Method for displaying flight information

1. A method for displaying flight information, comprising:

displaying a first characteristic sign illustrating a speed vector of an aircraft;

determining a first longitudinal margin of maneuver of the aircraft as a load factor; and

displaying a second characteristic sign such that a position of the second characteristic sign relative to the first characteristic sign illustrates the first longitudinal margin of maneuver, wherein a distance between the first characteristic sign and the second characteristic sign is proportional to the first longitudinal margin of maneuver.

2. The method of claim 1 , wherein the first characteristic sign and the second characteristic sign are displayed in a heads-up display viewfinder.

3. The method of claim 1 , wherein the first longitudinal margin of maneuver is related to one of a pitch-up maneuver and a pitch-down maneuver of the aircraft.

4. The method of claim 1 , further comprising:

determining a second longitudinal margin of maneuver of the aircraft as a load factor, wherein the first longitudinal margin of maneuver is related to a pitch-up maneuver of the aircraft, and the second longitudinal margin of maneuver is related to a pitch-down maneuver of the aircraft; and

displaying an additional second characteristic sign such that a position of the additional second characteristic sign relative to the first characteristic sign illustrates the second longitudinal margin of maneuver.

5. The method of claim 4 , wherein

a distance between the first characteristic sign and the additional second characteristic sign is proportional to the second longitudinal margin of maneuver.

6. The method of claim 1 , wherein the second characteristic sign is displayed only when the determined first longitudinal margin of maneuver is less than a predetermined value.

7. The method of claim 1 , wherein the first longitudinal margin of maneuver is determined by selecting the smaller of a first load factor margin and a second margin.

8. The method of claim 7 , wherein:

the second margin corresponds to an angle of incidence margin, and

the angle of incidence margin is calculated from the following expression:

Δα=1−[( Nz/ΔNmax )*((α max −α)/(α−α0))],

wherein Δα is the angle of incidence margin, Nz is a load factor, ΔNmax is a maximum value of margin of maneuver depicted, α is a angle of incidence, αmax is a maximum angle of incidence, and α0 is a zero lift angle of incidence.

9. The method of claim 7 , wherein:

the second margin corresponds to a speed margin, and

the speed margin is calculated from the following expression:

Δ V =1−[( Nz+Kp ( Vmax+V )− Kd ( dV/dt ))/Δ Nmax],

wherein ΔV is the speed margin, Nz is a load factor, ΔNmax is a maximum value of margin of maneuver depicted, V is a speed of the aircraft, Vmax is a maximum speed of the aircraft, (dV/dt) is a derivative with respect to time of the speed V, and Kp and Kd are predetermined parameters.

10. A method for displaying flight information, comprising:

providing a heads-up display in an aircraft;

displaying a speed vector of the aircraft on the heads-up display;

determining a margin of maneuver of the aircraft based on a speed of the aircraft in a pitch-down maneuver and based on an angle of incidence of the aircraft in a pitch-up maneuver; and

displaying the margin of maneuver concurrently with the speed vector on the heads-up display.

11. The method of claim 10 , wherein the margin of maneuver is determined as a load factor.

12. The method of claim 10 , wherein:

the speed vector of the aircraft is indicated by a first characteristic sign on the heads-up display, and

the margin of maneuver is indicated by a second characteristic sign on the heads-up display.

13. The method of claim 12 , wherein a distance between the first characteristic sign and the second characteristic sign is proportional to the determined margin of maneuver.

14. The method of claim 12 , wherein the second characteristic sign is displayed only when the determined margin of maneuver is less than a predetermined value.