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Adding Current AIRAC Approaches to FS2004 and FSX

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223
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us-idaho
I am currently in the middle of a huge undertaking that at times I wish I had not started, but cannot let go of. I am using ADE9X to update the approaches at many Alaskan airports to reflect the current AIRAC cycle waypoints.

Creating the waypoints is certainly not an issue. I create the "missing" waypoints in the "Approach Mode" and then connect them with the various legs available in ADE9X. Not sure where I got it, but I have a printed page with a description of what each leg type does. For the most part I have been quite successful and my list of airports in Alaska with current runway numbering, additional runways where applicable, deleted or closed runways when necessary, and current AIRAC approaches has grown to 62 fields.

However, in the process I have come to some "stumpers". I will try to use Barter Island as my example, specifically the RNAV approach to runway 7, but some of the questions are from other fields and after doing 62 of them it is difficult to remember which field presented which issues, so please bear with me.

Concerning Barter Island (PABA) and many if not all simple RNAV approaches. The approach resembles a "T" in design. The approach runs from HULKS (the Initial Fix-IF) to IYAPI to KNARS to JESOT. JESOT is the Missed Approach (MAP) point. The MAP proceeds to "Climb straight ahead to 2,000 feet" direct to DEVKE and hold at DEVKE. There are three Initial Approach Fixes (IAF) listed on the chart; KOKBE, HULKS (also the IF remember), and LEPGE. Using existing stock airport as a "guide" of sorts I have realized the IAFs are typically considered as Transitions in "Approach Mode". I have added all these waypoints as Terminal Waypoints since none existed in either FSX or FS2004. KOKBE is to the North and LEPGE to the South of HULKS.

Question 1...There is a 4 nm hold at HULKS inbound on 071 degrees and right hand turns at 2,000 feet. After adding the waypoints, the approach, and the missed approach legs, I started adding the transitions, beginning with the one at HULKS. I created an "IF" leg at HULKS followed by an "HA" leg at HULKS. I then added the LEPGE and KOKBE Transitions, both beginning with an "IF" followed by a "TF" leg to HULKS. Do I need to also add an "HA" leg to each of these two Transitions or will they track to HULKS and fly the "HA" leg at HULKS? And a secondary question would be where does the hold belong in the first place? Is it the beginning of the approach or the end of the transition?

Question 2...I cannot recall which airport it was at, but in an VORDME approach I built the VOR was very close and left of the runway. The missed approach on the chart looked like a figure eight that overflew the VOR and ended up back at the VOR. I think the description of the MAP was something like "Right turn to intercept the 059 degree DME radial outbound , climbing left turn to 2,000 feet, re-intercept the 059 Radial inbound to the VOR and hold at the VOR. I do not recall the exact leg types I used, but I know they did not look like the perfect figure eight in the diagram. I believe I used a "CR" to reach the 059 radial outbound, a "CA" to reach the MAP altitude and turn to the left (but it only lets me turn 180 degrees, not back to the radial), another "CR" to get back to the 059 radial, a "DF" to the VOR, and an "HM" to terminate the MAP in a hold. Looks ugly in sim, but accomplishes what I needed to do.

Question 3...Really this could be a tertiary to question 1 also. I noticed some of the default Transitions resembled that same similar "T" of a simple RNAV approach, with the center fix being an IF/IAF and the left and right fixes being just IAFs. In many cases the left and right fixes had "IF" legs, but the center IF/IAF fix did not. This always resulted on the screen as a red arrow poointing due north. Remember, these are default "when FS2004 and FSX were created" transitions. I always begin my created Transitions with an "IF", even the IF/IAF ones, but I got to thinking, by doing so am I forcing FSX or FS2004 aircraft to fly two transitions when using those type approaches? Is that why the center "default" fixes don't have an "IF" leg? If so, what does that North-pointed red area do if I try to follow the approach with the default GPS?

I am sure I'll have more questions as this project continues, but for now I'll leave it here. A tutorial on making approaches, missed approaches, and transitions would help immensely, but I have yet to find a good one that answers any "detailed" questions.

Randy
 
Messages
223
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us-idaho
I have another question. The sheet I have lists a CA as Course to Altitude, but doesn't specify if that altitude is MSL or AGL. So that is my question.

As a secondary, I am working on a Missed Approach that has two consecutive climbs listed. The first is on the runway heading to 2,000 feet and the second is a climbing turn to 2,200 feet, yet the second climb leg appears longer than the first. It should only be an actual difference of 200 feet above the previous CA to reach 2200, so a much shorter leg, regardless of whether the "A" is AGL or MSL. This leads me to believe I have really put in a climb to 4,200 feet.

Randy
 
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983
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us-florida
I would say that in general the altitudes are in MSL. It would probably specify if it were AGL.

Ed
 
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223
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us-idaho
Thanks for that Ed. I suspected it was MSL, but was not sure. Still not.

Doesn't explain why a CA leg to 2200 is longer than the CA leg to 2000 it follows. Should be much shorter since I should already be at 2,000 feet. Perhaps the CA altitude entry is just number of feet to climb regardless of MSL. If that is the case I will have to take the altitude of the fields ARP and do a CA to get to the MSL altitude I want in the MAP. For instance, if the ARP altitude is 2,323' and I want to do a CA to 4,000 MSL I would make the CA altitude 1,677 feet, with additional CA altitudes that are only the difference between 4,000 MSL and the new altitude. That seems too task intensive. I doubt Jon designed ADE that way, sooooo.........

That takes me back to why a CA to 2200 after a CA to 2000 is longer than the 2000 leg?

Randy
 
Messages
777
Country
unitedstates
Question 1- if you look at the approach plate you will see on the lines from LEPGE and KOKBE that it says NoPT. This indicates that you would turn inbound at HULKS when using those transitions.

The hold at HULKS would only be used when HULKS is the IAF and therefore would only need to be in your HULKS transition.

You would only use the HULKS transition if you were coming from the east and/or needed to use the hold to burn off some extra altitude.

Question 2- If you can remember what airport, so I can see the plate, it would help.

Question 3- IF is more of a fix than a leg. A point in space, if you will. Each approach has an IF and each transition to that approach also needs an IF.

When you look at a plate and see the IF, that will be the IF for your approach. When you look at a plate and see an IAF, that will be the IF for your transition.

If you are asking if there are errors in the default approaches, I would say yes, there are many approaches that are not quite up to snuff.

Also, all altitudes on approach plates (except in the minimums box) are MSL. Every airplane has an altimeter, very few have radar altimeters.

As for the difference in length of the climb to 2000 vs. the climb to 2200- it probably has to do with obstacle avoidance and the actual length of the legs is going to change from plane to plane as they have different ground speeds and climb rates. In other words, don't get too hung up on what you see in ADE and/or the GPS. What airport is this at?

cheers,
Lane
 
Messages
223
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us-idaho
Lane,

Thanks for the reply. I saw that and to be honest I always wondered why that comment was there as I saw no Procedural Turn on the plate. Please understand my idea of a PT was the narrowest of views, i.e., an outbound course from a fix then a left or right 180 degree turn back toward the airport. I can only assume that is not the only type of PT, as in this case the Hold is considered a PT and not to be flown from LEPGE or KOKBE. Thank you for that, but now I have a lot of corrected procedures to do :)

If you can remember what airport, so I can see the plate, it would help.

It was at Savoonga, PASA. Took me a while to find it again going through all the airports I dealt with. It was the VOR/DME 23 MAP. Open the PASA image to see my ADE image. You can see I did not even use a CR leg to accomplish the turns, even though that was the description of the MAP. Using CRs resulted in a very "ugly" MAP.

What airport is this at?

Couldn't find the exact airport. Found a similar example at PATQ. This one involves climb straight out to 1600 then climbing turn to 2000, yet the CA 2000 leg, which should only be 400' difference is longer than the 1600' leg. Again, see the attached image of my ADE shot.

Hope this better explains my questions.

Randy
 

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Messages
777
Country
unitedstates
Your PASA looks pretty close, if not exact. I think you are running into the coding limitations of the sim.

It is far easier to draw a missed approach on a plate (and fly it) than it is to code a sim that allows all of the possible combinations of maneuvers.

I am certainly not an expert and have several times run into problems with missed approaches.

I would be curious to know how the sim handles your missed approach if you let the GPS drive the autopilot all the way to the hold.

Obviously the pilot still has to provide vertical control, which is why I never got too hung up on altitudes. To fly that missed realistically in the sim you have to have the approach plate and control altitude.

I see what you mean about PATQ and the leg length. Again, Jon has tried to mimic what ADE draws to what you see in the GPS. That is a major undertaking as results are not always predictable, at least for me.

Predicting how to draw a full missed when aircraft performance can change where turns will happen is almost impossible.

Remember, aviation (especially sim design) is an art as much as it is a science.

Maybe someone else (Jim Vile?) has some more input.

cheers,
Lane
 
Messages
223
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us-idaho
Thanks for that reply Lane. On the PATQ MAP I ended up skipping the 1600 foot CA and put in CA to 2000 then "curved it back" toward the ATK NDB. The following DF leg actually formed an almost perfect tear drop hold entry pattern that, at least on paper, stayed well within the protected area of the hold.

One type of MAP that always gets me is an RNAV approach with a MAP or transition that involves a curved flightpath such as at PAFA and the RNAV-Z 20R approach. The MAP for that one flys a 22.9 nm arc between BOSGE and AKIKE. a straightline DF or TF between the two is only 8 nm and change, yet that is what I had to do since there is no fix to reference the curve from as in a DME Arc (AF) leg. In sim I'll have the chart to look at and just make a wider turn between the two, as you described in your post. Arcs also exist on the Transitions between two fixes and, again, I had to make them directs.

I've been using AirNav to get all my fix locations which has resulted in another "issue" several times. Going from a fix I added to one already in the default NavBase, especially the Waypoints as opposed to Terminal Waypoints, results in skewed headings from the charts because the stock fix is not in the correct geographical location. I usually move the Terminal Waypoints to the correct spot since they're airport-dependent, but definitely don't want to tamper with Waypoint locations since they are used by multiple airports and Airways.

Again, thanks for the help Lane. Can't wait to see if Jon or Jim chime in.

Randy
 
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