737 intercepting LNAV while in HDG mode

[erjdriver1]

Let’s say you’re in HDG mode and ATC tells you to intercept LNAV at an angle.

Under certain situations I’ve seen on engaging LNAV, the plane go to a steeper intercept angle.

For example, I turn the plane towards a 30 deg intercept in HDG mode and then engage LNAV..the plane will sometimes go to 40 or even steeper intercept…not something the atc wants.

I know one criterion is that the plane wings have to be level before engaging LNAV. But sometimes even that doesn’t work.

is there something else out there…like distance from course before LNAV can be engaged etc.

[rudestuff]

ATC tells you to intercept LNAV at an angle?? Are you talking about vectors to an RNAV?

[erjdriver1]

Yes to be very specific..but any time going from HDG to LNAV with a reasonably shallow intercept angle. I.e 30 degrees

[Saugus]

What software version are you using? I use U13. I believe that within 3nm, if you engage LNAV, it will turn to capture the course. Outside of 3nm, and a 90 degree intercept or less, it will maintain your heading to intercept the course. Is that what you are seeing?

[ThrustAssymComp]

all your questions are answered in the cbt, fctm, fcom