Survey Flights operating in the Transition Layer?

[Tikehau63]

This is regarding the portion of flight during the actual flight SVY area and not transit to and from the SVY area.

Am I able to conduct a survey within the Transition Layer (i.e. FL107) in CTA or otherwise?

AIP states that and aircraft shall not 'Cruise' within the Transition Layer - however during the SVY the aircraft is not configured for 'cruising' - it's operating on reduced power, reduced speed and often not 100% clean - therefore it's technically not cruising is it?

[601]

If we had to operate at a true altitude, we would request a block i.e. A090 to FL110.

[Tikehau63]

I forgot to mention the survey area is entirely in Class E airspace - so block levels can't be used.

[mcgrath50]

AIP states that and aircraft shall not 'Cruise' within the Transition Layer - however during the SVY the aircraft is not configured for 'cruising' - it's operating on reduced power, reduced speed and often not 100% clean - therefore it's technically not cruising is it?

I think your logic of why you can do it is faulty but sure you can do it. For me it's airwork. When you submit your details for the survey area to ATC give them a buzz and ask if they'd rather a block or specific altitude request.

[Tikehau63]

I did this but they just wouldn't entertain the idea and I was quoted AIP that 'I can't cruise in the transition layer' - regardless of commercial SVY (or AWK) status.

[Ixixly]

Better yet, just call up ATC on the phone and ask them, if they say they're happy to give you clearance then it's all good! You could be worried about this one little rule but find they have other reasons they won't give you clearance anyway!

[KRUSTY 34]

I heard your exchange with ATC the other day. Thought it was a strange request.

Curiosity now satisfied.

[ollie_a]

Would VFR-on-top meet your requirements or do you need to be receiving a separation service?

[601]

Having only done survey work before the alphabet airspace was thought off, things may now be different. But ATC are there to "control," not dictate.

If you hare having no joy with Airservices, I would approach CASA explain what you require and see what happens.

[andrewr]

"Cruise" probably means anything other than climb or descend through the transition layer.

I expect the problem (and the reason the transition layer is defined) is your altimeter setting. What setting do you use on your altimeter to stay within your upper and lower bounds e.g. if you request a A090 to FL110 block level?

What setting do you report to ATC if they ask you to confirm your altitude? Can ATC be sure of your altitude on their displays relative to someone cruising at e.g. A095 or FL110?

Depending on QNH, there might be an altitude where you switch back and forth between FL and A altitude on the ATC display.

[601]

there might be an altitude where you switch back and forth between FL and A altitude

It can also be the case where you are doing survey at a true altitude. A block level is the only solution in this case.

[Band a Lot]

Request in written form your flight requirements from ATC in advance.

Ask them if they have a preference that a refusal should be directed (Labor, Liberal, Green in Melb) if refused.


I am no expert but ATC must accommodate aviation requirements, not make them

[topdrop]

I don't know of any controllers that would ping you for doing a survey in the transition layer - though I am sure it happens.
I suggest your company puts a Ops manual amendment into CASA for approval subject to whatever conditions - then just quote CASA approval to querying controller - that should shut them up.