The plaintiff-appellant, Charles Seymour, was injured while participating in the loading of the M/V Montego on May 22, 1967, at Miami, Florida. Seymour sued M. R. Harrison Crane Service for damages for personal injury sustained as a result of Harrison’s alleged negligence. Third-party complaints, counterclaim and cross-claims followed. The trial judge, after hearing the case without a jury, entered a final judgment in favor of the defendant-appellee Harrison as to Seymour’s claim for negligence and as to an indemnity claim brought against Harrison by Eagle Shipping Corporation, the company in charge of the stevedoring operation at the time of the accident. Seymour and Eagle appeal.
The M/V Montego has a large opening or hatchway on its weather deck. Below the weather deck was the shelter deck with openings for two hatches; the six-foot wide portion of the shelter deck between the two hatches is the “tween deck” or “dividing deck”. On May 22, 1967, the M/V Montego was being loaded. Eagle Shipping-Corporation was in charge of the stevedoring operation, and Seymour was employed by Eagle. Eagle had, by oral contract, engaged the M. R. Harrison Crane Service to furnish cranes and personnel to assist with the loading. Harrison was operating two cranes from the dock to load the two hatches. Longshoremen brought pallets of cargo onto the dock from a nearby warehouse and attached them to the crane cables. The crane lifted the pallet from the dock to the vessel where longshoremen placed the cargo in the holds.
*1187Hatch Number One was nearly filled at the time of the accident, so, instead of depositing the loaded pallets directly in the hold, the crane placed the pallets on the “tween deck” where longshoremen Bernard Conyers and Joseph Ragin handed the cargo to other men in the hold. Seymour was working inside Hatch Number Two. Because that hold was not yet fully loaded, the crane deposited the pallets directly into that hold.
At approximately 11:45 a. m. the crane transported a pallet for Hatch Number One toward the “tween deck”. It is uncontroverted, and the trial judge found, that this pallet was “improperly loaded, that is, the cargo thereon extended over the sides of the pallet and was not balanced properly on the pallet”. Several boxes fell off the overloaded pallet, into Hatch Number Two, injuring Seymour. There was contradictory evidence as to whether the boxes fell before or after Conyers and Ragin released the bridle around the cargo. It is uncontra-dicted, and the trial judge found, that “there was considerable dunnage and ropes in the area of the partition separating hatch #1 and hatch #2 on the ‘tween deck’.” The dunnage and ropes caused the pallet to tilt.
Seymour sued the shipowners, Oceanic Navigation Company and Pan American Mail Lines, for negligence and breach of warranty and the crane service, Harrison, for negligence. Harrison and the shipowners filed third-party complaints against Eagle, the stevedore, contending that Eagle was responsible for the accident, and Eagle counterclaimed against the shipowners and cross-claimed against Harrison. Before trial Seymour settled with the shipowners and the shipowners settled with Eagle. The case therefore went to trial on Seymour’s claim against Harrison and Eagles’ claim for indemnity against Harrison.
At the trial, the plaintiff presented only one witness on the question of liability, Bernard Conyers. Conyers testified as, to his eyewitness account of the accident. Cross-Examination and impeachment by use of a prior inconsistent statement revealed contradictions in Conyers’s testimony. On direct examination, he testified that he saw the pallet descending in an “overloaded and listing” condition and that he released the bridle from around the cargo before the boxes began to fall.1 Oncross-examination, defense counsel, by inaccurately summarizing Conyers’s direct testimony, elicited contradictory testimony to the effect that Conyers did not loosen the bridle before the boxes fell.2 Then, in an effort to impeach Conyers, the defense presented a statement prepared by *1188Conyers and Ragin three months after the accident.3 The statement, although inconsistent with the cross-examination testimony, was consistent with the direct testimony in that it stated that Conyers had taken the bridle off the cargo before it fell. The statement, however, made no mention of the pallet descending in an overloaded condition.
Also, several witnesses, including two crane operators employed by Harrison, an executive of Eagle, and Conyers, presented uncontradicted testimony that the crane operator has a clear view of the load on the pallet and that it is common practice and “common sense” for a crane operator to return an overloaded pallet to the dock.4
*1189The trial court entered findings of fact and conclusions of law 5 and entered final judgments in favor of Harrison, both as to Seymour’s claim for negligence and Eagle’s claim for indemnity, Both Seymour and Eagle have appealed.
*1190Seymour urges us to reverse the decision of the district court because, in his view, the findings of fact entered by the court present a prima facie case of negligence. This we decline to do. Instead, we remand the case to the district court for clarification of, what we believe to be, self-contradictory and confusing findings.
In Finding of Fact Number 4, the court stated:
The pallet was improperly loaded, that is, cargo thereon extended over the sides of the pallet and was not balanced properly on the pallet.
This finding, when considered in light of the uncontradicted testimony that a crane operator has a clear view of the load on a pallet and returns an overloaded pallet to the dock as a matter of “common sense”, would appear to establish a prima facie case of negligence. The findings may, however, be interpreted as denying liability, assuming the existence of a duty of care and a negligent breach of that duty, because of the absence of causation. In other words, because the district court found that “there was considerable dunnage and ropes ... on the ‘tween deck’ ” which “caused [the pallet] to tilt . . . causing some of the cargo to fall from the pallet and striking the plaintiff (see footnote 5), the court may have concluded that the longshoremen in the employ of Eagle were responsible for the accident in that they failed to remove the dunnage and ropes from the “tween deck”. Alternatively, the trial court may have found the longshoremen responsible for the accident in that they, and not the employees of Harrison, improperly loaded the pallet. This interpretation of the district court’s opinion is plausible in light of the court’s care in finding Harrison “had nothing to do with the actual loading of the cargo unto the pallet”. (See footnote 5)
Under either interpretation of the district court’s finding as to causation, the negligence of the longshoremen would not absolve Harrison from liability but rather serve as a concurrent cause of the accident. Although the accident might not have occurred without the negligence of the longshoremen in leaving the dun-nage and ropes on the deck or improperly loading the pallet, the act of the Harrison employees of transporting an overloaded pallet to the ship was a concurrent, contributing cause of the accident. Had the crane operator returned the pallet to the dock when he saw it was overloaded, as was common practice, the accident would not have occurred.
There is a second source of confusion in the opinion of the district court. The court found:
Plaintiff’s sole liability witness [Conyers] was not believable or entitled to any credence or weight because much of his testimony at the trial was in direct conflict and contradiction with his signed statement which was introduced into evidence at the trial.
Despite the apparent total rejection of Conyers’s testimony, the district court used portions of that testimony as a basis for its findings. There was no other evidence upon which the district court could have based its version of the accident reflected in the findings; Conyers was the only liability witness. Although a trial court may, of course, choose to reject certain portions of a witness’s testimony while accepting other portions, *1191the court’s total rejection of Conyers’s testimony leaves us in doubt as to the source of the court’s findings. A trial judge may not use his disbelief of a witness as affirmative support for the proposition that the opposite of the witness’s testimony is the truth. See Ni-shikawa v. Dulles, 1958, 856 U.S. 129, 78 5. Ct. 612, 2 L.Ed.2d 659; Moore v. Chesapeake & Ohio Railway Co., 1951, 340 U.S. 573, 71 S.Ct. 428, 95 L.Ed. 547.
Nor could the trial court’s conclusions be based on the signed statement of Conyers and Ragin describing the accident. (See footnote 3) The statement, initially used to impeach Conyers, was offered as substantive evidence by the plaintiff. The trial judge accepted the statement into evidence, but stated, at the close of all evidence, that he was “not considering it as substantive evidence of what actually happened . . . ” 6. This total rejection of the statement as substantive evidence is not only puzzling because it leaves the record barren of a possible source for the district court’s findings, but also it totally ignores the fact that the statement was signed by Joseph Ragin as well as by Conyers. Ragin was not presented as a witness and, obviously, was not impeached.
Because the district court’s findings of fact are self-contradictory, confusing, and inconsistent with the court’s statements at trial, we must remand the case to the district court for clarification of the findings.
In addition to clarifying the findings on remand, the district court should consider the relevance and applicability of certain regulations of the Bureau of Labor Standards. These regulations, entitled “Safety and Health Regulations for Longshoring”, appear in 29 C.F.R. Part 1504. Particular attention is directed to 29 C.F.R. § 1504.81 dealing with “Slinging” and 29 C.F.R. § 1504.82 dealing with “Building Drafts”.7 The *1192district court’s findings would appear to establish a violation of these regulations, and a violation of these regulations would serve as a predicate for a finding of negligence. See Manning v. M/V Sea Road, 5 Cir. 1965, 358 F.2d 615.
Eagle Shipping Corporation appeals from the district court’s final judgment denying Eagle’s indemnity claim against Harrison. Because the trial court found that “there was no showing whatsoever of negligence” on the part of Harrison, Eagle’s indemnity claim, of course, failed. (See footnote 5) If, on remand, the district court finds Harrison negligent in any manner or that Harrison breached its alleged warranty of workmanlike performance, the court should consider Eagle’s claim for indemnity.
The case is remanded to the district court for proceedings not inconsistent with this opinion.