Sorry about delay in responding, but all this talk about PA28s made me wonder whether I am the only one who frequently found myself on the wrong side of the drag curve with a PA28-140 when in the cruise??
I used to find in my early days with a PA28 (with the old window winder trim in the roof) that I'd trim for the cruise and find that over a period of time, there'd be a slight tendency to sink, so woud apply a little bit of 'up trim'. Maybe 5-10 mins later, it would still be sinking a little, so I'd repeat the trim adjustment. After just 2 or 3 of these, I'd then increase the throttle a tad - before I knew it, I'd be on the back end of the drag curve. In VMC, that's recoverable - in IMC, could be another statistic.
I know the purists will say that I was going the wrong way about doing this and should have gone through a full 'PAT' each time, but when it's just fine tuning the trim, I would normally (having started in a Cessna 172/150) just tend to balance the column forces using the trim.
I attribute the onset of this experience to having been encouraged by the CFI of the club I was a member of to keep the revs in the cruise to 2250 for fuel economy (as opposed to the normal 2350). This tended to lead to a slightly higher than normal A of A in the cruise, which then exacerbated the trim problem.
If I'm just a cr@p pilot, then I'd prefer it if you just kept it to PMs!!!
