Robert C Moffitt

US Patent:

6666648, Dec 23, 2003

Filed:

May 17, 2002

Appl. No.:

10/150823

Inventors:

Andreas P. F. Bernhard - Shelton CT
Michael S. Torok - Hamden CT
Robert C. Moffitt - Seymour CT
Peter F. Lorber - Coventry CT
Geoffrey C. R. Davis - Madison CT
William Arthur Welsh - New Haven CT
Brian E. Wake - South Glastonbury CT

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 2735

US Classification:

416 23, 416134 R, 384221

Abstract:

An elastomeric coupler assembly having a helical elastomeric bearing movably supports an active slat relative to a main element. An inner elastomeric coupler assembly and an outer elastomeric coupler assembly support the slat therebetween. Centrifugal force operates to drive the slat to a first position and an actuator rod operates in tension to pull upon the inner elastomeric coupler assembly to drive the slat in opposition to the centrifugal force to a second position. The helical elastomeric bearing is layered such that it defines a section of a circular helix. The circular helix provides a coupling, which converts a linear input parallel to a virtual hinge axis into a rotary output to pitch the slat. In operation, centrifugal force operates to slide the slat outboard toward the blade tip such that the attached slat moves elastomerically along the helical arc of the helical elastomeric bearing to rotate the slat nose down. To retract the slat, the actuator operates to place the actuator rod under tension to pull upon the active member and retract the slat in opposition to centrifugal force.

US Patent:

6769872, Aug 3, 2004

Filed:

May 17, 2002

Appl. No.:

10/147558

Inventors:

Michael S. Torok - Cheshire CT
Robert C. Moffitt - Seymour CT
Peter F. Lorber - Coventry CT
Geoffrey C. R. Davis - Madison CT
Andreas P. F. Bernhard - Shelton CT
William Arthur Welsh - New Haven CT
Brian E. Wake - South Glastonbury CT

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 27615

US Classification:

416 1, 416 24, 416 98

Abstract:

A multi-element rotor blade includes a main element and an active slat movable relative to the main element. The slat rotates and translates relative to the main element from a base position. The base position provides a compromise between minimum coefficient of drag C and maximum coefficient of lift C. In the advancing blade, since the airspeed thereof is significantly greater than the retreating blade, the slat is positively rotated from the base position to minimizes drag at low angles of attack. In the retreating blade, since the airspeed thereof is significantly lower than the advancing blade, the slat is negatively rotated and translated to maximize the coefficient of lift C.

US Patent:

6840741, Jan 11, 2005

Filed:

Oct 14, 2003

Appl. No.:

10/685220

Inventors:

Brian E. Wake - South Glastonbury CT, US
Peter F. Lorber - Coventry CT, US
Robert C. Moffitt - Seymour CT, US
Ray-Sing Lin - Glastonbury CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 1118

US Classification:

416227A, 416223 R, 416228, 416231 B, 416236 R, 416243, 416DIG 2

Abstract:

A leading edge slat for multi-element rotor blade applications which provide multiple benefits and provide design direction which has heretofore been unexplored.

US Patent:

6932569, Aug 23, 2005

Filed:

Dec 27, 2002

Appl. No.:

10/331107

Inventors:

Michael S. Torok - Cheshire CT, US
Robert C. Moffitt - Seymour CT, US
Ashish Bagai - Hamden CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C011/18

US Classification:

416 1, 416 24, 416155, 416231 B

Abstract:

A multi-element rotor blade includes an individually controllable main element and fixed aerodynamic surface in an aerodynamically efficient location relative to the main element. The main element is controlled to locate the fixed aerodynamic surface in a position to increase lift and/or reduce drag upon the main element at various azimuthal positions during rotation.

US Patent:

7252479, Aug 7, 2007

Filed:

May 31, 2005

Appl. No.:

11/140706

Inventors:

Ashish Bagai - Hamden CT, US
Robert C. Moffitt - Seymour CT, US
Timothy A. Krauss - Harwinton CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 27/46

US Classification:

416223R, 416238, 416DIG 2, 416DIG 5

Abstract:

A main rotor blade exhibiting a unique planform shape in which the blade chord increases from the root end of the blade inboard region to the outer main region of the blade, where the blade chord achieves a maximum chord at a spanwise location within the main region, then decreases toward a distal tip end. The leading edge preferably is generally straight while the trailing edge is contoured to define the chord. Another characteristic feature of the rotor blade design is the location of the blade-feathering axis in which the feathering axis is located at a mid chord position over some inboard length of the rotor blade then transitions to a quarter chord location. Another characteristic feature is an airfoil distribution along the blade span that transitions from a blunt trailing edge to a sharp trailing edge airfoil suited for mid-range Mach number operation. The tip region preferably utilizes a transonic flow airfoil. Another characteristic feature of the rotor blade design is an unconventional combination of positive and negative twist gradients.

US Patent:

7513750, Apr 7, 2009

Filed:

Mar 8, 2006

Appl. No.:

11/370407

Inventors:

Robert C. Moffitt - Seymour CT, US
Thomas Alan Egolf - Glastonbury CT, US
Robert D. Beatty - Trumbull CT, US
John K. Karpowich - Trumbull CT, US
Ashish Bagai - Hamden CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 27/46

US Classification:

416228

Abstract:

A main rotor blade incorporating a rotor blade tip region having a tip chord and a tip taper such that the ratio of the main rotor blade chord to the tip chord is approximately 0. 30. The tip taper ratio preferably providing an approximately 28% area of reduction in said outer 10% of said blade span. The tip region preferably further including a hover optimized high lift airfoil and a tip sweep that reaches a constant value of approximately 30 degrees along the quarter chord line.

US Patent:

7547193, Jun 16, 2009

Filed:

Jul 22, 2005

Appl. No.:

11/187663

Inventors:

Robert Moffitt - Seymour CT, US
James E. Duh - Derby CT, US
Charles Berezin - Trumbull CT, US

Assignee:

Sikorsky Aircraft Corporation - Stratford CT

International Classification:

B64C 27/46

US Classification:

416228, 416223 R, 416237, 416DIG 5

Abstract:

A main rotor blade assembly with a high negative pitching moment airfoil section having a pitching moment coefficient beyond (more negative than) −0. 035 at Mach Numbers below 0. 80 and a blade taper of 1:5 or greater. The main rotor blade preferably limits blade torsional bending and an aft loaded tip airfoils to approximately ‘no more’ than that of conventional effective rotor blade designs based on conventional tip airfoil sections.

US Patent:

20050281676, Dec 22, 2005

Filed:

Jun 16, 2004

Appl. No.:

10/869799

Inventors:

Thomas Egolf - Glastonbury CT, US
Robert Moffitt - Seymour CT, US

International Classification:

B63H001/26

US Classification:

416228000

Abstract:

A rotary-wing includes a multi-hedral tip section which utilizes a distribution of anhedral and/or dihedral angles that cause a tip vortex to be axially displaced relative to a region on a following blade such that the tip vortex generally avoids influence upon the following blade.