Question for controllers re: vectoring heading vs. course

[VNugget]

So we all know that all vectors are headings, and not courses, so you just let ATC worry about the wind correction.

Now... it seems that in the experimental community, there is a trend toward solid state digital equipment that displays your course, not heading, which would make it impossible to precisely comply with vectors.

So is that a big deal? How precise are your displays? How much effort do you put in estimating a correction? How much precision do you usually get from the pilot, after it's displayed? I'm not fully versed in the IFR systems yet, but it seems most vectors are to the nearest 10 degrees. A 10 knot crosswind component at 100 knots is a 6 degree correction, so most of the time it would be rounded to the given vector anyway.

Any thoughts on the matter would be appreciated.

 

[charter dog]

What if the heading is rounded the other way? In a strong crosswind your drift angle could easily be 30 or more degrees. Maybe it would be better to use the compass. As far as I can recall, it's required equipment. If a compass is no longer required for VFR certification, it's news to me! Even if it weren't required, I'd have one anyway. And yes, ATC expects the assigned heading to be flown unless otherwise specified.

Best,

 

[Hold West]

So we all know that all vectors are headings, and not courses, so you just let ATC worry about the wind correction.

Now... it seems that in the experimental community, there is a trend toward solid state digital equipment that displays your course, not heading, which would make it impossible to precisely comply with vectors.

How are they getting around FAR 91.205(b)(3), which says you need a "magnetic direction indicator"? I always interpreted that as a mag compass, and if nothing else you can fly headings off that.

So is that a big deal? How precise are your displays? How much effort do you put in estimating a correction? How much precision do you usually get from the pilot, after it's displayed? I'm not fully versed in the IFR systems yet, but it seems most vectors are to the nearest 10 degrees. A 10 knot crosswind component at 100 knots is a 6 degree correction, so most of the time it would be rounded to the given vector anyway.

Any thoughts on the matter would be appreciated.

Part of opening up a position is figuring out what the winds are doing, and so how to correct. Then when the time comes I'll brief my relief on what the winds are doing if they are out of the ordinary. Yes, most vectors are round 10 degrees, though it depnds on the situation. For example, one downwind I vector to a lot has a runway heading of 024 degrees, but the downwind heading varies from 195 to 205 usually. That one gets split to the nearest 5 dgrees, since we are trying to run right at minimum lateral separation from landing and departing traffic on one side, and terrain on the other.

Long range enroute vectors are usually to the nearest 5 degrees also.

Vectors for traffic are usually in whole 10 degree increments.

As far as "does it matter", I think everyone should be playing on the same field, since it may matter a lot, for example a vector to parallel traffic. If both aircraft are not on the same magnetic heading, then they might continue to converge, not the desired effect.

We're still kind of stuck with the lowest common denominator here. Wouldn't it be nice if everyone had advanced avionics, and we could get away from using the same nav reference that Chistopher Columbus used in 1492...

 

[sleddriver71]

Originally posted by Hold West

"We're still kind of stuck with the lowest common denominator here. Wouldn't it be nice if everyone had advanced avionics, and we could get away from using the same nav reference that Chistopher Columbus used in 1492..."

I totally agree with you. It would be nice if we could just use true instead of magnetic and not have to worry about magnetic variation or if the heading indicator agrees with the compass (which gets totally screwed up with windshield heat on). Some day...

 

[Lrjtcaptain]

Hold west is correct. Tell me one avionic manufacturer that still doesn't incorporate a digitil HSI into there software. Bottom line, if you cant fly HDG 090' only direct from point a to point b using gps, well, good luck flying IFR then, if you can't comply with hdg's for vectors you aren't flying anywhere!

 

[Hold West]

Hold west is correct. Tell me one avionic manufacturer that still doesn't incorporate a digitil HSI into there software. Bottom line, if you cant fly HDG 090' only direct from point a to point b using gps, well, good luck flying IFR then, if you can't comply with hdg's for vectors you aren't flying anywhere!

In fact, you can't even fly a number of IFR procedures, now that I think of it - there are many that specify a heading until an altitude or joining an arc or a radial.

 

[VNugget]

Well looks like I was wrong. I was just reading the vansairforce forums and someone made a reference to this issue and got me curious so I posted this, but then I looked at the Dynon website, one of the leading mfg'ers of EFIS 'lite' systems for experimental planes, and it says it has a magnetic heading reference, so this shouldn't be an issue.

 

[Say Again Over]

It would be nice if we could just use true instead of magnetic

No I don't think so, all the runways would have to be renamed, as far as whether your flying a track or a heading, doesn't really make a lot of difference does it, just a number.