Due to heavy haze, and because my instructor suggested that we might be wasting our time in the air today due to those conditions, I agreed that we should focus on some ground training. We covered weight and balance, airport signage, and stall entry, execution and recovery procedures.

The Cessna 172 has many stations which are used to determine the CG arm. Some of these are estimates. For example, the pilot can sit between station 34 and 46 depending on where the seat is adjusted. The copilot can have his/her own station as well. By performing the W&B calculations on each passenger, instead of adding the weights for the entire front seat positions, we get a more accurate W&B. Therefore, we did a W&B for our airplane and identified the point on the envelope.

Here's an example of W&B with full fuel, my instructor and I flying, along with a 50 lb. bag:

What	Weight	Arm	Moment
Aircraft	1642	38.1	62.6
Pilot	180	34	6.12
Copilot	237	36	8.532
Fuel	318	47.16	14.99
Bag	50	95	4.75
Total	2427	39.96	96.99

My instructor described the envelope and indicated that I should mind the position within the envelope throughout the flight and possibly move bags around as I fly along as fuel is consumed. Flying in the center of the envelope will result in the most efficient flight with best performance. Having a CG in the front of the envelope will make it easier to recover from stalls but may result in more pressure on the front gear during landing, resulting in possible firewall damage. An aft CG will make the airplane harder to control.

We discussed airport signage and runway incursions. He gave me a quiz which I didn't do too bad on, which asked questions and gave the signs that met those questions. More information is available from the AOPA Air Safety Foundation web site.

We also discussed stalls, which I have been practicing on the simulator. Entry to, execution of, and recovery from stalls were discussed. However, we will cover this in more detail in the air.

I am scheduled for the following training days: