RWY HDG ? or RWY TRK

[MD83FO]

I fly the airbus 320, (on a fly rwy heading clearance) this aircraft is defaulted to fly the rwy track on initial climb, we can preselect the rwy heading prior to departure but it seems much more nominal to me to fly exaclty over the extended centerline in track mode.
my question is: doesnt it reduce work load on the controller to have the pilot fly rwy track so crosswind is taken care of ? at least on the airbus aircraft for the purpose of being consistent with the defaulted automation of the aircraft.
i hope my question was clear, english is my second language.
cheers!

[Over+Out]

It just means we want you to fly straight ahead and not turn on any SID tracks. It does not really matter if it is a track or a heading.

[spekesoftly]

It just means we want you to fly straight ahead Which is why, in the UK at least, the recommended phraseology is:-

"After departure climb straight ahead ............."

It does not really matter if it is a track or a heading. I disagree. If there's a significant cross-wind then the difference between track made good and heading could be considerable, and if separation is consequently eroded is will matter! :hmm:

[TopBunk]

In the USA you must fly the heading (ie no wind correction), it is not optional.

[spekesoftly]

National differences obviously don't help, and partly explain why this subject crops up so frequently. I'm not suggesting that one method is better than another, but that standardisation is the key.

[Pera]

Fly the instruction you are given. No need to make it complicated.

doesnt it reduce work load on the controller to have the pilot fly rwy track so crosswind is taken care of

In this instance it won't make any difference to the workload.

[radarman]

This old chestnut again! As ever, different people have different ideas about the phraseology and how it should be interpreted. You can please some of the people all the time, all the people some of the time, etc etc etc. But even if every controller world-wide agreed on what they meant and how it should be phrased, it would count for nothing if, as MD83FO has pointed out, the aircraft avionics designers have built in a default that does not agree with ATC requirements. We have this problem when doing surveillance radar approaches with A320's. The ATC requirement is to provide headings, but the Airbus default for flying non-precision approaches is to fly track. This can lead to discrepancies of up to ten degrees, which is not very helpful when you are trying to line the aircraft up with the runway.

[Ivor_Novello]

The ATC requirement is to provide headings, but the Airbus default for flying non-precision approaches is to fly track

I'm no aircraft expert, but I think the Airbus (like all aircraft) will fly a track when in LNAV mode, and a heading when the Heading mode is selected...

The Airbus has a HDG/TRK push/pull knob but it can still fly a heading mode like every other aircraft. Wouldn't it be a bit useless if it could only fly track ??? What you gonna do at high altitude when giving headings in a 90kts crosswind ?

[radarman]

Ivor,

I'm no expert on aeroplanes either. All I know is that on about 75% of our A320 approaches the pilots announce they will be flying 'Track'. We usually check with those that don't pre-notify, and the vast majority request 'track' instead of 'heading'. I questioned a ZB pilot on this once, and he said that Airbus SOP's require non-precision approaches to be flown in 'track' mode.

Going back to the original thread, I rather think that regardless of how explicit the ATC instruction, the aircraft's avionic software may result in the aircraft flying something other than what the controller intended. You would need to be an expert in every manufacturer's FMS software to know exactly what the aircraft will fly.

[Diaz]

If I'm not mistaken, A320's will fly in 'track', as they are usually required to fly the descent mode in FlightPathAngle, not V/S, to access FPA, they push a button that also makes the heading knob into a track- designed specifically for non-precision approaches.

[G-SPOTs Lost]

"Fly runway heading" hdg bug centered on rwy numbers, hdg mode selected on departure - AP engaged

"Fly straight ahead" hdg bug centered on rwy numbers, through when gear and flap up divide x wind by two and turn hdg bug into wind by that amount, probably have the back course displayed for orientation - AP engaged

Worked for years, you will find some people :ugh: want to create a virtual waypoint 10 miles out on the extended centreline and fly it, head down trying to program this imminently before departure is just folly... ever seen the AA video children of the magenta.....

Invariably its only straight ahead for a minute or two until seperation is achieved

[Torque2]

There seems to be some confusion here. Yes the airbus can be flown in either heading and vertical speed mode or track and flightpath angle mode by pressing a button.

Normal navigation mode is heading and vertical speed.

For pilot interpreted non precision approaches where tracking is required from a beacon of some sort then track and flightpath angle is used (bird on mode)which simplifies the approach by automatically applying the drift correction and automatically correcting the descent angle selected for adjustments in airspeed so that if a 3 degree descent path is selected then you can vary your flap and speed selections at will and still maintain your descent angle.

This does present a problem if doing an SRA. The radar controller would like the airbus pilot to fly headings, no problem, but at the descent point the pilot would like to have the 'track and flightpath angle mode' purely for the descent angle feature because that takes out the requirement to keep on top of checking the ROD/VSI and adjust for varying speeds/configuration, but you cannot have heading mode selected along with flightpath angle.

Now, it is quite possible to fly the SRA in the basic mode of heading and vertical speed, it just needs some pilot input and a check of the required ROD versus groundspeed but it seems to contravene the airbus methodology and possibly outside the acceptable norm for some.

The SOP versus ATC requirement seems to be cropping up a lot lately! :ok:

[cleard4tkof]

When you airborn and call Departure, you will always get headings to fly. That's why it is why it is called "maintain runway heading". Even on arrival you get vectored in HEADINGS.

[Ivor_Novello]

Now, it is quite possible to fly the SRA in the basic mode of heading and vertical speed, it just needs some pilot input and a check of the required ROD versus groundspeed but it seems to contravene the airbus methodology and possibly outside the acceptable norm for some.


Are you guys not allowed to touch the stick anymore ? ;)

[ock1f]

We have been told that runway hdg is just that-it might not be straight line out from the runway in a crosswind. If we want an aircraft to fly the extended centerline then our instruction must be 'track extended runway centerline' followed by the rest of the clearance/climbout instructions.

Wearing my other hat i have noticed that when paralleling aircraft x number of miles apart both can report hdg's up to 15+ degress apart even tho both are tracking parallel. When both are asked to confirm magnetic heading one is invariably in trk mode.

Over and out

[radarman]

Torque2 and ock1f confirm what I have said for a number of years. Aircraft and their systems are getting streetes ahead of ATC in their accuracy and complexity. ATC and avionics/airframe designers are not singing to the same tune, leading to a growing mis-match between ATC requirements and what the aeroplane can actually do. Pilots increasingly have to interpret and convert controllers' verbal instructions into an input acceptable by the computers that fly the aeroplane. Hence the confusion that peppers PPRuNe threads.

[This is a crisis]

This topic has cropped up so many times.

In the UK at least you should never be told to 'fly runway heading' - there is no such standard phrase. You are told to 'climb straight ahead', 'track extended centreline' or 'fly heading xxx'.

Most of the time it is used to provide separation from traffic being vectored downwind and therefore, as has been previuously said, in conditions of extreme crosswind, the difference between track and heading is very important.

[aussiegal]

In OZ, if you cancel the departure SID and it's daytime and visual you get given RWY HDG visual, if it's IMC and/or night and the acft can't take the departure SID or for ATC reasons (generally tfc and wanting to get you away asap) we'll cancel the SID and give RWY TRK xxx degrees.