Excel/XLS - using VNAV for NPA
Thread Starter
Join Date: Oct 2008
Location: UK
Age: 44
Posts: 139
Likes: 0
Received 0 Likes
on
0 Posts
Excel/XLS - using VNAV for NPA
Hi People
Could a kind soul talk me through what needs to be done to use VNAV for an NPA, either VOR or NDB?
Our aircraft uses a UNS 1 FMS.
Currently what I'm doing for say a VOR is using APPR mode to maintain a more accurate track than just NAV. Dialling down the MDA and selecting VS mode prior to descent point and then at descent down we go! Both pilots are then monitoring the ROD to conform with the DME check altitudes.
I have been told by our training captain that we can use VNAV/FMS mode (ie. purple screen) providing we have the raw data needle overlaid as back up. Apparently this way both pilots can be in FMS mode but obviously still monitor the required ROD.
Would like to try this next time we're in VMC on approach.
Many thanks.
Could a kind soul talk me through what needs to be done to use VNAV for an NPA, either VOR or NDB?
Our aircraft uses a UNS 1 FMS.
Currently what I'm doing for say a VOR is using APPR mode to maintain a more accurate track than just NAV. Dialling down the MDA and selecting VS mode prior to descent point and then at descent down we go! Both pilots are then monitoring the ROD to conform with the DME check altitudes.
I have been told by our training captain that we can use VNAV/FMS mode (ie. purple screen) providing we have the raw data needle overlaid as back up. Apparently this way both pilots can be in FMS mode but obviously still monitor the required ROD.
Would like to try this next time we're in VMC on approach.
Many thanks.
Guest
Join Date: Apr 2003
Posts: 876
Likes: 0
Received 0 Likes
on
0 Posts
Do you not mean LNAV, which is would be why you say
?
May sound like egg sucking teaching but VNAV is for vertical. The needles that are available during an NPA are for "Lateral" guidance.
Some operators use VNAV/LNAV though but not NJE and its Excels. On the other hand, LNAV overlaid is accepted.
providing we have the raw data needle overlaid as back up.
May sound like egg sucking teaching but VNAV is for vertical. The needles that are available during an NPA are for "Lateral" guidance.
Some operators use VNAV/LNAV though but not NJE and its Excels. On the other hand, LNAV overlaid is accepted.
Last edited by PPRuNeUser0215; 5th Mar 2009 at 12:29.
Thread Starter
Join Date: Oct 2008
Location: UK
Age: 44
Posts: 139
Likes: 0
Received 0 Likes
on
0 Posts
No I mean VNAV which effectively means it's similar to precision app in that the jet descends itself following a VNAV profile. As to whether he also meant LNAV to be used instead of APPR mode, I don't know??? 
Join Date: Nov 2002
Location: UK
Posts: 138
Likes: 0
Received 0 Likes
on
0 Posts
I think you're both talking about the same thing.
In VNAV mode your magenta CDI (coupled to the FMS) would be up on your PFD so that's why you would need a raw data needle in the background. Is this what you were trying to say KyleRB?
The VNAV mode as far as I know (and educate me if I'm wrong) is an option on the XL. And the aeroplanes I've flown this was disabled so VS mode it was all the time.
In VNAV mode your magenta CDI (coupled to the FMS) would be up on your PFD so that's why you would need a raw data needle in the background. Is this what you were trying to say KyleRB?
The VNAV mode as far as I know (and educate me if I'm wrong) is an option on the XL. And the aeroplanes I've flown this was disabled so VS mode it was all the time.
Guest
Join Date: Apr 2003
Posts: 876
Likes: 0
Received 0 Likes
on
0 Posts
Yes I am little bit confused I must say.Just to clarify what is done on NJE's XLs.
Select FMS so it is displayed on the PFD (purple/magenta).
Then select LNAV so the aircraft tracks the course for the NDB/VOR.
Also have the NAV/ADF displayed on the PFD (to monitor the actual tracking of the Navaid being used).
V/S for decent.
That's it.
Thread Starter
Join Date: Oct 2008
Location: UK
Age: 44
Posts: 139
Likes: 0
Received 0 Likes
on
0 Posts
2604,
Yes I think that is what I am getting at!
Btw it's on XLS. VNAV mode is available and descent profile guidance appears on the PFD. The difference here is the jet will descend automatically if the FMS is programmed correctly with VNAV selected.
AMEX,
Just seen your post. I am talking about using VNAV instead of VS mode where the pilot is 'only' adjusting the power for speed control.
Thanks.
Yes I think that is what I am getting at!
Btw it's on XLS. VNAV mode is available and descent profile guidance appears on the PFD. The difference here is the jet will descend automatically if the FMS is programmed correctly with VNAV selected.AMEX,
Just seen your post. I am talking about using VNAV instead of VS mode where the pilot is 'only' adjusting the power for speed control.
Thanks.
Guest
Join Date: Apr 2003
Posts: 876
Likes: 0
Received 0 Likes
on
0 Posts
Now I get it 
To this, I would say it depends what your ops manual says. Check the part B (might even be in part A) as it should tell you for sure what you can do and can't do during a NPA.
If it is there then it is all good. If it is not, you could ask again to the Training Captain to show you the reference (you might have missed it) and since SOPs change quite often. it might be something newly amended, not there at all or about to be implemented.
That is if you are under an AOC of course.
I have been told by our training captain that we can use VNAV/FMS mode
If it is there then it is all good. If it is not, you could ask again to the Training Captain to show you the reference (you might have missed it) and since SOPs change quite often. it might be something newly amended, not there at all or about to be implemented.
That is if you are under an AOC of course.
Join Date: May 2006
Location: On the right of the clowns and to the left of the jokers
Posts: 307
Likes: 0
Received 0 Likes
on
0 Posts
Non Precision Approach Guidance
** Given you're using the UNS, I suspect that you have a Honeywell Primus installation, I don't recall how to set that up exactly. **
We have the Collins Proline 21 like the latest installations in the 560XL and it is possible to use VNAV in one of two ways. In both cases if the approach is based on a ground based aid, you can still legitimately fly using FMS guidance as long as the primary aid for the approach is identified and displayed independently (e.g. as an RMI needle on the HSI) I'll assume you're doing that when describing the LNAV mode in both cases.
The two VNAV options are:
1. Using Approach mode LNAV guidance ("APPR FMS1"/"APPR FMS2"):
The altitude preselect remains at the final assigned altitude (e.g. when vectoring for the approach. VNAV must be armed before the approach and the descent mode will be "GP" (Glide Path) The aircraft will descend to the ground if allowed to.
This makes for a precision approach and is generally used for GPS approaches where the option of a Decision Altitude(Height) is offered when using LNAV/VNAV guidance, In those cases there will be an alternative of an MDA(H) when VNAV guidance is not available.
2. Using NAV mode LNAV guidance ("FMS1"/"FMS2")
The altitude preselect is wound down to the MDA, it is possible to select the precise BARO MIN MDA as shown on the chart (10' resolution) in the Altitude Preselect. This is achieved by posting the MDA on REFS page 2/2 or 2/3 (on the PFD) and winding down the Alerter until that value is displayed.
Again VNAV is armed before the approach however in this case the descent mode is "PATH" which will be accompanied by the aimed mode "VALTS" and the aircraft will level off at the selected MDA.
I hope this helps.
We have the Collins Proline 21 like the latest installations in the 560XL and it is possible to use VNAV in one of two ways. In both cases if the approach is based on a ground based aid, you can still legitimately fly using FMS guidance as long as the primary aid for the approach is identified and displayed independently (e.g. as an RMI needle on the HSI) I'll assume you're doing that when describing the LNAV mode in both cases.
The two VNAV options are:
1. Using Approach mode LNAV guidance ("APPR FMS1"/"APPR FMS2"):
The altitude preselect remains at the final assigned altitude (e.g. when vectoring for the approach. VNAV must be armed before the approach and the descent mode will be "GP" (Glide Path) The aircraft will descend to the ground if allowed to.
This makes for a precision approach and is generally used for GPS approaches where the option of a Decision Altitude(Height) is offered when using LNAV/VNAV guidance, In those cases there will be an alternative of an MDA(H) when VNAV guidance is not available.
2. Using NAV mode LNAV guidance ("FMS1"/"FMS2")
The altitude preselect is wound down to the MDA, it is possible to select the precise BARO MIN MDA as shown on the chart (10' resolution) in the Altitude Preselect. This is achieved by posting the MDA on REFS page 2/2 or 2/3 (on the PFD) and winding down the Alerter until that value is displayed.
Again VNAV is armed before the approach however in this case the descent mode is "PATH" which will be accompanied by the aimed mode "VALTS" and the aircraft will level off at the selected MDA.
I hope this helps.
Join Date: Nov 2002
Location: UK
Posts: 138
Likes: 0
Received 0 Likes
on
0 Posts
KyleRB
You're right, I've seen this profile guidance on the PFD but I never could engage the VNAV mode and I've never seen it being done either. We were following the glidepath needle/cursor (forgot the name now. Brain failure) in VS.
Amex there's a mission for you next time you're on tour.
You're right, I've seen this profile guidance on the PFD but I never could engage the VNAV mode and I've never seen it being done either. We were following the glidepath needle/cursor (forgot the name now. Brain failure) in VS.
Amex there's a mission for you next time you're on tour.
Join Date: Nov 2002
Location: hearth EU
Posts: 108
Likes: 0
Received 0 Likes
on
0 Posts
By the way, you have a pilot FMS/Primus1000 manual that must be carried on board where all this is explained...
Worth to read it!
But do not use LNAV/VNAV if flying during cold weather, altitude correction compensation is not available...
Worth to read it!
But do not use LNAV/VNAV if flying during cold weather, altitude correction compensation is not available...
ECON cruise, LR cruise...
Join Date: Apr 2002
Location: MIRSI hold - give or take...
Age: 52
Posts: 568
Likes: 0
Received 0 Likes
on
0 Posts
...unless of course you are allowed to use manual temp corrections, in which case VNAV will work just fine Back to Part A and B, methinks 
Back to Part A and B, methinks
RNAV Approaches
Guys,
Take care out there.
I believe the Primus 1000 and UNS 1 systems could only be certified for BRNAV.
With BRNAV certification you are only permitted to use it down to MSA in terminal airspace. If you have full PRNAV you can go to the final approach fix and to go beyoind the final approach fix you need full GNSS approval.
Your AFMs will state your level of approval.
Overlay and back up is a good idea but take care to ensure the raw data is also still there.
MM
Take care out there.
I believe the Primus 1000 and UNS 1 systems could only be certified for BRNAV.
With BRNAV certification you are only permitted to use it down to MSA in terminal airspace. If you have full PRNAV you can go to the final approach fix and to go beyoind the final approach fix you need full GNSS approval.
Your AFMs will state your level of approval.
Overlay and back up is a good idea but take care to ensure the raw data is also still there.
MM
