16 hours ago, BrianW said:

I guess it’s something to keep in mind for those that like to reset their DG to the runway heading before takeoff.

That's a foolish procedure to begin with anyways. Plenty of runways out there, like at klax and kord, are numbered for convenience instead of accuracy to the nearest ten degrees.

Hence the need to check the actual runway heading on the charts - especially when setting up for an ILS

1 hour ago, KevinAu said:

That's a foolish procedure to begin with anyways. Plenty of runways out there, like at klax and kord, are numbered for convenience instead of accuracy to the nearest ten degrees.

You misunderstood me. I meant the actual published heading not just the rounded runway number.  That was the whole point of what I was trying to say, some publications may list the runway incorrectly based on a co-located navaid. In this example KBPI lists runway 31 as 312 degrees when it should be around 317.

1 hour ago, BrianW said:

You misunderstood me. I meant the actual published heading not just the rounded runway number.  That was the whole point of what I was trying to say, some publications may list the runway incorrectly based on a co-located navaid. In this example KBPI lists runway 31 as 312 degrees when it should be around 317.

Still kind of pointless to do that.  As pointed out about the discrepencies in published data, you are just as likely to introduce an error as you are to fixing one.  Just remember to set your dg to your mc.  That's all you have to do.  No need to overthink your flying. No one can fault you if you keep your dg updated to mc regularly since whatever inaccuracies inherent there, are understood and accepted by those charged with oversight.

Indeed - and further, I would suggest that it is a much better idea to ensure your DI is synchronised with the magnetic compass before lining up.

When you do line up, you can then cross check the runway numbers/expected heading with the DI. If the DI is not indicating what you think it ought to be this may be an indication that you are not where you thought you were!

If you are in the habit of simply setting the DI to the heading of the runway you think you are on every time you line up, you are setting yourself up for a runway misidentification incident.

4 hours ago, KevinAu said:

Still kind of pointless to do that.  As pointed out about the discrepencies in published data, you are just as likely to introduce an error as you are to fixing one.  Just remember to set your dg to your mc.  That's all you have to do.  No need to overthink your flying. No one can fault you if you keep your dg updated to mc regularly since whatever inaccuracies inherent there, are understood and accepted by those charged with oversight.

I understand what you’re saying and once airborne it’s usually the only way to correct for precession. However, I was taught during my instrument training to set the DG to the runway heading since it’s a known heading.  I use this known heading to also verify the MC.  The MC can sometimes be prone to errors from outside influences, and blindly setting the DG to the MC can also lead to discrepancies.  In either case you still need to know what the heading should be and the reason it's published on the charts.

 

3 hours ago, skelsey said:

If you are in the habit of simply setting the DI to the heading of the runway you think you are on every time you line up, you are setting yourself up for a runway misidentification incident.

Of course this isn’t the first time I’m setting the DG, I do it once after engine start to get it close, then again during runup since the gyros should be up to speed.  The runway check is just to eliminate any last minute precession.

Are any of the runway ILS's at KLAX offset, or are they all straight in approaches?

John

No. All are 251 or 071.