Myers v. Cessna Aircraft Corp.

• Decision Date: 09 July 1976
• Citation: 553 P.2d 355,275 Or. 501
• Parties: Mary M. MYERS, Administratrix of the Estate of Clifford E. Myers, Deceased, for the benefit of Mary M. Myers, surviving wife of the Deceased, et al., Respondent, v. CESSNA AIRCRAFT CORPORATION, a Kansas Corporation, Defendant, Robertson Aircraft Corporation, a Washington Corporation, Appellant.
• Court: Oregon Supreme Court

Page 355

553 P.2d 355

275 Or. 501

Mary M. MYERS, Administratrix of the Estate of Clifford E.

Myers, Deceased, for the benefit of Mary M. Myers, surviving wife of the Deceased, et al., Respondent, v. CESSNA AIRCRAFT CORPORATION, a Kansas Corporation, Defendant, Robertson Aircraft Corporation, a Washington Corporation, Appellant.

Supreme Court of Oregon.

Argued and Submitted Dec. 1, 1975.

Decided July 9, 1976.

[275 Or. 502-E] Kenneth E. Roberts, Portland, argued the cause for appellant. With him on the briefs were Ridgway K. Foley, Jr., and Souther, Spaulding, Kinsey, Williamson & Schwabe, Portland; and Kenneth C. Miller, of Lord, Bissell & Brook, Chicago, Ill.

Robert B. Hopkins, Portland, and Martin Schedler, [275 Or. 502-F] Portland, argued the cause for respondent. With them on the brief were David W. Harper, and Keane, Haessler, Harper, Pearlman & Copeland, Portland.

Before O'CONNELL*, C.J., and McALLISTER, DENECKE**, HOLMAN, HOWELL and BRYSON, JJ.

HOWELL, Justice.

This is a wrongful death action arising out of the crash of a light airplane in Birtish Columbia during a flight from Hillsboro, Oregon to Kimberley-Cranbrook, B.C. in September, 1970. The plaintiff, Mary Myers, is the administratrix of the estate of her husband, Clifford, a passenger who died in the crash. Defendant Cessna Aircraft Corporation is the manufacturer of the plane, and defendant Robertson Aircraft Corporation made some modifications on the plane prior to the flight to British Columbia. Plaintiff's complaint alleged causes of action for negligence and strict liability against each defendant. Following a jury trial, a verdict was returned against Robertson alone. Robertson appeals from the judgment entered on the jury's verdict. ¹

The airplane involved in this crash was a Cessna T337B. Robertson performed a short take-off and landing (STOL) modification on the plane at its Washington plant in 1969. A STOL modification is designed to permit better slow flight characteristics and shorter take-offs and landings. It involves modifications of the wing design and other component parts. One of these modified components, the pitot tube, is the center of the controversy in this appeal.

The pitot tube is an L-shaped metal tube which hangs below the left wing of the plane. Its function is to measure the speed of the aircraft through the air mass. This speed is registered on the 'air speed indicator' which compares the pressure of the air mass impacting on the pitot tube with the pressure of undisturbed air at the same altitude, as measured by the 'static source pressure system.' The pitot tube is equipped with a heating element designed to prevent ice formation in the pitot tube in the event that icing conditions are inadvertently encountered during flight. If ice were to form in the pitot tube, the reading on the air speed indicator would be affected and that instrument would no longer be reliable.

When Robertson performed its STOL modification on the Cessna aircraft, the change in wing shape altered the air flow impacting on the pitot tube, and this affected the accuracy of the air speed indicator. In order to overcome this problem, Robertson extended the total length of the tube more than six inches, approximately doubling the length of the original Cessna pitot tube. Despite this modification, Robertson utilized the original heating element which had been developed by Cessna for use in its own shorter tube.

Plaintiff's complaint alleges that Robertson was negligent (a) in failing to properly manufacture and design the modified pitot tube; (b) in failing to test the modified pitot tube to see if it would withstand icing conditions; (c) in failing to supply sufficient heat to the modified pitot tube; and (d) in failing to warn of the above failures. The complaint also alleges that the modified aircraft was dangerous and defective because of Robertson's design and testing failures and because of Robertson's failure to warn of the dangers involved. The complaint further alleges that as a result of Robertson's negligence the modified airplane crashed and the decedent was killed.

Essentially, plaintiff's theory was that some time after crossing the Canadian border under instrument flight rules, the plane encountered severe icing conditions; that the pitot tube iced up, causing the air speed indicator to fail; that other instruments for which Robertson was not responsible also failed; that the pilot became disoriented due to instrument failure; and that the plane lost altitude until it finally broke out of the clouds just before the impact. Robertson's theory was that the accident was due solely to pilot error.

Since everyone in the plane was killed, there were no witnesses to the crash and most of the evidence produced at trial was necessarily circumstantial. The evidence produced by both sides was voluminous and often in conflict. However, since the jury returned a verdict in favor of the plaintiff and against defendant Robertson, on appeal the evidence must be considered in the light most favorable to plaintiff.

Plaintiff produced expert meteorological testimony indicating that the plane encountered a cold front some time after crossing the border and was thereafter flying through heavy clouds, continuous rain, moderate to severe turbulence, freezing temperatures and increasingly severe icing conditions. Another of plaintiff's experts testified that his laboratory tests showed that Robertson's modified pitot tube iced up under similar conditions and that the original Cessna tube did not. There was also testimony that when flying from one air mass into another, such as through a frontal system containing a large temperature differential, icing conditions could change suddenly, and the pitot tube could freeze up rapidly.

Plaintiff's evidence also indicated that the air speed indicator is a primary flight instrument and that it gives the pilot one of his main indications as to what the plane is doing. There was testimony that its use becomes critical under conditions in which the plane is picking up excessive ice over a short period of time while also encountering turbulence. There was also other testimony from which the jury could conclude that when the air speed indicator was lost under these conditions, it became dangerous to continue flying through such weather since the aircraft might stall.

There was further testimony that in order to avoid this danger a pilot could either change altitude by ascending or descending, or turn back or, if the weather at a terminal close ahead was known to be clear, the pilot could descend toward that area. One of plaintiff's witnesses testified that when he was flying a similar Robertson-modified Cessna in icing conditions and turbulence, he lost his air speed indicator and was forced to make a blind emergency descent to 500 feet over the ocean where he knew the air was warmer. Finally, plaintiff's expert aircraft accident reconstruction expert testified that in his opinion the crash was caused by instrument failure due to the freezing of the Robertson pitot tube and the Cessna static pressure system while the plane was encountering moderate to severe icing conditions and turbulence.

Transcripts of the plane's radio communications reveal that the pilot did not report any encounter with icing conditions and did not request permission to alter his flight plan. However, there was also testimony which indicated that in an emergency the pilot would first have to deal with the problem itself and would later notify the air controller when it became practical to do so.

On appeal, Robertson makes over 40 assignments and subassignments of error. Although we have considered all of these assignments, this opinion will review in detail only those assignments of error which merit any extended analysis. ²

In its first assignment of error, Robertson contends that '(t)he circuit court erred in refusing to rule as a matter of law that plaintiff failed to prove negligence or strict liability against Robertson, and in admitting improper opinion evidence in that regard.' This assignment of error is broken down into 16 subassignments of error. The first six of these subassignments relate to various actions of the trial court 'in refusing to rule as a matter of law that plaintiff failed to prove negligence or strict liability against Robertson.' ³ The next ten subassignments of error relate to the introduction of certain evidence over Robertson's objection. ⁴ Essentially, Robertson's contention is that some of plaintiff's opinion evidence should not have been admitted and that, without this evidence, plaintiff's case was not sufficient to go to the jury.

Plaintiff presented expert meteorological evidence of the existence of icing conditions in the area through which the plane was flying. Plaintiff's experts were experienced in collecting, charting and interpreting weather data for aviation operations. One of these two experts had 14 years of experience interpreting weather data in the Kimberley-Cranbrook area where the crash occurred. In the past, both this court and others have recognized the propriety of utilizing meteorological data and the testimony of experts based thereon to assist the jury in determining the applicable weather conditions and the effects of those conditions. See, e.g., Stone v. Beneficial Standard Life, 272 Or. 129, 535 P.2d 764 (1975); Gillespie Land and Irr. Co. v. Gonzalez, 93 Ariz. 152, 379 P.2d 135 (1963); Potter v. Schleck, 9 Wis.2d 12, 100 N.W.2d 559 (1960).

All three meteorologists who testified in this case, including one presented by defendant Cessna, indicated that the existence of icing conditions was probable in the area through which the plane was flying shortly before the crash. The record is clear that the opinions of all three meteorologists were based upon official scientific weather observations. Plaintiff's experts testified that the plane would have...