Opinion ID: 1146481
Heading Depth: 1
Heading Rank: 4

Heading: The Critical Question

Text: The important question for us is not where the magnetos were set February 20, 1962, when the engine was checked by the manufacturer, but where were they on September 3, 1963, when the motor failed? Unfortunately, no evidence was offered by the claimants to show what the magneto settings were at the time of the crash, or at any time between February 20, 1962, and September 3, 1963. One of Continental's engineers testified that, based on his experience with the engine model here involved, the magnetos would have advanced from 24° to about 34° at the time of crash, if not checked in the meantime. In the light of the evidence we have described, it is doubtful if it can be inferred that magnetos were still at 24° at the time of the accident. If Wyoming Air Service had bumped the magnetos or changed them at all, then Continental could not be held responsible. On the other hand, if Wyoming Air Service failed to change from 24° down to 20° in accordance with the bulletin instructions, and if it failed to check the magneto settings on the 100-hour inspections, Continental's liability would be doubtful. Johnson, of Wyoming Air Service, admits his company had all of the applicable service bulletins issued by Continental prior to any of the 100-hour inspections. Also, it is undisputed the engine with which we are concerned had logged 390 hours at the time of the crash. The record shows without contradiction that FAA regulations require a 100-hour inspection at the end of each 100 hours of service. The 100-hour inspection, among other things, includes a check of the magneto settings and a compression test. Johnson's testimony was confusing and contradictory as to whether he had checked magneto settings or made compression tests at any of the 100-hour inspections made by him. As previously indicated, counsel for Joly contends he did none of these things, and the jury was entitled to believe, and apparently did believe, such accusations against Johnson were for the most part true. Here again, we quote arguments made by Joly's attorney in his brief: It was admitted and uncontested by defendant Wyoming Air Service that they had all the applicable service bulletins issued by Continental Motors Corporation prior to the time of the first 100-hour inspection made on the aircraft, and that such inspections were made on the 11th day of November, 1962; the 23rd day of February, 1963 and the 15th day of May, 1963. That the mags were never changed is in conformity with Johnson's statement to the FAA in his own handwriting (which was given before the filing of the lawsuit), and with the assertion of his assistant, Maxson, who states that the mags were `never messed with.' The inconsistency of Johnson's statements during the trial as to when, if ever, the mags were changed speaks for itself on the question of credibility. The two Continental bulletins we have made particular reference to and quoted from (dated December 10, 1959 and February 7, 1962) were offered in evidence on behalf of Joly and Darr. In addition to these bulletins, we have referred to considerable evidence offered on behalf of Continental, which was not contradicted or disputed in any way. However, realizing the jury has great latitude in accepting or rejecting testimony of experts and other witnesses, we turn back again to claimants' burden of proof. Was it proved by substantial evidence that the particular engine we are concerned with would destroy in 390 hours on account of having the magnetos set at 24° B.T.C. instead of at 20°? That seems to be the ultimate and critical question. In dealing with this question, we must keep in mind that no inference of negligence can be based on mere surmise, guess, speculation or probability. Tower v. Horn, Wyo., 400 P.2d 146, 147; Gerdom v. Gerdom, Wyo., 444 P.2d 34, 37. In examining the evidence presented by Joly and Darr, we find their witnesses testified about airplanes in general and not about the particular type with which we are concerned. Moreover, there was no attempt to take into consideration the magneto setting approved by the FAA and the one the engine was designed for at the time of its manufacture, or the actual optimum setting for the particular engine. In general, the witnesses for claimants expressed only probabilities and generalities when testifying about the effect of advanced magneto settings. For example, a mechanic from Denver Beechcraft thought, if a plane were to operate over 300 hours with magneto settings 4° higher than specified by the manufacturer, there would be a probability of it reducing the life of the engine and it would be probable the engine would fail. Also, despite claimants' efforts to discredit the testimony of Johnson, claimants seek to rely on him for an expression of probability in the following testimony: Q And wouldn't you also say as an expert mechanic and based upon your opinion that it's probable that an aircraft engine would fail in two to three hundred hours with its mag setting as much as four degrees higher than the setting specified by the manufacturer? A I'd say yes, it's possible. Q And wouldn't you say that it is a probability? A Yes. On the matter of magneto settings, Joly and Darr also seek to find some comfort in the testimony of two of Continental's engineers. Counsel try to support the proposition that the engine would fail with an advance of only four degrees (from 20° to 24°). They say of these witnesses, they thought that was possible. The record does not, however, bear out what counsel claim. The witnesses did not so testify. One engineer did answer a hypothetical question about a magneto setting of 13° above the original 24° to the effect that in such a case engine failure might be expected. Even at best, counsel are still talking only about what is possible.