Flight Dynamics - Section 4 - part2 - Summary of Basic Points of the Flight Envelope

1. Equivalent speed-altitude-thrust relationship of jet aircraft

Equivalent velocity definition: $V_e=V\sqrt{\frac{}{r_0}}$

• Thrust decreases with height
• Minimum speed $V_{min}$increases with height
• Maximum speed $V_{max}$Decreases with height
  

2. Equivalent velocity-height relationship

When the minimum speed is consistent with the maximum speed, it is the theoretical upper limit altitude that the aircraft can reach, which is called the absolute ceiling.

3. True speed-altitude relationship

The real speed is slightly larger than the equivalent speed, so its schematic diagram is as follows:

4. References

Flight Dynamics - Section 4 - part2 - Flight Envelope