Monitor 122.0 for current reports. Density altitude is a crucial criterion that determines the performance capabilities of an aircraft. Air density decreases with altitude. The further effects of high temperature and high humidity are cumulative, resulting in an increasing high density altitude which reduces all aircraft performance parameters. If the CG is set to the forward position, a stall will be encountered at a higher than normal stall airspeed configuration.
Density altitude is the altitude at which the aircraft thinks it is and performs accordingly.
Full power leaning may be necessary for takeoff and landing procedures with normally aspirated engines. Most turbocharged reciprocating engines require full rich mixture prior to takeoffs and landings. There may be occasions when it will be necessary to climb to an altitude where oxygen is required by regulation. Portable oxygen comes in very handy at these times. Review FAR 91.211.