Darwin Air Traffic Control

[RENURPP]

Would like to receive some answers from Darwin ATC's if possible.

Firstly 15/9/02 NOTAM indicates due lack of radar services that you are only allowed two aircraft on frequency??

What is the logic for this procedure.

[No Further Requirements]

To answer your question, in short, it's a risk mitigation thing.

Now, for a more detailed answer. Firstly, we are not blessed like most other capital city airports, and lack several radar feeds. The Tindal radar covers to about 30NM south of Darwin above 5000ft. So, if we have to turn the radar off for maintenance (which does have to happen periodically) we have to adopt non-radar or procedural control. This, obviously, is no walk in the park. Especially since controllers in Darwin hardly ever get to do it in anger (thankfully).

To keep current, we, just like pilots, have to do a certain number of hours per month in the position. We have to do 2 per month to remain current. There are about 15 radar controllers at Darwin, so that means at least 30hrs a month with the radar shut off so we can remain current (but not necessarily proficient - there is a difference). To get the most training out of the time without the radar, you would want to do it in the day when it is busy. So, at least one hour a day every day without the radar just to keep controllers current (and I highlight again, not proficient). Would industry accept this and the delays it causes? Not a chance.

So, the RAAF (through the ADF Directorate of Flying Safety) have allowed us to conduct LIMITED procedural control. That limit - two on frequency at any one time. Restrictive - yes. Safe - absolutely. If you like, we could do what they did a while ago and make the whole of Darwin's airspace (60NM radius of DN) a temporary restricted area, one aircraft at a time only allowed in there and only a tower service provided. Delay city!

To put it another way: you do a C310 endorsement 5 years ago. The closest you have been to a C310 since then is you saw one take off the other day. Would you feel comfotable flying a 4 hour night IFR leg though storms in the C310 tomorrow with no weather radar and an unreliable GPS? No. Would you feel Ok about taxiing it to the fuel bowser and back - yep. Pretty much the same for us. It is, as I said, a risk mitigation thing.

Don't know how well I have explained myself. If y'all have any questions, feel free to email me on my profile email.

Cheers,

NFR.

[RENURPP]

Thanks for that.

Do controllers at other airports have to carry out procedural controlling as well to remain current?

[No Further Requirements]

Most enrote control in Australia is done procedurally. Any of the major airports with dedicated approach sections have radar and there are none that I know of that switch it off to practice procedural. As I said though, just about all of them have more than one radar feed though, so the likelyhood of a multiple radar failure is low. Some Approach funtions are done procedurally from the tower in places like Alice Springs and Tamworth, so the controllers there are current in procedural approach. Most APP controllers (al in the in the RAAF anyway) are taught procedural approach, but it is not used very often. A 'just in case' thing. Cheers,

NFR.

[Spinnerhead]

Now theres a place where you can get really screwed over. Aircraft are tripping over each other trying to get out (or in) before the tower opens.

[TinPusher]

We used to run a procedural board beside the radar position and remain fairly proficient at procedural control without slowing the traffic too much, do you not do the same???

I've noted that Darwin gets bagged alot by some pilots. If you are turning the radar off when you need it most for 'training or currency' then it's no wonder really!

[Icarus2001]

Interesting analogy NFR.

Pilot's can and do use synthetic trainers and simulators to remain current without the"inconvenience" and cost of having to go flying. Why should ATC be any different? What is wrong with using an ATC sim to keep current?

[RENURPP]

The reason I asked the initial question is related to a flight I did on 15 sept. In defense of ATC it was late at night and not much traffic. The two mentioned below a B200 well ahead of us, he was on base as we were 30-40 miles, and a 767 taxiing as we were landing. Can't remember the exact time but pretty late.

I was inbound from Gove in a 146, another 146 was inbound direct from Cairns 30 nm behind approx. I was around 150nm Darwin which puts the other guy around 180 DN and he was told to carry out an orbit. That put him 70 nm behind and he was number two to us.

That just seems rediculous to me, 70 nm between aircraft???

This is the sort of thing that gives Darwin ATC a bad name.

If they can't properly resourse it they shouldn't be there.

[The Crimson Fruitbat]

RENURPP,

How long have you been flying into Darwin??

Two similar types inbound on the same route - If at same level, 20nm in trail spacing (with no closing speed) would have be worst case requirement that far out.

You can assume the traffic restrictions are there to protect you, the pilot and pax, and the staff who generally have lower local experience and local corporate knowledge (not necessarily less skilled!!) than their civil counterparts (they are transients in keeping with military requirements - posted in for a few years then out). Its not the controllers fault nor an indication of their abilities, its just the nature of the system and its better to be safe than sorry.

Darwin would probably have only about 2 or 3 guys (non-management, as in - line workers) with more than two to three years approach control experience controlling civil aeroplanes, its simply the way it is and will be to come (there are also people often leaving for civil ATC around the world as well as normal military posting cycles). On the other hand, if you fly into a civil controlled airport a controller on the other end with five years local experience is still relatively a "new guy". Guys/girls with 20+ years with the headset on in one set of sectors or terminal are regarded as nothing out of the ordinary (you often take a CUT in pay to go up to management so people who enjoy the job stay put). In the military, the game is about advancing your career as a military officer and meeting or exceeding the requirements to get promoted; the civil equivalent is about financial rewards, settling in to a community over a decade or three (locational stability) and simply controlling aeroplanes.

If memory serves me, Tin Pusher, who posted above, works a TCU in Godzone, betcha he has been there more than a "few" years, knows every nook and cranny in his airspace. If his radar failed or was shut down in the middle of the night for maintenance, odds on he would play it procedurally in without too much fuss (although probably with pulse quickening somewhat ;) )

[RENURPP]

We were not at the same level.
We were never 20 miles apart the minimum was 30 then increased to 70.

Whats the matter with a step descent?
The end result was the second aircraft 70 nm behind us and still having to go-around because ATC launched another aircraft off the non duty runway towards him. i.e. rwy 11, and couldn't let the inbound aircraft descend, resulting in him being toooo high and having to change runways at the last minute.

The rest of your psot simply supports my original question.

If the RAAF can't properly resourse it they shouldn't be there.

"It" being controllers and equipment.

[The Crimson Fruitbat]

Renurpp,

With a 20nm (or more) in-trail standard you don't need a step descent you are both good to come down (you don't need vertical separation since a "longitudinal" standard exists). In fact if you had more than 20nm you can have some closing speed, provided (from MATS 4.2.6.12):

a. separation is in excess of the minimum distance required;
b. distance checks are made at intervals not exceeding 15 minutes; and
c. when aircraft are cruising at levels not vertically separated, the closing speed is not greater than 35 KTS IAS or 0.06 M.

Further, once the leading aircraft is within 30nm of the airport this in-trail spacing can be reduced to 15nm; When the lead is within 20nm of the airport the spacing reduced to 10nm; and, When the lead is within 15nm of the airport, the separation can be down to 5nm. In all the 15/30, 10/20 and 5/15 standards the aircraft must be assigned vertical separated levels. These standards are useful when two aircraft are on descent and the lead is higher and you need to get it through the level of the following since it is likely to be the first on final approach.

Whats the matter with a step descent?
The end result was the second aircraft 70 nm behind us and still having to go-around because ATC launched another aircraft off the non duty runway towards him. i.e. rwy 11, and couldn't let the inbound aircraft descend, resulting in him being toooo high and having to change runways at the last minute.

As I have explained above that are enough standards available in the scenario you descibed so a step descent was not required. As for playing "runway roulette" without radar.....hmmmm :rolleyes:

[RENURPP]

Thanks for that info.

We were under radaR CONTROL UNTIL 30NM.

[The Crimson Fruitbat]

Coral,

Do we know each other?? You're not one of the AsA chaps surreptitiously tunnelling north east under the Pacific are you, in pursuit of more $$, less work and better skiing?? ;)

No aspersions intended to be cast on on the management and crew of YPDN ATC, just answering RENURPP's queries on whats available procedurally when two are inbound on the same track and the intrinsic difference between civil and military staff tenure.

Am I going to run into you one year at the Australia Day bar-b and cricket match in front of the lodge at Lake Louise?? :D

[the wizard of auz]

Well I hope you got ya sh it together by Friday as I will be flying into Darwin around then.
Cant miss me, I'll be the NO PLAN flight chasing a clearance.
Hey, whos up for Beers when I get there?. :D :D

[the wizard of auz]

Well I'm in Darwin and I got in alright..............even if I did take the wrong taxi way to the GA area (I was listening to the darwinite sitting beside me) and not one single offer to have a beer from you fella's. I thought you were all big guzzelers up here...................sheesh, I been guzling by me self. :D :D