From the judgment entered, it appears that the court found no evidence of actionable negligence on the part of the defendant and, in addition, found that the plaintiff’s own negligence was the cause of the accident.
“The hiring or rental of aircraft constitutes a bailment contract . . . . ” 2A C.J.S., Aeronautics and Aerospace, § 100. “While one who rents or hires an airplane from another is not, as bailee, an insurer thereof, he must exercise towards the aircraft the ordinary degree of care required by a reasonable person in the light of all the circumstances present at the time. He is bound to exercise elementary principles of safe flying .... (footnotes omitted)” 2A C.J.S., id., § 105, p. 243; accord, Jackson v. Stancil, 253 N.C. 291, 116 S.E. 2d 817 (1960). “[R]es ipsa loquitur does not apply, ‘it being common knowledge that aero-planes .do fall without fault of the pilot.’ Furthermore, there must be a causal connection between the negligence complained of and the injury inflicted. Smith v. Whitley, 223 N.C. 534, 27 S.E. 2d 442.” Jackson v. Stancil, supra at 297.
 Plaintiff introduced evidence as to the customary and proper procedure for approaching and landing at Durham Sky-park in a Cessna 172. Plaintiff also introduced evidence to the effect that' defendant’s approach and landing did not conform to the procedure outlined by the plaintiff’s witness. Defendant was too high, not far enough out, traveling too fast, and had out insufficient flaps. In addition the defendant’s “S” turns were shallow when the customary procedure would call for deep banking “S” turns to slow the plane. Instead of remaining aligned with the runway, defendant drifted off the landing path. He then landed at an angle, at a speed above the optimum for a Cessna 172, and at too flat an attitude when the customary procedure would be to pull the nose up.
*112While evidence of custom or general practice or optimum procedure is not conclusive on the necessary standard of care, deviation from such standards is evidence of negligence to be used by the jury in determining what the ordinary degree of care required of a reasonable person would be in the same circumstances. See generally 65A C.J.S., Negligence, § 232. When the evidence is considered in the light most favorable to the plaintiff, it Will permit but not compel the jury to find that the defendant was negligent in approaching the Durham Skypark and landing the aircraft and that such negligence was a proximate cause of the damage complained of.
With respect to the negligence of the plaintiff, “ a directed verdict for the defendant ... on the ground of contributory negligence should be granted when, and only when, the evidence, taken in the light most favorable to plaintiff, establishes the contributory negligence ... so clearly that no other reasonable inference or conclusion may be drawn therefrom. Discrepancies and contradictions in the evidence, even though such occur in the evidence offered on behalf of plaintiff, are to be resolved by the jury, not by the court. Stathopoulos v. Shook, 251 N.C. 33, 36, 110 S.E. 2d 452, 455 (1959) and .cases cited therein.” Bowen v. Constructors Equipment Rental Co., 283 N.C. 395, 405, 196 S.E. 2d 789, 797 (1973).
 Defendant contends that the failure of the plaintiff to maintain the airport grounds adjacent to the runway but beyond the narrow mowed area outside the lights constituted contributory negligence as a matter of law. We do not agree. While there is evidence in the record from which the jury'could find that plaintiff allowed the area off the runway-to remain rough with high grass and holes, there is nothing in the. record befpre us to raise an inference that the plaintiff violated any duty owed to the defendant with respect to its maintenance of that area. Hence, under the circumstances here presented, we are of the opinion that the evidence is not sufficient to raise an inference of contributory negligence with respect to maintenance of the area adjacent to the runway lights.
 Defendant also contends that the radioed instructions were a direct interference with the safe landing of the aircraft. While there is some evidence from which the jury could find that the plaintiff was negligent, under the circumstances here presented, in undertaking to give any instructions to the defendant regarding the landing of the aircraft and in the instructions that were *113given, and that such negligence was a proximate cause of the damage to the aircraft, we are of the opinion that the evidence raises an issue for the jury but does not establish the plaintiff’s contributory negligence as a matter of law.
For the reasons stated, the judgment directing a verdict for defendant must be reversed and the cause remanded for a new trial.
From the disposition of the plaintiff’s exceptions to the granting of the directed verdict, we find it unnecessary to discuss plaintiff’s exceptions to the evidentiary rulings since they are unlikely to occur at a new trial.
Judges Britt and Martin concur.