VARIABLE ENGINE-INLET BYPASS CONTROL METHOD AND SYSTEM

1 . A method of optimizing engine air-mass-flow intake of an aircraft, the method comprising:

determining air mass flow (“M 1 ”) at a forward-facing airframe inlet duct, the forward-facing airframe inlet duct comprising a sliding air-mass-flow bypass door;

determining required air mass flow (“MW”) of an engine coupled to the forward-facing airframe inlet duct;

determining an air-mass-flow difference (“M 3 ”) between M 1 and MR; and

adjusting the sliding air-mass-flow bypass door to pass M 3 such that at least a portion of M 3 does not reach the engine.

2 . The method of claim 1 , comprising:

obtaining air data; and

determining required engine power.

3 . The method of claim 1 , wherein M 1 is dependent on airspeed, air density, and an area of the forward-facing airframe inlet duct.

4 . The method of claim 1 , comprising repeating the steps of claim 1 of determining M 1 , determining MR, determining M 3 between M 1 and MR, and adjusting the sliding air-mass-flow bypass door.

5 . The method of claim 2 , wherein the air data comprises outside ambient temperature, altitude, and airspeed.

6 . The method of claim 2 , wherein the air data comprises at least one of outside ambient temperature (“OAT”), altitude, and airspeed.

7 . (canceled)

8 . (canceled)

9 . The method of claim 2 , wherein the required engine power is determined using at least one of developmental test data and analytical data and at least some of the air data.

10 . The method of claim 2 , wherein the determined required air mass flow is dependent on the determined required engine power.

11 . (canceled)

12 . A computer-program product comprising a non-transitory computer-usable medium having computer-readable program code embodied therein, the computer-readable program code adapted to be executed to implement a method of optimizing engine air-mass-flow intake of an aircraft, the method comprising:

determining air mass flow (“M 1 ”) at a forward-facing airframe inlet duct, the forward-facing airframe inlet duct comprising a sliding air-mass-flow bypass door;

determining required air mass flow (“MR”) of an engine coupled to the forward-facing airframe inlet duct;

determining an air-mass-flow difference (“M 3 ”) between M 1 and MR; and

adjusting the sliding air-mass-flow bypass door to pass M 3 such that at least a portion of M 3 does not reach the engine.

13 . The computer-program product of claim 12 , the method comprising:

obtaining air data;

determining required engine power; and

wherein the determined required air mass flow is dependent on the determined required engine power.

14 . The computer-program product of claim 12 , wherein M 1 is dependent on airspeed, air density, and an area of the forward-facing airframe inlet duct.

15 . The computer-program product of claim 12 , the method comprising repeating the steps of claim 12 .

16 . The computer-program product of claim 13 , wherein the air data comprises outside ambient temperature, altitude, and airspeed.

17 . The computer-program product of claim 13 , wherein the air data comprises at least one of outside ambient temperature (“OAT”), altitude, and airspeed.

18 . The computer program product of claim 12 , wherein M 3 is directed to a location of the aircraft where a drag impact thereof is minimized.

19 . The computer-program product of claim 13 , wherein:

at least a substantial amount of M 3 is routed into a compartment of the aircraft at a greater ambient temperature than a temperature of M 3 ; and

the required engine power is determined using at least one of developmental test data and analytical data and at least some of the air data.

20 . A system for optimizing engine air-mass-flow intake of an aircraft, the system comprising:

a forward-facing airframe-inlet duct interoperably coupled to an inlet of an engine of the aircraft;

a sliding bypass door coupled to the forward-facing airframe-inlet duct and adjustable to allow a selected amount of air entering an inlet of the forward-facing airframe-inlet duct to bypass the inlet of the engine;

an air-pressure sensor arranged in the forward-facing airframe-inlet duct; and

wherein a measured value (“PT 1 ”) from the air-pressure sensor is used to determine a degree to which the sliding bypass door is to be opened.