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PeterDa

Winds aloft predictions for lat/long waypoints

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I leave ASN completely out of the loop. I load the program, and then manage everything with PFPX. I look at them as comparisons of real world entities

 

 

If you read my post #5 you will see that on several occasions PFPX had the wrong METAR data for the departure airport. Right time - wrong day. If that was incorrect I would assume the winds aloft forecast was also incorrect. On one occasion at KIAD, PFPX didn't agree with the AWC-ADDS METAR. I restarted PFPX twice and twice it had the same incorrect METAR. On the third restart I loaded ASN first and then PFPX and the METAR was correct. I don't think ASN can be left out of the loop.

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If you read my post #5 you will see that on several occasions PFPX had the wrong METAR data for the departure airport. Right time - wrong day. If that was incorrect I would assume the winds aloft forecast was also incorrect. On one occasion at KIAD, PFPX didn't agree with the AWC-ADDS METAR. I restarted PFPX twice and twice it had the same incorrect METAR. On the third restart I loaded ASN first and then PFPX and the METAR was correct. I don't think ASN can be left out of the loop.

 

I'm not convinced.  There are other contingencies within PFPX that most people forget about.  The first one - and most importantly - is the scheduled time of departure.  If that time is not coinciding with when you're actually leaving in the sim, and in the real world, your data is going to be off.

 

Example:

You're planning to leave at 16:00Z in PFPX.

You're actually departing at 16:00Z real world time.

 

Those are HUGE.  If you get those out of sync (most people forget the PFPX date/time), then PFPX is going to be out of sync.  Unfortunately, there's nothing they can do about that if the user is giving it bad data.

 

I have a feeling that the reason it "worked" with ASN, was that ASN doesn't come in timestamped.  PFPX just takes ASN's depiction as "current" however it's being brought in.  If my PFPX flight date is set as 4 years ago, it won't flinch at the data that's being brought in current as of a minute ago.  If you tried that with NWS data, it's going to try to find the NWS for that flight date and time.

 

Powerful tools require powerful attention.  If you don't pay attention, you're going to get bitten.  I have a couple times, and I did exactly as you stated: push ASN weather and it "resolved."  I realized later that it wasn't the program's problem, though; it was that I had planned the flight 2 days prior, intended on flying it at that moment, and then got sidetracked for a few days before I got to flying it in the end, but forgot to re-set the departure date/time to the current date/time.


Kyle Rodgers

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It is quite simple. When you load ASN it downloads the weather which it saves as a text file. This text file does not deleted when you stop ASN, it stays there with the details of the last downloaded weather.

 

When you load PFPX, provided you have it set to read ASN weather, then it will load the ASN weather text file. This is the file that PFPX will plan your flight and provide weather for.

 

So lets say for example you fly on the Monday with ASN. On Wednesday you decide that you want to fly again. You load PFPX without running ASN, it reads the weather file from Monday, because this is the last time it was run. PFPX then plans your flight with Mondays weather. You then run ASN and it downloads Wednesdays weather. You now have ASN giving you Wednesdays weather and PFPX giving you Mondays weather. This is why you have different METARS.

 

Now if you load ASN first, let it download the weather and save an updated weather file. You can then load PFPX which will read the updated weather file and be able to plan the flight with the correct weather.

 

Now what Kyle is talking about comes from the fact that ASN can predict weather hours in advance from the different weather information around the world, a bit like when you watch your local weather channel and the weather predicts a day of sun. PFPX allows you to plan a flight for a different time of departure, in which case it will read the ASN weather for that time. So if you plan for a 3pm departure, but load up FSX and depart at 12pm then FSX and ASN will give you weather for 12pm, but PFPX will give you weather for 3pm, so you have to make sure that these time match.

 

Anyway, weather details given by the dispatcher is just for advice only, not an exact figure. just as your local weather man predicts a nice day, you plan a day at the beach only to find that the heavens have opened and it rains all day. Nobody can predict the weather so even though the dispatcher plans your flight, gives you weather with runways to take off and land, it may change. Take PFPX information and use it for information but take the weather from ASN. Just make sure that ASN is loaded before PFPX.

 

If you want to make it more realistic then don't load exact fuels. Ground staff cannot always load fuel to the exact measurements, in the flight sim world we can. Or you could pretend that you are delayed due to passengers not turning up on time, again it is all too easy to look at the clock and leave, not so in the real world.

 

Sometimes I like to pretend that I am flying for a budget airline and land and hour away from my actual destination, telling my passengers that we landed there for cheaper fuel and for them to get the bus the rest of the way.

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If you want to make it more realistic then don't load exact fuels. Ground staff cannot always load fuel to the exact measurements, in the flight sim world we can. Or you could pretend that you are delayed due to passengers not turning up on time, again it is all too easy to look at the clock and leave, not so in the real world.

 

Eh...not quite true.  The trucks out on the ramp can get pretty precise.  The airlines order X amount of gallons and they will get X amount of gallons.  They are not quite forgiving on over-pumps or mis-pumps because they have their flights down to a science:

IAD-ORD should be X amount of fuel, which gives us Y room for passengers.  If you mess that up as a fueler, you're going to get the company in hot water, and you're going to get called into the office for that one.

 

Many aircraft actually have a fuel service panel where you dial in the amount of fuel you're going to upload and it'll shut the fuel off once it's received that value (even aircraft as "small" as Citations have this).  Here's the panel for the NG (note the author references a "quantity preset facility" - this is what I'm referring to): http://www.b737.org.uk/refuelpanel.htm

 

It's not an issue of not loading exact fuel for realism:

It's an issue of not getting too worked up about forecast data (enroute winds).  Plan it on known data.  Accommodate differences in forecast versus actual with your 'contingency' or 'extra' values.


Kyle Rodgers

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My apologies. I assumed that it was the same as fuelling the car, no matter how I try to get exact, I always go slightly over. Still I am sure that on occasion there have been instances that things have not gone quite to plan.

 

But I agree, plan your flight with what you would know in real life and live with whatever you get.

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My apologies. I assumed that it was the same as fuelling the car, no matter how I try to get exact, I always go slightly over. Still I am sure that on occasion there have been instances that things have not gone quite to plan.

 

But I agree, plan your flight with what you would know in real life and live with whatever you get.

 

No worries.  People only know what they experience, or know first-hand.  Unless you've been out on the ramp fueling planes, or have actually stood there and watched it on the ramp, there's no real way you'd know.

 

Think of it like the inverse of what you see if you use cash at a pump:

Ask for $20-worth of gas, and the attendant will set the shutoff at $20.  As soon as you hit that $20: *click* it's done.  No more, no less.

 

Same thing, but instead of a dollar amount, it's quantity.


Kyle Rodgers

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Living in the UK we don't have that. At the pumps here you fill up and then pay. Cash or card makes no difference. If you end up not having cash after filling by mistake, then as long as you leave something as a deposit the you can go back later. I normally leave my wife, then go back a week later.

 

Although I do know what you mean. When I was younger we went to the states for a holiday. May parents forgot how big the states was compared to the UK and landed in New York and drove to Disney World and back. I remember him pulling into a station and standing for ages wondering why the pump wasn't started, until he found out that he had to pay first.

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Living in the UK we don't have that. At the pumps here you fill up and then pay. Cash or card makes no difference. If you end up not having cash after filling by mistake, then as long as you leave something as a deposit the you can go back later. I normally leave my wife, then go back a week later.

 

Although I do know what you mean. When I was younger we went to the states for a holiday. May parents forgot how big the states was compared to the UK and landed in New York and drove to Disney World and back. I remember him pulling into a station and standing for ages wondering why the pump wasn't started, until he found out that he had to pay first.

 

It wasn't like it is now when I was a kid / starting to drive.  Drive-offs weren't a huge problem until gas prices went up a whole bunch in the early 2000s (and even then, were still pretty cheap in comparison to the rest of the world - still are in many cases).  As the problem increased, places started making you pay in advance.


Kyle Rodgers

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Powerful tools require powerful attention. If you don't pay attention, you're going to get bitten. I have a couple times, and I did exactly as you stated: push ASN weather and it "resolved." I realized later that it wasn't the program's problem, though; it was that I had planned the flight 2 days prior, intended on flying it at that moment, and then got sidetracked for a few days before I got to flying it in the end, but forgot to re-set the departure date/time to the current date/time.

 

 

Kyle

This whole sequence of events took place at Dulles over period of 30-45 minutes on the same day. Start PFPX, restart PFFX twice, load ASN, and restart PFPX. I know you mentioned ASN was not timestamped and this effected the information PFPX used. I didn't know there was any interaction between the two programs. After loading ASN and restarting PFPX which then showed the correct METAR, the whole thing made no sense to me. Is there someway that they pass information back and forth?

 

Anyway, this is the last post in this thread. All of this involves the NGX not the T7.

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Sequence of events should be as follows.

 

1. Load ASN, allow weather to download and ASN go to idle.

 

2. Load PFPX and then plan flight. Note down departure date/time and ensure is correct.

 

3. Export flight plan for FSX if needed, Aircraft if needed and PMDG 777 if flying the PMDG 777.

 

4. If you want and have all the information of your flight plan then at this stage you can close PFPX, or you can leave it running.

 

5. Load FSX and set it to coincide with your PFPX flight plan.

 

At this point ASN will set the weather for the aircraft position to the weather data it has for the aircraft position. You can load your plan into if you want to, but be aware that it save a new PMDG 777 weather file based on the information at that time. If ASN downloads new weather between planning your flight and loading that plan in ASN then there may be a slight difference.

 

6. Fly the plan based on the possible changing conditions compared to the prediction and enjoy.

 

Also make sure that if you are using ASN, that PFPX is set to read the ASN weather file. Different services may give slightly different interpretations and predictions.

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Again - there is ZERO dependency on ASN unless you ABSOLUTELY want it, and tell PFPX to use data from it and not real world sources.

 

Don't add in layers of complexity:

Let ASN do its thing.

Let PFPX pull from its sources.

 

This will result in the most realistic situation out there:

Real world data sources do not have 100% access to weather information (you need only look as far as wind/temp charts - they only get pulled at selected altitudes, and at sites hundreds of miles apart).  Thinking of the weather as ASN, and PFPX as any dispatch software out there, "ASN" and "PFPX" in the real world have no direct connection.  "ASN" is "connected" to "PFPX" via the various weather service providers.

 

Load the two programs whenever, wherever, and however you want.  There needs to be no procedure, and there needs to be no special attention paid (unless you're linking them for some reason).

 

 

 

 

The only reason I brought it up earlier was to say that national weather service data that is pulled will depend on what date/time you tell PFPX the flight is occurring.  What is meant by this is that, if you tell it the flight is happening in the future, it will be pulling forecast data to assist in the planning.  If you tell it that it's in the past, it will use past data (and from what I can tell, notify you that there's no forecast data for that time period, but this would make sense, sense you don't forecast historical information...it's already happened).  NWS has forecast and historical data.  ASN provides data without timestamps to the programs that access it.  What I mean by this is if you load ASN to provide weather data from 4 years ago, PFPX will treat is as current, and the sim will treat it as current.  If you load "live" information from ASN, PFPX will treat it as current, and the sim will treat it as current.  When you're loading ASN weather into PFPX and tell PFPX that the flight date is 4 years ago, it won't force ASN to find data 4 years ago (it would with the NWS, from what I can tell).  It takes whatever ASN is broadcasting and uses that.

 

Clear as mud?


Kyle Rodgers

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