Overhead Zone Transit

[Okavango]

Hi. Passed my PPL a few months back and just starting to put in some hours and planning some adventurous XC's. Planning out routes and it's just bizarrely struck me what to do when transiting an airfield overhead. In training I'd always talked to any airfield I passed though this became part of standard procedure for the local area I was used to. I remember my instructor saying you don't have to talk to anyone if you don't want (he wasn't advocating it - merely stating it). How do you handle zone transits in general - do you always make contact?

[eharding]

Originally Posted by Okavango

Hi. Passed my PPL a few months back and just starting to put in some hours and planning some adventurous XC's. Planning out routes and it's just bizarrely struck me what to do when transiting an airfield overhead. In training I'd always talked to any airfield I passed though this became part of standard procedure for the local area I was used to. I remember my instructor saying you don't have to talk to anyone if you don't want (he wasn't advocating it - merely stating it). How do you handle zone transits in general - do you always make contact?

Well, at the very least it would just be common courtesy, and at best save you from coming face to face with something exciting happening in the overhead which was NOTAM'd, but you didn't actually get round to reading them...or you printed them out, but the cat ate them...or left them on the bus...that sort of thing.

Conington last weekend springs to mind. Fantastic support from the airfield for the aerobatics, but there is not a lot the people in the tower can do if someone decides to blithely sail through the overhead (and the competition box) in a particularly fat, dumb and happy state without bothering to call on the airfield frequency. Twice.

[ShyTorque]

Yes, I suggest you make radio contact in good time, making sure to include your altitude and pressure setting. It's a choke point. Even if you're above the ATZ.

You'll be busy looking out but will probably be concentrating to confirm your position. Someone coming in for an overhead join (might be a non-radio aircraft) might be concentrating on sorting out their circuit pattern and planning the descent onto the deadside.....you might well be in the same piece of air. Get my drift?

[DX Wombat]

Conington last weekend springs to mind

Was that you who had that nasty encounter of the Grob kind eharding?
I believe the pillit of the Grob was given a comprehensive ear-bashing by ATC Serves him or her right. Remember:
NOTAMS APPLY TO US ALL, NOT JUST THE CHOSEN FEW.

[eharding]

Originally Posted by DX Wombat

Was that you who had that nasty encounter of the Grob kind eharding?

No, 'twas Lucky Luke flying when that one went through - I was busy with my Hobbit's second lunch by that stage.

[DX Wombat]

After some of the incidents I have seen with aircraft other than the competitors pratting around in and through the box, I think all of you competitors should have your aircraft fitted with some sort of paint spray gun capable of giving a good coating of something in a nice lurid shade to any box infringers. Imagine the fun they would have trying to explain the nice new paint scheme to the CFI or CO.

[Okavango]

Thanks all. So say for instance I was receiving a LARS service, I'd just leave that frequency temporarily to talk to the airfield concerned then change back after transit?

[BackPacker]

Someone coming in for an overhead join (might be a non-radio aircraft) might be concentrating on sorting out their circuit pattern and planning the descent onto the deadside....

I would hope that somebody on an overhead join would actually be in the ATZ, while people on an overhead transit would be above. Or, at least, somebody transiting overhead would not do so at the overhead join altitude.

As far as I'm concerned, biggest danger would be people doing airwork (aerobatics) in the overhead, or other people using the airfield as an en-route waypoint.

After some of the incidents I have seen with aircraft other than the competitors pratting around in and through the box, I think all of you competitors should have your aircraft fitted with some sort of paint spray gun capable of giving a good coating of something in a nice lurid shade to any box infringers. Imagine the fun they would have trying to explain the nice new paint scheme to the CFI or CO.

Actually, a lot of aerobatic aircraft are fitted with smoke systems, but are not allowed to use them during the competition. But a few bursts of smoke every now and then would be visible for miles around and would serve as a reminder to the blissfully ignorant that something might be going on.

Whether that would be reason to stay away, or to go and investigate these funny shaped clouds up close and personal I don't know though.

So say for instance I was receiving a LARS service, I'd just leave that frequency temporarily to talk to the airfield concerned then change back after transit?

Yes but do make sure that the LARS provider knows you're going to be leaving for a few minutes.

If you have two COM boxes, you could also listen out on the airfield frequency on COM2, while staying with the LARS provider on COM1. Listening out on two frequencies at once does increase your workload though.

[englishal]

I would....

If talking to a LARS unit and transiting high above - say 4k - then I would remain with the LARS unit.

If NOT talking to anyone, I'd give the airfield a shout...Same as if passing abeam < 10 miles, I'd give them a call.

I'd also have read the Notams and avoid any airfields with notams for stuff in the overhead or any with a parachute symbol

[jamestkirk]

Okavango

Also, some airfields have instrument procedures outside CAS. Someone may be in the hold above the ATZ.

[Crash one]

Thanks all. So say for instance I was receiving a LARS service, I'd just leave that frequency temporarily to talk to the airfield concerned then change back after transit?

Just in case you meant this, don't just "leave the freq" Tell them you are changing freq, no matter for how short a time.
No doubt an ATC person will confirm that in a minute.

[ShyTorque]

Quote:
Someone coming in for an overhead join (might be a non-radio aircraft) might be concentrating on sorting out their circuit pattern and planning the descent onto the deadside....

I would hope that somebody on an overhead join would actually be in the ATZ, while people on an overhead transit would be above. Or, at least, somebody transiting overhead would not do so at the overhead join altitude.

You're missing the point. An aircraft arriving at an airfield for an overhead join has first to enter the ATZ in order to do it. This normally involves a descent at some stage. Unless, of course the transit altitude had been at or below the altitude of the ATZ.

I've seen a number of "close shaves" in the overhead of airfields, all of them caused by pilots not noticing other aircraft in the vicinity and a lack of communication.

Are you therefore suggesting that pilots transitting overhead don't need to call the airfield as long as they are above the ATZ?

[Foxy Loxy]

Please call!!

Having worked at a couple of radar units, I've seen first hand the havoc that results from someone blithely passing by not talking to anyone. That's not great when a 737 is just about to establish on the localiser and I'm watching someone out the window blatting through the final approach at 3 miles.

Traffic on a deconfliction service has to separated from "unknowns" by 5 miles or 3000ft. If a contact appears on the screen as primary only, 5 miles lateral separation must be applied against DS traffic. That's a lot of vectoring and hard work, and I'm not even mentioning what else might be going on - other traffic, potential conflictions, pop-ups, co-ordination etc etc.

I've said it before but I'm going to re-iterate: Just because it's legal (yes, you can overfly an airfield at 2100ft without talking to them) doesn't mean it's safe or sensible.

Before I go, one or two more points.
Box two. Use it! It may just be useful one day
Never assume, check. For example, those nice shiny charts issued every March might not be correct. The ones issued this year don't show the IAP arrows at Newquay. Well, we have IAPs.

[Lister Noble]

Also, some airfields have instrument procedures outside CAS. Someone may be in the hold above the ATZ.

These are indicated on the chart by the instrument flight track with inset chevrons.
Some are out of CAS by several miles.
Do these "control" area go down to ground level all the way?
Lister

[englishal]

Box two. Use it! It may just be useful one day

What if you don't have box 2

Still I go back to my point that if you are talking to a LARS provider, and are high above the ATZ (say 4000) then you're better off remaining with the LARS provider (on a Traffic service that is) than switching to a non radar unit.

[FREDAcheck]

Box two. Use it! It may just be useful one day
What if you don't have box 2

Still I go back to my point that if you are talking to a LARS provider, and are high above the ATZ (say 4000) then you're better off remaining with the LARS provider (on a Traffic service that is) than switching to a non radar unit.

Good point. Anyway, you shouldn't just leave a LARS service, you've got to "sign out", so to speak. So should you:

• sign out to call each and every airfield whose ATZ you are flying near?
• stay with LARS (assuming you aren't actually going inside or very near an ATZ), and rely on LARS (and your pre-checking of NOTAMS) to tell you of stuff to beware of?

I mean: how close do you need to be to an ATZ to call them, rather than staying with LARS?

[west lakes]

In the case that Foxy Loxy is talking about, a radar service is actually provided by the airport in question.
In all of the cases that are causing them concern, the aircraft are not even talking to the radar service.

[tmmorris]

You don't just need box 2, you also need an audio panel which allows you to monitor both boxes while speaking on one. We now have a jolly nice Garmin one (can't remember the number) which allows that and also some nice isolation modes if the passengers do too much talking...

Mind you, monitoring both boxes can cause confusion, especially if you monitor 121.5 on box 2 and forget it's on.

Tim

[AndyS10]

Assuming I am already receiving an information service from a LARS unit or similar, what is the correct terminology to request a brief frequency change to get a traffic update from an airfield I am transiting close to?

“Request frequency change....” sounds like I want to make a permanent change when I actually intend to reappear on frequency in a couple of minutes. What do the ATC’ers or others recommend as a clear statement of my intentions?

[ShyTorque]

It's one situation where there is no formal R/T protocol. Just use plain language.

Say something like:

"C/sign, changing to ABC tower (freq) as I pass over the ATZ, will call you back in two minutes".

On your return to their frequency, say something like: "C/sign, back with you, request Traffic Service".

It often happens, I've never heard ATC have an issue with it.