Looking for a guide or tutorial for RNAV, RNP and other approach types.
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With the Autopilot system having its V-NAV mode U/S (unserviceable), im looking for a guide or tutorial for conducting RNAV approaches. I am finding that without proper Vertical guidance on approach that the pilot workload is way too high in adverse weather conditions to keep looking at an approach plate/chart. (high gusting winds - causing speed fluctuations, vis down to minimums, etc).
any suggestions or work arounds would be aprecated.
Thanks in advance.
-Pete -
@Davidaa sorry but the statement that the 146 is not approved for RNP (RNAV) approaches seems to be incorrect.
The 146 and its crews here in Australia and elsewhere, regularly conducts these types off approaches down to minimums. Australia doesn't have ILS systems installed everywhere like in Europe or America, so the use of RNP non precession approaches is extremely common at most airports. That includes airports like YPAD (Adelaide international) or YSCB (Canberra international) where there is only a single approach with an ILS.
ide also note that in australia GNSS approaches used by smaller aircraft have their own approach plates that have different minimum requirements.
I refer you to two separate documents that could not exist of the 146 was not approved for these kinds of approaches.
1, This Australian Transport Safety Bureau (ATSB) report of a incident regarding a BAe 146 200 that was conducting an RNP approach:
https://www.atsb.gov.au/publications/investigation_reports/2024/report/ao-2023-004#aircraftdetails10
2, This Paper produced by the UK's CCA: CAA PAPER 2007/06 RNAV (GNSS) Non-Precision Approach –
Flight Trials Analysis Report. this paper lists the 146 as one of the aircraft sampled that used an RNAV approach.
https://www.caa.co.uk/publication/download/13505 -
RNAV and RNP are not the same! I think the 146 is capable of RNAV but not equipped for RNP. Please correct me if I am wrong.
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@Rhinozherous from the first link i included in my reply above:
" air traffic control cleared the flight to track to the waypoint SARUS. This waypoint was the initial approach fix for the required navigation performance (RNP) approach for runway 33 at Rockhampton and the tracking allowed the crew to proceed directly from the cruise and descent to a straight-in RNP approach"That is in fact one of the reasons why the 146 has a "VNAV" button on the autoflight panel. it is used primarily for providing vertical guidance on RNP approaches.
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So firstly I’d it a 146 or an RJ? Also the RNAV capability is largely defined by the FMS fitted to the aircraft and also depending on the certification standard the displays, eg glass cockpit. Certification standards may vary across the globe and dispensations may also apply. But as a general rule 146’s are not/were not capable of RNP approaches. There may be a few aircraft which have been upgraded to facilitate this.
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The appropriate procedure would be to divert to an alternate with suitable conditions. You're flying a '90s era (best case) bird without VNAV into highly adverse conditions on an approach you aren't remotely equipped for. Solo. I think that's usually the point where all the holes of the cheese line up and the sad music starts.
The procedure you can follow is to use the GPA table on the approach chart (or do your own calculations) and maintain GS and VS to achieve the GPA after the final descent fix. You would at least need a second set of eyes to monitor the approach under those conditions; i.e., have an eye on vertical and ground speed and check your heights at the documented distances to make corrections on the fly.
And to let out my facetious self: yes, the simulated 146 can fly RNP approaches. All that means is that your plane is sure enough of its lateral position in space at any given time, and so far I'm confident it always is as long as you're navigaing with the FMS. What the plane cannot do is fly an automated final approach, which isn't part of that. What you probably cannot do is maintain a glide path to the necessary standards.
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Bin Chicken.
The JF146 models don’t include a VNAV button as to do a RNP requires the correct type of FMS and database of airfield approaches. The early model UNS is not a normal FMS for the 146. Quite possibly the GNS XLS Enhanced may be required to do RNP.
Fitted ann upgraded FMS as part of an approved mod. Would also prompt the inclusion of a VNAV button.