VFR vs IFR

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Firebird
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Re: VFR vs IFR

Post by Firebird »

There are some simple rules for flightplans.
VFR flights make you responsible for avoiding terrain, IFR ones will fly over or around it.
If you have a flight plan that is VFR and to fly at 1000', which you do, it will only fly at 1000' and will not avoid terrain hence the crashes.
Secondly, a flightplan MUST have at least two legs.
Also think of legs as separate entities. each leg has a departure and a arrival time.
If a leg has the TNG instruction then you MUST have a leg following it. That leg MUST have a departure time that is between 2-5 mins after the end of the TNG leg arrival time (we always say 3 mins to be safely in the middle of that window).
Try to avoid multiple TNG legs back to back as theses can cause problems.

A lot of people assume that an AI plane will do TNGs until the arrival time and then land there. This is not the case. Sometimes this works, sometimes it doesn't. It is best to assume that it won't and then put a landing leg after the TNG leg.
Golden rule is to always make TNG legs a pair with the second leg starting 3 mins after the end of the TNG leg and landing at the same destination airfield 15 mins after the start time of the second leg.
The obvious exception to this is if you want a plane to TNG at one place but land at another destination, then the arrival time at the final dest is dep time plus journey time.

Also if you have weekly plans if you have a leg that starts BEFORE the previous one finishes then the legs for the rest of the week never show up.

So going back to your original plan.
1. Your plan is VFR and at 1000' so yes it will fly into terrain.
2. The second leg departs before the first leg is complete and so is ignored.
3. The consequences of this mean that you do not have a second leg and therefore the TNG leg never stops.
Steve
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col1948
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Re: VFR vs IFR

Post by col1948 »

Hi Steve,
I think I understood what you said, I changed the plan so the aircraft took off from EGNR to do a TNG at EGGP then return to do a TNG at EGNR before landing, here is the plan:
AC#200,G-CESL,20%,24Hr,VFR,09:32:42,TNG09:56:36,030,R,0000,EGGP,10:19:59,TNG10:43:53,030,R,0000,EGNR

I also had Plan-G loaded and the aircraft climbed to 1060ft, contacted Liverpool EGGP, got told it had clearance to do the TNG then it turned left as you can see from the screenshot and kept going.
in the meantime an aircraft at EGGP was waiting to take off because the tower told it this TNG aircraft was on finals but as you can see it was far from finals.
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Greg
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Re: VFR vs IFR

Post by Greg »

Were you following the traffic with MRAI TrafficViewBoard?
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Re: VFR vs IFR

Post by col1948 »

Hi Greg, Yes I was, is that the problem?
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Re: VFR vs IFR

Post by Firebird »

Here is your flightplan:-
AC#200,G-CESL,20%,24Hr,VFR,09:32:42,TNG09:56:36,030,R,0000,EGGP,10:19:59,TNG10:43:53,030,R,0000,EGNR

The first error is that you have the arrival time at EGGP as 09:56 and the next leg beginning at 10:19. The second leg after a TNG leg HAS to be between 2-5 mins later.
The second thing is that you have two TNG legs together which is not advisable as sometimes they work and sometimes they do not.
The final thing is that you do not have a land leg after the last TNG leg. It will not land unless you do.

So, in a nutshell alter the dep time of the second leg, and the arrival time accordingly. Then add a third leg from EGNR to EGNR departing 2-5 mins after the arrival time of the second leg and lasting no more than 15mins, or you can do away with the need for a third leg if you remove the TNG from the second leg.

The third leg effect will terminate the TNG and land.
Steve
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Re: VFR vs IFR

Post by col1948 »

Hi Steve, It was your post which made me add the second TNG, I misunderstood you, sorry mate, I orriginally only had one TNG.

I'm at the moment watching it without using TVB, I am using Traffic Tool Box instead, so far the AC is performing well.
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Re: VFR vs IFR

Post by clickclickdoh »

col1948 wrote:... it took off, did a 180 turn then flew at 1036ft for nearly 50-60 miles then flew in to some hills.
So the VFR isn't working, it should have turned well before that I'm sure.
Expected behavior.
col1948 wrote:... got told it had clearance to do the TNG then it turned left as you can see from the screenshot and kept going.
in the meantime an aircraft at EGGP was waiting to take off because the tower told it this TNG aircraft was on finals but as you can see it was far from finals.
Also expected behavior if runway 09 was in use at the time.

Using third party programs to view VFR aircraft in flight will prevent them from turning base or final. They will continue on the downwind leg for ever.
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Re: VFR vs IFR

Post by col1948 »

Sorry for the delay in answering, I had company lol. So it seems all this time I was doing it right but it was TVB causing the problems.
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Re: VFR vs IFR

Post by col1948 »

Well the update: I used Traffic Tool Box to follow the ai aircraft. I didn't change the flight plan, in other words it had two sets of TNG's.
The first set it did three then landed at EGGP, waited 8-10 mins then took off.
It did five TNG's at EGNR then landed ok, so it worked using two sets of TNG's plus not using TVB to follow the ac.
Thanks for all your help guys, it is very much appreciated.
Col.
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