PTAB

IPR2019-01489

General Electric Co v. United Technologies Corp

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Turbofan Engine Inlet and Fan Dimensional Relationship
  • Brief Description: The ’653 patent relates to a turbofan engine assembly featuring a specific dimensional relationship between the engine’s inlet length (L) and its fan diameter (D). The patent claims an L/D ratio between 0.2 and 0.45, asserting this is smaller than on typical engines and provides benefits such as reduced weight, lower external drag, and improved structural clearance.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 2, 8-10, 15, 17, and 18 under 35 U.S.C. §102

  • Prior Art Relied Upon: (Howe) (NASA Report CR-1/4942, May 1985).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Howe, a 1985 NASA report describing work on the "Energy Efficient Engine" ("EEE") program, fully anticipates the key limitations of the challenged claims. The report describes an advanced turbofan engine, the STF653, which features a "short, slim nacelle" for fuel savings. For the STF653 engine, Howe explicitly disclosed a ratio of inlet length to fan diameter (LINLET/DFAN) of 0.291, which falls squarely within the ’653 patent's broadest claimed range of 0.2 to 0.45. Petitioner further asserted that Howe discloses a bypass ratio of 12.8, satisfying claims requiring a ratio greater than 6 and greater than 10. For independent claim 15, Howe's disclosure of a "geared" fan drive was argued to teach the claimed geared architecture. Other limitations, such as the fan comprising a plurality of blades with leading edges, were asserted to be either explicitly or inherently disclosed in Howe's text and detailed figures.
    • Key Aspects: The core of this ground rested on a direct numerical disclosure in a table within Howe that mapped to the primary limitation of the ’653 patent.

Ground 2: Obviousness of Claims 14 and 20 over Howe in view of Gray

  • Prior Art Relied Upon: Howe (NASA Report CR-1/4942, May 1985) and (Gray) (NASA CR-174766, Oct. 1983).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that dependent claims 14 and 20, which require a geared architecture with a "gear reduction ratio greater than or equal to 2.3," were obvious over the combination of Howe and Gray. While Howe teaches that its STF653 engine has a "geared" fan drive, it does not disclose the specific gear ratio. However, Gray, a related report from the same NASA EEE program, describes the same engine (identifying it as "candidate 1") and explicitly discloses its "overall gear ratio is 3.12:1." This value meets the claimed limitation of being greater than 2.3.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) researching the STF653 engine in Howe would be motivated to consult Gray for more detailed parameters. The motivation is strong because both references originate from the same EEE program, describe the same engine, were authored by employees of the Patent Owner, and Howe explicitly cites Gray as a source.
    • Expectation of Success: A POSITA would have a high expectation of success in combining the teachings, as they are complementary descriptions of the identical engine.

Ground 3: Obviousness of Claims 1-4 and 8-20 over Heidelberg in view of Wendus

  • Prior Art Relied Upon: (Heidelberg) (NASA Lewis Research Center Report, Dec. 1992) and (Wendus) (NASA Report CR2003-212467, Aug. 2003).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued this combination renders all claims obvious. Heidelberg, an acoustic study on turbofan engine inlets, tested three different inlet lengths on an "Advanced Ducted Propeller" (ADP) engine. It explicitly disclosed resulting L/D ratios of 0.21 and 0.41, both of which fall within the ’653 patent's claimed range of 0.2-0.45. While Heidelberg focused on acoustics and did not detail the ADP engine's internal structure, Wendus provides these missing specifications for the same ADP engine. Wendus discloses a bypass ratio of 16.7, a geared architecture driving the fan, and a gear reduction ratio of 4.2, thereby teaching the remaining limitations of the challenged claims.
    • Motivation to Combine: A POSITA reviewing Heidelberg's acoustic data for different inlet lengths would be naturally motivated to consult a reference like Wendus to understand the specific design and performance characteristics of the ADP engine being tested. The references are complementary, with Wendus supplying the engine details necessary to fully understand the context of Heidelberg's acoustic tests.
    • Expectation of Success: A POSITA would have a high expectation of success, given that both references expressly concern the same advanced engine concept (the ADP engine).
  • Additional Grounds: Petitioner asserted additional obviousness challenges, including that claims 5-7 are obvious over Howe in view of (Ruehr) (Patent 4,220,171) for teaching a drooped inlet design. An additional ground based on Heidelberg and Wendus in view of (Wynosky) (Patent 4,722,357) was also noted but omitted from the main petition for brevity.

4. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-20 of Patent 9,920,653 as unpatentable.