T 1141/15 08-12-2017

I. The appeal by the opponents 1 to 5 (appellants I) and the patent proprietor (appellant II) are directed against the decision of the opposition division to maintain European patent No. 1 883 576 in amended form on the basis of auxiliary request 1 filed with letter dated 23 December 2014.

II. In its decision the opposition division held that the provisions of Article 123(2) EPC were not met for the subject-matter of claims 1 and 8 as granted, but that auxiliary request 1 was allowable in view of the following prior art:

A1: US-A-4784355;

A2: US-A-4892274;

A3: US-A-4867394.

Prior art document A4, which was filed after expiry of the 9-month period according to Article 99(1) EPC, and the late-filed evidence A5 to A8 of alleged public prior use by delivery of Airbus A330-301 aircraft serial number (MSN) 037 and registration on 31 December 1993 by Compagnie Air France Europe SA were not admitted into the opposition proceedings.

III. With its grounds of appeal, the appellants I filed documents A9 to A12 and Affidavits by their employee's, Jens Puschmann and Alex Calder, which together with A5 to A8 allegedly demonstrated beyond reasonable doubt that the delivery of Airbus A330-301 according to A5 to A8 constituted a public prior use of the claimed invention. Furthermore, photograph E1 and the Affidavit of Ian Whitehouse were filed as evidence of public prior use by the public first flight of the first Airbus A380, registered F-WWOW, on 27 April 2005.

IV. Oral proceedings before the board took place on 8 December 2017 in the absence of the opponents, as announced in their letter dated 7 November 2017.

The appellants I (opponents 1 to 5) requested in writing that the decision under appeal be set aside and the patent be revoked.

The appellant II (patent proprietor) requested that the decision under appeal be set aside and that the patent be maintained as granted (main request), or in the alternative, that the appeal of the appellants I be dismissed and the patent be maintained in amended form as allowed by the opposition division (auxiliary request 1), or that the patent be maintained in amended form on the basis of one of the auxiliary requests 2-7A as filed with letter dated 23 December 2014 or one of the auxiliary requests 2B, 2C, 4B, 4C, 7B, 7C as filed with letter dated 4 January 2016.

V. Claim 1 as granted reads as follows (the underlined portion was objected to under Article 100(c) EPC):

"A fairing system (100a; 100b), comprising: an airfoil (110a) having a trailing edge (112) and an airfoil section (111a; 111b) with a trailing edge portion (112a; 112b); and

a fairing (120a; 120b) mounted to the airfoil section (111a; 111b), the fairing (120a; 120b) having a longitudinal axis (L2; L3) and a fairing section (122a; 122b) extending along the longitudinal axis (L2; L3) forward and aft of the trailing edge portion (112a; 112b) of the airfoil section (111a; 111b), with the airfoil section (111a; 111b) corresponding to a planform projection of a segment of the fairing section (122a; 122b) on the airfoil (110a);

the airfoil (110a) including a movable surface (113a; 113b) and the fairing (120a; 120b) housing at least a portion of a drive mechanism (115) and/or support structure for the movable surface (113a; 113b);

characterized in that the fairing section (122a; 122b) has:

a wide portion (124a), at least part of the wide portion (124a) of the fairing section (122a; 122b) being located aft of the airfoil section (111a; 111b), the wide portion (124a) of the fairing section (122a; 122b) having a single spanwise width (W1) measured perpendicular to the longitudinal axis (L2; L3) of the fairing (120a; 120b) that is greater than or equal to a spanwise width (W2, W3, W4) of any other portion (124b-d) of the fairing section (122a, 122b); and/or

a first side (S1) and a second side (S2), each side (S1, S2) being laterally displaced from the longitudinal axis (L3), each side (S1, S2) having a point (P1, P2) of maximum curvature, the point (P1, P2) of maximum curvature for at least one of the first and second sides (S1, S2) being located aft of the airfoil section (111b)."

Claim 1 according to auxiliary request 1 differs from claim 1 of the main request in that the underlined term in the preamble is replaced by:

the airfoil (110a) including a movable surface (113a; 113b) and the fairing (120a; 120b) housing a drive mechanism (115) and the associated supports required to support and move the movable surface (113a)

Independent claim 8 according to auxiliary request 1 reads as follows:

"A method for making a fairing system (100a; 100b), comprising:

locating a fairing (120a; 120b) proximate to an airfoil (110a), the airfoil (110a) having a trailing edge (112) and an airfoil section (111a; 111b) with a trailing edge portion (112a; 112b), a section (122a; 122b) of the fairing (120a; 120b) extending along a longitudinal axis (L2; L3) of the fairing forward and aft of the trailing edge portion (112a; 112b) of the airfoil section (111a; 111b), the airfoil section (111a; 111b) corresponding to a planform projection of a segment of the fairing section (122a; 122b) on the airfoil (110a);

mounting the fairing (120a; 120b) to the airfoil (110a) so that:

(a) at least part of a wide portion (124a) of the fairing section (122a; 122b) is located aft of the airfoil section (111a; 111b), the wide portion (124a) of the fairing section (122a; 122b) having a single spanwise width (W1) measured perpendicular to the longitudinal axis (L2; L3) of the fairing that is greater than or equal to a spanwise width (W2, W3, W4) of any other portion (124b-d) of the fairing section (122a; 122b); or

(b) a point (P1, P2) of maximum curvature for at least one of a first side (S1) and a second side (S2) is located aft of the airfoil section (111a; 111b), the first side (S1) and the second side (S2) each being laterally displaced from the longitudinal axis (L3); or

(c) both (a) and (b);

the airfoil (110a) including a movable surface (113a; 113b) and mounting the fairing (120a; 120b) to the airfoil (110a) includes mounting a fairing (120a; 120b) that is configured to house a drive mechanism (115) and the associated supports required to support and move the movable surface (113a)."

VI. The appellants I (opponents 1 to 5) essentially argued as follows:

As regards contravention of Article 123(2) EPC with regard to claims 1 and 8 as granted, the proprietor's argument that the patent related to aerodynamic improvements to fairing systems for aerospace vehicles inferred that the invention related generally to fairings. This was inconsistent with the proprietor's arguments regarding inventive step where the proprietor drew a distinction between an engine pylon fairing and a flap support fairing and alleged that the drive mechanism and support structure for the flap housed by the fairing was crucial to the validity of granted claim 1. There was no link between the teaching of the specific embodiments of the application as filed and the specific fairings identified in the background section (page 1, lines 8-19) of the application as filed. The reference to "current fairings" in the specific embodiments would instead be interpreted by the skilled person as referring to fairings of the same type as those described in the specific embodiments to which claim 1 of the patent related: namely a fairing system which housed a drive mechanism and the associated supports required to support and move the movable surface (as detailed on page 7, lines 23 and 24).

As regards the link between the present invention and "existing aircraft" on page 11, lines 10-18, there were many existing aircraft at the date of the invention yet a specific current aircraft fairing was discussed in the "background" section of the application as filed and there was nothing to suggest to equate the two. As regards the link between embodiments of the invention and a retrofit of the fairing 20 shown in Figure 1, the application as filed made clear (page 1, lines 23-25) that the fairing 20 housed "portions of a support structure and a drive mechanism". Thus both the support structure and the drive mechanism were essential elements housed within the fairings and it was not envisaged that the invention would be applied to a fairing which housed, for example, openly a portion of the support structure for the movable surface.

Documents A9 to A11 and the Affidavits by opponent's employees, Jens Puschmann and Alex Calder, together with A5 to A8 demonstrated beyond reasonable doubt that the delivery of the related Airbus A330-301 aircraft constituted a public prior use of the claimed invention. This evidence was prima facie so highly relevant to prejudice the novelty of at least the independent claims of the patent as amended, so admission into the proceedings was requested.

The Affidavit of Ian Whitehouse confirmed that the photograph in E1 showed the outboard wing engine pylon having a fairing with a fairing extension that housed the flap support and flap drive mechanism for the wing trailing edge flap. Since this public prior use was prima facie so highly relevant to prejudice (in combination with A3) the inventive step of at least the independent claims of the patent as amended, admission of the evidence to the proceedings was requested.

The language of claim 1 of auxiliary request 1 was sufficiently clear without requiring the restrictive interpretation put forward by the opposition division. Claim 1 required only "at least part of the wide portion of the fairing section being located aft of the airfoil section" meaning that some part of the wide portion may be located forward of, or at, the trailing edge of the airfoil section. There was an important difference between language which stated that "the wide portion is a single spanwise width...", and the claimed feature that "the wide portion has a single spanwise width...", requiring that the wide portion included (not: was) the portion of maximum width of the fairing.

Claim 1 lacked novelty with respect to A1 or A2, which described a fairing system according to the preamble of claim 1. The characterising portion of claim 1 included three alternative features, namely:

i) "the fairing system has a wide portion ... having a single spanwise width ... greater than ... a spanwise width of any other portion of the fairing section",

ii) "the fairing system has a wide portion ... having a single spanwise width ... equal to a spanwise width of any other portion of the fairing section",

iii) "the fairing system has a first side and a second side, ... each side having a point of maximum curvature, the point of maximum curvature for at least one of the first and second sides being located aft of the airfoil section".

Each of the features i), ii) and iii), i.e. also their combination, was described in A1 (Fig.1) or A2 (Fig. 6) which showed that at least part of a wide portion of the fairing section having a single spanwise width as specified by features i), ii) was located aft of the airfoil section, and the point of maximum curvature for at least one of the two sides of the fairing section was located aft of the airfoil section (feature iii)).

According to T 818/93, a feature was disclosed (even if disclosed solely in the drawings) if the skilled person could clearly derive the structure and function from the drawings. T 748/91 demonstrated that it was part of the disclosure where the skilled person could conclude from the drawings that one dimension was evidently larger than another. In case of A1 and A2, which related to the design of flap systems, the disputed feature was the shape of the flap system fairing. The skilled person, an aerodynamicist who was used to looking at the shape of aircraft parts and interpreting their purpose, would look at the shape of the flap system fairings described in A1 and A2 and understand the requirements for their design.

The flap system fairings shown in Figure 1 of A1 had a tapered forward portion blending in a smooth fashion to a "wide portion" before blending rearwardly in a smooth fashion to a tapered aft portion. At least part of the wide portion of the fairing section was located aft of the airfoil section. Furthermore, it was apparent to the skilled person that the wide portion had a single spanwise width as claimed, i.e included the maximum spanwise width of the fairing section, and that the aft taper of the fairing section was more pronounced than the forward taper (as was conventional in the design of flap system fairings). Thus, the fairing section reached a maximum width at approximately the trailing edge of the airfoil section, and the sides of the fairing section had a maximum curvature aft of the airfoil section. No specific dimension, or ratio between two dimensions, was taken from Figure 1 of A1 to appreciate this fact.

The skilled aerodynamicist expected to find the maximum width of the fairing section at approximately the airfoil trailing edge, not least because of flap system packaging constraints. Furthermore, he appreciated the shape and the function of the flap fairing depicted in Figure 1 of A1, according to which the fairing section was to be brought close to the tapered aft portion over a relatively short distance so as to reduce profile drag without creating significant flow separation. Thus, the characterising features of claim 1 were taught by A1.

Without having to take a specific measurement, or ratio between two dimensions, from the figures, A2 showed a flap fairing having a parallel sided portion and tapering aft body portion. The skilled aerodynamicist was not surprised in observing that the flap fairings described in A2 were parallel sided along the majority of their length, which provided well-known advantages in terms of reduced manufacturing. He appreciated that A2 taught a flap fairing which was parallel sided (i.e. had equal maximum width) in the region of the airfoil trailing edge, and that the sides of the fairing had maximum curvature aft of the airfoil section.

Claim 1 as amended lacked an inventive step with respect to A1 or A2 in combination with A3. According to the contested decision, the skilled person would apparently not have considered the teachings of A3 in order to improve the aerodynamics of the fairing of A1 or A2, since a 'pylon fairing' and a 'flap support fairing' were somehow apparently aerodynamically different. However (see minutes, paragraph 7), the same aerodynamic laws were applicable to both fairings, as confirmed by the opponents' technical expert, Ian Whitehouse, at the oral proceedings. No evidence was provided by the proprietor or the opposition division to the contrary. A3 gave a clear teaching that a fairing having the shape shown in Figure 4 thereof provided an aerodynamic improvement when mounted to a wing. Making the fairing system described in any of A1 or A2 implicitly involved the steps of locating and mounting the fairing to the airfoil, so also claim 8 lacked an inventive step.

VII. The arguments of the appellant II (patent proprietor) may be summarised as follows:

The patent and the application on which it was based related to aerodynamic improvements to fairing systems for aerospace vehicles and did not disclose any structural of functional modifications, but merely modifications to the shape of the fairings, leading to improved aerodynamic efficiency. This was clear from the definition of the problem as provided in the "Background" section of the application as filed (see page 1, line 8, to page 2, line 2). Fairings were often mounted on the wing to house portions of the drive mechanisms and/or support structure that could not be enclosed in the wing. These generally streamlined fairings still created drag on the aircraft. This problem was solved by shaping the fairing such that its widest portion (as shown in Figures 2 to 6) or the point of maximum curvature (shown in Figure 7) was located aft of the airfoil section, resulting in "a drag reduction and/or lift increase over that of airfoils having current fairings" (first embodiment, page 6, lines 20-25; second embodiment, paragraph bridging pages 10 and 11, or page 11, lines 5-6) and "a favorable pressure gradient with respect to drag and/or lift as compared to current fairings" (page 7, lines 1-6). Thus, the application as filed clearly dealt exclusively with aerodynamic improvements due to the novel shape of the fairings. Consequently, the skilled person would understand that the modified aerodynamic shape could be applied to fairings in general. Since the skilled person was aware that fairings were mounted on the wing to house portions of the drive mechanisms and/or support structure that could not be enclosed in the wing, he would read these features into the fairing systems having the claimed aerodynamic shape. Moreover, it was stated in the application as filed (page 7, lines 28 ff) that the fairing system could include more or fewer pieces, and a fairing system 120b was shown in the drawings which was located outside of flap 113b.

In fact, the application as filed specifically made a connection (see page 11, lines 10-18) between the fairing systems having the novel shape with the wide portion and/or the point of maximum curvature aft of the trailing edge and the prior art fairings as discussed in the "Background" section. As explicitly mentioned, prior art fairings 20 as shown in Figure 1 could be removed and replaced by a fairing similar to the first or second fairing system 100a, 100b as discussed in connection with Figures 2-7. Given this clear disclosure of the combination of the contents of a prior art fairing with the exterior shape of a fairing constructed in accordance with the invention (also claimed in original claim 25), claims 1 and 8 as granted did not include added subject matter.

The contested decision focussed on the term "selected embodiments" (page 11, lines 11-12) which would signify that only selected embodiments of the prior art fairing could be replaced with a fairing system according to the invention. The application as filed frequently used wording like "certain embodiments", "selected embodiments", et cetera. The qualifiers "certain", "selected", et cetera, did not imply any restrictions, but merely indicated that not all fairing systems in accordance with the invention (e.g. first fittings on new aircraft) were retrofitted on existing aircraft. The term "selected embodiments" clearly referred to the invention, not to the existing aircraft, which would be suitable for retrofit. Consequently, the disclosure on page 11, lines 10-18 in combination with page 1, lines 16-19 of the application as filed provided a clear basis for the wording in the pre-characterizing part of claim 1 and in claim 8, which did not contravene the provisions of Article 123(2) EPC.

Late-filed documents A5-A8 were not admitted by the opposition division in using its discretionary power. All evidence needed to support an assertion of allegedly public prior use had to be filed at least in good time for it to be taken into account by the opposition division. Documents A9-A12 and the associated affidavits and annexes filed with the grounds of appeal could - and should - have been presented in opposition proceedings (Article 12(4) of the Rules of Procedure). If the board were to admit any of these documents, it was requested that the case be remitted to the department of first instance.

Late-filed document E1 was provided in connection with an entirely new inventive step attack on claim 1 and related to alleged public prior use of an aircraft by the opponents themselves, i.e. the principles of proof up to the hilt applied. The website from which the photograph E1 was taken went online 2015, i.e. ten years after the priority date of the patent in suit. No tangible evidence had been presented to identify the date of the photograph or that it was available to the public before the priority date. Moreover, the photograph showed the A380 prototype on the tarmac, probably on Airbus' private grounds. Given that the aircraft shown was a prototype, it was highly unlikely that it was accessible to the general public. It was established case law that use of a product for test purposes was to be treated as confidential. The confidential nature of the A380 prototype was further clear from the fact that its registration number was not to be found on the French Civil Aircraft Register. Consequently, E1 should not be admitted into the appeal proceedings.

As regards interpretation of the term "wide portion" in claim 1, it comprised only a part of the fairing section which had a spanwise width that was either greater than or equal to another spanwise width. Moreover, the opponents used the teaching of the patent in suit to interpret various schematic drawings in A1 and A2, neither of which was concerned with fairing systems or their shape. Schematic drawings which were not supported by any explanatory text could not be considered as disclosure when it came to details (see T 896/92). Dimensions obtained merely by measuring a diagrammatic representation in a document did not form part of any disclosure (T 857/91, T 272/92). Schematic drawings had to be distinguished from scaled construction drawings (T 451/88) and could not be used to derive a ratio between dimensions (T 1664/06). The decisions cited by the opponents related to different sets of circumstances (see T 818/93 - shape, structure and function of stents had already been described in a fair amount of detail; T 748/91 - size ratios were inferred from a schematic drawing under certain circumstances, e.g. the thickness of layers were presented as an essential feature in the description and a ratio for the various thicknesses was eventually derived from the drawings). The actual teaching of A1 and A2 had nothing to do with fairings, which were merely mentioned once, and lacked a clear connection between description and illustration of the fairings.

As regards novelty over A1 or A2, the opponents relied on measurements in the schematic drawing and the derivation of a ratio between two dimensions when establishing that the fairing had a wide portion at least partially aft of the airfoil section. Moreover, they referred to a shaded area they drew in Fig. 1 of A1 or Fig. 6 of A2, which did not constitute a "wide portion" in the sense of features i) and ii) of claim 1, since it covered parts of the fairing section that had a spanwise width that was smaller than a spanwise width at another point of the fairing.

A combination of A1 or A2 with document A3 was based on an incorrect interpretation of the actual teaching of A3 as well as a fair amount of hindsight. The skilled person would not have considered the teachings of A3 (which related to a very specific aerodynamic problem) to improve the aerodynamics of the flap track fairing of A1 or A2. As regards the opponents' view that each fairing design was subject to the same aerodynamics and all fairing designs were interchangeable, its technical expert, Mr. Whitehouse, stated during the oral proceedings before the opposition division (not reproduced in the minutes) that aircraft wing design was "holistic", in the sense that all elements of the design were interconnected, so a change in one design parameter had consequences for the entire design.