Lowering Class E between Melbourne and Cairns

[Roscoe]

A flight from Bankstown, Camden, or The Oaks to Orange under this proposal would be an impossibly dangerous exercise.

Who would want to sneak over Katoomba at 1500AGL in a Westerly wind over 15 kts?

It can be very rough in that area when there is very little wind.

This Proposal affects any flyer on the East coast wanting to fly anywhere west.

I just cannot understand the thinking behind this Proposal.

[Bennyboy320]

17 minutes ago, Roscoe said:

Who would want to sneak over Katoomba at 1500AGL in a Westerly wind over 15 kts?

It can be very rough in that area when there is very little wind.

Remember safety is paramount, declare a PAN & climb as required, you & the authorities have to remain FLEXIBLE.

[Garfly]

4 minutes ago, Bennyboy320 said:

Remember safety is paramount, declare a PAN & climb as required, you & the authorities have to remain FLEXIBLE.

Like at Coffs.

[Roscoe]

Is anyone aware of AOPAs position on this issue?

[RFguy]

dual - VHF- Well it would have to be redundancy, not functionality.

Gary says : "But then, you can't have your two ADSB-out devices both transmitting at once so maybe you have to downgrade your proper transponder."

A: You can have a Mode S transponder and a Skyecho. (remember Mode S does not included extended squitter /ADSB )- Mode S-ES is an extension .
But you CANNOT have a Mode S-ES and a Skyecho (also transmitting ADSB ES packets). they will fight.

 

In that case you have your Mode S-ES doing its thing  and use the Skyecho as RECEIVE only.

 

-glen

 

 

 

Edited February 12, 2021 by RFguy

[RFguy]

Thinking how I could give ASA indigestion, and also something that needs reolution , I have written to ASA :

-----------------------

This communication discusses the issues of hex codes for Mode S transponders with and without ES/ADSB capability, and simultaneously, being fitted with an EC device, such as a SkyEcho.

CASE NUMBER 1 :

In the case of a Mode S transponder being fitted (Mode S, not Mode S-ES- that is NO ADSB capability) AND an EC device being used (like a Skyecho) : Can these use the same hex code ?

The Mode S transponder will do its thing- be a transponder  and be active with SSR and TCAS systems.
The EC device will squitter out the DF18 ADSB bursts, also.  Occasionally, there may be a simultaneous transmission of both, but the chances of that are approx 0.2% when nearby an SSR.  That's fine.

Potential problem #1 :

According to the specs, the decoder should treat DF18 bursts as being from an EC device..
Somewhere in the decoder memory, there will be a common reference to a hex code , one received from the DF18 EC burst, the other from some other transponder burst.

DF18 is also used for TIS-B messages if CF=0. But the EC device will have CF=1. But this depends on the AA field (spec DO-260 section 2.2.3.2.1.3) . Will a listening decoder hear a DF18 with flags of no transponder capability , and then mark that hex code in the memory as not for interrogation ?  That would be a problem, because then, the system may not interrogate the Mode S transponder aboard until an all-call was generated, where that transponder would reply. 

Potential problem #2 : a nearby TCAS device in PASSIVE mode moving to ACTIVE mode (interrogation) - Will the DF18 bursts continuing to be transmitted  from the EC device potentially colliding, or generating timing ambiguities be a problem ?

This needs resolution.  I would think two hex codes need to be used to cover all bases , one for the EC device, one for the ModeS transponder. Of course, if systems use the aircraft ID/callsign/flight ID instead of the hex code for referencing, that is another pool of problems.

Note, these problems dont occur with a Mode A/C and an EC device.

 

 

CASE NUMBER 2 :

This is a simple case, however I feel ASA need to be able to provide advice if asked :

In the case of a Mode-S- ES transponder device being fitted (that is a Mode S transponder also capable of  transmitting DF17 ADS-B bursts) AND  an EC device being used ( a SkyEcho, for example) -

In this case the SkyEcho EC device MUST be set to RECEIVE only , otherwise ADSB bursts will be transmitted from both devices, with slightly different data, collisions and also consuming valuable 1090 MHz slot time.

Is this ASA understanding ?

 

[Garfly]

 

Does this clarify #2?

 

From uAvionix  SkyEcho2 conditions of use awareness letter:

 

 "... it is acceptable to simultaneously operate a transponder and an EC device, but only if the transponder is not itself outputting ADS‐B position information.  Full details about the legal requirements for using EC devices can be found in CASA Civil Aviation Order (CAO) 20.18."

 

https://www.legislation.gov.au/Details/F2020L00693

[RFguy]

Hi Gary

yes certainly my #2 is answered.  That was reasonably expected. my #1 is the thorny one.....

 

For paragraph 2 (b), an EC device must not be operated in transmitting mode:

(b)   concurrently with a Mode S transponder that is also transmitting ADS‑B."

[kgwilson]

If you have not read the RA-Aus response to this pathetic Airservices proposal I urge you to do so. The new CEO has really done his homework and I congratulate him on a very professional, accurate and pointed response. It is 11 pages long but well worth the time to grab a coffee, glass of wine or beer and read through it carefully. Find it HERE It is in pdf form so can be down loaded and stored in a directory or just read it on from the web site. What amazed me though was they actually got 2 members responding that they supported this dumb proposal so I reckon these must be Airservices employees or paid stooges.

[Kyle Communications]

I read that document and yes I think they have done a great job of telling ASA what a bunch of numpties they are

 

[RFguy]

but....

I think there was the opportunity for RA to disagree and  have some constructive input.  and RA didnt. 

 

I felt the response simply poo pooed any ideas at all.  RA just roadblocked everything . Not progressive.

...disappointing.

 

 

 

[jackc]

10 minutes ago, RFguy said:

but....

I think there was the opportunity for RA to disagree and  have some constructive input.  and RA didnt. 

 

I felt the response simply poo pooed any ideas at all.  RA just roadblocked everything . Not progressive.

...disappointing.

 

 

 

What else can you do when getting served a crap sandwich?

You sure ain’t gonna eat it !

Nor garnish it with condiments to make it taste better 🙂

[walrus]

RAA.....Bravo!

[jackc]

Considering the proposal under consideration, the RAA did well and hopefully a better outcome will be seen in the final result.......

[walrus]

RF guy, RAA and other organisations HAVE to reject this proposal out of hand or otherwise they are conceding Airservices the right to make arbitrary decisions. We are then reduced to just being supplicants pleading for a few crumbs from the table.

 

AsA should not have done any of this, but now they have been stupid enough to raise the issue, we are within our rights to request a holistic and risk management derived  National airspace strategy that reverses the *** sandwich they have been feeding Australian GA and RAA pilots for years.

 

If you have ever flown into LAX and had a window seat you will know what I mean.

 

Far too restrictive rules on access to controlled airspace and huge chunks reserved for the RAAF are just the beginning. The East coast of Australia is just a series of lethal and unnecessary road blocks to GA and RAA aircraft.

[RFguy]

Walrus . hmmm OK.

 

https://www.infrastructure.gov.au/aviation/atmpolicy/air_traffic_management_plan/chapter_2.aspx

 

What they are doing IS  in their brief.   If you want to be part of the solution you dont take your bat and ball and go home.   To have input to a outcome, you need to be  discussing ideas and options  to get their head head. Just coming out and saying its all sh1t is one way NOT to be included in the outcome.

 

yes I have flown in a window seat into LAX >100 times.

[Cosmick]

I have a mate who left Air Services 4 years ago so this has been brewing for a while. The mindset here is the same as Individual solar to increase renewables. Primary radar only has limited range and is very expensive to setup all over the country. Initially ASA considered it cheaper to subsidize Transponders/Grant for ALL users to be a much cheaper option so secondary radar could do the job. For some reason the subsidy option has stalled but as it was once considered may be a push in that direction may succeed.

[RFguy]

On transponders  mixing with sky echos :  I would suggest, at the moment to hold your horses before buying a lower end Mode S transponder (that is a mode S without the ADSB OUT) .

Everything I have dug in and read now suggests Mode S (or S-ES)   and Skyecho transmitting do not mix. IE the Skyecho must be set to receive only.  This suggests that the only time you can use the SKyEcho for ADSB-OUT (IE bursting your own position) is with a Mode A/C transponder only. 

This means if you are going to buy a Mode S,  and desire to have ADSB-OUT, you need to avoid the 2nd hand Mode S only transponders and buy a transponder with Mode S-ES / ADSB OUT - a 4500$ streey price.  The Skyecho will function as your ADSB-IN box .

Otherwise, keep your Mode A/C  and use the Skyecho as ADSB IN/OUT.

This is NOT official advice.  However... I have been made aware that in the industry spec DO260B, that the dual use of a Mode S transponder and another device transmitting ADSB-OUT is prohibited. (before I all the problems I put out yesterday  in my letter to ASA asking them ) . 
-glen
 

[kgwilson]

In my response I advised them that the only way forward was to keep Class E as is and subsidise ADSB as the UK CAA has done. Most the aircraft flying around from 1500 to 5000 feet won't even be seen by Airservices radar anyway so forcing installation of this outdated technology is just plain stupid.

[RFguy]

OK.

So would the C above coffs harbour  get changed to E so a RA VFR aircraft could transit below low level coastal cloud that lurks 4500+ ' ?

 

[kgwilson]

The proposed Airservices disaster does not include any change to the existing airspace approaches to any airports. Class C does not change. Class D changes to Class G as soon as the Tower shuts down at Coffs and others. A study done some 10 years ago concluded that there was inconclusive evidence that there were any real issues.

 

Two years ago in April 2019, Airservices  began the AMP with a plan to change class C over Coffs to Class E so ATC clearance would no longer be required but a transponder would be mandatory as it is in all Class E airspace. Nothing has happened so far. If it had been changed the Mooney crash on 21 September 2019 partly caused by ATCs refusal to allow access to class C even though there was no conflicting traffic may never have happened.

[RFguy]

(Class E over coffs habour - That formed part of my submission)
There are some FAQs coming out

 

They dont know the answer to this question- they say

"At this stage we do not see any potential safety issues of introducing airspace with a varying base of CTA, however, we are in the process of conducting an extensive safety program in line with our Safety Management System."

 

which means NFI !

 

 

"

How do Airservices expect pilots to measure the current ground level in order to calculate the 1500ft AGL?
 

"The use of AMSL becomes problematic with respect to terrain, when introduced below 8500 ft. 1500 ft AGL provides a standard that considers the height of uncharted obstacles and the minimum 1000 ft terrain clearance as per MOS Part 173.

Pilots and air traffic controllers will continue to operate and manage airspace using AMSL levels. The airspace design principles will be in AGL (as used widely for Class E airspace in the USA), however aircraft operations will continue to operate using AMSL.

At this stage we do not see any potential safety issues of introducing airspace with a varying base of CTA, however, we are in the process of conducting an extensive safety program in line with our Safety Management System."

 

Edited February 13, 2021 by RFguy

[kgwilson]

And in the USA that has no problems with class E, no radio or transponder (or licence or pilot certificate for part 103 FAR aircraft) is required at under 10,000 feet.

[Thruster88]

E - transponder = G. 

There is no point in having class E airspace unless all the aircraft flying in it have transponders.

[kgwilson]

Well it works in the US with transponders not required under 10,000 feet and they are the gold standard according to Airservices. Under 5000 feet you may have your transponder on but not be seen anyway. If the Class E base stays at 8,500 feet then I am not going to quibble over 1500 feet as we are a much flatter country than the US.

 

With a 3000 foot margin when crossing the great dividing range I don't have an issue when a good westerly is blowing. I do if I only have 1500 feet.