power graphs intro
TRANSCRIPT
POWER GRAPHSPOWER GRAPHS
TOTAL DRAG (thrust required)
• Minimum drag speed
• Influence of weight
• Influence of altitude
POWER REQUIRED
• Minimum power required speed
• Influence of weight
• Influence of altitude
POWER AVAILABLE
• Influence of altitude
• Minimum and maximum speeds
SUMMARYSUMMARY
Induced drag decreases with speed, whilst parasite drag increases.
Flying at the minimum drag speed, parasite drag equals induced drag.
The minimum drag speed corresponds to max. L/D ratio speed.
If weight is increased, the minimum drag speed will be higher.
In terms of EAS, the minimum drag speed does not change with altitude.
In terms of TAS, the minimum drag speed increases with altitude, but the minimum drag value remains constant.
POWER REQUIREDPOWER REQUIRED
Pr
Ve
MINIMUM POWER REQUIRED
MINIMUM DRAG
(MAX L/D RATIO)
POWER = DRAG x SPEED
SUMMARYSUMMARY
The minimum power speed is lower than the minimum drag speed.
More weight obviously increases the power required.
Although the minimum power required increases with altitude, the minimum power required speed (EAS) remains constant.
Both minimum power required speed and minimum drag speed increase with altitude in terms of TAS.