C90 GTX Tutorial

[mokeiko 39]

Can anyone provide a tutorial for a simple flight and show me how to use the VNAV with the FMC. I am still having problems with the aircraft not following  the FMC ALT constraints. How about another tutorial without the FMC ALT constraints and just use the FMC NAV and I can control the ALT myself. Or better yet how do I fly this aircraft in general. At the moment I have ditched this in the hangar and flying something more simple like my PMDG aircraft (at least I know their VNAV works).

 

Sample flight: Kodiak to Anchorage

 

PADQ ODK SHUYA HOM AMOTT ELIAS PANC

 

Thanks for any help

[KenG 492]

 

 

VNAV does not work like a Rockwell-Collins Pro Line 21. Carenado completely made up a VNAV system and it works according to Carenado logic.

 

For Carenado's logic you input the altitude in the LEGS portion of the CDU (FMS). Use either the /xxxx i.e. /8000 for 8,000 feet or /FLxxx for Flight levels. Once the altitudes are in the CDU you must also set the altitude preselector for the altitude. You will also need to increase or decrease the rate of climb (vertical speed) using the pitch wheel to meet your vertical profile programmed in the CDU. Unlike the real Rockwell-Collins FMS3000, Carenado's version will not compute a rate of climb of climb/descent to meet the programmed vertical profile. VNAV is much more confusing in the Carenado version, due to lack of documentation then the actual Pro Line 21 (and that is saying allot!)

 

As far as NAV mode, that is fairly simple (other then NAV also bringing on the autopilot.) Turn the HDG knob to intercept the course and select NAV. Manual leg changes do not work (another feature Carenado choose to leave out) I have been able to trick the CDU into giving me a current leg, but it is a PITA. Thus on a Procedure HDG to course DP it is better just to go direct to a point (requests it from ATC.)

 

Not worth the time to do a video right now as I am sure there will be at least one if not a couple of patches to this aircraft. I doubt Carenado is going to change any of their logic for the avionics, but you never know.

[mokeiko 39]

Hi Ken,

 

Appreciate you taking the time. I will work on it more this evening.

 

Fly safe.

[markb 4]

Hey Ken,

 

Since you seem to understand how the GTX works vs how it's supposed to work maybe you could help me understand something. If I'm flying along on a Programmed FMC/VNAV flight with an ILS approach programmed how do I actually lock onto the localizer and glide slope? In my attempts the GTX won't let me activate the approach button and just flys the programmed route w/o grabbing the actual glide slope.

[Richard Sennett 2,499]

Hey Ken,

 

Since you seem to understand how the GTX works vs how it's supposed to work maybe you could help me understand something. If I'm flying along on a Programmed FMC/VNAV flight with an ILS approach programmed how do I actually lock onto the localizer and glide slope? In my attempts the GTX won't let me activate the approach button and just flys the programmed route w/o grabbing the actual glide slope.

 

Dont quote me on this but you have to be low enough or it wont grab GS - at least in carenado aircraft - something like 1,200 - 1,300 ft cant remember but see if that helps

[KenG 492]

The actual Pro Line 21 does an auto switch-over to the preset and the FMS will automatically tune the #1 VOR to the localizer frequency. Thus in the real airplane everything happens automatically. I haven't tried this in the Carenado aircraft yet, but I have a suspicion that they choose not to implement these features into their version. Thus I would suggest doing it the old fashioned way and tuning the localizer selecting LOC1 as the active navigation.  

[KenG 492]

I tried this and as expected the system does not work per the actual Pro Line 21. You have to use the 'old fashioned' method I listed which is to manually set the localizer in the NAV radio then switch it to active. You will also have to input the correct course. The autopilot wanders a bit and despite intercepting at a 30 degree intercept the FGS flew through the localizer and lagged the glideslope for nearly half of the procedure. I think this was also an issue with the Hawker so maybe the solution over there will work with the C90. 

[markb 4]

Ken,

 

Thanks for taking the time to sort that out, much appreciated. I will try it the way you described and hope I have some success with the approach.

[Luis Cortez 0]

 

 

 

VNAV does not work like a Rockwell-Collins Pro Line 21. Carenado completely made up a VNAV system and it works according to Carenado logic.

 

For Carenado's logic you input the altitude in the LEGS portion of the CDU (FMS). Use either the /xxxx i.e. /8000 for 8,000 feet or /FLxxx for Flight levels. Once the altitudes are in the CDU you must also set the altitude preselector for the altitude. You will also need to increase or decrease the rate of climb (vertical speed) using the pitch wheel to meet your vertical profile programmed in the CDU. Unlike the real Rockwell-Collins FMS3000, Carenado's version will not compute a rate of climb of climb/descent to meet the programmed vertical profile. VNAV is much more confusing in the Carenado version, due to lack of documentation then the actual Pro Line 21 (and that is saying allot!)

 

As far as NAV mode, that is fairly simple (other then NAV also bringing on the autopilot.) Turn the HDG knob to intercept the course and select NAV. Manual leg changes do not work (another feature Carenado choose to leave out) I have been able to trick the CDU into giving me a current leg, but it is a PITA. Thus on a Procedure HDG to course DP it is better just to go direct to a point (requests it from ATC.)

 

Not worth the time to do a video right now as I am sure there will be at least one if not a couple of patches to this aircraft. I doubt Carenado is going to change any of their logic for the avionics, but you never know.

 

 

Lol, what's the point of VNAV if you have to input a VS profile?!

[KenG 492]

Lol, what's the point of VNAV if you have to input a VS profile?!

 

Ask Carenado.

[WarpD 824]

Just a small note.. for the C90 with the Proline... the autopilot doesn't control climb rate with regards to VNAV. It only provides a magenta circle on the vertical speed display called the FMS VSR Advisory Pointer. It is the pilot's responsibility to control the aircraft's climb rate to accomplish the vertical speed required (VSR). For descents the autopilot will command appropriate vertical rates to comply with programmed altitude constraints.

[KenG 492]

Ed, thank you. I should have been more descriptive when I stated the FMS3000 "compute a rate of climb of climb/descent to meet the programmed vertical profile..." I did not mean to imply that the FMS will command the FGS to CLIMB. That is standard in all of the Pro Line 21 equipped King Airs.