dissenting.
Following my review of the evidence presented to the trial court through live testimony and deposition testimony, I am left with the firm conviction that the trial court committed clear error and should be reversed because it analyzed Thompson’s conduct against that of a reasonably prudent pilot under dissimilar circumstances.
The District Court held that VFR conditions constituted the same or similar circumstances to Thompson’s flight. Thompson’s conduct should have been contrasted to that of a reasonably prudent pilot under the circumstances of a cross-country, midwinter, VFR, nightime flight across hazardous terrain and mountains. Additionally, I read the District Court’s finding of no common law negligence as a circular path of reasoning which leads right back to its negligence per se analysis — that a reasonable pilot complies with the Federal Aviation Regulations and since Thompson did not violate any regulations, he was not negligent.
The parties stipulated not only that the ELT was inoperable on the day of the flight, but also to the causal relationship between Thompson embarking on the Mississippi to California flight with an inoperable ELT and Beck’s death. Stipulation No. 55 states “if the batteries in the emergency locator transmitter (ELT) on board N9877K had not been defective, Beck could have been rescued.” 1 The District Court’s opinion reflects that it found Thompson was under no duty to test the ELT,2 request flight following or activate the transponder,3 or file a flight plan.4
A Mixed Question
The Court relies entirely on F.R.Civ.P. 52(a) in reviewing the District Court’s finding of no negligence by Thompson as a finding of fact. However, negligence presents the Court with a mixed question of law and fact. “[Wjhether a defendant owes a plaintiff a legal duty is a question of law while resolution of a defendant’s possible breach of duty is a question of fact.” Welch v. Heat Research Corp., 644 F.2d 487, 489 (5th Cir.1981); Chavez v. *1216Noble Drilling Corp., 567 F.2d 287, 289 (5th Cir.1978).
In Ward v. Hobart Manufacturing Co., 450 F.2d 1176, 1181 n. 15 (5th Cir.1971), which the majority relies on, the Court observed that “the question of the extent of that duty, or the appropriate standard of conduct to be applied seems to be a mixed question of law and fact.” We identified the difficult distinction between law and fact questions in negligence cases in Waterbury v. Byron Jackson, Inc., 576 F.2d 1095, 1097 (5th Cir.1978):
Establishing negligence is ordinarily a mixed question of law and fact. The determination of the standard of care to which the defendant must be held is a question of law, although its legal formulation is guided by proved facts. Deciding whether the defendant adhered to that standard is then a pure question of fact.5
This Court did not ford the Serbonian bog of mixed questions of law and fact6 as it determined that the lower court was clearly erroneous.
One Mile and Clear of Clouds
The error by the District Court was not the factual question of whether Thompson breached the standard of care, but was the legal question of what was the standard of care. The standard of care to which Thompson must be held is that of a reasonably prudent pilot under like circumstances. Both this Court and the District Court erroneously adopted the defendant’s position that the circumstances of this flight are embodied entirely in the fact that it was a VFR flight.
Ms. Wally Funk, the NTSB Air Safety Investigator whose deposition was introduced by the defendant, testified that Visual Flight Rules permit pilots to fly in a seen-and-be-seen environment. Pilots are prohibited from flying VFR any time visibility is less than a prescribed minimum, depending on altitude and airspace restrictions.7 The circumstances of designating a flight as taking place under VFR conditions are predominantly a question of visibility; they do not take into account any other specific circumstances of a particular flight such as the distance of the flight, the terrain over which the flight will cross, or whether the flight is during the day or night.
The Court’s sole reliance on VFR conditions to constitute the same or similar circumstances takes only visibility into consideration and would require the same conduct of a pilot taking a one-hour Saturday afternoon flight around Jackson, Mississippi as it would of a pilot taking a cross-country trip of several thousand miles. The VFR regulations upon which the trial Court and the majority rely constitute a minimum safety regulation for all types of VFR flights and fails to consider the additional precautions that a reasonably prudent pilot would and should take advantage of in a long distance VFR flight under more difficult circumstances. “Unreasonable conduct is not an excuse when one merely complies with minimum regulatory requirements.” Corley v. Gene Allen Air *1217Service, 425 So.2d 781, 784 (La.App.1982) (reversing summary judgment of no negligence in allowing decedents to use plane without an E.L.T. even though not required on that plane by the Federal Aviation Regulations).
The District Court’s error in determining Thompson’s duty under like circumstances is itself sufficient grounds to reverse the District Court’s factual finding of whether Thompson breached his duty to Beck for new findings of fact under the correct legal standard. Pullman-Standard, v. Swint, 456 U.S. 273, 287, 102 S.Ct. 1781, 1789, 72 L.Ed.2d 66, 79 (1982). As we have long held, fact findings made under an erroneous legal principle are not protected by the clearly erroneous standard of F.R.Civ.P. 52(a). I would go farther. Even assuming the legal standard of care is proper, I would still reverse on the grounds that the District Court’s conclusion that Thompson breached no duty by failing to equip his plane with an operable ELT or to request flight following is clearly erroneous under F.R.Civ.P. 52(a).
A Holding Pattern Over Negligence Per Se
I agree with the majority’s determination that there is no negligence per se in this case because of the unusual situation that the Airworthiness Directive suspended 14 C.F.P. § 91.52, which required an operational ELT on Thompson’s plane. If this fatal flight occurred prior to the Airworthiness Directive or after its expiration on March 28, 1980, negligence per se would clearly exist. Compliance with the regulations does not establish reasonable conduct by Thompson. The regulation required ELT’s as a minimum safety regulation. The regulation was not suspended because ELT’s were no longer considered a reasonable safety precaution, but was temporarily suspended to devise proper technical specifications for their batteries. The record reflects that the technical difficulties with the ELT batteries were widely known in the pilot community. Suspending the enforcement of § 91.52 in no way alters the pilots duty to undertake reasonable safety precautions appropriate to the circumstances of the flight on which he/she is about to embark. It is inconceivable to me — and the majority cites no reasons why the trial judge was not forced to the same conclusion — that any pilot could depart Mississippi with the intention of flying to California during the winter months without assertaining whether his ELT was in operating condition, especially in light of the wide publicity within the pilot community of the difficulties with ELT batteries such as those in Thompson’s craft. The existence of the regulation does not eliminate the law’s demand that conduct be reasonable or the obligation of the fact finder to so declare when the facts are so compelling as they are here.
Preflight Testing of the ELT
The majority opinion upholds the District Court’s misplaced emphasis on the cross-examination of the plaintiff’s expert witness — which also emanates from equating all VFR flights as taking place under like circumstances. Plaintiff’s expert witness testified that a reasonably prudent pilot would check the plane’s ELT before embarking on a cross-country flight. The majority states, “the District Court noted that the operation manual for the plane, the applicable federal regulations, and even a book written by the plaintiff’s expert containing preflight and pre-takeoff checklists did not require or recommend preflight testing of the ELT ... and the defendant’s expert witness saw no violation of good safety practices in not testing the ELT prior to takeoff.” However, the Court failed to take into consideration that the operation manual for the plane, the applicable federal regulations, and the book written by the plaintiff’s expert refer to all VFR flights, including the Saturday afternoon flight around Jackson, Mississippi. Evidence was offered at trial that a pilot should undertake additional safety precautions beyond those mínimums for extended flights over dangerous or remote terrain.
The majority requires a pilot to tailor his conduct based solely on visibility and disregards other factors which influence a VFR flight. The defendant’s expert, Glenn *1218Ellis, testified that he tested the ELT on his plane once a week and made a point of always testing it before any flight which would take him over the Atlantic Ocean outside of gliding distance to shore so that he could “get picked up out of a life vest or a life jacket if [he] went into the sea.” I cannot read this testimony in such a way that it would permit the trial Court to plausibly conclude that Thompson acted in a reasonably prudent manner in not testing his ELT prior to undertaking a flight from Mississippi to California in the middle of winter. Although Ellis testified that ELT’s are normally tested only at the annual inspection and that he saw no failure of good practices among pilots in failing to conduct a test or inspection of the ELT before taking off on a cross-country flight, Ellis summed up the entire tenor of his testimony by his statement that he knew reasonably prudent pilots that did not take advantage of readily accessible safety precautions and he also knew of reasonably prudent pilots who did. He concluded that more reasonably prudent pilots did not take advantage of these precautions than the amount of reasonably prudent pilots who did.
Reasonable conduct under the same or similar circumstances is not measured by the conduct of the majority of people in the same position as the plaintiff. The fact that the majority of pilots act in an unreasonable manner does not make their conduct reasonable8 nor must the conduct of any one pilot be used as the standard of reasonableness.9 Ellis testified about the conduct of individual pilots and not of the mythical man of legal fiction — the reasonably prudent person. This is a critical error of law which deprives his findings of any legal vitality.
Two precautions which were readily available to Thompson, and for which a causal relationship to Beck’s demise exists,10 are the ELT and flight following. The defendant’s expert testified that the first five minutes of each hour are designated as a testing period for ELT’s.11 The pilot can accomplish this by turning on the ELT and tuning his radio to the emergency frequency to listen for the ELT’s transmission. On a cost benefit analysis, when one considers the cost of testing the ELT prior to a difficult cross-country flight against the benefits, it can hardly be said that the trial Judge could conclude that a reasonable person would not take advantage of this extra insurance of being rescued in the case of a crash.
The other safety feature which Thompson failed to utilize was a transponder with flight following.12 Flight following of VFR flights, without question, is lower priority traffic for air traffic controllers than IFR flights. Thus, a pilot would have reason to believe that the air traffic controllers might not be able to dedicate sufficient time to provide flight following during high traffic times. The evidence demonstrated the traffic was, and usually is, extremely light near Mount Graham at 10:00 p.m. In fact, radar printouts showed two VFR flights were being provided with flight following in that sector at the time Thompson attempted his flight, one of them was fol*1219lowed until it landed at Stafford’s airport near the base of Mount Graham.
Although, on cross-examination, the plaintiff’s expert agreed with the defendant’s expert that the great majority of VFR flights do not use either flight plans or flight following service. He explained this by stating “[w]hen we’re saying the great majority of these flights, we’re talking about an awful lot of flights that are five, ten, fifteen minutes in length over inhabited areas during the daytime, non-mountainous terrain____ [But in the case of ljengthy VFR flights, flights through terminal areas, flights over mountainous terrain at night and midwinter: I would say there’s a great majority of those flights that use the flight following service.” The NTSB Safety Inspector testified that “[a] prudent pilot would use [a transponder]. It’s a form of insurance.” This testimony amplifies the trial judge’s error in law and fact of failing to distinguish between circumstances of VFR flights other than visibility.
Conceding that in our appellate role the majority opinion properly states that it might disagree with the District Court’s view of the evidence in this instance, but cannot say it is clearly erroneous, I do not have the same difficulty.
The clearly erroneous standard of F.R. Civ.P. 52(a) extends great deference to the District Court’s findings of fact. It is not an insurmountable deference, however. If the appellate court reviews the evidence at trial and determines that there are two plausible conclusions which one could reach from that evidence, it must affirm the District Court’s finding of fact. Anderson v. Bessemer City, 470 U.S. 564, 105 S.Ct. 1504, 84 L.Ed.2d 518 (1985). On the other hand, equally well established, and in no way imperiled by Anderson, is the Supreme Court’s declaration that even if the appellate court finds sufficient evidence to support the district court’s finding of fact, but on the entire evidence is left with the definite and firm conviction that a mistake has been committed, the district court’s finding of fact is clearly erroneous and must be reversed. United States v. U.S. Gypsum Co., 333 U.S. 364, 68 S.Ct. 525, 92 L.Ed. 746 (1948). See also Lidy v. Film Transit, Inc., 796 F.2d 103, 105 (5th Cir. 1986); Noritake Co. v. M/V Hellenic Champion, 627 F.2d 724, 728 (5th Cir. 1980).
My meticulous review of the trial transcript, including the deposition testimony before the trial Court, reveals evidence which supports the District Court’s conclusion only if one equates a fifteen-minute VFR flight around Jackson, Mississippi with a cross-country midwinter flight from Mississippi to California at night as constituting the same or similar circumstances. I am of the very definite opinion that this is not only an improper standard by which to analyze the conduct of a reasonably prudent pilot in this case, but this error of law denies the protection of F.R.Civ.P. 52(a) to the fact findings induced by it.
The trial Court was wrong in entering judgment for the Defendant and this Court is wrong in not reversing either for rendition or new trial.
I therefore respectfully dissent.
. At trial and in post-trial briefs the parties disputed whether the term "rescued” in this stipulation means that she would have survived or merely that a rescue team would have reached the site earlier. As Judge Lee stated from the bench, "a stipulation ... shouldn’t be something that I’ve got to start interpreting to decide what you mean by it, something that says one thing and [means] something else that appears to be contradictory. That’s just not worth a hoot as a stipulation as far as the court is concerned.”
I also agree with Judge Lee’s further statements that there can only be one interpretation to Stipulation 55 and that is one of survivability.
. Regarding a duty to check the ELT, the District Court held:
Mere compliance with applicable regulations, however, may not alone absolve Thompson of liability. Plaintiff contends, supported by her expert witness, ... that a reasonably prudent pilot would check the plane’s ELT prior to flight. Such a timely check would have disclosed the faulty ELT. The operation guide for the plane, applicable federal regulations, and even [plaintiffs expert’s] book ... do not require or recommend testing of the ELT. Accordingly, this court is of the opinion that Thompson did not breach a duty in failing to test the ELT or in having an inoperable ELT on board.
Beck v. Thompson, C.A. No. J83-0163(L), slip op. at 8 (S.D.Miss. Dec. 13, 1985).
Although the court uses "breach of duty” language, it is clear from the context that in holding that Thompson breached no duty by not testing the ELT or having an operable ELT on board, he concluded Thompson had no duty to test his ELT or have an operable ELT on board.
. Regarding the use of a transponder and flight following the District Court held:
[T]his court is of the opinion that Thompson was not negligent in failing to request flight following or in failing to activate the transponder in that he had no duty to do so.
Id. at 10.
. Similarly, the District Court held that "Thompson had no duty to file a flight plan under the circumstances.” Id.
. In reviewing negligence questions, the Ninth Circuit abides by these same standards — which differs from the dicta in Ward. "The existence and extent of a duty of care are questions of law but whether such a duty has been breached and whether proximate cause exists are questions for the fact finder, whose determination is binding on appeal unless clearly erroneous.” Armstrong v. United States, 756 F.2d 1407 (9th Cir. 1985) (emphasis added), citing Foss v. United States, 623 F.2d 104 (9th Cir.1980).
. Today we cannot avoid “the Serbonian bog which appears to encircle ... a mixed question of fact and law.” Junior v. Texaco, Inc., 688 F.2d 377, 379 (5th Cir. 1982); J. Milton, Paradise Lost 592 (1667) (“A gulf profound as that Serbonian bog Betwixt Damiata and Mount Casius/old where Armies whole have sunk”).
. 14 C.F.R. § 91.105 provides that “no person may operate an aircraft when the flight visibility is less, or the distance from clouds is less, than that prescribed for the corresponding altitude in the following table____” The table requires flights such as Thompson’s which are more than 1,200 feet above the surface, but less than 10,000 feet mean sea level and outside controlled airspace, to have one mile visibility and maintain a distance from clouds of 500 feet below, 1,000 feet above, and 2,000 feet horizontal. Section 91.107(d) requires three miles visibility to take off or land an aircraft under VFR conditions.
. "What ought to be done is fixed by a standard of reasonable prudence, whether it usually is complied with or not.” Texas & Pacific Ry. Co. v. Behymer, 189 U.S. 468, 470, 23 S.Ct. 622, 623, 47 L.Ed. 905, 906 (1903). See also B & B Insulation, Inc. v. Occupational Safety and Health Review Commission, 583 F.2d 1364 (5th Cir.1978).
. The Reasonably Prudent Person is "a personification of a community ideal of reasonable behavior, determined by the jury's social judgment” and not by the conduct of any one individual. Prosser & Keeton on Torts § 32 at 175 (5th ed. 1984). Yet evidence of similarly situated individuals' conduct may be probative. B & B Insulation, 583 F.2d at 1370.
. See supra note 1.
. The parties stipulated that Thompson departed Jackson, Mississippi at 12:15 p.m. He surely would have been in his airplane during the ELT testing period.
. Thompson’s plane was equipped with a transponder that merely needed to be turned to the on position followed by a radio call requesting flight following. In exchange for this minor effort, the air traffic controller would have kept Thompson up-to-date on any weather systems in the area and any obstacles such as other planes or mountainous terrain in his path.