gtn 650xi auto bugging altitude on a gi 275

[7ZSTTto2]

i'm not even sure what the right terms to google for this would be, but does anyone know if it's possible to get an xi unit to automatically bug the altitude on a 275? i'm working on my instrument now and while most of the approaches have glide slopes, the occasional vor or loc has me wishing there were a way to autobug the step downs. is this possible?

 

[asicer]

i'm not even sure what the right terms to google for this would be, but does anyone know if it's possible to get an xi unit to automatically bug the altitude on a 275? i'm working on my instrument now and while most of the approaches have glide slopes, the occasional vor or loc has me wishing there were a way to autobug the step downs. is this possible?

If you have a GFC500, you can push the VNV button and have it fly step-downs for you prior to the FAF. Or you can use the FD bars and be its meat puppet. The GFC700/G1000 will display both the VPTH target alongside the bugged altitude, but I think the G5/GI275 is too small for that so it doesn't. You'll just have to glance over every now and then at the altitude on the GTN FPL screen.

 

[422Phil]

If you have a GFC500, you can push the VNV button and have it fly step-downs for you prior to the FAF. Or you can use the FD bars and be its meat puppet. The GFC700/G1000 will display both the VPTH target alongside the bugged altitude, but I think the G5/GI275 is too small for that so it doesn't. You'll just have to glance over every now and then at the altitude on the GTN FPL screen.

Asicer, if I’m cruising up at 6k and I’m on final leg headed toward the initial approach fix which is at 3k, do you press VNAV and it will begin a descent to the initial approach fix at 3k, or do you activate VNAV once you reach the initial app fix, and then it flies the step downs?

 

[asicer]

Asicer, if I’m cruising up at 6k and I’m on final leg headed toward the initial approach fix which is at 3k, do you press VNAV and it will begin a descent to the initial approach fix at 3k, or do you activate VNAV once you reach the initial app fix, and then it flies the step downs?

On the G1000/GFC700 if en route vertical navigation is populated in the FPL (which it automatically is when an approach is loaded), you're supposed to hit the VNAV button some range of time before Top Of Descent. I usually just wait for the Lady of the Box to exclaim "Vertical Track". This arms VNV/VPTH. You also need to set the bug to some altitude below the target altitude. Then, when you reach TOD the plane noses over and then flies the step downs to the FAF/FAC.

It's actually been some time since I've flown a GTN. I do remember that the logic is similar to the G1000, as is the GFC500 to the GFC700.

 

[wayneda40]

i'm not even sure what the right terms to google for this would be, but does anyone know if it's possible to get an xi unit to automatically bug the altitude on a 275? i'm working on my instrument now and while most of the approaches have glide slopes, the occasional vor or loc has me wishing there were a way to autobug the step downs. is this possible?

@7ZSTTto2 , normally the HDG and ALT bugs are managed by the autopilot, e.g. a GFC500. @asicer does a very nice job above explaining how the VNAV function works. Here's a 3-part video series on Modern Avionics and the Instrument Pilot that may also be of help.
Wayne

 

[7ZSTTto2]

thanks, all. no gfc 500 in my plane so I'll just make sure to keep the 650 on flight plan mode when i'm on step down approaches.

 

[midlifeflyer]

thanks, all. no gfc 500 in my plane so I'll just make sure to keep the 650 on flight plan mode when i'm on step down approaches.

Yep, the transfer of those altitudes to a PFD from a FMS is a function of autopilot capability.

In airplane where I don't have that, I do the same as you - display the flight plan rather than the map when flying an approach.