I did a thorough preflight inspection and engine run up at U42 using a checklist. I also calculated the weight and balance of the aircraft and the aircraft was within limits but closer to the max than I usually fly. I am also typically flying out of airports at lower elevations.

After completing run up I struggled a little bit to find the taxi ways to runway 34 which the winds were favoring. I tried to find an airport diagram for U42 in advance of the flight but none was available. This struggle had me a bit flustered as this was an unfamiliar airport to me with a more complex taxi system than I am used to.

I approached the runway, checked for traffic, made a radio call and took off. The aircraft struggled more than usual to take off which I attributed to the higher altitude and higher load than I normally carry. However, after takeoff the climb was extremely slow. Normally I climb out at 88 mph (approximately Vy), but I was forced to climb out at about 80 mph (approximately Vx) in order to gain altitude. And the altitude gains were maybe 1/5th the normal rate.

I started to panic and tried to determine what was wrong. Had I grossly miscalculated the load? Was the density altitude far too high than I am used to? Were my flaps mis-configured? Did my plane have the wrong type of fuel? Had the tanks been compromised with rain water that day? Where would I make an emergency landing if my engine was failing?

I remembered my training and focused on "flying the plane." I knew I needed to keep from stalling as this would likely be deadly this close to the ground. I had to keep my airspeed above Vx and fly the plane straight and level without turning. I remembered that trying to turn back to the runway in this situation is often fatal. I had to focus on flying the plane at the expense of navigation or other concerns while determining what was wrong.

My GPS started warning that I was nearing SLC Class B airspace. I believed this was the airspace above me and focused my attention on my airspeed and trying to gain altitude. Suddenly my GPS indicated that I had entered the SLC B airspace. I knew I didn't have permission and I realized what had happened. I was so focused on flying the plane that I hadn't turned left as I had planned and runway 34 was pointed directly at the SLC class B airspace all the way to the ground.

I had gained enough altitude that I was comfortable with a careful turn to the left to get my plane out of the airspace as quickly as possible without stalling the plane.

Once clear of the B airspace, I continued to search my instruments and flight controls for the source of my engine's poor performance. Mixture was good, throttle was full, primer was in and locked. But carb heat was set to hot! I pushed the carb heat control to cold and my engine roared with new life. My airspeed and climb improved instantly and dramatically. I realized what must have happened. During my engine run up I make sure the engine would idle and turned on carb heat to prevent icing. But I had left the carb heat on by mistake and missed the check during the pre-take off checklist.

What contributed to the mistake was the lack of airport diagram for U42 and lack of familiarity with the airport which caused me to become flustered and miss a critical item on the check list. Also, I would have liked to connect with Flight Following from the ground but wasn't sure how to do this at U42. Was I supposed to call clearance? SLC Approach? SLC Center? Had I been on Flight Following a Controller might have warned me I was heading directly for [Class] B or I could have explained what was going on when I experienced engine trouble.