Fly heading or ground track?

Velocity173 said:
Sure, it takes maybe 10 mins to gauge the winds on position. Point is, they know the winds, and if everyone is doing the same thing (flying headings) it keeps things predictable. Plus, it's easier flying a heading than a track anyway.
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I've wondered if you normally take groundspeed into account when issuing headings. Two airplanes on identical headings in a 30 Kt direct crosswind will be on significantly different ground tracks if one is going 80 Kt and the other is doing 160.

I also wonder what ATC expects for an answer when they ask "What's your heading to XYZ" since there's no practical way for me to answer that unless I'm already on that heading but I can easily determine the initial ground track (course) along the GCR to that point. I usually just respond with "My course would be nnn degrees". Of course if the difference is less than 10° ATC probably doesn't really care about it but in stiff winds the difference can easily exceed that.
 
Henning said:
Yes, words and their meanings, that is what this thread is about. Accurate semantics are somewhat important in technical endeavors.
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It's not semantics. Your heading is the direction the nose of your plane is pointed towards...ie; what shows up on the heading indicator. When ATC tells you to fly a heading you point your nose at that heading. Period.

Hilarious, I can't believe we're on what, page 4 of this already? Jeez...:yikes:
 
kenjr said:
It's not semantics. Your heading is the direction the nose of your plane is pointed towards...ie; what shows up on the heading indicator. When ATC tells you to fly a heading you point your nose at that heading. Period.

Hilarious, I can't believe we're on what, page 4 of this already? Jeez...:yikes:
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Correct, my question was "Which heading?" as there are three distinct recognized and defined headings to choose from; that is semantics. The difference between heading and course (heading corrected for set and drift) is again an issue of semantics.
 
gismo said:
I've wondered if you normally take groundspeed into account when issuing headings. Two airplanes on identical headings in a 30 Kt direct crosswind will be on significantly different ground tracks if one is going 80 Kt and the other is doing 160.
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I assume they do, since the headings given to planes going 60k and those going 500k are usually pretty close to correct from the get-go.

But they are human. My Sky Arrow gets off the ground in a few hundred feet and climbs about 65k, very steeply into a headwind. Yet leaving McGhee Tyson in Knoxville, I've been assigned "Runway heading". But with a right crosswind on 5R that could easily drift me over 5L by midfield, even before I've been advised to contact departure.

Since "Runway heading" means exactly that, I have been known to advise them I'll need more of an easterly heading to avoid drifting over another active runway. Just makes them aware of the possible conflict. I think the usual response is an expedited switch to departure, which immediately gives a more easterly heading.

I think it's just working together to anticipate "gotchas" brought about by unusual circumstance. Without needing to violate an ATC instruction.
 
Henning said:
Understood, but to fly a 020 magnetic heading by reference to the compass, you have to first apply the deviation correction listed on the compass correction card unique to that airplane.
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Absolutely. As you do when setting a DG.
 
Jmcmanna said:
You would have to talk to the QC manager here about that.
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At the same facility where management requires controllers to provide air traffic control service contrary to the procedures in Order JO 7110.65 Air Traffic Control? I'm confident that would be a waste of my time.
 
gismo said:
I also wonder what ATC expects for an answer when they ask "What's your heading to XYZ" since there's no practical way for me to answer that unless I'm already on that heading but I can easily determine the initial ground track (course) along the GCR to that point. I usually just respond with "My course would be nnn degrees". Of course if the difference is less than 10° ATC probably doesn't really care about it but in stiff winds the difference can easily exceed that.
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That's a good answer. IME, when controllers state, "say your on-course heading", or something similar, they want to know your course. They want to know what your track would be if you were told to proceed on course.
 
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Can someone give me a heading to get out of this thread? ;)
 
FastEddieB said:
I assume they do, since the headings given to planes going 60k and those going 500k are usually pretty close to correct from the get-go.

But they are human. My Sky Arrow gets off the ground in a few hundred feet and climbs about 65k, very steeply into a headwind. Yet leaving McGhee Tyson in Knoxville, I've been assigned "Runway heading". But with a right crosswind on 5R that could easily drift me over 5L by midfield, even before I've been advised to contact departure.

Since "Runway heading" means exactly that, I have been known to advise them I'll need more of an easterly heading to avoid drifting over another active runway. Just makes them aware of the possible conflict. I think the usual response is an expedited switch to departure, which immediately gives a more easterly heading.

I think it's just working together to anticipate "gotchas" brought about by unusual circumstance. Without needing to violate an ATC instruction.
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Instruction I'm given is "fly runway heading". Which to me means to continue out on the extended centerline course of the runway, regardless of which way the aircrafts nose points once I'm in the air.
 
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Dwayne said:
Instruction I'm given is "fly runway heading". Which to me means to continue out on the course of the runway, regardless of which way the aircrafts nose points once I'm in the air.
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I think "fly runway heading" means exactly what it says.

Departing RWY 5 means heading 050°, not applying a wind correction angle to maintain runway centerline, something difficult to do departing into IMC - though a lot easier now than it used to be.

If the instruction means something else, I'd like to see a source so I can change my understanding.

Just Googled and found this:

http://bruceair.wordpress.com/2012/11/01/fly-runway-heading/

Let me digest it later and reconsider.
 
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FastEddieB said:
I think "fly runway heading" means exactly what it says.

Departing RWY 5 means heading 050°, not applying a wind correction angle to maintain runway centerline, something difficult to do departing into IMC - though a lot easier now than it used to be.

If the instruction means something else, I'd like to see a source so I can change my understanding.

Just Googled and found this:

http://bruceair.wordpress.com/2012/11/01/fly-runway-heading/

Let me digest it later and reconsider.
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I think it still says to fly the extended centerline of the runway. If the wind turns you, you apply whatever correction to maintain that extended runway centerline (heading).
 
Yes, you should fly "runway heading." But inside the airport boundary, you need to be careful not to let the airplane drift into the departure extension of a parallel runway. Boeing Field is a good example.

With a common SW wind, 13L is full of VFR traffic crabbing into the Xwind in the pattern. If you depart IFR from 13R and let the airplane drift left with runway heading, you are causing a collision hazard.

With a strong Xwind at BFI you should follow the runway extension for 500' then transition to actual runway heading.
 
"Fly runway heading" is no different than ATC saying "fly heading" while airborne. You fly the heading not a track.

I know it seems odd in today's world of GPS proliferation but the system still operates from decades old rules. The system is still designed for the least equipped aircraft. Think back 40 yrs ago. You wouldn't expect some pilot departing into IMC who's told to fly runway with his clearance to calculate some heading to get a track when they're / U.
 
Dwayne said:
Instruction I'm given is "fly runway heading". Which to me means to continue out on the extended centerline course of the runway, regardless of which way the aircrafts nose points once I'm in the air.
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Negative. From the Pilot/Controller Glossary:


RUNWAY HEADING− The magnetic direction that corresponds with the runway centerline extended, not the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly or maintain the heading that corresponds with the extended centerline of the departure runway. Drift correction shall not be applied; e.g., Runway 4, actual magnetic heading of the runway centerline 044, fly 044.
 
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kgruber said:
Yes, you should fly "runway heading." But inside the airport boundary, you need to be careful not to let the airplane drift into the departure extension of a parallel runway. Boeing Field is a good example.

With a common SW wind, 13L is full of VFR traffic crabbing into the Xwind in the pattern. If you depart IFR from 13R and let the airplane drift left with runway heading, you are causing a collision hazard.

With a strong Xwind at BFI you should follow the runway extension for 500' then transition to actual runway heading.
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"Fly runway heading" means fly the heading corresponding to the actual magnetic azimuth of the runway, the pilot is not to correct for wind drift.
 
Dwayne said:
Instruction I'm given is "fly runway heading". Which to me means to continue out on the extended centerline course of the runway, regardless of which way the aircrafts nose points once I'm in the air.
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The Pilot/Controller Glossary has a definition of Runway Heading; it is what ATC expects you to do. I'll let you look it up.

Bob Gardner
 
Dwayne said:
I think it still says to fly the extended centerline of the runway. If the wind turns you, you apply whatever correction to maintain that extended runway centerline (heading).
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Wrong, per the Glossary definition.

Bob Gardner
 
bobmrg said:
The Pilot/Controller Glossary has a definition of Runway Heading; it is what ATC expects you to do. I'll let you look it up.

Bob Gardner
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Everything I read refers to "the EXTENDED centerline of the departure runway". That extended line is fixed and does not move. It's my heading when beginning my take off roll and it's the line I follow once off the departure end.
That's the only way I can remain on the "extended centerline" and I do whatever it takes to comply.

Re-reading Fast Eddie's link to the "Bruce Air" article http://bruceair.wordpress.com/2012/1...runway-heading supports this and even mentions applying wind correction when flying vfr.

The differences their referring to (Instrument Flying 1-42) are the small differences in the actual magnetic heading of the runway as compared to what's painted on them (the rounded off number).
 
Dwayne said:
Everything I read refers to "the EXTENDED centerline of the departure runway". That extended line is fixed and does not move. It's my heading when beginning my take off roll and it's the line I follow once off the departure end.
That's the only way I can remain on the "extended centerline" and I do whatever it takes to comply.
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The conclusion that you are not much of a reader is unavoidable.

From the Pilot/Controller Glossary:


RUNWAY HEADING− The magnetic direction that corresponds with the runway centerline extended, not the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly or maintain the heading that corresponds with the extended centerline of the departure runway. Drift correction shall not be applied; e.g., Runway 4, actual magnetic heading of the runway centerline 044, fly 044.
 
roncachamp said:
The conclusion that you are not much of a reader is unavoidable.

From the Pilot/Controller Glossary:


RUNWAY HEADING− The magnetic direction that corresponds with the runway centerline extended, not the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly or maintain the heading that corresponds with the extended centerline of the departure runway. Drift correction shall not be applied; e.g., Runway 4, actual magnetic heading of the runway centerline 044, fly 044.
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I read enough to tell me I must be on the "extended centerline of the runway" and that's where I'll be. "Heading" in the right direction.
 
Dwayne said:
I read enough to tell me I must be on the "extended centerline of the runway" and that's where I'll be. "Heading" in the right direction.
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I'm pretty sure what people have been trying to say is, the extended rwy heading is magnetic, and doesn't necessarily correspond to the number painted on it. When told "fly rwy heading", you point your DG at the same number the extended rwy points to, and go where the wind takes you.
 
Dwayne this is not rocket science. Fly runway heading means fly runway heading.
 
In addition, "runway heading" is not the same as "straight out" or "along the extended centerline" except in a no-crosswind condition.
 
Dwayne said:
Everything I read refers to "the EXTENDED centerline of the departure runway". That extended line is fixed and does not move. It's my heading when beginning my take off roll and it's the line I follow once off the departure end.
That's the only way I can remain on the "extended centerline" and I do whatever it takes to comply..
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Nobody told you to fly "The extended runway centerline" they told you to fly "runway heading" which is what you see on your compass when you are aligned with the runway for take off.

So given that we understand the term "heading" from the pilot's perspective to mean only one thing and that being the direction the nose is pointed let's say you are departing on runway 28, the surface wind is 310@15G22 and you don't know what it is at 500 feet and you are instructed to fly runway heading on departure:

Quickly, tell us what your compass is going to read as you depart? :dunno:
 
Dwayne said:
I read enough to tell me I must be on the "extended centerline of the runway" and that's where I'll be. "Heading" in the right direction.
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Then your reading comprehension needs to be improved and you need to read the entirety of the definition, it specifically states that you NOT apply a correction, but fly the actual magnetic heading that you lined up on, that means if there is a crosswind you immediately depart the runway's extended centerline.
 
Matthew said:
I'm pretty sure what people have been trying to say is, the extended rwy heading is magnetic, and doesn't necessarily correspond to the number painted on it. When told "fly rwy heading", you point your DG at the same number the extended rwy points to, and go where the wind takes you.
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Not only does the heading heading not necessarily represent the painted numbers, but the track does not necessarily represent the actual heading.
 
Henning said:
Not only does the heading heading not necessarily represent the painted numbers, but the track does not necessarily represent the actual heading.
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I was trying to keep it simple. But yes, you need to separate your world from what's on the ground to what's on your DG.
 
Dwayne said:
I read enough to tell me I must be on the "extended centerline of the runway" and that's where I'll be. "Heading" in the right direction.
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It is really, really, really hard to believe that you seriously just wrote that.

Come on now... Don't make it that easy for folks to pick on you.
 
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