LOWI RNP Z Rwys 08 and 26
Hi,
I posted on Navigraph the following:
Hi,
All the way supposely to go on the descent angle from WI750, the aircraft does not descend and all the waypoints stay at 13000 (see picture).
Win 7 - P3dv4.5 - MJC Q400 - Airac 2012.
I would like to know if the problem is coming from Navigraph data or is it because this type of procedure is not implemented in the Majestic Q400?
Id does not make a big difference with the other available procedures, only to have much lower minimas which could be handy sometimes.
Thanks and regards,
JP
Comments
Hello, we had the topic here before, unfortunately also without a satisfactory answer. Unfortunately, I haven't had the time to find a similar approach, but I think it's because there are waypoints within the approach that have no height restriction. This means that in the approach at least the last known restriction, here 13,000 ft, is retained and transferred to the following waypoints. The aircraft cannot sink at all using VNAV, since it is flying absolutely correctly on the specified path of 13000 ft. Since I mean that no changes may be made on the F / PLN page within the approach waypoints, it only remains to adhere to the descent specifications for the 3.60 ° angle according to the charts. From WI750 on I am allowed to descend continuously to 2900 ft. It is the same from the other side, here the 9500 ft are retained.
http://www.ivao.at/wiki/LOWI_Anflüge
The last point relates to this approach and also basically states that from WI750 to about WI754 one sinks to the 2900 ft. You are then still 2.6 NM from the Rwy and have a good 1000 ft to dismantle
Hi FraPre,
Thank you so much for your answer and the link.
Landing Rwy 26 is quite OK with the LOC R Rwy 26 2250 Ft MDA even with the LOC DME EAST and the RNP E Rwy 26 with 3300 Ft MDA.
For Rwy 08 it is a bit more complicated as the RNP Y gives us MDA 7100 Ft and the LOC DME WEST 5000 Ft followed by the tricky special circling procedure.
If we could fly the RNP Z Rwy 08 it would be nice but I do not think we would be allowed (RL) to start our descent from WI750 to WI754 only on following the 3.60° path without any intermediate reference so I have to forget about this procedure until our Q400 would be fully equipped to do it.
I suppose you know this video:
I was quite surprised to see that he was doing all the circling approach with the A/P ON. So I found out that it would be possible if you stay close to the mountain following the power line. The speed is the key factor. Flaps 15° Vref+5, starting the final turn at D3.5 OEV VS -1000 Ft/mn and Flaps 35 with the new Vref+5 before the end of the turn. It does not work first time but, as you know, we cannot go to LOWI without a special authorization so we have to train.
Anyway what a lovely place to fly.
Regards,
JP
Why do you want (what is RL ???) not to fly the approach starting from WI750 down to the MDA of 2900 ft?
You regulate the VS using the ground speed according to the table on the charts.
By the way, in the video you can see that the descent is also controlled by VS, even if it is the Special LOC DME East.
You should check whether the Majestic Dash is certified for the RNP Z Rwy 08 (AR) at all.
Of course you can also use the autopilot for a circling in the approach, whereby the bank angle in the turn is then limited to 24 °.
The reference points and for the circling are clearly visible in the charts, and of course you stay close to the mountainside
RL: Real Life or we can also say RW: Real World.
On the RNP Y you have a vertical reference for each WP and also with the distance to the threshold so when going down in V/S you know for each reference point if you are OK, too high or too low.
On the RNP Z from 13 000 Ft WI750 up to the decision altitude 2 900 Ft which is less than 1 000 Ft from the ground and with few turns you do not have any reference between the two so I do not see how to fly safely this approach with the equipment that we have at present in our Q400.
For the Special LOC DME East each individual operator is giving minima by Austro Control so, if we want we can decide that our MDA is whatever we like (of course only with the sim). On the approaches to Rwy 26 with the LOC there is also a GS indication which is not a full ILS and you are allowed only to use V/S and LOC but not APPR.
JP
http://majesticsoftware.com/forums/discussion/511/rnav-incorrect-logic-or-airac-1908-broken#latest
in short, no solution was found and we cannot perform precise landing procedures(RNAV RNP) in manual mode...
Hi Niksan29,
You are absolutely right and I forgot this discussion, stupid me.
I understand this procedure is not possible with our FMS
Maybe we'll get a full RNP one day. It is only on few airports, like LOWI, that we need to use this procedure in case of low ceiling especially on Rwy 08.
Well, if the ceiling is below 3100' and Easterly winds we just don't go there and wait for the weather to improve like it was before the FMS.
Regards,
JP
yes it really was so long ago
and yes, at the moment we cannot correctly execute almost all schemes with a minimum at LNAV\VNAV
as comrade
> @kroswynd said:
The FMS is not perfect and still as some flaws. We'll have to have a closer look into this once we are able to complete our primary focus at the present time. Having re-written its code to make it compatible with the 64bit platform could pose additional issues but it is certain worth taking a look at when it's time to address bugs/flaws.
so we can only wait
Fortunately, there are other approaches too.
In addition, it is up to you how realistically you want to fly in the simulator. I assume that almost everyone has already flown the approach in EGLC, although the Majestics Dash does not have a steep approach approval either.
Hi FraPre and niksan 29,
Again, like LOWI, an approach to EGLC is not very common and we should remember that the Majestic Q400 has been programmed with a certain Q400 using a particular UNS.
Of course we can decide within the Sim to have our own approaches and I do that for testing like the night approach to CDG in daytime as I mentioned in another post.
Sometimes I even do crazy things which are not in the books often finishing in a crash.
However, when I do a full flight with FPL, I follow all the rules like I was taught when I was doing real flying and I would GA at the minima if I do not see the lights.
The fantastic thing with the Sim is that everybody can do what he likes without loosing his licence!!!
Regards,
JP
What you don't have you can't lose
When folks express disappointment with the Q400's functionality, I hope that most are aware that some of the items requested are specific "options" that the operator(s) have installed based upon needs for the type of operations they perform, and of course implement some that allow for safer operation of the aircraft. I too would like to see many of some of the said "options" implemented, but in so doing this would also more than likely create further disappointment as it would very possibly affect the pricing structure of the product line.
The MJC Q400 was originally designed from access that was granted by an operator that did not have many of the options that users request. We have since implemented a few over the years, and while this one may be a simple one we would need supporting data so that we can ensure that it is programmed as close as possible to the real system.
Some of the other issues regarding RNAV fall under the same premise and I am sure that there are a few pilots who would be willing to share this information with us for systems detail and implementation. We will however say that there will be some features that will not be done primarily to the time required. Please also bear in mind that although in the STAR procedures our FMS is missing the intermediate calculation of the altitudes, it will not do so in the approaches as it is simply not safe. If Navigraph does not specify the correct altitudes, there is no way we can produce a 3D approach. However, we can of course communicate to the Navigraph team any inconsistencies, such as that to LOWI approaches in order to get them working as they should (which is on our list for future updates).
As a company, we have to make decisions that are best suited for us from a development perspective, and that allows us to get a product that balances the best of both worlds. If we see it feasible to implement something further from the "entertainment" aspect we will. We also will do our best to further improve the product as we have been continuously doing. One chapter at a time is the best we can do, and putting the TRAINING/COCKPIT Editions out is where we are really focused at the moment.
2020 has put many of the projects lined up for this year's tentative release a few steps back, as our families take priority, but we are pushing forward.
Apologies for getting a bit long winded on this but I thought it necessary to add some overall insight o this matter, and as always we appreciate the discussions on these topics to assist us in trying to make better product.
Cheers
Hi Simeon,
As far as I am concerned I am not disppointed at all by the Q400 that you have made and I am a Majestic faithfull customer since day one and not flying anything else as a liner.
I never flew the real Q400 but having quite a comprehensive documentation, I can say that everything looks like the real thing.
In my last post I said:
And it is understandable that you cannot replicate all the options on the FMS. Already what we have is a great step from what I had when I was doing some real flying,
I mentionned few things that I would like to see on the FMS on your topic regarding suggestions and I said that I would not mind paying a bit extra as it would be quite normal that if you do something extra which is going to take time we'll have to pay for it.
When I sent my first post on the LOWI RNP Z topic I did not know where the problem was coming from and I posted the same on the Navigraph forum but never got any answer.
Carry on the good work.
Kindest regards,
JP
@kroswynd
Thank you, we know that it is definitely not easy to satisfy everyone, especially with special equipment, such as that for a steep approach or a certain RNP ability in relation to P-RNAV. With the sample that was virtually available to you, you still developed a really great aircraft for us that sets standards. I like to fly as authentically as possible, but I also fly at least the steep approach in LCY from time to time, but I find many great destinations in the network of LOT, LG, AUA, OS, BT, WS and formerly BE, EWG and AB can approach normally. If there are further improvements in the future, I'll gladly accept them, but I can also have a lot of fun. Thanks!
> Please also bear in mind that although in the STAR procedures our FMS is missing the intermediate calculation of the altitudes, it will not do so in the approaches as it is simply not safe. If Navigraph does not specify the correct altitudes, there is no way we can produce a 3D approach. However, we can of course communicate to the Navigraph team any inconsistencies, such as that to LOWI approaches in order to get them working as they should (which is on our list for future updates).
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just wanted to clarify, you have official information: is there an intermediate altitude calculation in a real dash 8 for RNAV app?
and of course we know most other plans with mcdu/fmc can do this and these are standard procedures.
> @jpgmultimodal said:
> When I sent my first post on the LOWI RNP Z topic I did not know where the problem was coming from and I posted the same on the Navigraph forum but never got any answer.
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As we understand it, this is not a Navigraph problem, there really is no published altitude for intermediate points, they simply cannot publish it because this information is not in real charts, this is the task of calculating the built-in mcdu/fmc.
I once promised to look for a similar RNAV RNP approach with intermediate points. Here at the RNAV RNP Y Rwy 05 in NZQN there are even several between FAF and Rwy, but all of them have intermediate heights in both the charts and in the FMC. I haven't flown it yet, but shouldn't theoretically lead to problems like in LOWI
http://www.aip.net.nz/pdf/NZQN_45.1_45.2.pdf
Hi,
NZQN very interesting and a bit similar to LOWI.
Few points to note: See on the enclosed Jeppesen that the altitude is given for QN555 (2413') but not after as the minima is 2300' and they state that it is subject to special approval so we cannot get the information. We see that C and D aircrafts are not authorized. However the New Zealand AIP is completlely different.
The FMS gives the intermediate altitudes for this procedure in NZQN but not for a similar procedure in LOWI.
I am just thinking of maybe another way of doing these approaches:
When you are starting your final descent OMUBO (for NZQN) angle 3°20 or WI750 (for LOWI) angle 3°60 is there a special option in some FMS to get these values and descend like an ILS? Of course we could do that by maths as we know the altitude, the angle and the distance but that would not be the "legal" way of doing it.
A bit away from our topic; I think on the Airbuses you can select a flight path angle and then it is easier to do these approaches as you do not care about the GS for your calculations for the VS.
Does someone knows how it could be achieved with the Q400 and the UNS FMS?
Regards,
JP
> I am just thinking of maybe another way of doing these approaches:
> When you are starting your final descent OMUBO (for NZQN) angle 3°20 or WI750 (for LOWI) angle 3°60 is there a special option in some FMS to get these values and descend like an ILS? Of course we could do that by maths as we know the altitude, the angle and the distance but that would not be the "legal" way of doing it.
>
> A bit away from our topic; I think on the Airbuses you can select a flight path angle and then it is easier to do these approaches as you do not care about the GS for your calculations for the VS.
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Hello!
Unfortunately, there is no other way, we cannot do it(RNAV app)manually, especially when there are requirements for increased accuracy(RNP).
The VNAV path is computed using aircraft performance, approach constraints, weather data, and aircraft weight. The approach path is computed from the top of descent point to the end of descent waypoint, which is typically the runway or missed approach point(the same on the Boeing and Airbus).
Hi,
You are right but as it is only on few airports that we would need RNP AR APCH so it is quite allright.
We have to use what we have and set the minima accordingly.
Most of the Q400 operators have most probably the same specifications for their FMS than ours and it is fine for what we are doing.
Still a good bit of flying to do with this fine bird.
Regards,
JP
> You are right but as it is only on few airports that we would need RNP AR APCH so it is quite allright.
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not only, also we cannot perform many RNAV app with VNAV minimum
> Most of the Q400 operators have most probably the same specifications for their FMS than ours and it is fine for what we are doing.
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I'm not one hundred percent sure, but I still think that a real Dash can do it
P.S
I would very much like to see a video(if it exists) where it is executed in real life with PFD view
Each airline may have ordered their Dash with different equipment, or they are differently certified. We can only guess what our Dash can or should be better. In a MALEV manual I had seen that the Dash was initially only capable of B-RNAV. In the meantime at least our Majestics is P-RNAV capable and I fly RNAV GNSS approaches with an RNP of 0.30. I won't fly an RNAV (RNP) like in your case LOWI with it.
I don't know if I had linked this before, but here is a little system check of the Dash for RNAV and RNAV AR.
http://gf3.myriapyle.net/aero/Fichiers/RNP.pdf
> I fly RNAV GNSS approaches with an RNP of 0.30. I won't fly an RNAV (RNP) like in your case LOWI with it.
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but Innsbruck also requires 0.30...
and tell me what differences do you see?(between RNAV GNSS approaches with an RNP and RNAV (RNP) )
> I don't know if I had linked this before, but here is a little system check of the Dash for RNAV and RNAV AR.
> http://gf3.myriapyle.net/aero/Fichiers/RNP.pdf
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yes, I remember this document, by the way, the author did not mark the problem in Innsbruck that we are discussing
@niksan29
Apparently the Flybe FMS is the same than ours and we can see that they use procedure RNP Y Rwy 08 with the same minima 7100':
They are qualified to do the Special LOC DME East which does not need special equipment but a special authorization. We can fly this one and we can "qualify" ourselves for the minima that we have decided:
@FraPre
I have seen this document few years ago. Very well done. A good point mentioned is that we should not edit an approach segment.
I think, but not certain, that the Aerosoft Navdata Pro is used for the LOWI RNP. Anyway he points that there are differences with the Navigraph database.
Just a thought: could be that Navdata Pro has calculated the path for the RNP Z Rwy 26?
Since this document has been written there has been some improvements in our Q400 and now the curves are showing.
Something important to note: when you have a sharp turn or in a holding with the FMS, it starts, most of the time, the turn the other way round and comes back afterwards. we have discussed this in another post and we can do nothing about it as it was explained by Kroswynd that this problem is within the sim (FSX or P3D). A way to avoid it is to start the turn in HDG mode.
The problem generally occurs when, in a VNAV-guided descent, a navigation point with a defined altitude restriction is followed by one or more waypoints that have no restriction. The last altitude restriction is then transferred internally to these waypoints, but without generating an entry on the F / PLN Page. The problem can only be seen on the PFD. That's how I tested it in EDDF at STAR ASPAT. The system only reacts again when, after flying over a waypoint without altitude restriction, a point with a new altitude restriction follows. As a rule, however, the route no longer fits here in order to cope with the upcoming reduction in height in the available route. VNAV is disconnected because the required path cannot be reached.
Sorry, I forgot to send the last comment. I just saw that it was still unsent in the writing box. I don't even check whether something overlaps in our comments.
You're right, over the years the Dash has been and will be improved if the airlines want it. The first Dash from MALEV (Hungarian Airlines) only had a B-RNAV, so it couldn't fly any RNAV approaches! This topic is really not mentioned in the MALEV manual, while for all other variants (ILS, LOC, VOR, NDB) it is described and specified how they are to be flown, including the AP modes.
Dash 8 is now available with P-RNAV, even RNP AR compatible, although the airline itself and the ventilation must be certified. Our Majestics Dash has, if we take it strictly, a P-RNAV, so normal RNAV and RNAV (GNSS / GPS) can fly.
RNAV RNP should not be used, as RAIM is prescribed for RNP, but this is only indicated here and only comes in the training version.
The simulated FMS has software version 802.0, but actually there is already .8, I mean.
We will probably not come to a satisfactory answer here. If we take the Majestics Dash as it is up to date, RNP approaches are not possible. But we're in a simulator, if she does, and yes, she can vml. show curves with Navigraph, it just flies. RAIM is not available, but there is no real GPS satellite simulation or errors in the GPS signals.
> The problem generally occurs when, in a VNAV-guided descent, a navigation point with a defined altitude restriction is followed by one or more waypoints that have no restriction.
at the moment I am most worried about this problem, and also the fact that is not auto add +50 feet to the runway thresholds(this is the lesser of the problem but still) in to FPLN
It seems to me that these two problems do not exist in real life, and let's hope that someday when will be fixed for us too
Navigation database should be obtained from a qualified supplier that complies with RTCA DO-200A / EUROCAE ED-76A standard
The operator must check the navigation data with the information in the charts before they can be used for navigation.
Depending on the airline, I imagine it will be quite time-consuming to check every RNAV procedure, and every month if the data changes, but apparently it is so and runs in the background. If the pilots call up the data in the cockpit and load an RNAV approach, everything should be validated, and only approaches that the aircraft is allowed to fly should be offered! You still have to check it again. Whether the responsible employee of the airline can and should correct incorrect data (e.g. the Rwy crossing height) is no idea. I would also assume that the data supplier creates a basic set that is then converted into the various FMS data formats. If the errors do not arise, the basic data should actually be the same for all aircraft, with the same supplier. Attached is the data for an RNAV approach from my hangar, where you can see that almost nothing is the same. All approaches were clearly coded and accessible.
Majestics Dash
Distance FAF ROGAB - Rwy 26R 8.9 NM, no GP (GP is only visible with active Approach Mode (LNAV APPR) ), EoA Alt (Rwy) 122 ft
Aerosoft A320
Distance FAF ROGAB - Rwy 26R 9 NM, no GP, EoA Alt (Rwy) 117 ft
PMDG 737NG
Distance FAF ROGAB - Rwy 26R 8.9 NM, 3.03° GP, EoA Alt (Rwy) 172 ft
Digital Aviation CRJ
Distance FAF ROGAB - Rwy 26R 8.9 NM, no GP, EoA Alt (Rwy) 168 ft
Qualitywings 787
Distance FAF ROGAB - Rwy 26R 9 NM, no GP, EoA Alt (Rwy) 168 ft
iFly 747
Distance FAF ROGAB - Rwy 26R 8.9 NM, no GP, EoA Alt (Rwy) 120 ft
Captainsim 757
Distance FAF ROGAB - Rwy 26R 9 NM, no GP, EoA Alt (Rwy) 170 ft
According to the corresponding approach chart, the Rwy crossing height is 51 ft, the Rwy height is 117 ft. Thus, only the 787 and the CRJ provide the correct height at the end of the Approach (EoA)
So whether it is a "problem" with Majestics is doubtful.
@FraPre
Very interesting approach to the different aircrafts using RNAV.
As you mentioned, our Majestic Q400 has not the GP unless we activate the baro-VNAV so the results would not be as precise as a full VNAV RNP.
With the sim we have to take into account that (for FSX and P3dv4.5) it is only the Apt Elev that is taken into account, not the Rwy Elev.
Another point that we have to consider is that in Europe we use Hpa for the QNH and it is not as precise as the In of Hg. We have 28 Ft between two Hpa values so we can have a barometric error up to 14 ft. Also the pressure can change sometimes rather rapidly and until the new QNH is given we can have a bit of error to add as well.
It took me sometimes to find out that your exemple was EDDT and I flew the approach with an average of 20 to 30 Ft below the altitude given on the chart with the A/P and LNAV VNAV.
In real life, during an approach, the PNF would give to the PF the distance and altitude and mention above or below.
Anyway, as we cannot fly our approach below 468 Ft in IMC, so we would be visual and it does not matter if the FMS does not give us exactly the 50 Ft above the threshold.
I would completely agree with you that there is no problem with Majestic when doing these types of approach.
JP
Sorry, I probably forgot to mention that my values refer to the good old Airport TXL.
It is that I understood as I used to fly there but now it is not used much more.
Tempelhof was something as well. Gone but not forgotten.
Yes, when it comes to closing airports with historical significance and history, Berlin is world class!
I don't know why we have different data, but my Aerosoft and PMDG add 50 feet(in fplan mcdu/fmc) to crossing the threshold
P.S
ILS and non-precision approach. ICAO Pans-Ops states:
5.3.2 Determination of the descent gradient for a non-precision approach with FAF
The descent gradient (g) for a non-precision approach with FAF is computed using the equation: g = h/d. The values for h and d are defined as follows:
a) For a straight-in approach use:
d = the horizontal distance from the FAF to the threshold (Cat H, LDAH); and
h = the vertical distance between the altitude/height over the FAF and the elevation 15 m (50 ft) over the threshold.
@niksan29
Absolutely right regarding the theory for the 50 Ft at the threshold. This is a rule that should be followed even in visual approaches and the Toff and Ldg calculations are done with this parameter in mind.
However it appears that with the sim it depends of the way the approach was designed and also the parameters that I mentioned in my above post.
@niksan29 and @FraPre
When I flew the EDDT RNAV Rwy 26R, the results were acceptable and now I decided to fly another approach:
EDDB RNP Rwy 25L
This approach is designed with LPV CAT 1 which is the lowest minima that we can have when flying this type of approach with, of course, the right equipment.
As we are not equipped for this, it was flown Baro-VNAV. Here are the figures:
8 Nm 2800' +50'
7 Nm 2430' same as shown on the chart
6 Nm 2090' -30'
5 Nm 1800' same as the chart
I missed the 4 nm check
3 Nm 1150' -10' RA 1010'
2 Nm 820' -20' RA 680'
At the minima (when I had a look) I was at 440' instead of 445' and the RA 280'
So when checked with the RA against the QNH altitude value the results were between 140' and 160' for an airport Elev of 156'. Not bad.
I decided to keep the A/P all the way down and, as you can see, the height at the threshold was 45'.
I did not enter the Vref and MDA as it was just for a quick test
I let the A/P all the way down and it disconnected itself at 10' (RA) just before the PAPI lights.
I cannot be affirmative but it looks that when an approach is designed by the FMS data provider it looks more precise if this approach is designed to be flown LPV CAT than LNAV/VNAV.
Keeping in mind that we have a sim costing only few $/€ instead of multi millions real aircrafts or full flight simulators it is as near as the real thing.
We are a bit away from my original post but I have made some progress understanding as the FMS approaches are flyable with our Majestic Q400.
JP
I got some explanations from RW Q400 users: French Fire Fighters.
Their old Q400s have only LNAV and LNAV-VNAV Baro possibilities.
The new Q400s that they are getting now are LPV 200 Ft CAT I equipped.
Our Dash is not equipped (yet) with the latest LPV so we should do only LNAV-Vnav Baro.
https://www.croatiaairlines.com/Croatia-Airlines-will-use-EGNOS-for-LPV-approaches
I can live well with Baro-VNAV and thus land at 99% of airports in addition to the classic navigation methods in the approach. We will see whether SBAS / GBAS will even be implemented in the simulator, then the numerous add-ons have to be adapted.
Good evening, the 99% are more symbolic because I can't check what I'm really "allowed" to do with the Majestics. Every real aircraft is delivered with corresponding certifications (customer request), which show what the aircraft is capable of and is allowed to fly (RNP, RNP AR, Steep Approach, ...). The first Dash 8q400 only had B-RNAV equipment, our Dash here already has P-RNAV, but I am always missing a clear statement from the manufacturer about what the add-on aircraft can and should really do. But that only plays a real role in models that have been implemented as excellently as the Majestics Dash, the PMDG Boeings and the FS Labs A320. So the 99% stands for every RNP RNAV approach up to 0.30 RNP, with less I would not be sure and would leave it, i.e. everything that is RNAV RNP AR. The Majestics also has no equipment for the steep approach, so here too London City would fall below the one% (I have already flown the approach).
So there is almost always a legal way for me to land, and if not, that's how it is and I have to evade, that would also be real. An A320 captain friend of mine once wrote to me from the airport cafe that he is stuck, his plane is not coming, why? The main runway has an ILS, but was closed due to construction work. The parallel runway has no ILS, only an RNAV (GPS) and a VOR approach. The Airbus A320, an older model, did not have a GPS. ILS approach didn't work, RNAV (GPS) didn't work either and the clouds were too deep for the VOR approach.Good evening, the 99% are more symbolic because I can't check what I'm really "allowed" to do with the Majestics. Every real aircraft is delivered with corresponding certifications (customer request), which show what the aircraft is capable of and is allowed to fly (RNP, RNP AR, Steep Approach, ...). The first Dash 8q400 only had B-RNAV equipment, our Dash here already has P-RNAV, but I am always missing a clear statement from the manufacturer about what the add-on aircraft can and should really do. But that only plays a real role in models that have been implemented as excellently as the Majestics Dash, the PMDG Boeings and the FS Labs A320. So the 99% stands for every RNP RNAV approach up to 0.30 RNP, with less I would not be sure and would leave it, i.e. everything that is RNAV RNP AR. The Majestics also has no equipment for the steep approach, so here too London City would fall below the one% (I have already flown the approach).
So there is almost always a legal way for me to land, and if not, that's how it is and I have to evade, that would also be real. An A320 captain friend of mine once wrote to me from the airport cafe that he is stuck, his plane is not coming, why? The main runway has an ILS, but was closed due to construction work. The parallel runway has no ILS, only an RNAV (GPS) and a VOR approach. The Airbus A320, an older model, did not have a GPS. ILS approach didn't work, RNAV (GPS) didn't work either and the clouds were too deep for the VOR approach. Here, too, there are restrictions in day-to-day operation.
@FraPre you duplicate your post but it does not take the meaning away.
You are absolutely right and when I was flying we were landing about 99% (minimum) to the airports that we were going to even where the weather was (and is still) not always the best in winter: Ireland, Scotland, West France.
We did not have LNAV but only ILS, VOR, NDB and on some airports only gonio (the ATC was giving us QDM). On top of that as we were not a regular operator our minimas were higher than the large national airlines. I think, but I do not remember exactly, we had to multiply the minima by 1,6.
So with the equipment that we have with the Majestic Q400 if doing an ILS CAT II we could go down to 100 Ft, 200 Ft CAT I and LNAV-VNAV around 300 Ft (depending of the environment) which means that we can land most of the time.
LOWI is quite different than most airports due to its situation. I do not know the real place but I understand that sometimes there is quite a strong foehn effect and, usually, if there are strong winds, the cloud base is not too low and we could fly there.
Anyway, before to go you have the METAR and TAF and if you see that the forecast is going to be low clouds and bad visibility lower than your minima all day, you simply do not take off.
ILS are disappearing on small airports and are replaced by LPV due to maintenance cost but when you see the new Berlin, all four runways have ILS and are approved up to CAT III so the ILS have still some good years to live.
JP
I did not want to double my contribution, but only responded to the 1% of the previous post. I had the feeling that concrete examples were really wanted here, but that is not the case. The 1% only covers the fact that you are not 100% sure.
Regarding the equipment aboard the Q400 you could say that 100% of the airports are accessible. Of course according that all the criteria such as lenght of rwy, altitude, temp, mass, weather, etc. are met.
In principle, this statement will be correct, no matter which instrument approach procedure fits and can be flown in the end.
It also works if there is no instrument approach at all as it is on many airports in Africa. So yes: 100%.
in my opinion: a percentage of what not allowed, we cannot perform
includes all the same:
1)a VNAV-guided descent, a navigation point with a defined altitude restriction is followed by one or more waypoints that have no restriction.
2)Steep Approach(and i wonder what is the difference between an aircraft admitted to this and
our Dash 8)
3)RNP RNAV approach with a value less 0.30 RNP
P.S
although the last two options are probably impossible to implement physically in the framework of the simulator.
since for the Steep Approach there is no influence on the physics model from the arm steep approach mode.
and for the RNP we always have an ideal satellite signal and no interference;)
I can't find any more about whether it's really just this one point, I don't know.
But maybe we are drifting away in the discussion. The Majestics Dash offers a certain level of navigational and flying options. The developers, and maybe you are one of them @niksan29 , have implemented a model for us, from which they must have had documents and perhaps also received technical support. The quality is still exemplary. What is not is not possible and actually it was only about what can and should you actually fly with the Dash. We have clarified that too, I think, and don't forget, we're here in the flight simulator at home, everything is fine. So if it sounded like criticism in the discussions, that's not the case. The Majestics Dash is still one of the best planes for the simulator.
Since the steep approach functionality is an "option" there is supporting data from the aircraft manufacturer which denotes how the system is implemented. It's easy to add a switch but what underlying paraments are affected and or must be in place which that switch is activated. WE do not have access to this technical information thus the reason it is not implemented. Granted the system on the outside based on the manual states what it does which is simply disabling certain functions of the EGPWS.
The same applies to FMS functionality as previously mentioned with respect to the fact that we modeled the FMS based on what we had available at the time. We have already put a lot of work into its development and actually had to re-write a majority of its code for the 64-bit platform. What other developers have done bears no relevance on what we do. If we find it feasible to improve on this feature we'll do so time permitting, and hopefully, we may be able to get some assistance from the Navigraph team on the issues of concern.
As always we welcome discussions on items/topics, there are times that we do not participate but we do read the topics to get a feel for their importance. Many of which are informative and interesting as different perspectives are shared based on everyone's interaction and knowledge of the respective real-world systems and procedures.
Cheers
THX @kroswynd
@FraPre
@kroswynd
yes, it really looks like a steep approach is just:
@kroswynd
I really don't know how they can help you because their nav base is the same for everyone tools and aircraft, it's just a different format, but the data is identical.
let's hope you will have(with time) the necessary documentation and will be able to add this function(steep) as well as improve the VNAV system
P.S
and there is no criticism and claims to you, this is just what we noticed and are discussing it