I get a QNH from French & German info services all the time on first contact (VFR), just after I’ve told them my current FL, which is usually very obviously above transition level. I used to repeat my flight level, thinking they missed it, but now I just read back the QNH and don’t sweat the small stuff.
Many pilots in aircraft with two altimeters set the second to QNH for terrain clearance and only set the primary to 1013. This is especially useful when flying IFR, where the primary is typically set to 1013 as soon as cleared to a FL, which can happen very low.
So some like to have the QNH available at any altitude.
I recently had an amusing instance where Brize Radar refused to believe I was at FL095. When he eventually ‘found’ me descending through 6,000 feet it sounded like he fell out of his chair 
It’s way more fun when it’s QNH = STD day
Capitaine wrote:
I recently had an amusing instance where Brize Radar refused to believe I was at FL095
Did he had Delta airspace NOTAMed active?
It was the temporary restricted area around the RAF Fairford airshow last month. The Hurricane at 500ft got a better service :/
OCAS, you can do anything you like, so the TA is irrelevant. Just make sure you set 1013 or a right QNH to avoid busting CAS. This is true everywhere I have been.
In CAS, ATC tell you what to do.
In 20 years in Europe I have never had to know the local TA.
Must be doing something terribly wrong
Peter wrote:
OCAS, you can do anything you like
In many areas OCAS is associated with reporting obligations, including altitude reporting obligations. So while you can fly whatever track or level you want (subject to general rules like the semicircular rule) it is not at all certain that you can use whatever altimeter setting you like.
subject to general rules like the semicircular rule
That one is rarely cared about – by anybody. Some ATC in France did care about it, on one flight I did years ago.
is not at all certain that you can use whatever altimeter setting you like
Why not? So long as you remain OCAS. Obviously flying on QNH while avoiding FL-specced CAS base is dumb (even though one of these questions has exactly that as the correct answer )
It is a good idea to have a reasonable QNH set so you can fly at funny levels e.g. 3700ft – to minimise chances of a mid-air.
Peter wrote:
Why not?
Because – as I wrote – you may have a level reporting obligation in OCAS. If you do, then obviously you must report your level using the proper altimeter setting.
gallois wrote:
AiUI Italy is the only one which deviates from the rule by being East/West rather than North/South
You mean the other way around. The default is to have different levels for “generally eastbound” (0-179) and “generally westbound” (180-359).
