Overflying airfields

[Coke611]

What is the normal actions to take if, for example, your route overfly's an airfield? Fly around the airfield? Fly over at significatly higher than the circuit? Also, what about radio calls. For example, if you are on thames radar, and you are overflying an airfield, do you contact the airfield and say something like : 'G-XXXX Requesting permission to overfly the field at 3000ft' or just stay on thames radar?

Cheers,

Louis Coke

[PhilD]

My understanding:

If you want to fly through an ATZ you must contact the airfield and, if ATC, have obtained permission (Rules of the Air - Rule 39).

Assuming you are not in controlled airspace and you stay outside the ATZ (i.e. normally over 2000' AAL) you can do what you like and you don't need to contact anyone or obtain permission to overfly an airfield. However I think common sense dictates that if the airfield is manned you should at least let them know you are there and make your intentions known.

My policy if I am on a radar service and approaching an airfield just above the ATZ (say within 1000') I will request a switch to the airfield frequency to make contact, then go back to the radar once I have finished with them (either because the transit is complete, or if they tell me there is no traffic around).

If the transit is much higher (e.g. 4000' or more AAL) I think you are better on the radar where they can see other traffic anyway. If you are not on a radar service there is no harm in letting the airfield know, but they are not likely to be interested if you are well above the ATZ.

[ChiSau]

Phil D

Do you let the ATSU giving you the radar service know that you are changing frequency to ask for zone transit from an airfield, or do you just flick over and ask them and then flick back again?

And similarly, when given permission to enter the ATZ, do you tell the ATZ ATSU that you're changing back to your radar provider??

And then (!!) - do you swap back again to call overhead the airfield???

And then (!!!) - do you need to tell the airfield when you're leaving their zone????


:confused: :confused: :confused: :confused: :confused: :confused:

[Tee]

As PhilD says, the average ATZ rises to 2000' from the surface.

I'm always surprised by the number of pilots who choose to overfly at 2000' (or thereabouts) on the QNH. If the airfield elevation is, say 600', flying at 2000' on the QNH means that the aircraft is 1400' aal and, in this example, might conflict with aircraft descending on the deadside from a standard overhead join. Using the same example, the aircraft would have to fly at 2600' on the QNH to be flying at the upper limits of the ATZ.

[bookworm]

If you are flying through an ATZ, an ATC unit is unlikely to release you back to a radar unit until you have left the ATZ. Even if there is no ATC, it would seem to make sense to remain on frequency until you are clear.

If you are not passing through the ATZ (i.e. more than 2000 ft aal), you should consider the possibility of IFR traffic. Airports outside controlled airspace with instrument approaches (marked by a chevron on the CAA chart) often have traffic holding above and close to the airport. It's very important to talk to ATC in such circumstances, even if it is not mandatory.

A unit providing a radar service may have some level of coordination with ATC at such airports. If in doubt, ask.

[FlyingForFun]

ChiSau

If you're in contact with a ground station, never change frequency without telling the previous ground station (or asking permission if they're ATC and you're in their airspace).

In this case, you'd tell your radar provider you're changing frequency (e.g. "Request frequency change to Somewhere on 123.45 to transit their airspace, will return to you when clear"). I like to tell them that I'll return to them - often they'll tell me to retain my squawk if they know I'm coming back. Then contact the station at the airfield you're overflying. When you want to change back, tell them "G-ABCD clear of your airpsace, changing to Previous Radar on 112.34". Simple.

If you change frequency without telling your current station you're doing so, even if it's only temporary, you're asking for trouble when they try to contact you and you're not listening!

FFF
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[Who has control?]

Airfields are real magnets for aircraft, (strange as it may seem :) ) So if if are using one as a landmark, you can bet your bottom dollar that some else is doing the same thing.

Calling up the airfield to let them know that you are coming through their overhead is a courtesy, even if you are above their ATZ.
They may not be too interested in your transit, the guy down in the circuit may not be bothered either, but the other traffic you don't know about that is also using the airfield as a landmark would be VERY interested. Your radio call is a way of letting other aircraft know where you are and what you intend to do.

So, don't hesitate to call the ground station.

[big.al]

I agree totally with Who Has Control -

Last Saturday I flew Netherthorpe to Norwich via a turning point directly overhead Fenland Airfield. Although I was at 3000' QNH, strictly speaking above their ATZ, I still contacted Fenland Radio to advise them I was approaching, gave them my altitude/heading and intentions etc, just to warn them of my presence.

Fenland Radio thanked me for the call - I'm sure that regardless of whether or not it is strictly necessary, it is good airmanship - not to mention courteous - to let them know I'm passing.

In doing so it also helped me out a little because another aircraft was also transitting above their ATZ north-south, and Fenland were able to warn me to keep a look out for the other guy.

[NovNov]

Was going over Compton Abbas a few weeks back. Even though they are just Radio and can't give an FIS I'm glad I did ... They had someone lining up to Aero's at the same time I was expecting to get there!!!

:eek:

[RW05]

If you are going to overfly an airfield please make contact first. Even if you intend staying well above the ATZ you may not know what's going on around you, like aerobatics. Where I fly from we have people leaping out of aeroplanes from overhead the field and well above the ATZ. A lot of people end up in a lot of danger if someone barges through unannounced. Ask first and you'll be told whether it's safe or not. If it's not, or you're just not sure (the field's non radio or no-one answers the radio) it's much safer to go round. After all, it's not that far out of your way, is it?

[Genghis the Engineer]

Going back to the original question.

(1) Always be aware of the details from a suitable guide of any airfield that you'll be overflying. It's important that you know what may be going on down there before you get close.

(2) There are several options,

(i) if overhead joins are not permitted fly directly over the airfield at above circuit height,
(ii)if overhead joins are permitted, at-least 1100ft above circuit height;
(iii) fly such that you will be aligned with circuit traffic.
(iv) fly sufficiently high (well above the ATZ or MATZ) that no conflict is likely.

(3) If an airfield has radio (whether it has an ATZ or not), you should talk to it. If entering an ATZ, you obviously need permission. If you are already on another frequency and don't have a second box, then a series of (slightly non-standard, but entirely clear) calls along the following lines would do the job

"Yeovilton Radar, G-CD"
"G-CD Yeovilton, pass your message"
"G-CD will be flying overhead Compton abbas, changing frequency temporarily to Compton Radio"

"Compton Radio, G-ABCD"
"G-ABCD, Compton Radio, pass your message".
"G-ABCD, Courtesy call no service required, will be passing through your overhead at 2100 ft above airfield height at minute 52, have you any traffic to affect".
"G-CD, thanks for the call, normal circuit traffic, we are on runway ** left hand circuit".
"G-CD"

"Yeovilton Radar, G-CD back with you".
"G-CD".


G

[Coke611]

Cheers guys- makes a lot more sense now!

[bookworm]

Some excellent points Genghis but:

if overhead joins are not permitted fly directly over the airfield at above circuit height

I would have thought that if an airfield doesn't permit overhead joins it probably has a reason for not wanting you directly overhead. Parachuting and gliding deadside come to mind.

[Genghis the Engineer]

Not necessarily, some don't because they've no deadside - possibly because they've got a fixed wing circuit one side and rotary the other.

Which emphasies my first point about having as much information before overflying as if you were going to land there. (Well, apart from PPR anyway).

G

[FWA NATCA]

Coke,

In the US if you are flying along on an IFR flight plan, then you don't have to worry about getting permission to fly through various control zones (airspace Class B through D). It is up to the radar facility to contact the tower and point you out and get permission for you to fly through their airspace. It works the same way when flying VFR being worked by a radar facility.

If you are just tooling along on your own then it is strictly up to you to announce yourself, and in my opinion it is a very good idea to do so if you are over flying below 4000 feet, or if the field is known to have crazy people jumping out of airplanes.

I am curious if the procedures are similar in the UK.

Safety is a two way street,

Mike

[FlyingForFun]

Mike,

Can't speak from an IFR point of view, but when flying VFR, the regulations are different, although from a pilot's point of view it's almost identical.

Firstly, there are no Class B or Class C airfield in the UK. (Class B is used for upper airspace, and Class C isn't used.) So whereas, in the US, you'll be provided with ATC seperation near big airports (from all traffic in Class B, and IFR traffic in class C - assuming you're VFR), there is no equivalent in the UK.

Flight through a Class D zone in the US is, in my experience, pretty much identical to flight through a Class D zone in the US. When flying in the US, I was told that VFR pilots don't need a clearance to enter Class D, they only need "two-way radio communication" - and that this is deemed to have been established when ATC read out your call-sign - but that, in practice, ATC won't read your call-sign unless they are happy for you to enter your airpsace. So, in effect, you do need a clearance. In the UK, you need a clearance to enter Class D - none of this messing around with call-signs. I get the impression that a radar service is more common in Class D in the UK than it is in the US, but that doesn't make much difference.

We have a very small number of Class E airports in the UK, but I've never been to one, so I'm not quite sure how they work. I'd imagine that there's no real equivalent in the US. (Is ATCBabe around? Babe, is the airport you work at Class E? I think it is, in which case you can tell us all about them from an ATC point of view!) Note, though, that Class E is used for open airspace in the US, but used for control zones around medium-sized airports in the UK - took me a while to understand that one!

The biggest difference, though, is our Class G airports. Many airports are unlicensed, and they would be exactly equivalent to non-towered US airports. But all licensed airports (I said this on another thread, and was corrected, but it's true in 99% of cases) have a 2-mile or 2.5-mile zone, the ATZ, from surface to 2000' agl, in which flight is regulated. These airports can be controlled, in which case the ATZ is effectively controlled airspace. (I don't think there's such thing as a controlled airport in Class G, or even Class E, in the US.) Most of this thread has been about un-controlled, licensed airfields, where although you don't need permission to enter the ATZ, you do, legally, need to get enough information to operate safely.

So yes, there are some differences between the UK and the US. But, from a pilot's point of view, I'd say the differences are negligable - whatever the rules say, common sense says you should talk to any airport you overfly if they have a radio facility.

Hope that helps.

FFF
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[bookworm]

Good description FFF.

We have a very small number of Class E airports in the UK

I don't think there are any. As you suggest, class E is used for controlled airspace around some medium airports, but the control zone itself (the bit that goes down to the surface at the airport) is always class D. The last class E control zone was the Scottish CTR which disappeared a few years ago.

[englishal]

If you are receiving a radar service wouldn't it be better to pass above the ATZ and remain radar???

Another difference in the US is that once you are receiving a radar service from Tracon or Centre then you are automatically cleared through Class D and Class C (C is equiv to D in the UK) airspace. The controller may hand you off to XYZ tower who will then hand you back to Tracon / Centre...

cheers
ea:D

[G-SPOTs Lost]

Depending on the kit in your airplane you could always try the box 2 call i.e.

Airfield B this is G abcd box 2 working Airfield A looking to route from c -d through the overhead at 3000 ft anything to affect?.

The box 2 call tells the controller you are already receiving a service from somebody else and are just "checking in" if theres nothing to affect continue with Airfield A.

Handy if there is two of you and Airfield a's frequency is busy i.e. you dont have to call to QSY and you dont have to call back with them.

Just a thought not exactly CAP413 I know....

[Romeo Romeo]

There's a comment about this in the latest GASIL (it's available in the Internet from the CAA site http://www.caa.co.uk/publications/publications.asp?action=sercat&id=7 ). It says that A/G frequencies are only designed for use up to 3000ft AAL. If you use them above this then there could be confusion with other aerodromes. Personally, I'd give them a call if I was slightly above this, but it might be best to include the aerodrome name in each call to avoid confusion with nearby aerodromes on the same frequency. I've certainly been confused by an aeroplane at Sywell when I've been approaching Compton Abbas.

[slim_slag]

Mike,

I had something come up recently when receiving VFR radar services from PHX approach, a class B facility with several class D airfields below it.

I was cleared into the class B but at an altitude corresponding to the base of one of the wedding cakes. 100ft or so (no charts on me here) below me was IWA class D, I was heading for FFZ (Class D) which almost touches the IWA class D, and normally when heading for FFZ from that direction I would be at an altitude which would require me to traverse the IWA class D, with appropriate communication with IWA tower.

Clear as mud so far??

When midfield above the IWA class D, PHX approach said something to the effect of 'Flight following cancelled, sqwark VFR, descend at pilots discretion'. So I was in class B, yet the controller had essentially told me I was 'on my own', was sqwarking VFR, had not communicated with the Class D tower below, but approach had essentially told me it was fine to descend at my discretion - this would take me into the class D below if I was to make a sensible descent towards FFZ.

Now FAR 91.129 says


Each person must establish two-way radio communications with the ATC facility (including foreign ATC in the case of foreign airspace designated in the United States) providing air traffic services prior to entering that airspace and thereafter maintain those communications while within that airspace


So as PHX approach is not the controlling agency over the class D, and they had cancelled flight following, and I was VFR anyway, am I going to get asked to make a phone call if I descended into the class D? Should I have stayed in the Class B until clear of the class D below, which would have caused problems with communicating and getting into the FFZ class D.

And from experience I know IWA tower are more than happy to ask (allegedly :)) errant pilots to call them for a pep-talk :eek:

I should know this of course, but don't, and never did call PHX approach to ask them what they would like me to do and where I would stand. As it happened I descended into the very thin gap between B and D and took a non direct route to FFZ, but am still interested to know whether I would have been legal to descend into the D if B and D touched. I think not, but I'm not the ATC procedure expert.

[FlyingForFun]

slim_slag,

In the situation you described (I wish I had my Phoenix charts to hand so I could understand it a bit better, but I think I get it...) I'd ask for clarification. It's always possible the guys at Phoenix made a mistake.

I was once approaching Phoenix from the north, just above one of the class D zones. I requested a VFR transition, reported my position as overhead whichever airport it was that I was overhead, and was given a squawk. I was then immediately told to descend to an altitude which would have taken me into the class D. I'd already instinctively cut the power and started to descend before I realised the problem, asked for clarification, and the controller apologized and told me to maintain current altitude, before telling me to descend a couple of miles later - still well in time to be level at the cleared altitude before entering class B. Even controllers are human!

FFF
--------------------

[david viewing]

Fellow aviators

You might be interested to know that you can view the Phoenix chart (or any other US sectional) at http://mapserver.maptech.com/homepage/
for free.

I don't know how up to date the charts are, though.

[rotorcraig]

Good stuff. Don't suppose UK aero charts are available online in the same way?

[PhilD]

What do you think? Nothing for free here.

[slim_slag]

Thankyou FFF, I called around today, and you would appear to be correct in your assumption. PHX approach are very friendly to us round here, always happy to help and provide excellent service.

I suspect you are talking about Deer Valley, good job you caught yourself before busting their airspace, they also like to pass phone numbers to you over the airwaves :)

Several years ago I had a similar type of experience in that area while flying south from a slap up breakfast in Sedona via the PHX transition. Talking to PHX approach from a good 40 miles out, but the controller did not have radar contact which was confusing him and he was constantly asking me my position and altitude. Turned out I had dialled in the incorrect altimeter setting and I was a little low, good job I caught it or else I would have busted DVT Class D quite nicely. Shows how easy it is to make a simple mistake which can cause a lot of problems.

More recently I was coming back the same way and PHX told me my mode C was reading 41000 ft!!! PHX didn't care, they just told me to say my altitude, made me promise to fix the transponder when I got back, and cleared me into the class B via the VFR transition.

A bit chilly this morning in PHX when flying at 7:30 am, had to wear a jacket in the open cockpit plane! Also had to be aware of the Class B above me when in the climb, that must be the first time in many months year I got over 1000ft per minute out of a 180hp beast with no thermal involvement. At last we are getting cool and smooth air, very nice!

Cheers

[pistongone]

I cant believe that you all seem to have differing ideas as to what the answer to a standard procedure is!!!!
firstly if you are on thames radar then overflying any field in there control area would almost certainly mean entering the london tma!! as it has a base of 2500ft for most of their coverage.Switching one box to another without informing the radar controller could lead to dire consequences!Dont do that!!
and i would have thought the correct trx initially would be "thames radar, request change to stapleford on 122.25" and in my experience the controller would probably have asked if you were intending to call them in plenty of time anyway!as he can see where your present track will lead you in a few minutes time!! What puzzles me though is why you would need to ask this question if you are the holder of a ppl and if you have forgotten in the passage of time,then why not go for a check ride with your instructor and log the hour you need for the once a year rule???
Safe and pleasant flying to all!