Emergency Locator Transmitter Activation Device for Enhanced Emergency Location Performance

• US 20170248676A1
• Filed: 02/25/2016
• Published: 08/31/2017
• Est. Priority Date: 02/25/2016
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Murphy, Timothy A., Adler, Charles O., Khalil, Fadl I.
• Granted Patent: US 10,450,084 B2
• Time in Patent Office: Days
• CPC Class Codes: B64D 2045/0065 Black boxes, devices automatically broadcasting distress signals
• CPC Class Codes: B64D 45/00 Aircraft indicators or protectors not otherwise provided for camouflage F41H3/00
• CPC Class Codes: G01S 1/08 Systems for determining direction or position line
• CPC Class Codes: G01S 1/68 Marker, boundary, call-sign, or like beacons transmitting signals not carrying directional information
• CPC Class Codes: G01S 19/17 Emergency applications
• CPC Class Codes: G01S 5/0231 Emergency, distress or locator beacons

Abstract

An aircraft avionics unit that enhances the emergency location capability of existing Emergency Locator Transmitters (ELTs). This aircraft avionics unit can be integrated with a wide range of existing ELTs and their existing aircraft interfaces by changes to a small number of the signal wires between the ELT and the aircraft systems and the addition of limited inputs from aircraft systems. This system requires no changes to either the current ELTs or the associated aircraft systems. The integrated system maintains the current ELT concept of operations while providing significantly enhanced ELT activation triggering with a low-impact, low-cost approach.

Claims

1. A method for enhancing an emergency locator transmitter system on an aircraft, the emergency locator transmitter (ELT) system comprising an antenna, an emergency locator transmitter having a radio frequency signal port connected to the antenna, and an ELT remote panel that has a manually operable switch, the method comprising:

(a) connecting the switch of the ELT remote panel to a first input data port of an activation/trigger device by wiring; and

(b) connecting a first output data port of the activation/trigger device to an input data port of the emergency locator transmitter by wiring.

2. The method as recited in claim 1, wherein step (a) comprises connecting the first input data port of the activation/trigger device to wiring that connects the switch of the ELT remote panel to the input data port of the emergency locator transmitter.

3. The method as recited in claim 2, wherein step (b) comprises connecting the first output data port of the activation/trigger device to the wiring that connects the switch of the ELT remote panel to the input data port of the emergency locator transmitter.

4. The method as recited in claim 1, wherein step (b) comprises connecting the first output data port of the activation/trigger device to wiring that connects the switch of the ELT remote panel to the input data port of the emergency locator transmitter.

5. The method as recited in claim 1, further comprising connecting a second input data port of the activation/trigger device to receive inputs from an output data port of an aircraft avionics system.

6. The method as recited in claim 5, wherein the inputs from the output data port of the aircraft avionics system comprise aircraft discrete inputs.

7. The method as recited in claim 5, wherein the inputs from the output data port of the aircraft avionics system comprise aircraft navigation inputs.

8. The method as recited in claim 5, wherein the activation/trigger device is configured with activation logic that determines whether, based on inputs from aircraft avionics systems and ELT crew activation inputs from the switch of the ELT remote panel, an ELT activation signal should be sent to the emergency locator transmitter or not.

9. A system onboard an aircraft comprising:

an ELT remote panel on a flight deck of the aircraft, the ELT remote panel comprising a switch;

an antenna that is attached to an exterior of a fuselage skin of the aircraft;

an emergency locator transmitter connected to the antenna; and

an activation/trigger device connected to the switch of the ELT remote panel and to the emergency locator transmitter.

10. The system as recited in claim 9, wherein the emergency locator transmitter is also connected to the switch of the ELT remote panel.

11. The system as recited in claim 9, further comprising an aircraft avionics system connected to the activation/trigger device.

12. The system as recited in claim 11, wherein the activation/trigger device is configured with activation logic that determines whether, based at least in part on inputs from the aircraft avionics system and ELT crew activation inputs from the switch of the ELT remote panel, an ELT activation signal should be sent to the emergency locator transmitter or not.

13. The system as recited in claim 12, wherein the inputs from the output data port of the aircraft avionics system comprise aircraft discrete inputs.

14. The system as recited in claim 12, wherein the inputs from the output data port of the aircraft avionics system comprise aircraft navigation inputs.

15. A system onboard an aircraft comprising:

a manually operable switch incorporated in a flight deck panel;

an antenna that is attached to an exterior of a fuselage skin of the aircraft;

an emergency locator transmitter having a radio frequency signal port connected to the antenna; and

an activation/trigger device connected to the switch of the ELT remote panel by wiring and connected to the emergency locator transmitter by wiring.

16. The system as recited in claim 15, wherein the emergency locator transmitter is also connected to the switch of the ELT remote panel by wiring.

17. The system as recited in claim 15, further comprising an aircraft avionics system connected to the activation/trigger device.

18. The system as recited in claim 17, wherein the activation/trigger device is configured with activation logic that determines whether, based at least in part on inputs from the aircraft avionics system and ELT crew activation inputs from the switch of the ELT remote panel, an ELT activation signal should be sent to the emergency locator transmitter or not.

19. An emergency locator transmitter (ELT) activation/trigger device comprising:

first processing means comprising ELT activation logic; and

an input interface comprising first, second and third terminals and second processing means configured to output an ELT ON state signal to the ELT activation logic if an impedance between the first and third terminals is effectively zero or if an impedance between the first and second terminals is effectively zero.

20. The ELT activation/trigger device as recited in claim 19, wherein the input interface further comprises:

a high-impedance buffer circuit connected to the first, second and third terminals; and

an analog-to-digital converter between the high-impedance buffer circuit and the second processing means.

21. The ELT activation/trigger device as recited in claim 19, wherein the first processing means further comprises an aircraft behavior state estimator and trigger logic that receives an estimated aircraft behavior state signal from the aircraft behavior state estimator and the ELT ON state signal from the second processing means, and is configured to send an ELT activation request signal to the ELT activation logic if the estimated aircraft behavior state signal indicates an abnormal or distress state or an ELT ON state signal has been received.