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The Dead Side
19th Jun 2013, 21:19
I'm going to be flying to Cambridge in a couple of weeks. If the weather is poor, then I'd be ambling for an ILS or another instrument approach. Having never carried out an instrument approach in class G, there are a couple of things which become apparent, such as traffic with no legal obligation to stay out of your way.

Obviously if it's VMC, there will be plenty of traffic about, but then it seems silly not to just join visually.

The thing that I'd like to ask about is the R/T which I should expect on arriving at Cambridge, in such an event which demands an instrument approach. As I understand it, I will call Cambridge APP before arriving and ask for an ILS/VOR/NDB e.t.c, but is the response likely to be a clearance (in class G..?) or just information for the approach/runway?

Thanks in advance.

Gertrude the Wombat
19th Jun 2013, 21:28
If there's a radar controller on (which there usually isn't) you can get vectors to the ILS, otherwise you'll have to fly the whole procedure including the NDB outbound bit[#], in which case you'll have a Procedural Service.

Radio is (AFAIK! - almost all my approaches have been in class G) the same as for controlled airspace.

If ATC happen to notice them they might tell you about a gaggle of microlights flying across your path at 20 knots, but if you'r visual it's your job to see and avoid.

[#] Actually there are three ways of avoiding the NDB outbound bit in addition to vectors:

(1) Direct join as shown on the plates, I've not tried this myself, DME arc.

(2) Cambridge does have a GPS approach. But I found it so easy that it seemed like a waste of expensive instrument time!

(3) Tell ATC you're self-positioning for the ILS in VMC ... intercept it somewhere above Lakenheath, using a method of your choice (eg GPS, or even by looking out of the window if it's actually VMC).

thing
19th Jun 2013, 21:32
Can't say I've really noticed a difference in the R/T. I fly near Doncaster which is CAS and Humberside which isn't and have done IA's at both, plus at my own airfield which is mil and I'd be hard put to think of a difference, other than I can get a PAR at my own place besides the usual ILS, NDB etc.

It might be an idea if you know you're going to do an IA to let them know before hand rather than just pitch up and ask for one, at least they'll know you're coming; I take it you'll be flying IFR on the way.

Edit: If you're doing an IA in VMC then please take a safety pilot or at least a passenger who can spot other a/c.

Another_CFI
19th Jun 2013, 21:34
The same R/T as an airfield inside controlled airspace, unless radar is not available in which case they may indicate that it is a Procedural Service.

Therefore if they wish you to enter the hold it would be something like:-

"G-CD, Procedural Service, Cleared to the CAM at 3,00ft report entering the hold".

If they are vectoring you to the ILS then it would be something like:-

"G-CD, Traffic Service, radar vectors for the ILS runway 23, fly heading xxx".

The Dead Side
19th Jun 2013, 22:09
Thanks for the answers.

The same R/T as an airfield inside controlled airspace, unless radar is not available in which case they may indicate that it is a Procedural Service.

To be honest, it's what I had expected. However I still can't get my head around how (say if radar was available) I could be cleared for an ILS approach/to intercept localizer, in uncontrolled airspace.

thing
19th Jun 2013, 22:45
Don't think you are 'cleared'. I can't regurgitate the patter after a bottle of Claret but I'm sure 'cleared' doesn't enter into it unless you're talking about the 'cleared to land' call.

Gertrude the Wombat
19th Jun 2013, 23:08
However I still can't get my head around how (say if radar was available) I could be cleared for an ILS approach/to intercept localizer, in uncontrolled airspace.
You are cleared for the ILS in that nobody else who is also receiving a Procedural Service from Cambridge Approach/Radar will be guided into the same piece of sky at the same time.

What you don't get is any attempt at separation from anyone else flying around in that bit of class G who is not receiving a Procedural Service from Cambridge Approach/Radar. Although if I'm about to fly through the hold or the approach VFR I do call them up and ask whether this will give them any problems for their IFR traffic.

bookworm
20th Jun 2013, 06:25
To be honest, it's what I had expected. However I still can't get my head around how (say if radar was available) I could be cleared for an ILS approach/to intercept localizer, in uncontrolled airspace.

A clearance is a contract between and aircraft and ATC, which establishes that if the aircraft flies the specified trajectory then separation from some other classes of aircraft is guaranteed. In class A/B/C, the separation is from all aircraft. In class D/E it is from other IFR aircraft. In class F/G it is from other participating aircraft.

If you don't like your clearance in class E, you can always cancel IFR. Similarly, if you don't like your clearance in class F/G, you can always decline to participate, though ATC procedures allow ATC to assume that an aircraft will adhere to its clearance unless it tells ATC otherwise.

Cambridge will, by default, clear an IFR inbound to the CAM. If you want a direct arrival at Cambridge using the 10d arc, you need to negotiate it with Cambridge Approach well in advance. I think that if an aircraft is cleared for a direct arrival approach from a long way away, it seems to more difficult to assure separation from other IFR aircraft than if you're coming in to the CAM at 3000 ft, but I've never discussed that with them. If you're coming from controlled airspace, it can be tricky. I've found that while coordination between Essex and Cambridge is generally good, getting a direct arrival is not always as easy as you might expect. So don't be too surprised if the clearance is to the CAM at 3000 ft or above. Of course if radar is available, it's much easier.

TDS, where have you done most of your IFR flying, and where are you arriving from?

tmmorris
20th Jun 2013, 15:54
Just to add that the main piece of information they will need, if you are expecting a procedural service, will be your ETA at the beacon ('Cambridge Approach, G-ABCD with information November, 3000ft on 1021, estimating the CAM time 21, request a level for the hold.')

They will then probably ask if you want any holds - in case you want them for training - unless they are busy in which case they will issue a level and an expected approach time. If you have a pre-booked slot and you hit it reasonably accurately then you should be fine.

Having never really flown approaches in CAS I guess that feels normal to me!

Tim