400-ft/NM descent gradient

On this kind of approach, the path is built so the aircraft loses no more than 400 feet of altitude for each nautical mile flown forward. It is the standard slope used when designing the approach.

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Monday, June 15, 2026static system and encoder certificationA test that proves the aircraft's altitude-sensing plumbing and the device that sends altitude data to air traffic control are working correctly. It must be done every 24 calendar months for IFR flight in controlled airspace.
Sunday, June 14, 2026Combined Vision SystemsA cockpit display that combines two views into one: a computer drawing of the terrain and runway based on a stored map, and a live camera or infrared picture of what is actually in front of the aircraft. Together they give the pilot a clearer picture in poor visibility than either view alone.
Saturday, June 13, 2026thermal anti-ice systemA system that warms key parts of the aircraft so ice cannot form on them in the first place.
Friday, June 12, 2026civil aviationAny flying that isn't done by the military. That covers everything from airline flights and cargo runs to private pilots, flight schools, and crop dusters.
Thursday, June 11, 2026empennageThe whole tail assembly of the airplane — the fin sticking up, the small wing-like surfaces sticking out the back, and the moving control surfaces attached to them.
Wednesday, June 10, 2026center of gravityThe single balance point of the aircraft. It is the spot where the airplane's weight is effectively centered, and it has to stay within a defined range for the airplane to fly and handle properly.
Tuesday, June 9, 2026longitudinal axisA straight line drawn through the airplane from nose to tail. When the airplane tips one wing down and the other up, it is rotating around this line.
Monday, June 8, 2026PickA small pointed tool that mechanics use to poke, lift out, or pry loose tiny parts that can't be grabbed with fingers or pliers.
Sunday, June 7, 2026terrainThe shape and features of the ground below — how high or low it is, whether it is flat, hilly, or mountainous, and what is on it.
Friday, June 5, 2026empennageThe whole tail assembly of the airplane — the fin sticking up, the small wing-like surfaces sticking out the back, and the moving control surfaces attached to them.
Thursday, June 4, 2026density altitudeHow thin or thick the air actually feels to the airplane right now, expressed as an altitude. On a hot day at a low airport, the air can feel as thin as the air thousands of feet higher up, and the airplane performs as if it were up there.