IMC in open FIR - classification?
Thread Starter
Join Date: Mar 2003
Location: UK
Posts: 437
Likes: 0
Received 0 Likes
on
0 Posts
IMC in open FIR - classification?
Scenario:
You take off from airfield A, in uncontrolled airspace, set course for airfield B, also in uncontrolled airspace.
Climb to say 2800ft on reg QNH. Being IMC rated, you plan to enter IMC. This infers that you are clearly no longer VFR, so conforming to IFR, albeit below FL030 on QNH. You decide to call for a RAS service.
My question is, when identifying yourself to the ATSU, you state that you are IFR, 2800ft requesting RAS, giving all other relevant details. Does this constitue an IFR flight plan as filed over RT, thereby enabling the ATSU to issue you with a radar service (RAS)? I am trying to clarify the rules in my head here. As I understand it, if you are IFR, the only time you need to pre-file a flight plan is if you will be IFR in controlled airspace (not class A if you have an IMC rating only) or can this also be passed over RT?
When cancelling IFR in uncontrolled, I also believe that the words "Request cancel IFR" have to be initiated by the pilot before the ATSU can downgrade to an FIS or RIS?
Any help much appreciated.
You take off from airfield A, in uncontrolled airspace, set course for airfield B, also in uncontrolled airspace.
Climb to say 2800ft on reg QNH. Being IMC rated, you plan to enter IMC. This infers that you are clearly no longer VFR, so conforming to IFR, albeit below FL030 on QNH. You decide to call for a RAS service.
My question is, when identifying yourself to the ATSU, you state that you are IFR, 2800ft requesting RAS, giving all other relevant details. Does this constitue an IFR flight plan as filed over RT, thereby enabling the ATSU to issue you with a radar service (RAS)? I am trying to clarify the rules in my head here. As I understand it, if you are IFR, the only time you need to pre-file a flight plan is if you will be IFR in controlled airspace (not class A if you have an IMC rating only) or can this also be passed over RT?
When cancelling IFR in uncontrolled, I also believe that the words "Request cancel IFR" have to be initiated by the pilot before the ATSU can downgrade to an FIS or RIS?
Any help much appreciated.
Join Date: Sep 2003
Location: UK,Twighlight Zone
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
IFR in class G is a state of mind. When you have passed the area giving you a Radar service they will either arrange a hand off to the next agency if possible otherwise you will get a Sqwauk 7000 go to enroute.
Thread Starter
Join Date: Mar 2003
Location: UK
Posts: 437
Likes: 0
Received 0 Likes
on
0 Posts
Agreed. But in your RT call for an RAS, you clearly have to state "IFR, 2800ft, flight condx IMC etc etc" That must also constitute a flight plan seeing as your are IFR, and out of contact with the surface?
Just trying to get my head around it. Thanks for the advice.
Just trying to get my head around it. Thanks for the advice.
Join Date: Oct 1999
Location: Anywhere
Posts: 2,212
Likes: 0
Received 0 Likes
on
0 Posts
My question is, when identifying yourself to the ATSU, you state that you are IFR, 2800ft requesting RAS, giving all other relevant details. Does this constitue an IFR flight plan as filed over RT, thereby enabling the ATSU to issue you with a radar service (RAS)?
Definition of a Flight Plan - "Details of a Flight or Portion of a Flight to enable the issuance of an ATC clearance".
IFR in Class 'G' does not require a clearance, so does not require a FPL, so this isn't technically a FPL. If you were crossing CAS at all and that was included in your request then it would
I am trying to clarify the rules in my head here. As I understand it, if you are IFR, the only time you need to pre-file a flight plan is if you will be IFR in controlled airspace (not class A if you have an IMC rating only) or can this also be passed over RT?
When cancelling IFR in uncontrolled, I also believe that the words "Request cancel IFR" have to be initiated by the pilot before the ATSU can downgrade to an FIS or RIS?
Join Date: Aug 2003
Location: Surrey
Posts: 1,217
Likes: 0
Received 0 Likes
on
0 Posts
Finals19,
To add to Bose's point.
1 - you can air file for IFR in controlled airspace. For instance when calling up Solent for a transit they may well ask if you want it IFR or VFR. When they read back 'G-AXYZ, cleared direct SAM then via R090, at 4000 ft IFR', you have just air filed your fllight plan in controlled airspace.
2 - With regard to downgrading from RAS to RIS/FIS, I believe the controller can do this for a number of reasons including radar performance, controller workload, your choice not to comply with a vector for separation, etc.
3 - I 'cancel IFR' is the phrase you use to downgrade to VFR when you are IFR in controlled airspace, this then means you are no longer receiving separation. As Bose said, IFR in Class G is just a state of mind.
To add to Bose's point.
1 - you can air file for IFR in controlled airspace. For instance when calling up Solent for a transit they may well ask if you want it IFR or VFR. When they read back 'G-AXYZ, cleared direct SAM then via R090, at 4000 ft IFR', you have just air filed your fllight plan in controlled airspace.
2 - With regard to downgrading from RAS to RIS/FIS, I believe the controller can do this for a number of reasons including radar performance, controller workload, your choice not to comply with a vector for separation, etc.
3 - I 'cancel IFR' is the phrase you use to downgrade to VFR when you are IFR in controlled airspace, this then means you are no longer receiving separation. As Bose said, IFR in Class G is just a state of mind.
Last edited by mm_flynn; 20th Mar 2007 at 12:14. Reason: spelling and noted this crossed with CM
Join Date: May 2001
Location: UK
Posts: 4,631
Likes: 0
Received 0 Likes
on
0 Posts
The only probably obvious comment I would add is that if you are receiving a service in class G, even if it is only a FIS, as others have said it is important to cancel IFR if you want to change your level without informing the unit you are working, otherwise they will assume you are remaining at the last reported level.
Join Date: Aug 2002
Location: Surrey, UK.
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
Is it?
Doesn't flying under the IFR mean that you are obeying rules such as remaining above MSA/SSA and that, above the transition altitude, you are flying quadrantals and flight levels?
Those are not "optional" or "recommended" under IFR are they? ...And if they are not optional that surely means IFR in G isn't just a "state of mind", doesn't it?
Doesn't flying under the IFR mean that you are obeying rules such as remaining above MSA/SSA and that, above the transition altitude, you are flying quadrantals and flight levels?
Those are not "optional" or "recommended" under IFR are they? ...And if they are not optional that surely means IFR in G isn't just a "state of mind", doesn't it?
Join Date: Sep 2003
Location: UK,Twighlight Zone
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
You may conforming to rules rustle but being IFR in in Class G is a personal choice. The discussion as around a flight plan not the IFR rules themselves. You can switch to IFR in Class G without telling a sole so I would say it eally is a state of mind!!
Join Date: Aug 2003
Location: Surrey
Posts: 1,217
Likes: 0
Received 0 Likes
on
0 Posts
Rustle,
When I last checked, operating VFR also was operating to rules. However, when you look at the rules for operating Class G/VMC, the differences betwen IFR and VFR are very subtle - with the most dramatic difference probably being that quadrantals and flight levels are recommended VFR best practice vs. IFR requirements.
Obviously when operating in IMC there is the fundamental difference that you can not possibly be flying VFR
.
When I last checked, operating VFR also was operating to rules. However, when you look at the rules for operating Class G/VMC, the differences betwen IFR and VFR are very subtle - with the most dramatic difference probably being that quadrantals and flight levels are recommended VFR best practice vs. IFR requirements.
Obviously when operating in IMC there is the fundamental difference that you can not possibly be flying VFR
.
Join Date: Oct 1999
Location: Anywhere
Posts: 2,212
Likes: 0
Received 0 Likes
on
0 Posts
However, when you look at the rules for operating Class G/VMC, the differences betwen IFR and VFR are very subtle - with the most dramatic difference probably being that quadrantals and flight levels are recommended VFR best practice vs. IFR requirements.
Join Date: Aug 2003
Location: Surrey
Posts: 1,217
Likes: 0
Received 0 Likes
on
0 Posts
Flight Rules an aircraft shall not fly at a height of less than 1000 feet above the highest
obstacle within a distance of 5 nautical miles of the aircraft unless:
(a) it is necessary for the aircraft to do so in order to take off or land;
(b) the aircraft is flying on a route notified for the purposes of this rule;
(c) the aircraft has been otherwise authorised by the competent authority; or
(d) the aircraft is flying at an altitude not exceeding 3000 feet above mean sea level
and remains clear of cloud and in sight of the surface.
obstacle within a distance of 5 nautical miles of the aircraft unless:
(a) it is necessary for the aircraft to do so in order to take off or land;
(b) the aircraft is flying on a route notified for the purposes of this rule;
(c) the aircraft has been otherwise authorised by the competent authority; or
(d) the aircraft is flying at an altitude not exceeding 3000 feet above mean sea level
and remains clear of cloud and in sight of the surface.
It is only in cases where you are flying above 3000 feet and the terrain/obstacle is above 2000 feet that it kicks in. (interesting that flying 500 feet above a 2490 hill in VMC complies with the IFR minimum height rule but flying 520 feet above it doesn't, also it appears that an IFR pilot can due this at 250 knots but a VFR pilot is limited to 140 knots)
Join Date: Oct 1999
Location: Anywhere
Posts: 2,212
Likes: 0
Received 0 Likes
on
0 Posts
And your point is?
The original poster was talking about flight in IMC - not what VMC get outs there were. I would suggest that the difference between Rule 29 (which is what you have posted here) and Rule 5 (which, for arguments sake, is the VFR minimum height rule) is still slightly more than subtle.
You have to draw the line somewhere. Sounds like an occasion where you'd be better off being VFR to me. You choose the rules you fly by according to the situation, taking into account all the factors involved. So - not a "state of mind", but a positive "choice"
But we're drifting off the original question here.
The original poster was talking about flight in IMC - not what VMC get outs there were. I would suggest that the difference between Rule 29 (which is what you have posted here) and Rule 5 (which, for arguments sake, is the VFR minimum height rule) is still slightly more than subtle.
(interesting that flying 500 feet above a 2490 hill in VMC complies with the IFR minimum height rule but flying 520 feet above it doesn't
But we're drifting off the original question here.
Join Date: Aug 2003
Location: Surrey
Posts: 1,217
Likes: 0
Received 0 Likes
on
0 Posts
Yes this has drifted off the original question, which was posed in the context of a flight into IMC.
The point I was making, which I suspect we partially agree on, is - IFR or VFR in Class G in VMC conditions is a choice of the pilot (i.e. a state of mind) with very little observable difference. In most cases a sensible VFR plan will also be IFR legal and compliance with the IFRs will also satisfy the VFRs (subject to being in VMC conditions). One of the few times this isn't true is when you are flying over terrain higher than 2000 ft AMSL and want to be less than 1000 feet above it - which probably isn't that sensible to begin with. This case also gives the 'odd feature' of having an altitude band which is not IFR legal but above and below that altitude are legal.
Because the IFRs and VFRs become effectively the same for most PPL/VMC operations in class G, it is simply the choice the pilot has made in his mind (a state of mind) that determines which rule set he is following.
The point I was making, which I suspect we partially agree on, is - IFR or VFR in Class G in VMC conditions is a choice of the pilot (i.e. a state of mind) with very little observable difference. In most cases a sensible VFR plan will also be IFR legal and compliance with the IFRs will also satisfy the VFRs (subject to being in VMC conditions). One of the few times this isn't true is when you are flying over terrain higher than 2000 ft AMSL and want to be less than 1000 feet above it - which probably isn't that sensible to begin with. This case also gives the 'odd feature' of having an altitude band which is not IFR legal but above and below that altitude are legal.
Because the IFRs and VFRs become effectively the same for most PPL/VMC operations in class G, it is simply the choice the pilot has made in his mind (a state of mind) that determines which rule set he is following.
Last edited by mm_flynn; 20th Mar 2007 at 20:39.
