In landing though, I don't know about you, but I wouldn't touch my trim wheel. smile

@Greybeard: for take off, i only rudder trim mostly. At start up check wich direction prop is turning over cowling: left to right--->trim rudder right. right to left---->trim rudder left. Trim pitch neutral, then, if after a few take offs you see that this particular aircraft needs much pushing on the stick while leaving ground , trim pitch slightly for dive. If it needs much pulling, trim slightly for climb.

Yowza, guys.
I neutralize trim as much as I can on a landing, as in real life.
Grey, my guess is you're coming in too steep, which is typical for most sim pilots. Most sim pilots want to see the entire run way out their cockpit, when really, you need to approach longer and more shallow. Fly the aircraft TO the runway.

Try the notion of flying the aircraft TO the ground, instead of floating the aircraft onto the ground.

Trim doesn't change how far the elevator can go, just the force needed by the pilot to maintain a given control position for a given aircraft condition (weight, airspeed, altitude, etc.). Folks going from nimble/light aircraft, like the Cessna 152, often have problems with the additional oomph needed to flare in a heavier aircraft like the C172 or C182 on their first few flights. Trimming does help reduce the force required to flare, but it doesn't magically extend the elevator. It's possible that whoever was having problems with landing that Cessna was trimmed for level flight (more nose down), not descent (more nose up), which is a big difference. Had they been trimmed properly, even with a forward CG, they would have had no problem controlling the aircraft through touchdown.

Setting the trim to full nose up causes problems not only for the pilot who flies afterwards and doesn't check their trim wheel (see Fishingnut's great learning story above) but could also be a significant problem for the landing pilot: trying to execute a go around by pushing in the power will cause the aircraft to pitch up sharply, losing airspeed and causing the pilot to fight the controls to prevent a stall. In fact, I'd go so far as to say that setting the trim full in any direction is always a bad idea - the trim should be set to just what is needed, no more, no less. If a pilot needs full trim one direction or the other to maintain control of the aircraft, they're probably in more trouble than they realize.

In real life, I was taught to trim often and I found it really helped the stability and smoothness of my flying. I learned to trim whenever I felt any force on the yoke, including simply maneuvers like level turns (tilt the yoke with one hand to begin the turn, spin the trim wheel down a couple times with the other to maintain altitude, reverse the process for leveling out). Trim, trim, trim, trim, trim, trim, trim... Took a lot of the work out of my arms and put it into the trim tabs, which never complained about the extra duty.

There are pilot preferences on whether or not to trim a force against the stick or to trim forces out (aka neutral trim). My preference is to trim neutral (i.e., no input force needed to maintain descent attitude) and have used this approach in real life on Cessna 152s, 172s, 140s, Piper cubs (J-3), PA-12 Super Cruisers, and a Stinson 108 and also have not spent any time in a hospital.