Thomas Wilson Griffith

US Patent:

62413252, Jun 5, 2001

Filed:

Oct 14, 1997

Appl. No.:

8/950130

Inventors:

John J. Gowan - Mountlake Terrace WA
Thomas T. Griffith - Seattle WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

B60T 868

US Classification:

303176

Abstract:

A low-speed antiskid control for a multigain hydraulic valve brake system for an airplane is disclosed. The antiskid control includes low- and high-pressure bias modulation (PBM) high step thresholds. At high speeds the low PBM threshold is used to control a PBM high step firing. At low speeds, the high PBM threshold is used to prevent a PBM high step firing unless a deep skid is occurring. The use of a high threshold at low airplane speeds prevents a low speed control loss due to PBM high step firing reducing brake pressure to below minimum brake contact pressure.

US Patent:

55055311, Apr 9, 1996

Filed:

May 12, 1995

Appl. No.:

8/440161

Inventors:

Thomas T. Griffith - Seattle WA
David T. Yamamoto - Bothell WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

B60T 886

US Classification:

303126

Abstract:

An aircraft autobrake system utilizes a hydraulic fluid pressure sensor to provide a signal proportional to brake hydraulic fluid pressure magnitude to a control system. The control system uses closed loop feedback of this pressure signal to control autobrake application. Such control avoids pressure or deceleration overshoot or undershoot caused by not achieving brake stack closure when deceleration control is applied. Upon landing, if autobrake control command plus the change in autobrake control command necessary to eliminate deceleration error is less than a specified minimum, then brake stack closure needs to be maintained. In that case, the control system determines hydraulic fluid pressure error and adjusts hydraulic fluid pressure to eliminate such pressure error, using closed loop feedback. Upon elimination of pressure error, indicating brake stack closure, deceleration control then applies autobraking to slow the aircraft without pressure or deceleration overshoot or undershoot. If upon landing, the autobrake control command plus the change in autobrake control command necessary to eliminate deceleration error is greater than a specified minimum, then deceleration control is used to apply braking and decelerate the aircraft.

US Patent:

61425850, Nov 7, 2000

Filed:

Oct 14, 1997

Appl. No.:

8/949415

Inventors:

John J. Gowan - Mountlake Terrace WA
Trent D. Miller - Renton WA
Jay S. Kallaher - Renton WA
Thomas T. Griffith - Seattle WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

B60T 886

US Classification:

303126

Abstract:

At low speeds, an antiskid/autobrake control system applies a brake release current to the antiskid valves of the brake system associated with selected wheels of an airplane to prevent brake shudder caused by gear walk. The control system obtains a measured wheelspeed value from each of the selected wheels and calculates a reference wheelspeed based the measured wheelspeed. Tests are made to determine if the reference wheelspeed is below some predetermined magnitude, e. g. , 15 knots, and if the airplane ground speed is below some predetermined magnitude, e. g. , 50 knots. If the tests are passed, the value of a low-speed brake release current to be applied to the antiskid valves of the airplane's brake system is determined. In order to prevent an abrupt change in braking, the low-speed brake release value ramps off as the airplane slows to a stop. Releasing some of the brakes results in the pilot increasing pressure on the remaining brakes, thereby eliminating brake shudder due to gear walk.

US Patent:

20180134265, May 17, 2018

Filed:

Jan 12, 2018

Appl. No.:

15/870665

Inventors:

- Chicago IL, US
Bruce Lam - Everett WA, US
David T. Yamamoto - Seattle WA, US
Thomas Todd Griffith - Seattle WA, US

International Classification:

B60T 8/17
B60T 8/00
B60T 8/32
B64C 25/42

Abstract:

A system, method, and apparatus for brake load alleviation amongst at least one first brake and at least one second brake is disclosed. The method involves sensing an amount of brake pedal application in response to engagement of at least brake pedal. The method further involves determining whether the amount of brake pedal application is greater than a brake pedal application threshold value. Also, the method involves generating a brake application profile, when it is determined that the amount of brake pedal application is greater than the brake pedal application threshold value. The brake application profile indicates that actuation of at least one first brake is delayed by a first time delay, and that actuation of at least one second brake is delayed by a second time delay. Further, the method involves actuating at least one first brake and at least one second brake according to the brake application profile.

US Patent:

20180122250, May 3, 2018

Filed:

Nov 3, 2016

Appl. No.:

15/343164

Inventors:

- Chicago IL, US
Nima Forghani - Seattle WA, US
Thomas Todd Griffith - Seattle WA, US

International Classification:

G08G 5/06

Abstract:

An automatic braking system controller automatically decelerates an aircraft on a runway according to a brake-to-exit or a constant deceleration function. The automatic braking system controller determines whether the aircraft can decelerate to a selected velocity prior to reaching a target location along the runway. In response to determining that the aircraft can decelerate to the selected velocity prior to reaching the target location, the automatic braking system controller automatically decelerates the aircraft with a comfortable deceleration profile such that the aircraft reaches the selected velocity at the target location.

US Patent:

20150120098, Apr 30, 2015

Filed:

Oct 28, 2013

Appl. No.:

14/064804

Inventors:

- Chicago IL, US
Jean Marie Crane - Seattle WA, US
Marisa R. Jenkins - Seattle WA, US
John David Anderson - Auburn WA, US
Thomas Todd Griffith - Seattle WA, US
Bechara J. Mallouk - Mukilteo WA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G08G 5/02

US Classification:

701 16

Abstract:

A system and method for determining a predicted stopping performance of an aircraft moving on a runway. A predicted stopping force acting on the aircraft to stop the aircraft is determined by a processor unit as the aircraft is moving on the runway. A predicted deceleration of the aircraft moving on the runway is determined by the processor unit using the predicted stopping force acting on the aircraft to stop the aircraft. The predicted stopping performance of the aircraft on the runway is determined by the processor unit using the predicted deceleration of the aircraft.

US Patent:

20150088371, Mar 26, 2015

Filed:

Sep 26, 2013

Appl. No.:

14/038504

Inventors:

- CHICAGO IL, US
Bruce Lam - Everett WA, US
David T. Yamamoto - Seattle WA, US
Thomas Todd Griffith - Seattle WA, US

Assignee:

THE BOEING COMPANY - CHICAGO IL

International Classification:

B60T 8/17
B60T 8/32

US Classification:

701 339, 701 70

Abstract:

A system, method, and apparatus for brake load alleviation amongst at least one first brake and at least one second brake is disclosed. The method involves sensing an amount of brake pedal application in response to engagement of at least brake pedal. The method further involves determining whether the amount of brake pedal application is greater than a brake pedal application threshold value. Also, the method involves generating a brake application profile, when it is determined that the amount of brake pedal application is greater than the brake pedal application threshold value. The brake application profile indicates that actuation of at least one first brake is delayed by a first time delay, and that actuation of at least one second brake is delayed by a second time delay. Further, the method involves actuating at least one first brake and at least one second brake according to the brake application profile.