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martyr

Domestic Flights, IFR or VFR? Visual Approach?

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Hello everyone,

I am trying to "simulate" air taxi service between tropical islands.

This is short and great way to flight :)

 

However, i would like to make a proper and well-planned flight, since i am going to do it online on IVAO.

My preferred A/C is DHC-6 Twin Otter.

My departure is FSIA Mahe Island and arrival is FSPP Praslin.

Well dep/arr is vicinity of Seychelles. There are many islands with small airports and airfields.

 

My questions are below (i know there are too many!)

 

1- Should i go for IFR or VFR? Weather is almost always clear, wind is calm and visibility is good near Seychelles. How to decide?

2- How to select a cruising altitude for VFR? I read AIP/AIS of Seychelles, seems like its provide all information needed. Is that right way to start planning?

3- Is that possible to use ILS approach on VFR flight plan? Is this a VFR -> IFR or VFR -> VFR flight?

4- I am going to do same flight with Cessna 172. It does have all necessary equipment for IFR as far i know, so i can go for IFR, right?

5- I am little bit confused about terms IFR, VFR and Visual.

Does Visual approach changes flightplan to VFR? As far i know, Visual Approach is a part of IFR. So flightplan should be stay same, right?

Why and when Visual Approach needed? Is this possible to do Visual Approach on ILS runway? (Ignoring ILS and doing whole thing visually)

So is this possible to do Visual Approach in VFR flight?

What's the equivalent of Visual Approach in VFR?

Or am i getting this completely wrong?

As i understand, Viisual Approach is the VFR's itself. Because whole thing visual. So how about opposite scenerio?

Can i use ILS approach on VFR? And does it changes flightplan to VFR->IFR?

 

 

Any help and idea would be great.

Thank you all.

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Let's try and make this simple, in order to avoid any further confusion...

 

For the flight you want to make, VFR (Visual Flight Rules) will be fine. The only time you'll need to consider IFR (Instrument Flight Rules) is when the Weather isn't clear, or the haze will not permit you to clearly see either the Horizon or the Runway.

 

You can choose any Altitude you wish; for a flight this short, stay around 3,000 ft. No need to subject your pax to a Vomit Comet ride!  :P

 

You can make a Visual Approach without using the ILS; you'll be using the PAPI lights next to the Runway instead.

 

Personally, I'll use the ILS (if it's available) on a Visual Approach, as an additional aid to get Glide Slope information. The more Info you have, the better off you'll be.

 

Hope this helps; more will chime in, for sure.

 

Alan  :smile:


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A "visual approach" is like a normal approach/landing when you're flying VFR- however, it can be conducted under the auspices of an IFR flight plan. Even if I've flown the flight  point A to point B in instrument conditions, clouds, fog, whatever- but I pop out in very good conditions at my destination and see the airport, I can tell the controller I've got the "field in sight." I'll remain on my flight plan, but conduct an approach and landing myself. Sometimes- you might not even have the airport in sight, but rather traffic to follow, and that's fine too. It just allows ATC to release you from their guidance a little earlier, and makes you able to possibly fly more efficiently. If however you "go missed," you can still return to ATC- on your original flight plan, and either be guided for a subsequent instrument approach, or to your alternate.

 

For your type of operation, I'd say flying VFR is just fine. Under IFR, you'd have to file a flight plan with airways- ATC basically would have much more control of your flying (read: more $$ for the operator). VFR you can (basically) type in the "direct to" destination and go on your merry way. 

 

Where this gets interesting is in busy corridors such as Washington DC - New York, or out in the Hawaiian islands- where there is a lot of traffic types (IFR/VFR) mixing. I always used to get annoyed at the dimwit flying at 12,500 in the summer- while I was at 13,000ft trying to dodge buildups. He was perfectly "legal" to be there, but of course sets off my TCAS and causes another distraction. 


Brendan R, KDXR PHNL KJFK

Type rated: SF34 / DH8 (Q400) / DC9 717 MD-88/ B767 (CFI/II/MEI/ATP)

Majestic Software Q400 Beta Team / Pilot Consultant / Twitter @violinvelocity

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(Reproduced by request from the Flight Planning forum):

 

 


1- Should i go for IFR or VFR? Weather is always clear, calm wind and good visibility near Seychelles. How to decide?

 

Depends on your risk threshold!

 

The main advantage of flying IFR is that you can fly in controlled airspace and thus benefit from the safety of a known traffic environment: in most classes of CAS, every aircraft that enters will have to be speaking to/identified by air traffic control: plus, responsibility for separating IFR traffic from both VFR and other IFR traffic rests with the controller (though, of course, the PIC/see and avoid remains the final defence!). If you are VFR, you will either have to remain outside controlled airspace or negotiate a clearance through (which may or may not be forthcoming). Outside CAS it is "bandit country" -- there is no requirement for other aircraft to be talking to anybody, have their transponder switched on (=no TCAS).... it really is "see and avoid".

 

For this reason, most commercial operators prefer (and, indeed, their insurers may require) to fly on an IFR plan: it's significantly safer.

 

 

 


2- How to select a cruising altitude for VFR?

 

I'm not familiar with the Seychelles AIP, but there is normally a form of either semi-circular (east/west) or quadrantral (different levels for traffic going NE/SE/NW/SW). Usually a VFR cruising level would be an odd or even level (dependent on direction of flight) +500ft. However, see above: outside CAS you are in bandit country and in any event you must remain in VMC (which will be defined by local regulations: essentially the very minimum requirement is clear of cloud and in sight of the surface, but there are usually minimum in-flight visibility requirements and once you start going higher you usually need to be ~1000ft vertically and ~1500m horizontally separated from any cloud).

 

 

 


3- Is that possible to use ILS approach on VFR flight plan? Is this a VFR -> IFR or VFR -> VFR flight?

 

There is no reason why you can't tune the ILS up and follow it if you know how to use it. However, ATC will not (may not) vector VFR flights and you will not be offered an instrument approach procedure if you are on a VFR plan (it will be assumed if you are on a VFR flight plan that you don't have an IR). However, if you want to tune it and use it as a backup to your visual, I see no problem with that.

 

 

 


4- I am going to do same flight with Cessna 172. It does have all necessary equipment for IFR as far i know, am i right?

The equipment required depends on the regulations in each country: the UK requirement is laid out in Schedule 5 of the Air Navigation Order, the Seychelles will presumably have a similar document, but yes. Generally speaking you need a radio, transponder, radio navigation kit (i.e. VOR/ADF), turn and slip indicator, ADI etc: the C172 has all of these.

 

 

 


5- I am little bit confused about terms IFR, VFR and Visual. Even if i fly with B738, i am going to land "visually", does it means that flightplan changes to VFR?

 

Don't confuse the type of approach with the flight rules.

 

You can fly a visual approach under IFR: accepting or flying a visual approach does not change your flightplan to VFR. However, you must have adequate visual references to fly the visual approach (i.e. VMC).

 

IFR = Instrument Flight Rules. You require an Instrument Rating, but this means you can fly in IMC (Instrument Meteorological Conditions -- i.e. clouds/poor/nil visibility) if necessary. You can do this because you instrument training prepares you to fly by sole reference to the instruments, and by flying in controlled airspace (though you can fly IFR outside controlled airspace) ATC does the "seeing and avoiding" for you with radar (or other methods of separation).

 

For this reason, you must follow all ATC instructions and ATC may vector you (i.e. give you headings and altitudes to fly). They can do so because it doesn't matter if they vector you in to a cloud: they know where the other aircraft are and you are capable of flying without visual references. ATC is responsible for your terrain clearance whilst they are vectoring you, and instrument procedures are designed to give you appropriate terrain clearance if you follow them correctly.

 

VFR = Visual Flight Rules. You must remain in VMC (Visual Meteorological Conditions) and you are responsible for both separation from other aircraft and from terrain. You must also plan to fly outside of controlled airspace, though you may be permitted to transit class B/C/D if traffic conditions permit.

 

Because you must remain in VMC, ATC may not issue you radar vectors (they might take you in to a cloud), and they will not offer you an instrument approach procedure. They may, however, ask you to follow a certain route, remain east/west/south/north of a particular point, route via a particular ground feature, or remain above or below a certain altitude in order to help deconflict you from other (i.e. IFR) flights.

 

A visual approach is just that: an approach flown using primarily visual references, instead of with primary reference to a published instrument procedure such as an ILS. You may carry out such an approach on both IFR and VFR flight plans, and in any aircraft type from a C172 to an A380.


Simon Kelsey

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Thank you all!

It's more clear now.

Well i was definitely mixing flight rules and approaches but i got the difference now.

 

Another question

1- Right now i have to operate this flight at night and weather is bad at the moment.

I am going for IFR for sure. How about cruising altitude?

Is there any "minimum" altitude for IFR? Should i have to read AIP to determine this?

 

BTW, current metar of FSIA (FSIA 251900Z 12010KT 9999 FEW015CB SCT017 29/25 Q1012

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Well, just completed the flight between FSIA-FSPP.

I can tell it was really hard and struggling because of current weather. Amazing experience.

If you are able to make short flight, go for same route right now :)

I have filled my flightplan as FL60, however, it was impossible to keep aircraft cruising altitude.

However, landed safely :)

It was hard because no a/p involved and DHC-6's a/p is really basic one.

Again, this route is highly recommended right now a short and challenging flight.

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How about cruising altitude?
Is there any "minimum" altitude for IFR?

 

IFR flights generally use even levels westbound and odd levels eastbound (though some countries operate a north/south system depending on the direction the main route structure).

 

There are a number of minimum altitudes applicable to IFR flights:

 

MEA (Minimum Enroute Altitude) is the minimum altitude on an airway that guarantees navaid reception

MSA (Minimum Safe Altitude) may be below this and represents an ultimate lower limit that will keep you clear of obstacles and terrain if you stay within the lateral confines of the airway. Also published on approach charts to represent the minimum safe altitude in various sectors around the airfield or a nearby navaid: you may not descend below MSA unless you are following a published instrument approach procedure.

Grid MORA (Minimum Off Route Altitude) is published for each grid square on the chart and represents the minimum altitude that will keep you clear of obstacles and terrain if you are not flying on an airway

 

If you are flying airways, they will be defined vertically as well as laterally: they will have lower limits below which you may be tracking along the course of the airway but not actually within the airway itself (i.e. you may not be in controlled airspace).


Simon Kelsey

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Thank you skelsey,

I can understand even/odd levels, that's how i am flying on normal routes actually.

But this route is so short (23 nm).

Seychelles AIP (http://www.scaa.sc/files/AIP%20Seychelles.pdf) explains alot of things.

If you can take a look at page 90, there is table.

Should i reference it for cruising flight level? And then MSA of the airport, right?

FSIA has MSA 4500ft, 25nm radius.

 

So i should pick an altitude greater than 4500ft to stay in MSA, and FL60 or FL70 for my cruising altitude. May you confirm?

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Hello again,

Please ignore previous message :)

I got it now.

 

Thak you skelsey, ViperPilot and bjratchf

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Just to nitpick, there's no such thing as FL60 or FL70.

 

A controller would laugh at you if you said that in real life or get annoyed.

 

Flight levels begin at 18000 feet. Below you just say 6000 feet.

 

Also, if you are simulating an air-taxi service, file IFR. That's typically what you see. It's a misconception that you only file IFR in bad weather. You also DO NOT have to fly airways IFR. You can file to waypoints, fixes, etc. if it gives you a more direct route.

 

Also, someone mentioned Clearence from clouds when VFR. That varies.

 

Class G is simply 1 mile vis and clear of clouds. Class E is 3 miles vis, 500 below, 1000 above, 2000 horizontally. Above 10000 feet it goes to 5 miles vis, 1000 below, 1000 above, 1 mile hirizontally. At 18000, you must be IFR.

 

As far as using an ILS while VFR, you'd only do that if you are doing a practice approach. Otherwise, you fly a traffic pattern.

 

If you want to fly straight in on an ILS while VFR you'd request or announce (if on CTAF) a practice approach and your location. The tower can deny it but if there's no tower just see and avoid. Guys in the pattern will usually extend their downwind to accommodate if you are calling a 3 mile and 1 mile final.

 

Of course, you do have jackasses who fly 5 mile straight ins VFR not doing a practice approach and jump the pattern.

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There are plenty of places in the world where you will say FL060. Transition altitudes are unique to each country. It just so happens that 18000 was chosen for the US. It can be different in other places.

 

Air taxis, charters, etc. do plenty of VFR flying. They may have IFR flightplans filed, but whether or not that gets activated depends on the pilot. They are just as likely to just takeoff vfr if the weather permits.

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There are plenty of places in the world where you will say FL060. Transition altitudes are unique to each country. It just so happens that 18000 was chosen for the US. It can be different in other places.

 

Air taxis, charters, etc. do plenty of VFR flying. They may have IFR flightplans filed, but whether or not that gets activated depends on the pilot. They are just as likely to just takeoff vfr if the weather permits.

I've flown them in three countries outside the US. They all filed IFR. Niger required it in fact.

 

I can't speak for every island jumper out there though.

 

Filing IFR is just easier in the US if you are going somewhere. No worries about airspace, traffic is managed, frequency changes are given, no worries about clouds or getting through a layer, the safety aspects, etc. If I don't do it, then I'm getting FF at least unless it's a very short trip.

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Not true.

 

Eh?

 

I can confirm, with absolute certainty, that FL60, FL70 and a whole host of other flight levels exist here in the UK, where the transition altitude varies but in Class G is 3000ft (6000ft in the London TMA, various other levels in other TMAs but between 3000 and 6000).

 

The same is true across Europe (where TAs vary but are often below 10,000) and indeed the rest of the world.

 

The TA in the Seychelles is 3500ft (apart from within 25NM of FSIA, where it is 4500ft) so FL60 most certainly exists there. If you want proof, see paragraph 1.7.2 of the official, real-world AIP: http://www.scaa.sc/files/AIP%20AMDT%200114%20ENR.pdf

 

Much of the rest of your post is also relevant only to the USA: UK VFR minima are certainly different to those you have stated, and though I'm not an expert on other countries' VFR minima I would expect them to potentially differ from both UK and FAA rules. Likewise, our upper airspace outside of airways is Class C, so you most certainly can fly VFR above FL180 in the UK (and the military often do).

 

Whilst it would be nice if the rules were harmonised across the world, the truth is that there are often significant differences between countries. The only solution is to check the local documentation of the country you are operating in.


Simon Kelsey

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Eh?

 

I can confirm, with absolute certainty, that FL60, FL70 and a whole host of other flight levels exist here in the UK, where the transition altitude varies but in Class G is 3000ft (6000ft in the London TMA, various other levels in other TMAs but between 3000 and 6000).

 

The same is true across Europe (where TAs vary but are often below 10,000) and indeed the rest of the world.

 

The TA in the Seychelles is 3500ft (apart from within 25NM of FSIA, where it is 4500ft) so FL60 most certainly exists there. If you want proof, see paragraph 1.7.2 of the official, real-world AIP:

 

Much of the rest of your post is also relevant only to the USA: UK VFR minima are certainly different to those you have stated, and though I'm not an expert on other countries' VFR minima I would expect them to potentially differ from both UK and FAA rules. Likewise, our upper airspace outside of airways is Class C, so you most certainly can fly VFR above FL180 (and the military often do).

 

Whilst it would be nice if the rules were harmonised across the world, the truth is that there are often significant differences between countries. The only solution is to check the local documentation of the country you are operating in.

I literally edited that I misread 20 seconds later.

 

Sorry I made you type all that up.

 

Class C in the US is airport airspace along with Class D and B. Just about everything above 1200agl is Class E here. Class G above is getting harder and harder to find. Can't fly VFR here in Class A.

 

Crazy how much things differ. I admittedly will answer a question sometimes with a US mindset because that's where I fly in real life.

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No worries!


Simon Kelsey

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