Together we make EasyVFR

Notifications
Clear all

Circuit height on Ev4 plates

18 Posts
4 Users
2 Likes
1,345 Views
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

Circuit height as currently shown I feel could be misleading and is, I believe, wrong.

Circuit height should be either shown at what it actually is i.e. 1000ft, 800ft or whatever or alternatively it needs to be qualified to what is actually being shown i.e. airfield elevation + circuit height( QNH). A lot of pilots, at least in the UK fly as I do on QFE when in the circuit and showing as it currently is has the potential for confusion.

All the guides I know of, (Pooleys,AFE etc) just show the circuit height and then the individual pilot decides himself whichever he wishes to fly it either QNH (+ airfeld elevation)or QFE ( actual height above the threshold)

Either way some sort of clarification is needed on the plate.

17 Replies
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

bump

Reply
Heiko Fricke
Posts: 33
Beta tester
Eminent Member
Joined: 5 years ago

Alan,

please check the attached German DFS plate as an example.

It shows EDRY elev on the top (312 ft), circuit height is 1200 MSL (hence 900 AGL).
Please also note that there are 2 other fields very close to us of which you see their traffic circuits partially in the top right corner.

I don't know if this is the best way of describing where you should be in the air but I agree there definitely is the need for a standard

 

Rgds

 

Heiko

circuit heights

.

Reply
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

Hi Heiko,

Yes there needs to be a standard and if you have a published airfield plate then as you say it is normally shown.

However I was actually referring to the Ev4 small airfield layout plates, not published plates. The circuit height is currently being shown as airfield elevation + 1000ft which could be misleading to some.

See attached...Sorry I don't know how to add a screenshot directly.

Alan.

Reply
Posts: 995
Admin
Noble Member
Joined: 5 years ago

I see Alan’s point. I never learned flying using QFE, so I never realised the possible confusion.  Whenever an altitude in EV is shown without amsl/agl/fl postfix, it is also to be read as amsl. So that can be considered EV’s standard 😉

But I see when used to flying QFE, the circuit alts in AMSL are a pain. Maybe we should do like the French, they display circuit altitudes in AMSL, but the altitude in AGL is displayed between (). So 

1200(700) would mean 1200ft amsl, 700ft agl. What do you think?

 

Reply
6 Replies
Heiko Fricke
Beta tester
Joined: 5 years ago

Eminent Member
Posts: 33

Rob,

I like your French proposal best. That's pragmatic.

But let's please stick to feet. As long as there are not too any Russians around we can skip the meters ...

Best regards

Heiko

Reply
Joined: 5 years ago

Trusted Member
Posts: 60

So 1200(700) would mean 1200ft amsl, 700ft agl.  -  I like this idea a lot as a general principle.

 

Reply
Beta tester
Joined: 5 years ago

Reputable Member
Posts: 236

Hi Russ. Yes I was sort of hoping that this would have been amended in.575 but I see it is still the same and could be very confusing for those who aren't flying in the 'Flatlands'.

My own airfield currently has a suggested circuit height of 1990 ft with no qualification of what this is supposed to be.

Also if you look at some, not all, and I am unsure what makes some different(?), the Ev4 plates have 'direction arrows' on the plates with unqualified QNH circuit heights.

I would like to see this given some urgent attention please Rob!

Regards,

Alan.

Reply
Admin
Joined: 5 years ago

Noble Member
Posts: 995

The amsl(agl) inplementation is on the todo list, and won’t be long before its implemented. But why the urgency? If for an altitude nothing is specified then its always AMSL. “Unqualified qnh circuits heights” I don’t know what that exactly means, but its simply airfield elevation+circuitheight AGL. All circuit altitudes are in AMSL for all airfields in entire europe where they are given for, not much to misinterpet ;-)?

Reply
Beta tester
Joined: 5 years ago

Reputable Member
Posts: 236

'All circuit altitudes are in AMSL for all airfields in entire europe'

Sorry Rob but that may apply in Europe but certainly not the UK. What is usually shown on a UK 'Airfield Plate' is the airfield elevation in amsl. The circuit height is rarely shown on a UK plate , except in Pooleys, AFE, etc. then it is it is shown in agl.

Alan.

 

Reply
Joined: 5 years ago

Trusted Member
Posts: 60

It's always been this way in EasyVFR - 4 is the same as 3 was. It's pretty obvious it's QNH especially if you don't fly in the flatlands but like you having been brought up on it I like to fly the circuit on QFE and land at zero, having both will be great as will give the correction to QNH at a glance when approaching fields with no tower. However I'm entirely unconvinced it needs to be written out 8 times for an Airfield like Sywell with 4 runways and with the longer notation the chart is going to be seriously cluttered - Rob can we consider just having it once ? I don't believe I've ever seen an airfield with different circuit heights for different runways. (Although just to complicate things there is often a different height for helis and microlights! )

 

Reply
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

All UK guides ( Pooleys, AFE etc) normally show circuit height to be flown at AGL, QFE. ( Height above threshold.

Having said that I suppose it doesn't really matter as long as after the circuit height in Ev4 it states what it is you are actually saying. Just state if it QNH or QFE after it is all that is needed was my point to avoid any confusion.

Personally I think the circuit height should always be shown at what is ...AGL

Alan.

Reply
Posts: 995
Admin
Noble Member
Joined: 5 years ago

Keep remembering, the ancient pocketfms desktop, ev3 and ev4 always assume AMSL when no reference is given for an altitude. We’ll implement that French system, I think its obvious the lowest value is AGL so something like 1700(1000) says it all I think? No need to do 1700amsl(1000agl) I think?

but just purely for my own interest: how do you know QFE for an airfield? I’ve never learned to use QFE, always AMSL simply because the QNH is always obtainable from a regional FIS (or LARS in the UK?) so approaching an uncontrolled airfield and entering the circuit at the correct altitude is pretty obvious this way. But how do you know what to set the altimeter setting to to land at exactly 0ft (that is what qfe is isn’t it?) when approaching an uncontrolled airfield? Even when controlled, AFIK you always get QNH reported, I don’t recall ever having heard a QFE. Again, just trying to learn something here 🙂

 

Reply
1 Reply
Joined: 5 years ago

Trusted Member
Posts: 60

On approaching a field with a radio service you’ll always get a QFE - approaching an unmanned field you simply wind off the appropriate height from the QNH to arrive at the QFE. It’s always accurate to within 40 or 50 feet which is more than accurate enough for VFR. Agree about the brackets not needing additional notation. Did you see my comment above re fields with multiple runways?

Reply
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

There are quite a few airfields that are now not using QFE unless you specifically ask for it. Redhill only use QNH unless you ask for it. Sherburn in Elmet only use QNH. Perth only uses QNH. So it can be a confusing picture. Yes agreed you can sort it out on arrival/departure by knob twiddling the altimeter either way but it has the potential for confusion if it is not stated on the plate exactly what is being shown.

The easiest way is to just show on the plate the airfield height in feet amsl and the circuit height in feet agl.

I agree about dispensing completely with the bent arrows showing circuit heights/direction on the runway approach plates which could cause confusion at Sywell, Gloucester, Haverfordwest, Wolverhampton,Perth etc and many more who have multiple runways.

 

Reply
1 Reply
Joined: 5 years ago

Trusted Member
Posts: 60

Just for clarification it was only the multiple repetition of the height information that I was suggesting wasn't required - I think the bent arrows to the runways are a good idea and should stay .. just that the text if increased to include QNH(QFE) would clutter up the area too much and didn't need repetition 8 times in a small area. 

 

Reply
Posts: 236
Beta tester
Topic starter
Reputable Member
Joined: 5 years ago

The bent arrows though are currently denoting a circuit direction which at some airfields can change as required daily.

No arrows at all would be my view.

Reply
1 Reply
Joined: 5 years ago

Trusted Member
Posts: 60

In EV3 you can turn on or off the circuit info - I'd expect that functionality will eventually repeat into EV4 so if you don't want the arrows you don't have to have them.

Reply
My cart
Your cart is empty.

Looks like you haven't made a choice yet.