilot.

 

Anyway the most fun type of flying is the type Browng seems to do.

 

 

[Guest ozzie]

being a slow type, i freak about getting run into from behind. so for all it is worth i have fitted a small rear view mirror. worked for spitfire pilots.

 

ozzie

 

 

[Flyer]

Some thoughts.....

 

The worst way to enter a circuit is a straight in approach.

 

No chance of seeing anybody until it's almost too late..

 

The second worst way to enter is on a modified downwind.

 

You still potentially dont get to see the aircraft upwind and crosswind and what's happening on the ground.

 

The best way to enter the circuit is to overfly above circuit height, have a good look at what the windsock is doing and what aircraft are moving, let down on the dead side and join upwind or crosswind.

 

By overflying, you have had a look for yourself and taken responsibility for the safety of yourself, your passengers and your aircraft.

 

Any information gleaned from other pilots and/or a unicom is now a back up to what you have already seen and can be used or discarded as required.

 

Unicoms can be a great source of information but they do not absolve you from your responsibilities which is to ensure the safe passage of you and your aircraft.

 

regards

 

Phil

 

 

[youngmic]

Flyer,

 

Not sure I agree with straight in approaches being the worst, circuit and straight both have pro's and con's. The advantages of flying a less judgment required long stabilized approach can allow more time to scan the area ahead and along base.

 

But then an aircraft on base is more likely to be focusing their attention on the runway and some don't remember to look outside the circuit, particularly important when about to turn final. Consider how this might be relevant to the recent fatality.

 

Any aircraft conducting a circuit will have relative movement across your field of vision and it is this relative movement that generally alerts you to their presence.

 

Straight in is predicated on the use of radio and this aids separation with any other aircraft also conducting a straight in approach, however other aircraft on a straight in approach can be difficult to spot due to that lack of relative movement and small profile. Radio announcement of your distance on approach can also be a trap as correct procedure is to measure your position from the threshold, but nearly all VFR GPS's will be referencing the ARP, IFR aircraft possibly off one of the aids if present and some off the DME read out. Personally I would like to see distance on final referenced to the ARP as this requires little or no set up to establish, which is why most presently are.

 

Regards

 

Mick

 

 

[Yenn]

Personally I like straight in approaches and find height judgement easy that way, but I seldom use that approach as non radio aircraft in the circuit would not be expecting me. It is easy to see other traffic in the circuit apart from those on downwind and of course they will be the greatest conflict.

 

To overfly and let down on the dead side requires being at 2000' over the top to avoid the faster traffic doing a 1500' circuit and a let down of 1000' which covers quite an area of ground.

 

The US recommended way into the circuit is to join long downwind at about 45 deg. rather than doing a crosswind leg as is common here.

 

Probably the greatest danger in the circuit is those pilots who do such a big circuit that they are nearly in the next state, and then come in at 3 deg or less on final.

 

 

[youngmic]

The US recommended way into the circuit is to join long downwind at about 45 deg. rather than doing a crosswind leg as is common here.

That is also the oz way now.

 

Mick

 

 

[Guest High Plains Drifter]

.

 

My thoughts about the Marion Blakey clip (USA FAA) -

 

I thought she was arrogant and spoke down to her audience.

 

Blakey mentions mode C transponders - they are not mandatory OCTA.(as in Australia) the unknowing veiwer may think transponders have to be fitted to all aircraft.

 

The transponder argument she uses is irrelavent to somebody who only flys OCTA (simular to Australian RAAus pilots)

 

From the way Blakey spoke it appears the whole world will be useing the American ADSB system - I thought Australia will be useing a different system to the US ?, Or has she (FAA) decided what the world will use.

 

Lots and Lots and lots of money floating around, future avionics company directer-ships and well paid adviser rolls coming up for compliant FAA / Airservices people. ( perhaps thats just me being paraniod, after all we arnt talking about cardbord boxs here)

 

HPD

 

 

[Guest disperse]

so your driving down the road approaching a 4 way intersection. You know that you have right of way because the cross street has a stop sign. Do you charged through the intersection without any cares, or do you still use caution. Same as Ballistic chutes and seat belts ..........if you neglect caution just because of a new safety device, It might just hurt

 

 

[Guest browng]

The US recommended way into the circuit is to join long downwind at about 45 deg. rather than doing a crosswind leg as is common here.

Joining mid-downwind is indeed the most common practice in the USA (I also hold FAA ratings and have flown extensively there), but it is not universal, and has its limitations. Where you have a decent proportion of recreational operations, EAA types, vintage, etc, an overhead join is common in the USA. There are several reasons for this;

 

An aircraft is most visible when turning, ergo the more turns it makes in the circuit the more visible it is going to be, that is why the 'standard' radio calls are preferred at turning points in the circuit.

 

Many older types (like my J3), are solo'd from the rear, and consequently have limited forward visibility, turns give the PIC more opportunities to see and assess the situation. This is equally true of biplanes, even relatively modern ones like the Pitts.

 

A mid-downwind join can limit your chances to see and evaluate the windsock and signal square, not a big deal in a 172 or Bonanza, but very important in an aeroplane that likes to bite its own tail.

 

 

[vk3auu]

Unicoms and Parachutes are of similar utility in my book. Better to have an AFRU. At the very least it will talk back to you and you will know that you are on the right frequency and if it doesn't then you can assume one of two options. Either you are on the wrong frequency, or another aircraft has called in the last five minutes so you should be looking out anyway.

 

If the unicom operator is otherwise occupied, which can often be the case, then you won't get a reply, so that means you might as well not have one.

 

I do believe that radios should be mandatory but should be used sparingly. Some pilots call at every turning point but this can get real messy at a busy airport. Better to just call Inbound, Joining circuit and Turning Final. Just keep your eyes outside the cockpit and if you are flying a slow ultralight, just track a little left of centreline so that an overtaking aircraft who perhaps doesn't see you, won't clean you up.

 

David

 

 

[Guest browng]

....if you are flying a slow ultralight, just track a little left of centreline so that an overtaking aircraft who perhaps doesn't see you, won't clean you up.David

Nice idea, but in reality only the runway has a centerline, circuit legs can be as wide or as narrow as the pilot deems fit, ranging from the nice tight circuits of types like a Gyro, or a Pitts doing a curved approach, to half a mile out for the student in his 152 Spam Can. Forget the centerline, it doesn't exist. The best way to separate slow from fast traffic is by height. At YBOO we operate differential circuit heights for slow and fast traffic separated by 500'. We have Gyros, rag and tube Ultralights, Vintage, Trikes, and fast GA, all operating safely separated, both with and without radio. All it takes is a decent Ops manual and discipline.