MEMORANDUM *
We have jurisdiction under 49 U.S.C. § 46110, and we deny the petition.
A. Fuel Pump Violations
When considered together, Steven Rimer’s (“Rimer”) testimony and the maintenance records for the two fuel pumps constitute substantial evidence supporting the Federal Aviation Administration (“FAA”) Administrator’s conclusion that Rimer modified those pumps. Although Rimer’s lack of independent recollection raised the possibility that he did not in fact modify the pumps, that does not mean that substantial evidence is lacking. A conclusion may be supported by substantial evidence even though a plausible *608alternative interpretation of evidence would support a contrary view.2
As to the safety of the fuel pumps, FAA investigators John Gamble and James Tupper testified that modifying the fuel pumps without installing screws at the proper torque values could lead to fuel leaks. Rimer admitted at the hearing before the Administrative Law Judge (“ALJ”) that when modifying the fuel pumps, he did not follow the manufacturer’s instructions which specify the procedures for ensuring proper torque values. Thus, there is substantial evidence to support the Administrator’s conclusion that the fuel pumps were not airworthy, i.e., not properly maintained according to specifications.3
Rimer’s pre-hearing statements do not show that Rimer installed the screws at the proper torque values. Rimer made those statements in the context of arguing that he-in addition to the manufacturer-was authorized to modify the fuel pumps. Rimer’s statements never mentioned torque values or other specifics relating to the procedures he used when modifying the fuel pumps.4
Finally, the ALJ did not erroneously conclude that there was no evidence casting doubt on Rimer’s credibility. All we can tell from the ALJ’s decision is that he did not consider the fact that Warbelow’s Air Ventures (“Warbelows”) fired Rimer a sufficient “basis for concluding that Mr. Rimer had reason to [testify] contrary to the truth of the matter.” As the ALJ was in the best position to evaluate Rimer’s credibility, we will not disturb the ALJ’s conclusions so long as the ALJ considered all the evidence. There is no indication that he did not do that.
B. Emergency Locator Transmitter (“ELT”) Violation
The FAA has interpreted “inoperable” in 14 C.F.R. § 135.179 to mean that an instrument is not working as intended.5 Because Warbelows’ alternative interpretation-that an instrument is “operable” if it is working, even though not as intended-is not compelled by § 135.179’s plain language, we reject it.6
We also hold that there is substantial evidence to support the Administrator’s decision that Warbelows’ ELT was “inoperable” during the flight in question. Gamble testified that the ELT’s internal *609antenna is not the same as the external antenna, that the internal antenna’s ability to transmit a signal is limited because it is shielded by the fuselage and surrounding wiring, and that the reason for the internal antenna is so the ELT can be used in the event there is an aircraft evacuation.7
Furthermore, there is evidence that suggests Warbelows realized that its ELT was not working as intended. The ALJ found that the entry, “MEL’ed per 25-1-4,” in the maintenance records referred to the ELT, not just the external antenna. Even Arthur Warbelow understood that an external antenna was not a superfluous instrument. Although Warbelows’ demonstration at the hearing is evidence suggesting that its ELT was working as intended, that demonstration is of limited probative value because it transmitted a signal over a mere thirty feet.
PETITION DENIED.