Martin v. United Aircraft Corp.

32 F. Supp. 367, 45 U.S.P.Q. (BNA) 204, 1940 U.S. Dist. LEXIS 3366
CourtDistrict Court, D. Delaware
DecidedApril 5, 1940
DocketNo. 1164
StatusPublished
Cited by3 cases

This text of 32 F. Supp. 367 (Martin v. United Aircraft Corp.) is published on Counsel Stack Legal Research, covering District Court, D. Delaware primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Martin v. United Aircraft Corp., 32 F. Supp. 367, 45 U.S.P.Q. (BNA) 204, 1940 U.S. Dist. LEXIS 3366 (D. Del. 1940).

Opinion

NIELDS, District Judge.

This is a civil action brought in March, 1936, for alleged infringement of three patents issued to plaintiff. The defenses are (1) invalidity by reason of anticipation and lack of invention, and (2) nouinfringement.

Each of the patents has to do with retractable landing gear for aircraft. They are:

No. 1,306,768 granted June 17, 1919 on an application filed June 8, 1916. The patent expired three months after this action was brought. The claims in issue are Nos. 1, 2, 3, 5, 17, 18, and 19.

No. 1,418,008 granted May 30, 1922 on an application filed November 14, 1918. The patent expired shortly after the conclusion of the trial of this action. The claims in issue are Nos. 2, 4, 5, 16, 17, 21, 35, 36, 40, 41, and 42.

No. 1,431,017 granted October 3, 1922 on an application filed March 5, 1921. This patent expired October 3, 1939. The claims in issue are Nos. 16, 17, 18, 19, 21, 24, 29, 30, 32, 34, 35, 37, 41, 43, and 44. .

A retractable landing gear is simply a device for pulling up the wheels, pontoons, skids, or the like, of an airplane while it is in flight, and letting them down when the airplane is ready to alight. The purpose of pulling up the wheels may be to lessen air resistance or simply to get them out of the way of the water.

Both amphibian and land planes with retractable landing gear go back to the [368]*368earliest days of the airplane art. As stated in plaintiffs brief, “The idea simply of withdrawing or retracting the chassis frame members within the fuselage or body of an airplane was not new with the plaintiff.” Plaintiff’s contention is that he was the first to perceive that holes, recesses, or slots in the outer skin of an airplane caused as much disturbance to the flow of the layer of air adjacent the skin of the plane, termed the “boundary layer air flow,” as was caused by projections outside the skin of the airplane. Martin sought not only to retract the alighting devices close up against the body or wings, as many had done in the prior art, but to so retract them as to disturb the boundary layer air flow as little as possible. In the specifications of the first patent he states: “The construction also provides means for completely housing the device when the machine is in flight, and when extended of closing the housings in such a' manner as to present minimum wind resistance and not disturb the passage of air along the stream line of the fuselage when the recesses are not occupied by the alighting device.”

The evidence shows no use or recognition by the art of any of the patents in suit. No commercial machine has ever been built thereunder. No one has taken a license under any of the patents. The plaintiff delayed bringing suit until the patents were about to expire. Plaintiff was present in court throughout the trial and did not testify as a witness. His only witness was an expert who had never seen defendants’ structures.

The bill, verified by plaintiff, alleges that the patents are of great utility and value to the plaintiff and benefit to the public. That at all times since making the alleged inventions plaintiff has maintained and still maintains a plant, factory and equipment for manufacturing the alleged inventions “to fill the demand therefor”, but has been prevented from supplying the demand by the alleged infringement. No attempt was made to adduce any evidence to support these allegations.

Under the above circumstances the claims must be limited to the specific mechanical constructions that the patents actually disclose.

Defendants are all Delaware corporations. United Aircraft Corporation owns all the stock of the other two defendants. It manufactures the Sikorsky airplanes.

The accused machines are four Sikorsky models known as S-38, S-39, S-40 and S-43; and one Boeing model known as 247. Plaintiff relies exclusively upon defendants’ answers to plaintiff’s interrogatories as showing the accused structures. With the exception of model S-40, all the Sikorsky planes are amphibian, i. e., capable of taking off and alighting on either land or water. Only three machines like model S-40 were ever built, and only the first of these had any landing wheels. After testing the first model, the wheels and landing gear were removed and the machine was used as a seaplane. The other two were built and operated as seaplanes. In short; the three S-40 models were flying boats.

The accused Boeing is a land plane exclusively. Its wheels are simply pulled up while flying and let down for alighting. It was bought by defendants from another manufacturer for the use of the executives of defendants.

As to the first Martin patent, both front wheels and tail wheel of the S-43 are charged to infringe claims 3, 17, 18, and 19. These four claims were all held invalid by the Court of Claims. Martin v. United States, 37 U.S.P.Q. 55, 57.

In Martin’s suit against the government on the second patent, the Commissioner of the Court of Claims filed his report and recommended that all of the claims there in suit (1, 3, 5, 8, 9, 10, 15, 16, 17, 21, 35, 37, and 42) be held invalid.

Plaintiff’s Patents.

The first patent relates to means for retracting and protracting la'nding gear for aircraft. More particularly, it discloses a swinging frame, quadrilateral in form, with a single diagonal, and arranged transversely the airplane. The frame is pivoted at its two upper corners and has a wheel at each lower corner. The frame can be swung up rearwardly by hand cranking. When retracted the frame members fit into slots in the bottom of the airplane. The wheels may go wholly outside the airplane body or partly inside. When protracted the slots in the bottom of the airplane are closed by spring-pressed plates, housed wholly within each slot. When retracted the slots receive and are completely filled and closed by the frame members. The frame members are specially shaped and fit into the slots. When protracted the frame must be latched in down position before the airplane can land on it; otherwise it would simply dangle in the air. The airplanp [369]*369can land only with its wheels fully extended.

This first patent lacks utility. It discloses a frame, quadrilateral in form, which the patent later states is unnecessary. It is inoperative. It describes a construction dangerous to life. If the wheels be retracted while the machine is in the air, it would be practically impossible for the pilot to put them down into position for landing while attending to his other duties. These other duties include operation of the joystick to control the plane both laterally and longitudinally, steering, and management of the throttle.

The second patent discloses landing gear consisting of a frame supporting landing wheels in many respects similar to that of the first patent. It makes provision for a wheelbase wider than the body of the airplane whereby the frame may be housed partially in the body of the airplane and partially in the wing structures. The wheels go through holes in the wing where they may be covered by housing on top of the wing. The same form of quadrilateral swinging frame as shown in the first patent is retained but the single diagonal is abandoned and two intersecting diagonals are used. A worm gear of “any well-known form” of the irreversible variety holds the swinging frame in any position to which it is adjusted. The construction is said to be such that the airplane can land when the wheels are “in any projected position”.

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Bluebook (online)
32 F. Supp. 367, 45 U.S.P.Q. (BNA) 204, 1940 U.S. Dist. LEXIS 3366, Counsel Stack Legal Research, https://law.counselstack.com/opinion/martin-v-united-aircraft-corp-ded-1940.