VAN DUSEN, Circuit Judge:
This is a case, arising under Federal diversity jurisdiction, where an airplane in which the plaintiffs' decedents*fn1 were passengers crashed and all persons were killed.
On December 8, 1963, at 1:00 P.M., Mark Riguette, the pilot of a single engine air charter plane, owned and operated by the defendants, took off from Peterson Field*fn2 to pick up two passengers at Washington, D.C., National Airport. While en route to Washington, he received a weather briefing from the Phillipsburg flight service station*fn3 indicating that a cold front was moving from Eastern Ohio into Western Pennsylvania. At approximately 2:55 P.M., the plane landed at the Washington National Airport, picked up the passengers, and departed for University Park Airport at State College, Pennsylvania. Although the pilot obtained no weather briefing before leaving Washington, he contacted the pilot-to-forecaster service at 3:12 P.M. while over Frederick, Maryland. The service informed him that there was an indefinite ceiling of 1200 feet at Phillipsburg, with visibility of two miles; that there would be moderate icing and turbo-severe turbulence along his route; and that the front would lower the ceiling to 1000 feet and visibility to one or 1 1/2 miles. The forecasting service did not expect the front to reach Phillipsburg for another two or three hours. At 3:17 P.M., shortly after the communications between Frederick and the pilot were concluded, the forecasting service altered its prediction. According to the new forecast, it was expected that the ceiling would drop to 500 feet and visibility would be limited to one-half mile. The revised forecast was repeated by all weather stations along Riguette's route at 3:45 P.M. and was available to him upon request at any time after 3:17 P.M.
The pilot did not land at University Park as planned, but radioed Peterson Field at 3:50 P.M., reported that he was over Port Matilda,*fn4 and advised that he would land at Peterson. By the individual co-defendant's own admission (he was the only witness called by defendants), the ceiling at Peterson was then only 800 to 1000 feet. At 3:59 P.M., the plane crashed into Bald Eagle Mountain*fn5 while in a level flight cruise condition, heading due west during a heavy snowstorm. The pilot and both passengers were killed in the crash.
Altoona Aviation Corporation appeals from a judgment for plaintiffs entered on December 7, 1967, after judgment n.o.v. had been entered for plaintiffs on the liability issues following a jury verdict at the first trial in defendants' favor, which was followed by a second jury trial limited to the damage issues.*fn6
Since substantially all of the plaintiff's evidence was adduced by testimony, the appellant claims that the District Court was precluded from entering a judgment n.o.v. by the Pennsylvania oral evidence rule,*fn7 which provides, according to appellant, that it is the province of the jury in trespass cases, where oral testimony is concerned, to pass upon the credibility of witnesses, even though uncontradicted by defendant's witnesses or even though defendant introduces no testimony at all. We find it unnecessary to determine the extent of this Pennsylvania rule or its application to the situation presented in the case now before the court.
Irrespective of the applicability of the above Pennsylvania oral evidence rule, which cannot be determined with certainty by a federal court in view of the language in the Pennsylvania cases, the federal decisions make clear that, insofar as this rule attempts to define when the jury must decide, as its function, whether the particular elements of liability exist, it would be operating in a field reserved for federal law. See Lind v. Schenley Industries, Inc., 278 F.2d 79, 84 (3rd Cir.), cert. denied, 364 U.S. 835, 5 L. Ed. 2d 60, 81 S. Ct. 58 (1960); Boeing Company v. Shipman, 389 F.2d 507, 510-13 (5th Cir. 1968), and cases there cited. Where the party having the burden of proof produces evidence which establishes the facts in his favor so clearly that reasonable men could have no doubt, he is entitled to a verdict directed in his favor. Byrd v. Blue Ridge Cooperative, 356 U.S. 525, 2 L. Ed. 2d 953, 78 S. Ct. 893 (1958); Herron v. Southern Pacific Company, 283 U.S. 91, 75 L. Ed. 857, 51 S. Ct. 383 (1931).*fn8 Therefore, the standard against which judgment n.o.v. must be tested is the standard contained in Mihalchak v. American Dredging Company, 266 F.2d 875, 877 (3rd Cir. 1959), where we said:
"The question raised by plaintiff's motion . . . then, is whether he had so well succeeded in carrying his burden of producing evidence that he was entitled to a verdict in his favor as a matter of law.
"The propriety of directing a verdict in appropriate situations in favor of the party imposed initially with the risk of non-production of evidence seems to be well settled. Yet though a motion . . . in favor of the proponent of an issue is cast in the same form as when made by the defending party, it requires the judge to test the body of evidence not for its insufficiency to support a finding, but rather for its overwhelming effect. He must be able to say not only that there is sufficient evidence to support the finding, even though other evidence could support as well a contrary finding, but additionally that there is insufficient evidence for permitting any different finding. The ultimate conclusion that there is no genuine issue of fact depends not on a failure to prove at least enough so that the controverted fact can be inferred, but rather depends on making impossible any other equally strong inferences once the fact in issue is at least inferable."
On the basis of that standard, we hold that the trial court committed no error in granting judgment n.o.v., since, on this record, the pilot of the ill-fated plane was negligent as a matter of law.
The substantive law of Pennsylvania, which we are bound to follow,*fn9 holds that a common carrier owes its passengers the duty of exercising the highest degree of care. Griffith v. United Air Lines, 416 Pa. 1, 203 A.2d 796 (1964). This duty is violated by negligence per se which arises from the violation of a governmental safety regulation. Jinks v. Currie, 324 Pa. 532, 188 A. 356 (1936); Gaskill v. Melella, 144 Pa. Super. 78, 18 A.2d 455 (1941). As the pilot of a single engine aircraft, Riguette was required to fly according to FAA visual flight regulations (VFR). Reasonable men could come to no other conclusion on this record but that certain visual flight regulations were violated. The appellant is, of course, liable for any injuries which were proximately caused by this negligence per se. Ennis v. Atkin, 354 Pa. 165, 47 A. 2d 217 (1946).*fn10 The following uncontroverted facts show violation of at least these enumerated regulations:
(1) The plane was in a level flight cruise condition at the time it struck the mountain. The only reasonable inferences which may be drawn therefrom are that (a) the pilot was not watching where he was going, or (b) he could not see where he was going, or (c) he was simply flying the plane below VFR minimum altitude requirements.*fn11 Any one of these inferences can lead only to the conclusion that the pilot was violating VFR safety requirements, the design of which is to prevent air disasters. When flying VFR, the pilot may not rely on instruments, he must watch where he is going; if he fails to watch, he is negligent per se, and, similarly, if weather conditions obstruct his view, he should leave the area and proceed to a location where he can see.*fn12
(2) By flying the aircraft into an area where the ceiling was below 1000 feet and visibility was less than one mile,*fn13 the pilot violated minimum weather ...