pilotrobbie wrote:
I guess people have opinions, but I think some comments are bit too far here and a little unnecessary
Which ones?
Snoopy wrote:
Isn’t that a legal requirement for ifr?
No. But you have to have another gyro instrument with a separate power source. Traditionally the AI is vacuum powered while the turn indicator/coordinator is electrically powered.
If you have two AIs, the second one should be an electric (or vacum) then?
Ibra wrote:
If you have two AIs, the second one should be an electric (or vacum) then?
Preferably powered from a different source than the primary, yes.
Good luck surviving a flight in IMC down to minimums with only a functioning turn coordinator… that’s Russian roulette unless you practice no gyro PAR approaches for hours and hours and hours..
You might be surprised that nearly all of my FAA IR training, and certainly all of my FAA IR checkride, was partial panel i.e. AI covered up, with the TC and the DI being the only gyro instruments 
Every approach down to minima and only then you look up.
Now imagine the VOR runway 04 approach at KCHD, with a VOR inbound and VOR crosscuts (two different VORs!) and only one VOR receiver which has to be continually retuned, while you are flying a heading and altitude, or heading and vertical speed / stepdown fixes. Pure 24ct masochism.
But with 2 flights a day I was damn good, as anyone would be – at the end of the two weeks and for not much longer after that 
I stayed on UK time (in Arizona) so up at 3am, first flight 8am, then a sleep for an hour, second flight 2pm.
It isn’t particularly hard to fly on the TC so long as nothing else goes wrong and you don’t have to do complicated things at the same time.
The DG would have to be an electric driven slaved compass HSI to qualify as a limited panel, and they usually are with US schools. EASA limited panel exercises (timed turns, climbs, descents, unusual attitude recovery) are based on a T/C and a compass. The FAA requires a limited panel 2D NPA approach, but usually with a functioning HSI so there is an element of apples and oranges in the comparison.
In EASA land the limited panel sign off is carried out in the SIM, the IR loss of glass exercises carried out with a standby EHSI and DG.
For true masochism the Canadian IR in the 1970’s might include a limited panel (using a compass and T&B in a wheezy Apache) LF four course range approach – at least not OEI/asymmetric.
RobertL18C wrote:
In EASA land the limited panel sign off is carried out in the SIM, the IR loss of glass exercises carried out with a standby EHSI and DG.
In my 61.58, I had ILS on standby AI and HSI in O2 mask and smoke goggles.
How you would adjust the approach minima if you have no AI on partial panel, I doubt one will be comfortable going down to 200ft?
Of course it should not matter what are you using for IF, if approach needles are dead in the centre but the tolerances are not the same between full and partial panel…
Ibra wrote:
How you would adjust the approach minima if you have no AI on partial panel, I doubt one will be comfortable going down to 200ft?
What is safer? Continue if stable on the needles or go around partial panel??
