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eagleflyer
4th Jul 2011, 12:08
Hi there!

Do you have DF equipment available in your approach or area unit and how do you use it? Our company wants to save money and will remove the direction finders shortly. I donīt like this...

ZOOKER
4th Jul 2011, 12:55
D/F is a fundamental tool of both approach and approach radar control, especially if you have a lot of VFR traffic. It is often the one that saves the day with alerting service/aircraft lost scenarios. We also used it on GMC to find out which a/c had the Tx button inadvertantly pressed.
We never used it on area, but our Distress and Diversion cells have comprehensive D/F coverage.
Ask yourself this:- Do the people who want to remove this kit hold any aviation licences?

FantomZorbin
4th Jul 2011, 13:13
D/F ... very useful for all of the above plus: Controlled Descent Through Cloud (CDTC), No compass/no gyro procedures and practice flame-out descents in the overhead. Aaah! those were the days!

aluminium persuader
4th Jul 2011, 15:00
Indispensible for the lovely QGH! :E

HEATHROW DIRECTOR
4th Jul 2011, 16:06
It was removed from the Heathrow ATC facilities many, many years ago unfortunately..

FragRad
4th Jul 2011, 17:33
Also just removed at Ronaldsway with the move to new control tower - shame, it was really useful, particularly if radar was off for any reason.

Vortex Issues
4th Jul 2011, 18:45
None of the 5 main London airport approach positions have it

Spitoon
4th Jul 2011, 18:58
Indispensible for the lovely QGH!VDFs are a bit tricky without it too! Are there any left??

To give a slightly more serious answer.....life moves on. If you're working in a known traffic environment with solid and reliable SSR, maybe even mode S, perhaps we can live without DF these days. Change the environment to that UK speciality of providing a service in a mix of class D and class E or G and i would say it's still a vital piece of kit to help to maintain situational awareness.

Theoretically, in Europe anyway, any unit that is removing a DF installation from its armoury will have to do a risk assessment and, if necessary, take mitigation measures on the change. I guess this should be available so you can see how much the DF contributes to the safety of the service and what is being done to mitigate any hazard resulting from its removal. :uhoh:

Tower Ranger
5th Jul 2011, 07:27
At one of my previous units we had a pretty amazing bit of kit from Rhode and Schwartz. Not only could you select any frequency you wanted for the DF but you could listen in as well.
I think the skills that many of us used back in the days before modern radar coverage have long since passed into history.

ZOOKER
5th Jul 2011, 08:54
Along with QDM,QDR,QTE and QUJ!

chevvron
5th Jul 2011, 09:13
Back in 2002/3 we had to fight to keep it when we moved to the new tower at Farnborough; we were successful; it's an essential tool when operating non SSR equipped traffic whether inside or outside CAS, and when an aircraft below SSR cover has a problem you can 'home' it towards you until you get radar contact. It certainly saved situations many times for me at Farnborough.

fireflybob
5th Jul 2011, 12:08
but maybe there's now more than 360 degrees in a circle?

just heard "your QDM to XXXX is 364 degrees"! - (twice!)

canard68
5th Jul 2011, 15:48
You could buy one of these for $300.
Radio DF DDF2020T - GLOBAL TSCM GROUP, INC. (http://www.kn2c.us/ddf2020/radio-df-ddf2020t/)

ATCO Fred
5th Jul 2011, 17:13
Back in 2002/3 we had to fight to keep it when we moved to the new tower at Farnborough; we were successful; it's an essential tool when operating non SSR equipped traffic whether inside or outside CAS, and when an aircraft below SSR cover has a problem you can 'home' it towards you until you get radar contact. It certainly saved situations many times for me at Farnborough.

To true Chevvron - absolutely essential when providing LARS / Radar services in Class G airspace: Enables rapid identification, and timely traffic information to others, on those non transponder equipped customers :eek: It's on our wish list for the install at TK :D

BuzzLightyear
5th Jul 2011, 17:17
I can understand the usefulness of all the old tools that we used to use. I even remember procedural area control....ah the cowsheds at the old college of knowledge....but with the advent of all the new tools like Mode S and good reliable SSR, maybe its not as important now in these here parts. Lets face it given the choice of a nice clean vector for an ILS or working your nads off for a SRA or PAR that has higher minima which would you prefer? Yes there's a lot of satisafaction in doing it the old way, but time moves on.

Wouldn't like to speak for the less developed areas of the world though...

eagleflyer
6th Jul 2011, 08:08
Thanks for your inputs! Iīve always thought DF enhances safety, having seen some situations that I would never have thought possible. E.g. instruction to acft A, readback by acft B with the callsign of ACFT A, the DF saved me.

Another one: ABC445 is expected to call, but itīs ABC455 that calls in a busy situation, about 100miles away. ABC455 was accidentally sent to this frequency and misidentified for ABC445. DF was U/S at the time, so ABC455 complied to the instructions and a lot of confusion was created.

chevvron
7th Jul 2011, 09:03
As an example:
Aircraft calls you up uncertain of position and short of fuel, but below radar cover. D/F shows you his bearing so you can advise him of sector safety altitude, and once you have established he is VMC or above safety altitude, you can give him a heading to steer towards you to bring him into radar cover. When he comes into radar cover, you can then identify him and vector him to a suitable airfield.
Shimples!

Helen49
7th Jul 2011, 17:29
D/F may be not so necessary at TMA airfields where most of the traffic is in the tram lines but almost essential at airfields with a lot of GA activity and in Cat G airspace.

Been saved many a time when when the bearing of an unexpected inbound indicated that it was in the climb out with one about to roll! As others have commented, useful when aircraft reporting downwind are actually more like base leg; location of aircraft on the ground etc etc.

Should be mandatory at ATC Units in uncontrolled airspace for my money!

ZOOKER
7th Jul 2011, 20:57
Years ago, there was an incident at an aerodrome in Class A airspace where a SVFR light a/c was cleared to transit the centre-line of the active R/W behind a departing jet. The light a/c actually passed underneath the airborne airliner and an airprox was filed by company aircrew, who were passengers in the rear of the jet. In the report, one of the criticisms of ATC was failure to use D/F information.

Tower Ranger
8th Jul 2011, 03:03
I think the salient part of that post is the first two words, "Years Ago".

Helen49
8th Jul 2011, 07:17
Tower Ranger

Years ago many airfields lacked sophisticated radar systems which may negate the need for D/F. There remain many such airfields today.

Tower Ranger
8th Jul 2011, 08:56
In the last 20 odd years I`ve worked at a few of them.

Captain Smithy
8th Jul 2011, 11:19
All of the Towered ATSU's in Scotland still have DF. Controllers like it as it's a very useful aid for keeping track of where everyone is. Don't understand why it would be removed - even though nowadays we have radar its still a useful aid. And there are stil many towered units outside of CAS with no radar feed.

Smithy

fireflybob
8th Jul 2011, 13:14
Also from the pilot's perspective, isn't DF the most basic way of doing a controlled descent through cloud?

All you need in the a/c is a radio (you don't even need modulation to give a trace - aka "speechless"), an ability to fly on instruments and a compass.

Recall the days when radar couldn't find us due weather clutter but we did get in off a VDF/QGH.

chevvron
14th Jul 2011, 15:07
While I was doing a PAR course at Shawbury, we were invited to 'assist' in the QGH trainer, and watching how a 'speechless, no compass, no gyro' QGH is done was incredible!!

Guest 112233
17th Jul 2011, 10:15
OK I'm no ATCO (Did try once) - There's an engineering principle at stake here - Often the simplist technology works well in unforseen circumstances - simple to use for both parties espcially under duress. - Keep those "Bean counters" away from your VDF sets & Ariels. Yes I have seen it in action.-

The technology is old, but forms a tool in the armoury that might be needed by a controller..

Sorry to intrude.

CAT III

2 sheds
17th Jul 2011, 11:09
Cat III

No need to apologise - you are spot on!

2 s