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VFR Wake turbulence separation in Class E airspace

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VFR Wake turbulence separation in Class E airspace

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Old 24th Nov 2005, 20:48
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Ohcirrej
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VFR Wake turbulence separation in Class E airspace

Right my little pretties, who wants to play this question?

Mr Jerricho now works 2 terminal areas (Saskatoon and Thunder Bay) which are Class E airspace out to 35 miles, for simplicity sake 3500 feet to FL230. Each tower has a Class D zone 4 and 5 miles respectively up to 5000 feet.

Now, the game is that our little Manual of Operations (ManOps, the Canadian equivalent of MATS Part 1) states that thou shalt apply wake turbulence separation between known traffic......simple. No differentation regarding VFR or IFR.

Thunder Bay's airspace has 2 areas where the local VFR trainers go out and play. When they depart YQT, we receive a flight progress strip (it's electronic known as a FDE (flight data entry) and the VFRs call us on our terminal frequency, tell us they are stooging out to their practice areas and will be operating normally 4000 or 6000 feet and down. The aircraft are never identified on radar

One of the "training areas" (I am using the term loosely, as it is E airspace) is adjacent to a left downwind/base for Rwy 07. As far as I am concerned, these trainers are known traffic, thus according to our ManOps, wake turbulence separation should be applied. Aircraft involved are both on the Terminal frequency. Doesn't this kinda go against the whole concept of Class E?

Any other E airspace controllers out there have anything similar or thoughts?

I fricken hate Class E airspace.
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Old 25th Nov 2005, 02:44
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Hi Jericho,

Some questions that spring to mind:

How does WT have to be applied in Knuckaland? In Oz it's when the lighter aircraft will be operating within 0.5NM either side, less that 1000FT below and (insert relevant distance/time)NM/minutes behind. Assuming something similar there, can the 'training area' be 'moved' (as much as you can move a training area in class E for VFR)?

Can you use radar to help determine the lateral separation mentioned above? Sorry, just reread the original post stating the VFR guys are never identified.

Are the TWRs situated such that you could potentially separate these aircraft in azimuth?

Can you limit the airport traffic to within X DME or inside X visual fix and limit the VFR guys outside of Y visual fix which, allowing for nav tolerances, facilitates separation?

I know the VFR guys aren't subject to a clearance, however, can they be instructed to operate not below a level and the heavier airport traffic not above a relevant separated level?

Definately advantages and disadvantages to E class airspace.
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Old 25th Nov 2005, 03:31
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Here is Oiltown and also down in Cowtown, admittedly Class C for both, we tend to apply wake turbulence separation against unknown traffic too. Usually, that involves descending mediums and heavies to 5500 instead of 5000 where the base is 4600. Makes sense to me really, since a little fella can still be knocked out of the sky whether you know who he is or not!
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Old 25th Nov 2005, 06:11
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In Oz, traffic (i.e VFR in E or G) is only known when flight details are known, basic details is enough, and the a/c is in direct comms with ATS. Just closed frequency ends the relationship, as the 'details' could change immediately.

So not in direct comms makes it 'unknown' even if radar observed.
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Old 25th Nov 2005, 07:17
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<<I fricken hate Class E airspace.>>

Then you should have stayed in Class A my son!
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Old 25th Nov 2005, 17:08
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Ah, HD, but it's so character building and makes you think of stuff you'd never have had the pleasure of if he'd stuck to boring safe Class A.

As to the original question, I don't see how you can comply with the instruction in ManOps. You can't tell VFR traffic what to do so how can you apply wake turbulence separation?

Can you ask whoever writes ManOps? Back here in the UK you could at least ask the editor of MATS Part 1 about such things and, (unlike some of the Inspectors), in my experience you'd get an answer.


Edited for grammer.

Last edited by Spitoon; 25th Nov 2005 at 20:13.
 
Old 25th Nov 2005, 19:36
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Why would you apply any kind of seperation between VFR and IFR in class E???

And yes, I'm glad we shed the tiny bit of Class-E my unit worked 2 years ago.
(It was removed when a neighbouring TMA expanded)

Class E is a can of worms.
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Old 25th Nov 2005, 20:05
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but it's so character building
Yer not wrong mate.

It is a whole can of worms isn't it? Thanks for the thoughts so far, and please, if there are any others out there with a well built character ( ) who plays with Class E, please please please share your thoughts.

Me, I think it's a crock, but that one little word "known" in our manual makes the dung heap smell that little bit more. Especially if something stupid did happen and an investigator threw the book in front of you and said "Look, it was known traffic. Why didn't you do something?"
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Old 25th Nov 2005, 20:44
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Surely you just tell the VFR guy "caution vortex wake; recommended spacing is..." and leave him to it?

Or after the wine I've just finished am I missing something?

From the pilot side, VFR means I do the lookout & separation and if I see something that looks bigger than me I give it an even wider berth.

You should try class G sometime - what larks then, Mr Pip! What larks!

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Old 25th Nov 2005, 21:15
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Might seem an odd question but have you tried asking some of the local controllers who have been using that airspace and rule book for years? Do they think it unusual as well?

From a pilot's point of view, if operating VFR in class E, we would expect that responsibility for wake avoidance would rest with the pilots i.e. see and avoid (both the aircraft and it's wake).

TP14371 does not say that ATC will provide wake separation in such cases.

Regards,

DFC
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Old 25th Nov 2005, 23:20
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Ohcirrej
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Thanks YVR.

That's exactly the point I'm getting at.

As to your suggestion DFC (and it's bloody good one), this little topic of "known" came up and had people scratching their collective heads going "Uh-oh".

Aluminium - thanks so far mate, but I'm talking beyond spacing on final approach.
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Old 26th Nov 2005, 02:36
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The way I read it you are expected to apply (somehow) Wake Turbulence separation to an aircraft not subject to a clearance - at random levels and manouvres - not radar identified, in a Class of Airspace where by ICAO definition, VFR is not separated from IFR?

I have only one word - impossible.

Actually I have a second - stupid.
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Old 26th Nov 2005, 07:37
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Uncommon Sense,

Agree entirely, no separation required at all !!

Got to be one of the most ridiculous requirements Ive heard in a while
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Old 26th Nov 2005, 19:42
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From the CARS:

4) Where air traffic control services are provided to aircraft operating in Class E airspace, the services shall include separation between IFR aircraft.

Don't see anything in there about VFR and wake turbulence.

If you look at MANOPS you will see that you apply wake turbulence to known aircraft to which you are providing 'Radar Control Service'. Radar control service means vectors if you read the definitions. So unless the VFR aircraft is a departure all they are entitled to is a cautionary. Towers - even those with radar - sure don't apply wake turbulence separation even in Class C, except to departures. Why would a terminal unit do it?

From Manops

B. RADAR CONTROL SERVICE — The
control of aircraft through the provision of
radar vectors in order to establish required
separation and/or desired spacing between
aircraft and between aircraft and
obstructions.

533.1
Except as specified in 384, apply the
appropriate wake turbulence radar minimum
between any aircraft you provide radar control
service to and any known aircraft.

381.1
Except as stipulated in 384, apply the
appropriate wake turbulence separation
minimum to: (N)(R)

A. any category aircraft that takes off into the
wake of a known heavy aircraft; and when
specified

B. a light aircraft that takes off into the wake of
a known medium aircraft.
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Old 26th Nov 2005, 19:47
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Ohcirrej
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Ah Swish, nice one mate

You got time to pop in to Winnipeg and tell our butt-head managers this stuff?
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Old 26th Nov 2005, 21:00
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What are the mosquitos like at this time of year?

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Old 27th Nov 2005, 02:04
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Jerricho,

One of the "training areas" (I am using the term loosely, as it is E airspace) is adjacent to a left downwind/base for Rwy 07. As far as I am concerned, these trainers are known traffic, thus according to our ManOps, wake turbulence separation should be applied. Aircraft involved are both on the Terminal frequency. Doesn't this kinda go against the whole concept of Class E?
1-Are we 'confusing/mixing' Known Traffic with Radar Identified Traffic?
I say if concerned traffic is identified, you can apply the appropriate NM WTC seperation on the radar. And from this...

2-Can we not apply the KISS principle there and seperate the 'Training Area' which has known traffic in it from other Radar identified traffic to cover for WTC (not sure how practical this is in your case since your 'Training area' seems to be close to your circuit).

Finaly, is this one of those debates where "Who cares, textbook says..." vs "I am morally responsible regradless what paper and ink says"?

In anycase, whenever classes of Airspace other than A start to mix, it becomes black magic voodoo if you ask me.
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Old 27th Nov 2005, 02:20
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Ohcirrej
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Smurf, the VFRs are never radar identified. They depart, tower ships them over to the terminal frequency and they stooge off on their merry way. They are deemed "known traffic" because old mate comes onto the frequency and say "Hey there, we're going to head out to the Hazlewood area and operate 6000 feet and down". Thing is, these "training areas" aren't actually defined as advisory areas (I think once upon a time they were, but that changed), and as I said, the aircraft are on the terminal frequency. They also have a tendency to wander around a bit.............

You're right though, class A is so much easier.
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Old 27th Nov 2005, 05:27
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Jerr, I see where you're coming from, and my KISS idea comes from a place where they had a defined 'practice area' around a VOR (it was in the DAH since it was a small E chunk in a D and displayed in the CFS, but not a CYA so go figure (yeah I am first to admit ignorance on airspace design)). Also the Tower shipped us Identified targets.

Now if this is becoming problematic over where you work maybe they need to do something similar. Anyway if it was working for this long why change it, right?
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Old 27th Nov 2005, 08:37
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The problem that arises is that aircrew that fly in the area that's getting the extra service get to expect that service all the time in Class E. When they don't get it and something goes wrong you're gonna pay. For example a lot of terminal units will automatically apply conflict resolution and wake turbulence even though its supposed to be on request in Class C. The aircraft descends 500 feet, is still in Class C but talking to a tower, and they don't get that level of service.

We went through this with a tower that was issuing instructions outside its control zone. Long story short, the control zone was made bigger but not before Transport chewed some butts over exceeding their authority.

If you need more ammo...

128.11
Issue a cautionary to any aircraft if:
A. you are in communication with the aircraft;
and
B. 1. you observe on radar that an aircraft will
have less than the appropriate radar
separation minimum from a preceding
aircraft; (N)

The note says:

128.11 B. 1. Note:
This applies to an aircraft other than one to which
you are providing radar control service.


and... radar control service is vectors. So unless you vector the VFR it's a cautionary. Period.
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