The GA planes I fly (with a club) have Garmin G5 PFDs. On these, the horizon/attitude indicator shows a few degrees pitch-up when in level flight. They're adjusted to indicate level on the ground based on the aircrafts' centerline, but in-flight changes in speed or W&B of course shift the actual attitude for level flight. This is kind of annoying when trying to develop instrument skills. The reason for this limitation for certificated aircraft (per Garmin) is an FAA regulation (14 CFR 23.1303(f)):
When an attitude display is installed, the instrument design must not provide any means, accessible to the flightcrew, of adjusting the relative positions of the attitude reference symbol and the horizon line beyond that necessary for parallax correction.
Never mind the "why" of this (it seems odd, but what do I know...). The above text is from a 2017 version of the code. (Actually published in 2011, per the GPO.) When I go looking for current versions on .gov sites, they don't exist. On the current gov eCFR website, I get this response when looking for that section:
The content you requested is no longer in the eCFR. It was removed on 2017-08-30, but the prior content can be viewed here.
There is a similar section of federal regs for transport category aircraft (25.1303) but it has no subpart (f) and says only that a bank and pitch instrument is required.
With all that windup, my question is: does this restriction on attitude indicators still exist? I cannot find a current version of the regs containing this restriction.