More damage to Aussie GA – ILS training
There appear to be very few GNSS LPV approaches in Australia
There some GNSS APV (BARO VNAV) approaches in Australia, and more are being progressively rolled out. Refer to Dept website for schedule.
Dick, your CJ3 had BARO/VNAV capability for over 10 years, but for a majority of that time there were no baro approaches. What you were doing (or rather, should have been doing) was using your nav system as vertical advisory (meaning that all minimum descent steps need to be complied with). If you were actually flying them as vertical guidance (meaning minima descent steps can be ignored like an ILS vs LOC), then you have been flying them illegally. Until that VNAV line of minima appears on the chart then you are not permitted to fly them as guidance.
The main difference between GBAS/SBAS and BARO is the way the minima is determined. GBAS is considered CAT 1 precision. SBAS is certianly close but I am not sure if it is equivalent. Baro, still sits in the non precision space, as a non precision approach with vertical guidance.
Note, the provision of vertical guidance does not mean you have a precision approach.
Space Based Augmentation Systems (SBAS) provide augmented GNSS over a wide area. However, the net benefits of an SBAS to the aviation sector alone do not appear to be sufficient to justify the cost.
Thread Starter
Clear as mud. In the CJ I would keep the autopilot coupled and monitor the altitudes shown on the plate. Never anything other than perfect.
Lots of pilots doing that today. Are you suggesting a pilot must monitor with Baro Vnav. But not with LPV.? I hope not!
Many professional pilots believe they have been carrying out Baro Vnav approaches at places like Wollongong.
Surely the approach must be as or more accurate as an approach without baro and temperature adjustment and manually flown.
Lots of pilots doing that today. Are you suggesting a pilot must monitor with Baro Vnav. But not with LPV.? I hope not!
Many professional pilots believe they have been carrying out Baro Vnav approaches at places like Wollongong.
Surely the approach must be as or more accurate as an approach without baro and temperature adjustment and manually flown.
Clear as mud. In the CJ I would keep the autopilot coupled and monitor the altitudes shown on the plate. Never anything other than perfect.
LPV and BARO VNAV (APV) are not the same thing. No I am not suggesting monitoring of baro on an LPV approach. I am pointing out that there are no LPV approaches in Australia and currently no capability to fly an LPV approach. What you have been flying is APV using baro to provide the vertical guidance/advisory.
Many professional pilots believe they have been carrying out Baro Vnav approaches at places like Wollongong.
Surely the approach must be as or more accurate as an approach without baro and temperature adjustment and manually flown.
Thread Starter
Alpha. I can assure you that most professional busjet pilots I have spoken to do not understand that there is a difference.
I have spoken to many about this very point.
In my C208 I have the latest Garmin 750 and it has vertical guidance on the GPS approaches without any connection to the aircraft barometer. The approach can be coupled to the autopilot and it flys the aircraft on the 3’ approach path as well as I can. It is clearly not Baro Vnav. The CJs have baro coupling as well and you say they are not baro Vnav. What are they called then ?
I have spoken to many about this very point.
In my C208 I have the latest Garmin 750 and it has vertical guidance on the GPS approaches without any connection to the aircraft barometer. The approach can be coupled to the autopilot and it flys the aircraft on the 3’ approach path as well as I can. It is clearly not Baro Vnav. The CJs have baro coupling as well and you say they are not baro Vnav. What are they called then ?
Thread Starter
Thanks. I have read it. It states that baro Vnav is a 3 d approach.
So what is the naming difference between the approach’s performed by Cj3 with Baro assist compared to ones performed in my C208 without baro assist? Or are they treated identically by casa?
In both cases I am referring to approach’s performed at a non baro Vnav approved airport.
So what is the naming difference between the approach’s performed by Cj3 with Baro assist compared to ones performed in my C208 without baro assist? Or are they treated identically by casa?
In both cases I am referring to approach’s performed at a non baro Vnav approved airport.
We can autoland from a GLS with GBAS. Although it is only cat 1 it is expected to be cat 3b in the future. We can not autoland from a FLS (Baro compensated RNAV VOR etc). Although the data delivered from the FMS displays an RNAV in a ILS type format, it is by design still only a 2D approach.
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Have a look at AIC H05/18 and H28/16.
If you are flying a BARO AIDED GPS approach you are flying an RNAV APV approach to LNAV/VNAV minima. The approach is designed, and consequently the acft 'system' is coded with a vertical glidepath that clears obstacles by the required amount from the the Threshold at the Threshold Crossing Height (TCH) back up to the FAF. It is not designed with intermediate not below heights from the FAF vs distance to run as per a normal NPA. As there are no intermediate not below heights, the pilot cannot be responsible for ensuring not below heights are met, the DA is limiting.
If you are flying an approach in acft not certified with BARO VNAV, you are flying an RNAV NPA approach. You can only fly this approach to LNAV minima, or the old (being superceded) S-I GNSS minima label. This is an MDA. The approach is designed with intermediate not below altitudes vs distance to run. There is no vertical glidepath design and therefore no coding of a vertical glidepath to the threshold in the acft systems. As there is no vertical glidepath in the design of the approach - the pilot is responsible for ensuring the intermediate altitudes and finally the MDA are met.
This is where advisory VNAV can be confusing - some aircraft systems provide a vertical representation of the vertical profile on an LNAV only approach, i.e on an RNAV NPA. This is purely an aircraft generated capability, the vertical glidepath is not designed into the approach, therefore the vertical glidepath presented in the aircraft cannot be relied upon for terrain clearance. The pilot remains responsible for ensuring 'not below until x.x miles' is met. Think of it as an automated presentation of the advisory DME/ALT scale.
If you are certified for Baro VNAV - but do not have an accurate QNH or are outside the temp limits of the APV design, then you can only fly the LNAV minima.
RNAV LPV approaches (LPV = Localiser performance with vertical guidance) are the ones that require augmentation - this is not available in Australia. The fundamental design difference that usually enables lower minima on these approaches is that the design tolerances are angular (vertically and horizontally) as per an ILS, vice a fixed distance as per RNAV NPA and RNAV APV.
If you are flying a BARO AIDED GPS approach you are flying an RNAV APV approach to LNAV/VNAV minima. The approach is designed, and consequently the acft 'system' is coded with a vertical glidepath that clears obstacles by the required amount from the the Threshold at the Threshold Crossing Height (TCH) back up to the FAF. It is not designed with intermediate not below heights from the FAF vs distance to run as per a normal NPA. As there are no intermediate not below heights, the pilot cannot be responsible for ensuring not below heights are met, the DA is limiting.
If you are flying an approach in acft not certified with BARO VNAV, you are flying an RNAV NPA approach. You can only fly this approach to LNAV minima, or the old (being superceded) S-I GNSS minima label. This is an MDA. The approach is designed with intermediate not below altitudes vs distance to run. There is no vertical glidepath design and therefore no coding of a vertical glidepath to the threshold in the acft systems. As there is no vertical glidepath in the design of the approach - the pilot is responsible for ensuring the intermediate altitudes and finally the MDA are met.
This is where advisory VNAV can be confusing - some aircraft systems provide a vertical representation of the vertical profile on an LNAV only approach, i.e on an RNAV NPA. This is purely an aircraft generated capability, the vertical glidepath is not designed into the approach, therefore the vertical glidepath presented in the aircraft cannot be relied upon for terrain clearance. The pilot remains responsible for ensuring 'not below until x.x miles' is met. Think of it as an automated presentation of the advisory DME/ALT scale.
If you are certified for Baro VNAV - but do not have an accurate QNH or are outside the temp limits of the APV design, then you can only fly the LNAV minima.
RNAV LPV approaches (LPV = Localiser performance with vertical guidance) are the ones that require augmentation - this is not available in Australia. The fundamental design difference that usually enables lower minima on these approaches is that the design tolerances are angular (vertically and horizontally) as per an ILS, vice a fixed distance as per RNAV NPA and RNAV APV.
Bla Bla Bla...My eyes rolled back in my head after about two lines of the last post.
For F*cks sake, why can't we just have vertical guidance and a 3D Rnav approach just like an ILS with no bull****? I don't give a toss how a procedure is designed, I just fly the bloody machine! Why is GPS (sorry GNSS, which is still incomplete as Glonass and Galileo have incomplete constellations) so bloody confusing? Either it does the job or it doesn't? Ground based aids are so easy to use and you just fly the bloody machine. Thanks Air No Services for turning half of them off.
For F*cks sake, why can't we just have vertical guidance and a 3D Rnav approach just like an ILS with no bull****? I don't give a toss how a procedure is designed, I just fly the bloody machine! Why is GPS (sorry GNSS, which is still incomplete as Glonass and Galileo have incomplete constellations) so bloody confusing? Either it does the job or it doesn't? Ground based aids are so easy to use and you just fly the bloody machine. Thanks Air No Services for turning half of them off.
Thread Starter
Zanthrus. I agree with you. So darn complicated.
CASA has clearly failed in communicating this complexity to many professional pilots who fly these approaches.
Also if my autopilot coupled to the Garmin 750 gps exactly follows the 3’ glideslope shown on the printed plate why would I want to do the same thing manually with increased chance of human error?
It looks as if the CASA experts have got tied up with theory and complexity rather than what works best in practice
CASA has clearly failed in communicating this complexity to many professional pilots who fly these approaches.
Also if my autopilot coupled to the Garmin 750 gps exactly follows the 3’ glideslope shown on the printed plate why would I want to do the same thing manually with increased chance of human error?
It looks as if the CASA experts have got tied up with theory and complexity rather than what works best in practice
Last edited by Dick Smith; 17th Mar 2018 at 09:13.
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Rubbish.
it's no different to ILS having CAT I, II and III with different design and equipment requirements. If you only fly to Cat I then it's pretty simple. If you fly to Cat II or III then its more complicated.
The information is out there if you care to take more than 3 minutes to understand it. Dick, there was nothing in my post about whether you have to fly the approach with AP coupled or not. You can couple to them all, it doesn't care. If you are flying to LNAV minima then monitor the intermediate step heights down to the MDA.
If you are flying to LNAV/VNAV minima then make sure you have an accurate QNH and are in the temp range, then just worry about the DA/H. Not that hard.
it's no different to ILS having CAT I, II and III with different design and equipment requirements. If you only fly to Cat I then it's pretty simple. If you fly to Cat II or III then its more complicated.
The information is out there if you care to take more than 3 minutes to understand it. Dick, there was nothing in my post about whether you have to fly the approach with AP coupled or not. You can couple to them all, it doesn't care. If you are flying to LNAV minima then monitor the intermediate step heights down to the MDA.
If you are flying to LNAV/VNAV minima then make sure you have an accurate QNH and are in the temp range, then just worry about the DA/H. Not that hard.
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I'm military so I can't answer that question. I don't believe its a separate approach endorsement (admitting that I don't know the new licencing system very well).
Let me ask you a question with a hypothetical - say your CJ-3 is certified and equipped with a CAT III ILS with autoland and your Caravan is only Cat I ILS. Do you think its reasonable that you might have to use different procedures, different automation, and have a deeper level of understanding to fly CAT III to AL than to fly a CAT I. It's the 'same' approach after all.
This is no different, but to a narrower scope of difference in my opinion.
Let me ask you a question with a hypothetical - say your CJ-3 is certified and equipped with a CAT III ILS with autoland and your Caravan is only Cat I ILS. Do you think its reasonable that you might have to use different procedures, different automation, and have a deeper level of understanding to fly CAT III to AL than to fly a CAT I. It's the 'same' approach after all.
This is no different, but to a narrower scope of difference in my opinion.
Or are they treated identically by casa?
In both cases I am referring to approach’s performed at a non baro Vnav approved airport.
In both cases I am referring to approach’s performed at a non baro Vnav approved airport.
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ftrplt has explained it quite clearly. Don't just read the Garmin users guide to figure out what your aircraft is capable of, it depends upon how the Garmin was configured when installed. Your AFM will tell you what the aircraft is equipped for. Look in the limitations section, or the supplements section, and it will tell you if it's suitable for Baro VNAV, or LPV. If there are none of these statements then you must fly to the LNAV MDA only, you may use the vertical guidance as ADVISORY only (coupled or non coupled) to the MDA. If there are statements about Baro-VNAV/LPV, there will be associated limitations, abnormal and normal procedures you must follow.
The reason for the training is to cover precisely what has been discussed here, to ensure the pilot is aware of what approaches/minima the aircraft can/can't be flown to, and how to fly them. It's not just a CASA requirement Dick, FAA and EASA require it too. On my last re-current in the US we had to cover avionics differences, and guess what? We covered Baro VNAV and LPV, practiced using the temp comp system, identified the different annunciations for each approach. And the fact that for each different type of vertical guidance (ILS, VPATH, VGP, and LPV), the vertical path had a different symbol!!! So the training is very important because it ensures the pilot knows what he/she is looking at.
The reason for the training is to cover precisely what has been discussed here, to ensure the pilot is aware of what approaches/minima the aircraft can/can't be flown to, and how to fly them. It's not just a CASA requirement Dick, FAA and EASA require it too. On my last re-current in the US we had to cover avionics differences, and guess what? We covered Baro VNAV and LPV, practiced using the temp comp system, identified the different annunciations for each approach. And the fact that for each different type of vertical guidance (ILS, VPATH, VGP, and LPV), the vertical path had a different symbol!!! So the training is very important because it ensures the pilot knows what he/she is looking at.
I’m confused. An GNSS LPV approach does not use barometric data. The height element for the G/S is satellite derived with WAAS augmentation. Flown like an ILS. My C182 with G430W. flies LPV to CAT I limits.
Is there no WAAS or SBAS covering Australia?
Is there no WAAS or SBAS covering Australia?
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CP,
There is no SBAS coverage in Australia for aviation.
There are no approaches designed/promulgated to LPV minima in Australia.
At least in the avionics I am familiar with (my caveat) you need to select/check the augmentation provider (WAAS in the US for eg) when you load an LPV. I would expect if the augmentation service is not available/being received, then you would/should get alerting that the LPV approach you are attempting is not valid. Regardless of the avionics, the approach chart in OZ wont have LPV minima, so you cant fly in LPV mode anyway.
In OZ you have RNAV NPA (LNAV minima) or RNAV APV (LNAV/VNAV minima). Both use the barometric altimeter for height awareness, APV has the (usually) 3 deg GP designed into the approach and coded in the system, the NPA does not. The NPA uses intermediate step heights instead of a GP.
You can search for 'LAX RNAV Approach' to look at an RNAV(GPS) chart (not the RNP chart - Flight Aware website is good) to see the 3 different minima boxes - LPV, LNAV/VNAV, LNAV.
There is no SBAS coverage in Australia for aviation.
There are no approaches designed/promulgated to LPV minima in Australia.
At least in the avionics I am familiar with (my caveat) you need to select/check the augmentation provider (WAAS in the US for eg) when you load an LPV. I would expect if the augmentation service is not available/being received, then you would/should get alerting that the LPV approach you are attempting is not valid. Regardless of the avionics, the approach chart in OZ wont have LPV minima, so you cant fly in LPV mode anyway.
In OZ you have RNAV NPA (LNAV minima) or RNAV APV (LNAV/VNAV minima). Both use the barometric altimeter for height awareness, APV has the (usually) 3 deg GP designed into the approach and coded in the system, the NPA does not. The NPA uses intermediate step heights instead of a GP.
You can search for 'LAX RNAV Approach' to look at an RNAV(GPS) chart (not the RNP chart - Flight Aware website is good) to see the 3 different minima boxes - LPV, LNAV/VNAV, LNAV.
Thread Starter
The honest post by Cessnapete shows the problem.
As stated before I have spoken to professional pilots who fly busjets in Australia and they are as confused as I am.
Some also believe we have WAAS here.
As far as I can remember all the aircraft I have flown that are ILS equipped allow for one type of ILS approach. So very simple.
As stated before I have spoken to professional pilots who fly busjets in Australia and they are as confused as I am.
Some also believe we have WAAS here.
As far as I can remember all the aircraft I have flown that are ILS equipped allow for one type of ILS approach. So very simple.