On-board water spray system for aircraft

Patent metadata

Field	Value
Publication number	US-9566597-B2
Application number	US-201414270301-A
Country	US
Kind code	B2
Filing date	May 5, 2014
Priority date	Apr 15, 2010
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

A system for simulating wet runway conditions by using a liquid container that is placed inside an aircraft. The liquid container is connected to a nozzle that sprays water in front of the wheels of the aircraft. A valve is used to control the flow of water from the nozzle. Systems, such as the braking system of the aircraft, can then be tested in wet runway conditions simulated by the system. The amount of water sprayed from the nozzle can also be electronically controlled in relation to the speed of the aircraft, such that the nozzle sprays a nearly uniform layer of liquid in front of the wheels. The system can also be modified to include two tanks to manipulate the center of gravity of the aircraft.

First claim

The invention claimed is:

1. A system for simulating wet runway conditions, comprising:
a first liquid tank situated on an aircraft;
a pressure source; and
a pressure conduit for providing pressure to the first liquid tank from the pressure source; and
a spray nozzle positioned in front of a wheel of the aircraft, and pressurized liquid from the first liquid tank flowing through the spray nozzle;
a control valve establishing a rate of flow of the pressurized liquid;
a pressure control subassembly in connection with the pressure source and pressure conduit, the pressure control subassembly preventing over-pressurization in the first liquid tank by releasing pressure when a predetermined amount of pressure is met;
a flow meter quantifying the rate of flow of the pressurized liquid;
a speed sensor measuring speed of the aircraft;
a controller connected to the control valve, the flow meter, and the speed sensor, and able to receive liquid flow information from the flow meter and speed of the aircraft from the speed sensor;
wherein the controller causes liquid to be sprayed onto the runway at an actual flow rate; the actual flow rate being within an acceptable range of deviation of an ideal flow rate; the ideal flow rate being proportional to the aircraft speed; the acceptable range of deviation increasing with increasing aircraft speed; and
an inter-tank fluid redistribution arrangement associated with the first liquid tank, the arrangement configured to enable the observation of aircraft performance under a range of varied center-of-gravity locations by pumping liquid to forward or backward locations on the aircraft.

2. The system of claim 1 , wherein the controller is in electronic communication with the control valve, the flow meter and the speed sensor.

3. The system of claim 2 , wherein the controller is further in electronic communication with a switch in a cockpit of the aircraft.

4. The system of claim 2 , wherein the controller is selected from the group consisting of: a personal computer, a programmable logic controller, a microcomputing device, and a single board device.

5. The system of claim 4 , wherein the spray nozzle is one of a plurality of spray nozzles, each spray nozzle being positioned in front of the wheel of the aircraft.

6. The system of claim 1 , wherein the spray nozzle emits the pressurized liquid in a substantially fan-shaped spray pattern.

7. The system of claim 1 , wherein a fluid control system transfers pressurized liquid from the first liquid tank to a second liquid tank and the second liquid tank to the first liquid tank to shift the initial center of gravity beyond a safe range of the center of gravity.

8. A system on an aircraft for simulating wet runway conditions, comprising:
a first liquid tank containing liquid, the first liquid tank being forwardly located relative to the an initial center of gravity of the aircraft;
a second liquid tank containing liquid, the second liquid tank being rearwardly located relative to the initial center of gravity of the aircraft;
a regulated source of pressurized air pressurizing the liquid to pressurized liquid in the first and second liquid tanks;
a pressure control subassembly in connection with the first and second liquid tanks, the pressure control subassembly preventing over-pressurization in the first and second liquid tanks by releasing pressure when a predetermined amount of pressure is met; and
a fluid control system located on the aircraft, comprising:
a control valve establishing a rate of flow of the pressurized liquid;
a flow meter quantifying the rate of flow of the pressurized liquid;
a speed sensor measuring the speed of the aircraft; and
a controller connected to the control valve, the flow meter, and the speed sensor;

wherein the controller causes liquid from each of the first and the second liquid tanks to be sprayed onto a ground surface in front of an aircraft wheel; an actual flow rate of the liquid being sprayed on the ground surface at a particular aircraft speed being within an acceptable range of deviation from the ideal flow rate;
wherein the acceptable range of deviation of the actual flow rate from the ideal flow rate increases with increasing aircraft speed; and
an inter-tank fluid redistribution arrangement enabling liquid to be pumped forward to the first tank or backward to the second tank, the arrangement configured to enable the observation of aircraft performance under a range of varied center-of-gravity locations for the purpose of defining a safe range for center of gravity.

9. The system of claim 8 , wherein the controller is in communication with a switch in a cockpit of the aircraft, the switch operating between an on position and an off position.

10. The system of claim 9 , wherein the controller is selected from the group consisting of: a personal computer, a programmable logic controller, a microcomputing device, and a single board device.

11. A method for testing performance of an aircraft comprising steps:
a) providing a liquid spray system, comprising:
a first liquid tank situated on a proximal side of an initial center of gravity of the aircraft;
a second liquid tank situated on a distal side of the initial center of gravity of the aircraft such that the second liquid tank is both closer to a back of the aircraft and further away from a cockpit of the aircraft as compared to the first liquid tank; the second liquid tank being fluidly coupled to the first tank;
a regulated source of pressurized air to pressurized liquid in the first and second liquid tanks;
a first spray nozzle and a second spray nozzle, each being fluidly coupled to at least one of the first liquid tank and the second liquid tank; the first spray nozzle and the second spray nozzle respectively configured to spray pressurized liquid in front of a left wheel and a right wheel of the aircraft;
a flow meter;
a speed sensor for determining a speed of the aircraft;
a controller in communication with the flow meter, the speed sensor, and the first and second liquid tanks;

b) providing a speed of the aircraft to the controller;
c) causing a center of gravity of the aircraft to shift outside a safe range of the center of gravity while the aircraft is airborne by using the controller to cause liquid to be pumped from the first liquid tank into the second liquid tank and by using the controller to cause liquid to be pumped from the second liquid tank into the first liquid tank, so as to test the performance of the aircraft under a range of the center of gravity to define the safe range of the center of gravity;
d) providing a look up table tabulating an ideal flow rate at which liquid is to be deposited onto a ground surface; the ideal flow rate being proportional to a speed of the aircraft; and
e) using the controller to cause liquid from each of the first and the second liquid tanks to be sprayed onto the ground surface in front of the left and the right wheels; an actual flow rate of the liquid being sprayed on the ground surface at a particular aircraft speed being within an acceptable range of deviation from the ideal flow rate;
wherein the acceptable range of deviation of the actual flow rate from the ideal flow rate increases with increasing aircraft speed.

12. The system of claim 11 , wherein the first and the second spray nozzles emit the pressurized liquid in a substantially fan-shaped spray pattern.

13. A method for testing performance of an aircraft comprising steps:
a) providing a liquid spray system, comprising:
a first liquid tank situated on a proximal side of an initial center of gravity of the aircraft;
a second liquid ta

Assignees

• Textron Innovations Inc

Inventors

• Mckay Gary E

Classifications

• B60T17/221 Primary

  Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems (hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M) · CPC title

• B60T2210/12

  Friction · CPC title

• B60T8/56

  having means for changing the coefficient of friction · CPC title

• B05B12/126 Primary

  responsive to target velocity, e.g. to relative velocity between spray apparatus and target (B05B9/06 takes precedence) · CPC title

• B60T2270/406

  Test-mode; Self-diagnosis · CPC title