Hi,

 

A strange question....what is the difference between course and heading?

I learnt that there were 2 types of course:

- One with a VOR or a LOC

- The "route" over the ground.

A HDG is where the aircraft is pointing.

 

So when we enter HDG 30, it just means that the nose of the plane should be pointing 30°? But it means that the plane can be flying in another direction than HDG 30° over the ground???????

 

Dangerous!

 

Thanks to help!

MUST CONSIDER WIND DIRECTION AND SPEED. DO SOME RESEARCH ON THE FOLLOWING: TRUE COURSE, TRUE HEADING, MAGNETIC COURSE,MAGNETIC HEADING. 

Hmmm....thanks.

 

Magnetic HDG = Angle between magnetic north and your HDG

 

Magnetic CRS = Angle between magnetic north and your CRS

 

True HDG = Angle between true North and your HDG

 

True CRS = Angle between true north and your CRS.

 

If there is wind, the CRS of the aircraft can change . If you enter a HDG, it will point to that HDG but if there is wind, CRS is not equal to HDG. Isn't it dangerous or am I missing something? Basically thr plane is no more going where it should!!!

 

Thanks

It isn't dangerous, although I can see where it might seem so if you aren't familiar with it.

 

The difference between heading and course that you see while in cruise is due to your wind correction angle. When you fly a constant heading, the nose of the airplane stays pointed in the same direction, but the actual track of the airplane across the ground can be altered by wind. So if you want to travel along a straight line (radial) on a heading of 270, and the wind is from 340, you will actually end up flying a HEADING of greater than 270 (probably close to 277 if my mental math is somewhat accurate). This heading will compensate for the wind that is blowing you "off course" so to speak. The nose of the airplane will be to the right of course, but the airplane will be tracking on course of 270.

 

 

Make sense?

adding to the excellent answer above.......

 

Any flightplan you fly, you will be expected to fly as a magnetic track(or Course). If you are hand flying, you will need to adjust for the wind manually. If using a modern AP, it will do this automatically.

 

If you then are being vectored by ATC with magnetic headings, they will have factored in the wind.

 

So the aircraft is always going where it should.

Hmmmm....yes makes sense!

 

Read something about a triangle....

So if we enter in the FCU HDG 70, it will try to fly CRS 70?

 

Thanks

I should have said "if using a modern FMC, it will fly the magnetic track between two waypoints". The glareshield AP controls, when using HDG SEL, will give you the option to fly a HDG or a TRK.

Hmmmm.....

 

But the A/P in HDG selective mode will basically try to do this: CRS = HDG (but the HDG now, can be different.)

 

Do you agree?

Hmmmm.....

 

But the A/P in HDG selective mode will basically try to do this: CRS = HDG (but the HDG now, can be different.)

 

Do you agree?

 

No

 

HDG SEL will fly a HDG ...ie nose pointed at whatever degree magnetic you have dialed in. If there is wind you will be flying a different track to that heading.

 

There will be a selector on a modern AP to change the HDG SEL to fly a track. If you select that, you will be flying the magnetic track you have dialed in.

 

CRS does not = HDG.  CRS is a magnetic track to/from a VOR or ILS

But the A/P in HDG selective mode will basically try to do this: CRS = HDG

You lack basic understanding what is CRS and what is HDG. People suggested to you long time ago that you should get a sim and experiment and see what it does under different inputs instead you ask endless questions and I can tell you aren't learning anything.

Yes....Will answer this evening!

 

@ michal: I will get a sim and a book explaining basics for christmas!

 

Thanks

No

 

HDG SEL will fly a HDG ...ie nose pointed at whatever degree magnetic you have dialed in. If there is wind you will be flying a different track to that heading.

 

There will be a selector on a modern AP to change the HDG SEL to fly a track. If you select that, you will be flying the magnetic track you have dialed in.

 

CRS does not = HDG. CRS is a magnetic track to/from a VOR or ILS

Thanks a lot,

 

Ok....

 

1) In managed mode, the plane uses only tracks to fly. It doesn't use HDG, do you agree?

 

2) Wiki: " In an aircraft, to correct for these difference between "heading" and "course"a navigator uses the wind triangle."

 

Does the FMGC use the wind triangle in selective heading so that track = heading?

 

Thanks a lot,

A.Roy

 

 

1) In managed mode, the plane uses only tracks to fly. It doesn't use HDG, do you agree?

2) Wiki: " In an aircraft, to correct for these difference between "heading" and "course"a navigator uses the wind triangle."

Does the FMGC use the wind triangle in selective heading so that track = heading?

 

1. If by "managed mode" you mean a FMC/FMS LNAV navigation function....then the aircraft will fly tracks, not headings

 

2. The FMC has no need to use a wind triangle. The FMC has access to Satellite positioning and inertial navigation equipment. This tells it precisely where it is and what track it is flying.

 

If you are flying where there is crosswind then track will never = heading.

2. The FMC has no need to use a wind triangle.

I disagree, the AP/FD has to compute 'first guess' wind correction angle and for this it needs some basic trigonometry. Plus there is a ton of great-circle formulas that FMC must know how to compute so it is in fact quite loaded with all kinds of formulas.

Ok....thanks a lot....

 

1) So the track we enter on the FCU, is it the angle between the track and magnetic north?

 

2) Well...michal give another answer....

 

A simple question: In selective HDG mode, does the FMGC use the wind triangle to try to match HDG and TRAK?

 

Thanks