JOHNSON, Circuit Judge:

Texas-U.S. Chemical Company seeks a reversal of the judgment entered in favor of its former employee, E.D. Hayden, on his claim for benefits under the company's permanent and total disability benefit plan. The judgment must be vacated, but for reasons other than those pressed by the company: it is not possible to discern the basis for the judgment in the findings of fact and conclusions of law set forth by the district court. We remand for reopening of proceedings and reconsideration of Hayden's claim.

I.

In September 1967 Hayden took a job as a laborer in Texas-U.S. Chemical's Port Neches, Texas rubber manufacturing plant. Hayden was hired over the objections of company physicians: his pre-employment physical examination disclosed an abnormality in the vertebral structure of his lower back which created a predisposition to serious injury from the strains associated with hard manual labor. Hayden sustained several such injuries in the course of his employment with Texas-U.S. Chemical; because of those injuries, his condition worsened into lumbar disk syndrome aggravated by secondary arthritis. He refused, however, to undergo the surgery recommended by company and private physicians, out of a fear that unsuccessful surgery would leave him disabled.

Hayden was laid off in January 1975 as a result of a general reduction in force. In May 1975, he underwent the first of what would become a series of corrective operations. Notice to Texas-U.S. Chemical of his surgery resulted in a change of his employment status from "laid off" to "medical leave of absence." Hayden remained in that status until he was terminated for medical reasons in June 1978.

In the fall of 1978, Hayden applied for benefits under the company's Permanent and Total Disability Plan (the Plan). Hayden's claim for benefits was denied on the grounds that because his disability occurred while he was in layoff, rather than active, status, and because he had in any case failed to show his disability to be permanent, he had failed to satisfy the eligibility requirements set out in the Plan.

Hayden subsequently initiated legal action charging Texas-U.S. Chemical with breach of contract through a denial of benefits, in contravention of the terms of the collective bargaining agreement. The suit proceeded as one governed wholly by Texas law until the day of trial, when Hayden first raised his claim to relief under the Employee Retirement Income Security Act of 1974 (ERISA), 29 U.S.C. § 1001 et seq. The company strenuously objected to Hayden's interjection of a federal ground for relief, and for sound reason: its defense rested in large measure on the deference accorded private employment agreements under Texas law.

Texas-U.S. Chemical's first line of defense was drawn from Art. V ¶ 3 of the Plan, which states that

This Plan is entirely voluntary on the part of the Company. An employee acquires neither a vested nor a contractual right hereunder . . . .

Joint Exhibit at DF-7. The company interpreted this provision to mean that its payment of benefits under the Plan was wholly discretionary, and pointed to Texas cases holding that "benevolent claims" could not be made legally enforceable in the face of contract provisions expressly denying contractual liability therefore. Parrott v. Brotherhood of Railroad Trainmen, 85 S.W.2d 306 (Tex.Civ.App.-Texarkana 1935, writ ref'd n.r.e.); Rieden v. Brotherhood of Railroad Trainmen, 184 S.W. 689 (Tex.Civ.App.-San Antonio 1916, writ ref'd n.r.e.).

The company's fall-back argument also relied on the limited degree of regulation imposed by Texas law on employee benefit plans. Art. II ¶¶ 1 and 3 and Art. V ¶ 1 of the Plan placed authority to determine eligibility for benefits in Texas-U.S. Chemical alone; Art. III ¶ 1(b) disallowed benefits to covered employees whose disabilities occurred while laid off. Under Texas law, determinations of benefit eligibility made under such provisions are "not subject to attack in the courts in the absence of a showing of fraud or bad faith," Long v. Southwestern Bell Telephone Co., 442 S.W.2d 462, 464 (Tex.Civ.App.-San Antonio 1969, writ ref'd n.r.e.); accord, Marsh v. Greyhound Lines, Inc., 488 F.2d 278, 280 (5th Cir. 1974) (applying Texas law). The company claimed that the abundance of evidence in support of its decision conclusively eliminated the possibility that its refusal to pay Hayden's claim was motivated by either fraud or bad faith.

The case was tried without a jury. Hayden's post-trial brief more clearly set out his theories of the company's liability under ERISA; the company continued to claim that Texas law alone could be applied. The district court failed to resolve this dispute in rendering judgment. Although it concluded as a matter of law that

The Permanent and Total Disability Plan of Defendant is a welfare benefit plan as defined in the Employee Retirement Income Security Act of 1974 (ERISA), Section 1002. As a welfare benefit plan, the plan administrators and fiduciaries are subject to the reporting and disclosure requirements, the fiduciary responsibilities and the plan administration and enforcement obligations provided for by ERISA.

Record Vol. I at 179, and based its award of attorneys' fees to Hayden in part on ERISA's provision for such an award, ERISA § 502(g), 29 U.S.C. § 1132(g), it made no finding that Texas-U.S. Chemical's denial of benefits to Hayden violated any provision of ERISA. Judgment rested instead on an unsupported, conclusory factual finding that, though the Plan could be terminated unilaterally by the company, and though it specifically denied the existence of contractual claims to benefits, a "right to benefits under the plan did accrue [to Hayden] while an employee of [Texas-U.S. Chemical]," id. at 177, and the denial of benefits was in bad faith, id. at 178. Hayden was awarded damages and attorneys fees in excess of $30,000.

Texas-U.S. Chemical appeals, contending the district court's decision that Hayden had an enforceable claim to benefits to be without basis in law, and the conclusion that the refusal to pay was in bad faith to be without basis in fact. Hayden argues that the award should be upheld by identification of an ERISA-granted right to those benefits and a finding that that right was abridged.

This Court can do neither. The district court's failure to resolve the dispute over applicable law was fatal. The case must be reconsidered.

II.

Rule 52(a), Fed.R.Civ.P., requires that "[i]n all actions tried upon the facts without a jury . . ., the court shall find the facts specially and state separately its conclusions of law thereon. . . ." Clear and adequate factual findings and complete legal analysis in the district court lay the foundation essential to sound appellate review. Without them this Court cannot know whether the district court's reasoning was correct. They are absent here.

The paucity of legal analysis and the absence of specific, supporting factual determinations leaves this Court unable to identify, let alone evaluate, the basis for the district court's decision. Nor may this Court, as Texas-U.S. Chemical urges, assume it to be in Texas law. Hayden's claim to relief under ERISA does not state merely an alternative theoretical formulation of his cause which may fairly be disallowed if late presented, cf. Bettes v. Stonewall Insurance Co., 480 F.2d 92 (5th Cir. 1973). Rather, ERISA, if applicable, displaces the otherwise governing state law. Alessi 101 S.Ct. at 1906; Woodfork v. Marine Cooks Stewards Union, 642 F.2d 966, 969-74 (5th Cir. 1981); see Delta Airlines v. Kramarsky, 666 F.2d 21, 24-25 (2d Cir. 1981), modifying 2nd Cir. 650 F.2d 1287, prob. juris. noted ___ U.S. ___, 102 S.Ct. 1968, 72 L.Ed.2d 439 (1982); Murphy v. Heppenstall Co., 635 F.2d 233, 237 (3d Cir. 1980), cert. denied, ___ U.S. ___, 102 S.Ct. 999, 71 L.Ed.2d 293 (1982); Kapuscinski v. Plan Administrator, etc., 658 F.2d 427, 430 (6th Cir. 1981); Dependahl v. Falstaff Brewing Co., 653 F.2d 1208, 1215 (8th Cir.), cert. denied, 454 U.S. 968, 102 S.Ct. 512, 70 L.Ed.2d 384 (1981); Standard Oil Co. of California v. Agsalud, 633 F.2d 760, 763, 765 (9th Cir. 1980), affirmed, 454 U.S. 801, 102 S.Ct. 79, 70 L.Ed.2d 75 (1981). The Congress has stated, by a preemptive provision at the heart of ERISA, its intention to clear the field of employee benefit plan regulation for federal control, ERISA § 514(a), 29 U.S.C. § 1144(a); Alessi 101 S.Ct. at 1906; Woodfork at 970; Delta, 666 F.2d at 24-25; Dependahl at 1215; it has, by this clear expression, authorized the federal courts to formulate a federal common law of substantive rights filling the interstices of ERISA's statutory provisions. Woodfork at 973; Paris v. Profit Sharing Plan, 637 F.2d 357, 361 (5th Cir.), cert. denied, 454 U.S. 836, 102 S.Ct. 140, 70 L.Ed.2d 117 (1981); Murphy at 237; Dependahl at 1216; compare Delta Airlines v. Kramarsky, 650 F.2d at 1304. It is essential that the question of ERISA's application be determined. The case cannot proceed without resolution of this threshold issue. Compare Woodfork at 969-74.

It will be necessary, then, for the district court to consider and expressly to decide whether Hayden's claim is governed by ERISA. As an initial matter, it must determine whether the plan falls within any exemption to ERISA's supercedure provision, see, e.g., Alessi 101 S.Ct. at 1906-07; Delta, 666 F.2d at 24-26; Kapuscinsky at 429-30; Standard Oil at 764-65, or whether Hayden's cause of action arose or is occasioned by acts or omissions occurring before the January 1, 1975 effective date of that provision. See Woodfork at 970-74; Paris at 360-61. If those matters are resolved in favor of ERISA coverage, it will be necessary to construe the plan provisions on which Texas-U.S. Chemical relies in light of ERISA's substantive provisions; if no statutory provisions are found directly to govern, the district court must acquit its obligation to develop and apply federal common law consonant with the objectives established by that comprehensive scheme. Woodfork at 973 n. 8; Murphy at 237-39; Dependahl at 1217. Specifically, the district court must address the construction to be given under ERISA to the plan's denomination as "voluntary," see, e.g., Trustees, Atlanta Ironworkers Pension Fund v. Southern Stress Wire Corp., 509 F. Supp. 1097 (N.D.Ga. 1981); Calhoun v. Falstaff Brewing Co., 478 F. Supp. 357 (E.D.Mo. 1979), and the force to be allowed its disclaimer of creation of contractual rights, see ERISA § 502(a)(1)(B), 29 U.S.C. § 1132(a)(1)(B); Woodfork at 972. If the company's decision is found to be susceptible to legal challenge, that decision must be reviewed for arbitrariness or capriciousness. Paris at 362; Bayles v. Central States, Southeast and Southwest Areas Pension Fund, 602 F.2d 97, 99, 100 n. 3 (5th Cir. 1979).

If the district court determines that ERISA does not govern Hayden's claim, its decision must be rendered under Texas law. A decision in favor of Hayden under Texas law must be accompanied by, inter alia, a reasoned interpretation of Texas law demonstrating that, notwithstanding Plan provisions to the contrary, a legally enforceable right to benefits did accrue to Hayden.

The questions remaining are many. It will be necessary to reopen proceedings for the advice and assistance of counsel on the issues we have identified, and on any other issues relevant to resolution of Hayden's claim believed pertinent by the parties. We leave, however, to the discretion of the trial court whether a fuller development of the factual basis for a decision requires acceptance of additional evidence.

III.

The judgment is vacated and the case remanded for further proceedings consistent with this opinion.

VACATED AND REMANDED WITH INSTRUCTIONS.