Radar heading...or maybe track?

[Tha' what?]

Just a quick q for the controllers..

When instructed to fly a radar heading, the GPS/ very basic FMS in our old a/c will correct for drift and fly track. Can you just confirm to me that you expect us to fly a magnetic heading and not track?

Thanks.

[Nogbad the Bad]

You are expected to fly a magnetic heading

[This is a crisis]

Yip - magnetic heading please. Can make it very interesting if we both try and take the drift into consideration.

Only exception is if you are instructed to climb 'straight ahead' on departure. Then it's your turn to take the drift into consideration and track the extended centreline.

[BALIX]

As previously mentioned, a radar heading is the magnetic heading and not the track. It is amazing, however, that different aircraft/pilots can interpret this differently as on occasions it is necessary to apply a slight divergence to a radar heading to enable two aircraft to fly parallel tracks, even aircraft at the same level and presumably affected by the same wind.

Perhaps one day we will be allowed to allowed to use magnetic tracks rather than headings but no doubt ICAO will take years before making a decision.

[Bearcat]

jeez..it reminds me years ago when the airbuses came out, i used to fly with a capt who thought it hip to fly track/fpa mode. atc would give a heading and he'd fly the track....a lethal propositon. he was reported to the training system and he got roasted.......in FRA early this morning....two g/a's and two guys pulled out of the approach sequence....training going on? when we were leaving anew shift appeared to be on and everything was ching ching!!

[Lon More]

T-T's favourite hobbyhorse; the inability of many contro

Lonllers at Swanwick to be able to distinguish between track and headings; surely the triangle of velocities must still be taught as one of the basics of aerial navigation.

Lon More,

On the Sarf Coast

[Bern Oulli]

Yes, the triangle of velocities is still taught to ATC trainees. And I think I can speak for my colleagues if I say that I'll lay a pound to a pinch of sh!t all controllers at Swanwick know the difference between heading and track. What I don't understand is why anyone should think otherwise. What is the difficult bit in the phrase "Fly heading....."? Or "Turn left heading....."?

[Stinger]

FLY radar heading

Point taken Bern .... actually, since you mention it, in my case at least it is the 'FLY' bit that I find difficult.

Dontcha just dread the instruction, 'make your present heading a radar heading'. "Oh sh1t, does that mean we have to try to take some control of this this and stop it wandering all over the sky"?

[Timothy]

Why is it that we are quite often given a heading that is clearly pointed directly at a VOR (it may just be my imagination, but this mostly happens leaving the London area heading towards DVR)?

You can tell that the controller is pointing you at the VOR, because as the VOR QDM drifts off a little you are given a new heading to correct. (I must say that they are usually very good at getting the heading right.)

So the question is, if you want us to be pointing towards DVR why don't you just tell us and leave us to work it out?

Sometimes the same thing happens on a SID, when we are given radar headings that neatly fly the SID for us.

As ever, only curious

Will

[vintage ATCO]

WC, need to ensure you're locked on a heading so that radar separation can be applied (against the other one who is also locked on a heading.)

For all we know, you could wander all over the place!


VA

[Timothy]

So are you saying that "Fly Heading 120" is more "enforceable" than "Direct DVR"? Does "Direct DVR" not mean "Direct DVR"? Why should my a/p be better at maintaining a heading than keeping an HSI beam bar in the middle?

Will

[PPRuNe Radar]

WCollins

Another factor is the Required Navigational Performance (RNP) of the airspace. Certainly in BRNAV airspace in the UK at the moment it is RNP5 which means you can wander outside of track by up to 5 miles for 5% of the flight quite legitimately.

Whilst practical experience shows that this 'allowed' wandering rarely happens, basing 'radar' separation of 3 or 5 NM between aircraft each of which can in theory be anywhere on a 10NM wide swathe in congested skies is not a wise idea. Hence we cover our ar*es and yours by using assigned headings.

I'm not even sure that the TMAs such as London below the BRNAV airspace even have an RNP accuracy assigned, thus the margins for error could be even greater depending on what the pilot is using to navigate Again unlikely but the legislation and procedures always cover the worst case.

[rodan]

Remember, R-O-N* spells D.A.N.G.E.R.

(* Resume Own Navigation, for the pilots)

That's what I was taught anyway.

The reason we use headings is because that is what is required to ensure standard radar separation. I'm sure most controllers have had their fingers burnt by routing an aircraft 'direct' to somewhere, only to have it point to a position 10 miles north. I know I have.

[Bern Oulli]

Quite right Rodan. Any trainee controller who tries to separate two aircraft with one or both on "own nav" and not a lot of spare space is likely to get a copy of the Air Pilot dropped on him/her from a great height.

'make your present heading a radar heading'

This usually means that whatever you are heading at the moment looks good to me for whatever devious purpose I have in mind, now stay on it until I tell you otherwise.

Don't forget, if you need to deviate from a radar heading for some reason (e.g. dirty big CB in your 12 o'clock), ASK.

[Spitoon]

Getting fingers burnt

A few years back I did a little bit of vectoring on a departure to keep it out of the way of an inbound. Instead of turning pretty much due North immediately, I took the aircraft about 10 miles West before clearing it to resume own navigation direct to the first RP on the departure route. Rather than turning right and going in a straight line to the RP the aircraft almost made a 180 degree turn toward the overhead (and, rather worringly, straight at the next departure). After I sorted the immediate problem out, I queried what the pilot was doing he told me he was turning to intercept the departure track as quickly as possible. He was adamant that not only was this the correct thing to dobut that I should have known that that's what he would do.

I can't say whether this is common practice - I'm not going to fall for it again!! In the same situation these days days I'll either put an aircraft on a heading to where it's supposed to be going and when well out of the way of everything put it back on its own nav or keep it on a heading and transfer it on a heading.

Yes, it's more work. But I still don't understand which bit of direct is so difficult to understand!

[AirNoServicesAustralia]

On the point of giving headings rather than allowing the pilot to fly direct to the VOR, I have to say controllers generally work to the lowest common denominator.

That being that while most pilots under their own nav will hold a steady course there are some that get the wobbles. Whether that is due to scalloping on the edge of the VOR range and the aircraft nav being at fault, or whether it is a pilot problem is irrelevant. It is much safer and gives you peace of mind if both guys 6 NM abeam each other are locked on headings.

One point that I have to say though is I have seen ATC's who have as an example a low overflyer at say FL150 and a departing aircraft passing 8,000ft climbing through the other aircrafts level both locked on the same heading and then scratch their head when they look up to see the aircraft converging, and bag the pilots. Seems they forgot the winds can be very different when 7,000 ft apart.

[Lon More]

A.N.S.A. as an instructor in zn area environment I would not allow a trainee to let two a/c at, or crossing, levels to remain on own navigation. As an examiner, I would stop the checkout.

Many years ago, when NDBs and Fan Markers were still common on Airways, I was taught to intercept the centre line at an angle of 30 degrees when given own navigation, then proceed to the next RP. I suppose many of my generation would still do this unless specifically cleared direct.

[fourthreethree]

spitoon
Depends on the phraseology used.....the only circumstances that I'm aware of whereby the pilot would have been correct would be if you told him to "resume flight planned route" in which case he would fly the most direct way to his flight planned route.
However I assume you didnt say that and you told him "resume own navigation direct...." and that to me is as plain as night is dark that he should take up a direct track (not heading ) to the aforementioned waypoint.

Of course it might be the case as mentioned by Lon (check your pms by the way Lon ) that the pilot was an old gi...er I mean guy, and was following old procedures.

WCollins
The phraseology you mentioned will not be found in any manual, the correct way to say it is simply "continue present heading", and should stop the aircraft from deviating from his track for any reason, eg turn over a navaid, slight deviation due weather, a look at the coastline, whatever.....It means for the time the aircraft is locked on heading ATC is in control of the direction of flight, and we can therefore base separation on this.

[Timothy]

fourthreethree

I guess you mean "radar heading"? In which case it weren't me guv...I know that that is no longer part of the lingo, like "recleared 270"

Generally, this has been very informative, thank you. I totally understand the situation (though I still don't know why ANSA thinks that a pilot who cannot track a VOR accurately will be able to maintain a heading accurately )

Will

[Roger Dodge]

What's all this 'RADAR' Heading anyway???

Surely 'Fly Heading' or 'turn left/right heading' is fairly understandable?? It would certainly negate the question that started this thread!!

I'm sure that the phrase 'Radar Heading' doesn't actually exist in the good book anyway