Once again, we confront the troublesome task of determining whether a deceased maritime employee was a “member of a crew of any vessel” and is, therefore, excluded from coverage under the Longshoremen’s and Harbor Workers’ Compensation Act (Longshoremen’s Act), 33 U.S.C. § 903. The Administrative Law Judge (ALJ) below, in a decision upheld by the Benefits Review Board, found that pipeline welder Clovis Boudreaux was not a crew member of a pipelaying barge because he was not aboard the vessel “primarily to aid navigation.” We hold that the AU and the Board failed to apply the legal standard used in this circuit to determine crew member’s status. We further hold that the undisputed1 *454factfindings of the ALJ, measured against the correct standard, require our conclusion that Boudreaux was, as a matter of law, a crew member of the barge on which he died. Consequently, we set aside the administrative order affording Boudreaux coverage under the Longshoremen’s Act.
I. The Facts
Boudreaux worked for McDermott as a pipeline welder for approximately nine years prior to his death in 1976. Although Boudreaux occasionally worked on one of McDermott’s onshore operations during a lull in offshore activity, his principal employment during those ten years was as a pipe welder on several of McDermott’s offshore pipelaying barges. As their job title suggests, pipeline welders construct the pipelines that connect offshore wells with onshore distribution facilities. They are essential to the mission of the specially-designed pipelaying barges.
Boudreaux spent part of the summer of 1975, approximately one year before his death, working onshore constructing an aerial crossing (an elevated pipeline) at Whiskey Bay, Louisiana. After working offshore during the fall, he took an optional winter layoff from December 12, 1975 until March 23, 1976. He then reported to work at Bayou Boeuf, Louisiana, and assisted in repairs on board McDermott’s Lay Barge 23. The barge, which had suffered ordinary wear and tear during recent operations in the North Sea, was moored afloat in a slip at McDermott’s yard. By June, the repairs were nearing completion and Boudreaux was scheduled to begin work on another barge offshore. Since he had not welded any pipe offshore during the first six months of 1976, however, Boudreaux had to qualify in a welding test on June 16. Two days after passing the test, he collapsed and died of a heart attack while completing his job aboard the moored barge.
Boudreaux’ widow filed a claim for benefits under the Longshoremen’s Act on March 2, 1977. McDermott contested the claim, arguing that Boudreaux had been a “member of the crew” of McDermott’s pipe-laying barge fleet and, consequently, did not qualify as an “employee” under the Longshoremen’s Act.2 McDermott also contended that Boudreaux had died from cardiac arrythmia induced by arteriosclerosis rather than from any work-related condition. The ALJ heard the case on May 10, 1979. On August 1, the ALJ awarded the benefits to Mrs. Boudreaux, holding that Boudreaux had been an employee covered by the Longshoremen’s Act and that his job had at least contributed to his heart failure. McDermott filed a timely appeal with the Benefits Review Board, but the Board upheld the ALJ on both issues.3 Pursuant to section 21(c) of the Longshoremen’s Act, 33 U.S.C. § 921(c), McDermott has appealed the Board’s decision to this court.
*455II. The Original Test of Crew Members’ Status
As McDermott points out, the ALJ and the Benefits Review Board held the following test to be appropriate for use in determining “crew member” status under the Longshoremen’s Act: whether (1) there is a vessel in navigation; (2) the worker has a more or less permanent connection with the vessel; and (3) the worker is on board the vessel primarily to aid in navigation. This frequently cited “three-prong” test apparently was first distilled from earlier caselaw in Wilkes v. Mississippi River Sand & Gravel Co., 202 F.2d 383, 388 (6th Cir. 1953), cert. denied, 346 U.S. 817, 74 S.Ct. 29, 98 L.Ed. 344 (1953). The Wilkes court fashioned the test as a means of determining whether the decedents of two plaintiffs could qualify as “seamen” under the Jones Act, 46 U.S.C. § 688. However, in describing the issue presented as “whether these cases are governed by the Longshoremen’s and Harbor-workers’ Act ... or by the Jones Act,” the court implicitly recognized that the same test necessarily identifies a seaman covered by the Jones Act and a crew member not covered by the Longshoremen’s Act. This court has concluded “that the same test is to be applied to ascertaining whether a person is a ‘seaman’ for purposes of Jones Act jurisdiction, or is ‘a member of a crew of a vessel’ for the purpose of [denying] Longshoremen’s Act jurisdiction.... ” Hardaway Contracting Co. v. O’Keeffe, 414 F.2d 657, 659-60 (5th Cir. 1968) (citing Boate!, Inc. v. Delamore, 379 F.2d 850, 859 (5th Cir. 1967)). See also Travelers Insurance Co. v. Belair, 412 F.2d 297, 302 (1st Cir. 1969) (“ ‘Seaman,’ as used in the Jones Act and ‘members of the crew’ as excluded from the Longshoremen’s Act, are equivalent terms.”)
This court first adopted the tripartite standard in McKie v. Diamond Marine Co., 204 F.2d 132, 136 (5th Cir. 1953), and most of the federal circuits who regularly hear maritime actions have used some form of the test. See, eg., Salgado v. M. J. Rudolph Corp., 514 F.2d 750, 754 (2d Cir. 1975); Griffith v. Wheeling Pittsburg Steel Corp., 521 F.2d 31, 36 (3d Cir. 1975), cert. denied, 423 U.S. 1054, 96 S.Ct. 785, 46 L.Ed.2d 643 (1976); Whittington v. Sewer Construction Co., 541 F.2d 427, 436 (4th Cir. 1976); Bullis v. Twentieth Century-Fox Film Corp., 474 F.2d 392, 393 (9th Cir. 1973). Not surprisingly, however, each prong of the test has generated its share of interpretative controversy.
Courts have held, for example, that the “vessel in navigation” element does not require the vessel to have been in actual operation at the moment of the injury or death in question. “Case law indicates that a vessel is ‘in navigation’ although moored to a pier, in a repair yard for periodic repairs, or while temporarily attached to some object.” Griffith, supra, 521 F.2d at 37 (citing 2 M. Norris, The Law of Seamen § 668, at 301-02 (3d ed. 1970); see also 1 Benedict on Admiralty § 11a, at 2-7 (7th ed. 1981). In Doucet v. Wheless Drilling Co., 467 F.2d 336 (5th Cir. 1972), this court held that a semisubmersible drilling barge temporarily moored for repairs remained a vessel in navigation. See also Rogers v. United States, 452 F.2d 1149, 1152 (5th Cir. 1971) (missile tracking ship tied to pier for repairs “in navigation”); Bodden v. Coordinated Caribbean Transport, Inc., 369 F.2d 273, 275 (5th Cir. 1966) (freighter in dry dock for repairs still in navigation).4 Thus, the facts in the case before us amply justi*456fied that ALJ’s findings that McDermott’s Lay Barge 23, which remained afloat and under its owner’s control throughout the repair period, was a vessel in navigation.
Similarly, the facts developed at the hearing below support the finding that Boudreaux had a more or less permanent connection with the fleet of barges. The testimony showed that Boudreaux had worked on the repairs aboard Lay Barge 23 from the time he returned from his layoff in March to the time of his death. Moreover, Boudreaux had spent most of his time with McDermott as a welder attached to the company’s fleet of pipeline barges and was scheduled to return to sea on Lay Barge 21 when he died. “[I]t is well established that one need not be indefinitely and invariably assigned to one vessel in order to achieve the ‘permanent’ connection required by this prong of the ... analysis. The permanency requirement may be satisfied by assignment to a specific fleet of vessels.” Ardoin v. J. Ray McDermott & Co., 641 F.2d 277, 281 (5th Cir. 1981) (citations omitted).
The controversy in our case, then, centers on the third prong of the McKie standard, which requires that the worker be aboard primarily to aid in navigation. The ALJ who heard the case observed that Boudreaux had spent only three and one-half months of the year prior to his death working offshore; he had spent the remainder of his time (discounting, presumably, the winter layoff) repairing the moored barge. “However, assuming, arguendo that decedent spent twelve months as a pipeline welder,” the ALJ continued, “his primary duties then were to fit and weld pipeline extending from oil wells to oil distribution facilities.” The ALJ found that these duties did not “primarily aid in navigation” and that Boudreaux was not, therefore, a crew member excluded from coverage under the Longshoremen’s Act.
In affirming this construction of the “aid in navigation” prong, the Benefits Review Board added that Boudreaux had been engaged in ship repair work for two months prior to his death, had received lower pay for this work than for his usual offshore duties, had been living ashore, and had not been “engaged in oil pipeline welding, the special function of the vessel.” Thus, the Board concluded that “[djecedent was clearly a ‘shiprepairman’ in employer’s yard from March 23, 1976, until his death on June 18, 1976.”
We are forced to conclude that these holdings represent a fundamental misunderstanding of the legal construction that this court has placed upon the phrase “aboard primarily to aid in navigation.”5 While agreeing that “the test for determining whether an employee is a member of a crew is the same test used for determining whether a worker is a Jones Act seaman,” the ALJ based his final judgment on a conviction, approved by the Board, that this court’s post-McKie decisions expanding the concept of Jones Act “seaman” are wholly irrelevant to factual inquiries into crew member’s status under the Longshoremen’s Act. Relying on the bare language of the familiar three-part test, the ALJ assumed that Boudreaux’ responsibilities as a pipeline welder on an offshore barge did not qualify as an aid to navigation. In upholding this conclusion, the Board chose to emphasize that Boudreaux’ temporary shift to “ship repair work” on a barge moored at the McDermott yard was sufficient to remove him from the excluded class of crew members. Both views of the law as applied in this circuit are incorrect, since they ignore our interpretation of the “aid to navigation” prong in Offshore Co. v. Robison, 266 F.2d 769 (5th Cir. 1959), and subsequent decisions.
III. Enter Robison.
As McDermott has insisted throughout these proceedings, this Court’s landmark decision in Offshore Co. v. Robison culminated in what might be described as a recasting of the tripartite McKie test for seaman’s sta*457tus. Judge Wisdom’s opinion began by observing the courts had “expanded the coverage of the Jones Act to include almost any workman sustaining almost any injury while employed on almost any structure that once floated or is capable of floating on navigable waters.” 266 F.2d at 771. It further pointed out that the courts had extended this “extremely liberal interpretation to the terms ‘seaman’ and ‘member of a crew of any vessel’ without provoking any congressional amendments restricting the coverage of the Act.” Id. at 774. After a comprehensive review of Supreme Court and federal circuit opinions considering and expanding the meaning of the terms “seaman” and “crew member” under both the Jones Act and the Longshoremen’s Act, the court devised the following as a restatement of this circuit’s position:
[TJhere is an evidentiary basis for a Jones Act case to go to the jury: (1) if there is evidence that the injured workman was assigned permanently to a vessel (including special purpose structures not usually employed as a means of transport by water but designed to float on water) or performed a substantial part of his work on the vessel; and (2) if the capacity in which he was employed or the duties which he performed contributed to the function of the vessel or to the accomplishment of its mission, or to the operation or welfare of the vessel in terms of its maintenance during its movement or during anchorage for its future trips.
Id. at 799 (footnote omitted).
Although we have never abandoned the McKie test and have continued to quote it, e.g. Garcia v. Queen, Ltd., 487 F.2d 625, 628 n.6 (5th Cir. 1973), Robison must be regarded as an essential commentary upon that standard in this Circuit. The two-part Robison version was introduced as a threshold test by which a plaintiff could avoid a summary judgment denying him seaman’s status under the Jones Act. However, our subsequent decisions make clear that the Robison test, with its broad concept of seaman’s status, is to be used not only in deciding whether a case goes to the jury in a Jones Act dispute, but also in delimiting the power of the factfinder to deny or confer such status. Thus, in Producers Drilling Co. v. Gray, 361 F.2d 432, 437 (5th Cir. 1966), we relied on Robison in affirming a district judge’s finding, as a matter of law, that a roustabout working on board a submersible drilling barge was a Jones Act seaman. Obviously, the second prong of Robison represents a necessary gloss upon the third prong of McKie, and no factfinder — whether jury or judge — can overlook the implications of Robison in determining a worker’s status. Effectively, “Offshore Co. v. Robison ... established in the Fifth Circuit the test for seaman status under the Jones Act.” Abshire v. Seacoast Products, Inc., 668 F.2d 832, 835 (5th Cir. 1982).6
Moreover, Robison is fully applicable as a measure of crew member’s status under the Longshoremen’s Act. In Boatel, Inc. v. Delamore, 379 F.2d 850 (5th Cir. 1967), we relied on Robison in holding that a diesel motorman aboard a drilling tender was a “member of the crew,” and therefore not entitled to Longshoremen’s Act benefits, because he was “primarily engaged in performing duties aboard the vessel in fulfilling the function for which the vessel was designed.” Id. at 858. Pointing out that Robison itself had used the terms “seaman” and “member of the crew” interchangeably, we concluded that “[t]he decisions of this Court and the Supreme Courts [sic], in suits under the Jones Act which have decided whether or not a claimant is under the coverage of that Act, are directly applicable here in determining the meaning of the term ‘member of the crew’ for purposes of *458exclusion under the Longshoremen’s Act.” Id. at 859.
Considering Robison’s longstanding and vital importance to this Court’s interpretation of the Longshoremen’s Act, we are at a loss to understand the total disregard of Robison and its progeny in the proceedings below. The ALJ’s assumption that a pipeline welder working on board a pipelaying barge is not employed “primarily in aid of navigation” is clearly out of keeping with the language of Robison and our subsequent interpretations of that decision. Building on the tenet that seaman’s status is not restricted to those who “hand, reef, and steer,” Norton v. Warner, 321 U.S. 565, 572, 64 S.Ct. 747, 751, 88 L.Ed. 931 (1944), this court has relied on Robison in approving the extension of seamen’s or crew member’s status to a number of occupations whose members perform no such traditional navigational chores but nevertheless contribute to the function, mission, or maintenance of a vessel in navigation. See, e.g., Landry v. Amoco Production Co., 595 F.2d 1070 (5th Cir. 1979) (offshore roustabout who operated boat in connection with work); Davis v. Hill Engineering, Inc., 549 F.2d 314 (5th Cir. 1977) (welder’s helper on offshore gas gathering station); Neill v. Diamond M. Drilling Co., 426 F.2d 487 (5th Cir. 1970) (motorman on drilling barge); Noble Drilling Corp. v. Smith, 412 F.2d 952 (5th Cir. 1969), cert. denied, 369 U.S. 906, 90 S.Ct. 221, 24 L.Ed.2d 182 (1969) (mud pumper on drilling tender). In Jenkins v. Aquatic Contractors & Engineers, 446 F.2d 520, 521 (5th Cir. 1971), we affirmed a district court’s holding that the plaintiff, a welder on a pipelaying barge, “was a Robison seaman as a matter of law.... ” See also Welch v. J. Ray McDermott & Co., 336 F.Supp. 383 (W.D.La.1972) (welding inspector on pipelaying barge a “seaman”).
Similarly inexplicable is the Board’s assumption that Boudreaux’ temporary assignment to repair duties aboard the moored barge dissociated him from the barge fleet’s crew. If Boudreaux was normally a crew member of these barges during their missions at sea, as he surely was, there is no reason to presume that he suddenly metamorphosed into a harbor worker or “shiprepairman” just because his employer temporarily used him to prepare a damaged vessel for its next voyage. As the Supreme Court explained in Senko v. La Crosse Dredging Corp., 352 U.S. 370, 373, 77 S.Ct. 415, 417, 1 L.Ed.2d 404 (1957):
Even a transoceanic liner may be confined to berth for lengthy periods, and while there the ship is kept in repair by its “crew.” There can be no doubt that a member of its crew would be covered by the Jones Act during this period, even though the ship was never in transit during his employment. In short, the duties of a man during a vessel’s travel are relevant in determining whether he is a “member of a crew” while the vessel is anchored.
Following this reasoning in Doucet v. Wheless Drilling Co., 467 F.2d 336 (5th Cir. 1972), we affirmed a summary judgment (confirming seaman’s status) for a member of the drilling crew on a semisubmersible barge. The employee had been injured while assisting with repairs to the barge, which had suffered damages in a hurricane and was moored temporarily to the bank. We agreed with the district court that “[plaintiff’s status as a seaman, by reason of being an offshore oil worker on a semi-submersible drilling barge, was not lost because he was on temporary assignment in his employer’s service to do repair work with the intent of returning to an offshore seaman’s work.” 467 F.2d at 338-39.
We conclude, therefore, that Boudreaux, like Doucet, was a member of the barge crew as a matter of law. The evidence showed that Boudreaux had worked for McDermott as an offshore pipeline welder for nine years. Emory Belton, Boudreaux’ supervisor, testified that pipeline welders ordinarily spend over ninety percent of their time offshore and work in the repair yard only when maintenance work is necessary “to keep the equipment up so it’s functioning properly when [the crew gets] offshore.” Although the ALJ reasonably found that Boudreaux himself had spent *459“no more than three and one-half months” of the year prior to his death working offshore, the undisputed evidence also showed that Boudreaux had spent most of his actual working time (not including the winter layoff) that year employed on board a McDermott barge, either at sea or beside the bank. At the time of his death, he was temporarily engaged in repair work aboard Lay Barge 23, readying it for future service offshore. According to the AU’s own findings, Lay Barge 23 remained “in navigation” throughout this repair period and Boudreaux maintained a permanent association with it. His job classification as a pipeline welder never changed. In fact, only two days before his fatal heart attack he re-qualified to return to sea aboard Lay Barge 21. Given these uncontroverted facts, one cannot escape the conclusion that Boudreaux was (1) a member of the crew of Lay Barge 23, or at least of the fleet of which Lay Barge 23 was a unit, in that his duties contributed “to the operation or welfare of the vessel in terms of its maintenance during its movement or during anchorage for its future trips,” Robison, 266 F.2d at 779, and (2) a member of the crew of the barge fleet in general, in that his duties as a pipeline welder contributed “to the function of the vessel[s] or to the accomplishment of [their] mission.... ” Id. As such, he is barred from coverage under the Longshoremen’s Act.
In excluding Boudreaux from coverage, we wish to emphasize our recognition that the Longshoremen’s Act, like the Jones Act, requires a liberal interpretation in favor of claimants to effect its purposes. See, e.g., Voris v. Eikel, 346 U.S. 328, 333, 74 S.Ct. 88, 91, 98 L.Ed. 5 (1953). We do not lightly exclude workers from coverage as a matter of law under either statute. Thus, despite our continued insistence that a Jones Act “seaman” and a “crew member” excluded from the Longshoremen’s Act are one and the same (in other words, that the statutes are mutually exclusive) we realize that, in a practical sense, a “zone of uncertainty” inevitably connects the two Acts. Confronted by conflicting evidence concerning a worker’s duties or undisputed evidence concerning an occupation that exhibits the characteristics of both traditional land and sea duties, a factfinder might be able to draw reasonable inferences to justify coverage under either statute.7 Were this possibility present here, we would remand this case for further factual development at the administrative level and reconsideration in light of our emphasis upon Robison, Jenkins, Doucet, and other precedent in this Circuit.
This is not, however, what we recently described in Abshire v. Seacoast Products, Inc., 668 F.2d 832, 835 (5th Cir. 1982), as “a close case.” Abshire offers a classic instance of the case that could have gone either way. Plaintiff produced evidence that he was a marine welder and mechanic permanently assigned to a fleet of fishing vessels and spent most of his time performing repairs aboard the employer’s boats; defendant produced evidence that plaintiff was a shore-based maintenance employee who never went to sea and whose only contact with vessels under way “was in testing them in connection with repairs and maintenance.” Id. at 836. The district court properly submitted the issue to a jury, which found that the welder/mechanie was entitled to damages as a Jones Act seaman. Although we affirmed the judgment, we just as easily could have approved a jury’s finding that Abshire was restricted to compensation under the Longshoremen’s Act. Incidentally, the judgment for Abshire under the Jones Act also ordered repayment of two insurers that already had compensated him under the Longshoremen’s Act.
*460The case before us presents no such factual or legal uncertainties, particularly when reviewed against past decisions of this court resolving similar disputes over the classification of comparable duties. “The proper legal standard coupled with undisputed facts showing plaintiff’s substantial work relating to vessels in navigation makes clear that reasonable persons could not conclude that [plaintiff] was not a seaman.” Landry v. Amoco Production Co., 595 F.2d 1070, 1074 (5th Cir. 1979). We hold, therefore, that Boudreaux is excluded from coverage under the Longshoremen’s Act as a matter of law, and we SET ASIDE the Board’s order. See, e.g., Dravo Corp. v. Banks, 567 F.2d 593, 596 (3d Cir. 1977).
. The facts are undisputed in more ways than one. Despite repeated notices, neither Boudreaux nor the Department of Labor, appellees in this case, favored us with briefs or appear*454ances at oral argument. Our rendition of judgment for appellant, however, lies solely on facts found by the ALJ, uncontroverted in the record, and used below to support the judgment for appellee Boudreaux.
. Section 2 of the Act defines the term “employee” as
any person engaged in maritime employment, including any longshoremen or other person engaged in longshoring operations, and any harborworker including a ship repairman, shipbuilder, and shipbreaker, but such term does not include a master or member of a crew of any vessel, or any person engaged by the master to load or unload or repair any small vessel under eighteen tons net.
33 U.S.C. § 902(3).
Section 3 of the Act states that “[n]o compensation shall be payable in respect of the disability or death of — (1) A master or member of a crew of any vessel.... ” 33 U.S.C. § 903(a)(1).
. The Board also assessed an additional penalty against McDermott, holding that McDermott failed to controvert the claim within fourteen days of acquiring knowledge of Boudreaux’ death, as required by § 14(d) of the Act, 33 U.S.C. § 914(d). McDermott argues that the Longshoremen’s Act requires not only knowledge that an injury has occurred, but also knowledge that it is job-related.
Because we hold that Boudreaux is excluded from coverage under the Act, we need not decide whether Boudreaux’ injury was compensable or McDermott’s controversion was timely.
. In Doucet, 467 F.2d at 339, we noted that the vessel held to be in navigation was “within the control of the owner, ... it was partially afloat, the repairs were chiefly to drilling equipment, the time was short, and the vessel quickly returned to its drilling function as soon as a contract was secured and before repairs were fully done.” In Rogers, 452 F.2d at 1152, we emphasized that the magnitude of the repairs and the owner’s retention or release of control were important considerations in determining the vessel’s status. In Bodden, 369 F.2d at 275, however, we pointed out that “where a vessel is laid up for the winter, the crew having been discharged, and the boat is being secured by workmen paid at an hourly rate and living ashore, the ship is no longer in navigation.” Obviously, no single factor controls an evaluation of a vessel’s status, although control over the vessel and magnitude of the repairs are important subjects for inquiry.
. Since the Board acts in an adjudicatory rather than an enforcement capacity, we need not defer to its construction of the Longshoremen’s Act in reviewing its determinations for errors of law. See Miller v. Central Dispatch, Inc., 673 F.2d 773 at 779 & n.12 (5th Cir. 1982).
. A panel of this court recently examined a Jones Act claim using what it referred to as a “McKie/Robison analysis.” Ardoin, supra, 641 F.2d at 281. As if to complete the conjunction of the old and the new, other panels have preferred to edit the two-part statement of Robison into a three-pronged standard reminiscent of McKie. See Barrios v. Engine & Gas Compressor Services, Inc., 669 F.2d 350, 352 (5th Cir. 1982); Watkins v. Pentzien, Inc., 660 F.2d 604, 606 (5th Cir. 1981), cert. denied,-U.S. —-, 102 S.Ct. 2010, 72 L.Ed.2d 467 (1982).
. Even the ambiguous employee must elect a remedy, however. Section 5 of the Longshoremen’s Act, 33 U.S.C. § 905, provides that the employer’s liability under the Act is an exclusive remedy. Thus, we have held that the Longshoremen’s Act and the Jones Act are “mutually exclusive,” Bodden, supra, 369 F.2d at 274, and that establishment of an employer’s liability under the Longshoremen’s Act “effectively abrogates any independent tort liability of the employer to its employees....” Ocean Drilling & Exploration Co. v. Berry Brothers Oilfield Service, Inc., 377 F.2d 511, 514 (5th Cir. 1967), cert. denied, 389 U.S. 849, 88 S.Ct. 102, 19 L.Ed.2d 118 (1967).