Best Angle-of-Climb:
- Max excess thrust results in the best angle of climb
- Occurs at L/Dmax for a jet
- Occurs below L/Dmax for a prop
Best Rate-of-Climb:
- Best rate of climb, or Vy, maximizes velocity to obtain the greatest gain in altitude over a given period of time
- Vy is normally used during climb, after all obstacles have been cleared
- It is the point where the largest power is available
- Occurs above L/Dmax for a jet
- Occurs at L/Dmax for a prop
Best Rate vs. Angle of Climb:
- Certain conditions will call for a specific climb profile (Vy or Vx)
- Advantages of Vy:
- More visibility over the cowling
- Faster time to climb
- Increased airflow over the engine while at high power
- More of a buffer from stall speeds
Factors Impacting Climb Performance:
- There are several factors which can impact climb performance:
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Aircraft Weight
- One of the most basic considerations with regard to aircraft performance is weight, as it is a principle of flight
- The higher the weight of an aircraft, the more lift will be required to counteract
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Temperature:
- Ambient air temperatures impacts your aircraft performance based on their physical properties
- Engines don't like to run hot and if they do then reduced throttle settings may be required
- Temperature is also a leading factor in determining the effect of air density on climb performance
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Air Density:
- Air density, and more specifically, density altitude, is the altitude which the aircraft "thinks" it is at
- Performance does not depend on the physical altitude, but rather the density altitude, and the higher the temperature, the higher that altitude
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Winds:
- Headwinds increase performance by allowing wind flow over the wings without any forward motion of the aircraft
- Tailwinds do the opposite
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Aircraft Condition:
- Smooth, parasite free wings produce the best lift
- Anything to interrupt the smooth flow of air or increase drag will require additional forward movement, or thrust, to overcome
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