dissenting:
Gonzalez was convicted, on a plea of guilty, of one count of interference with a flight crew member in violation of 49 U.S.C. § 46504. Accepting the recommendation of the Probation Officer, the district court doubled Gonzalez’s base offense level—from level 9 to level 18—for recklessly endangering the safety of the aircraft under U.S.S.G. § 2A5.2(a)(2) without making any specific finding of fact that the safety of the aircraft was, indeed, endangered. Because I disagree that this enhancement is applicable in this case, I respectfully dissent.
Even reading the sentencing record and all of the materials available to the district court at sentencing in the light most favorable to upholding the sentence, the record does not come close to establishing that Gonzalez posed any threat to the aircraft in this case. Based on the plain meaning of § 2A5.2(a)(2), whether or not Gonzalez’s conduct threatened the flight attendants and passengers is a separate question, to which this enhancement does not speak. The majority mistakenly conflates the two concepts—threat or endangerment of a flight attendant and endangerment of the aircraft. Acceptance of the majority’s reasoning would render the enhancement un*1041der § 2A5.2(a)(2) applicable to virtually every case for violation of 49 U.S.C. § 46504. This is contrary to the Guideline’s unambiguous language and the clear intent of the Sentencing Commission.
“This Court applies the rules of statutory construction when interpreting the Sentencing Guidelines.... If the language of a statute is unambiguous, the plain meaning controls.” United States v. Robinson, 94 F.3d 1325, 1328 (9th Cir.1996); see also United States v. Carter, 421 F.3d 909, 911—12 (9th Cir.2005) (examining the meaning of U.S.S.G. § 2K2.1(b)(4) according to the rules of statutory construction). In assessing plain meaning, “ ‘unless otherwise defined, words will be interpreted as taking their ordinary, contemporary, common meaning.’ ” Carter, 421 F.3d at 911 (quoting Perrin v. United States, 444 U.S. 37, 42, 100 S.Ct. 311, 62 L.Ed.2d 199 (1979)).
As applicable here, § 2A5.2(a)(2) calls for an enhancement “if the offense [of interference with a flight crew member or flight attendant] involved recklessly endangering the safety of ... an airport or an aircraft.” U.S.S.G. § 2A5.2(a)(2) (emphasis added). To take a typical definition, an “aircraft” is “a weight-carrying machine or structure for flight in or navigation of the air.” Webster’s Third New International Dictionary (Unabridged) 46 (2002).
The majority improperly disregards the plain meaning of “aircraft” and includes “flight attendants and passengers” within the meaning of “aircraft.”1 Under the majority’s reading, no risk or endangerment to the aircraft itself or any of its components need be present in order for § 2A5.2(a)(2) to apply. The facts in this case vividly illustrate why the majority’s interpretation of the Guideline is untenable, notwithstanding its unsupported and bald assertion that “Gonzalez’s irresponsible statements, threats and conduct easily qualified as reckless endangerment to ‘the safety of ... an aircraft’ within the meaning of § 2A5.2(a)(2).” Maj. op. at 1035.2
In this case, there was no bomb on the plane, and there is no evidence that Gonzalez’s empty (and empty-handed), panicked threat endangered the safety of the machine or structure composing the “aircraft.” Contrary to the majority’s suggestion, the fact that flight attendants and passengers were disturbed, even panicked, and the plane was turned around is insufficient to meet the Guideline.3 There was *1042no evidence presented in this case, through testimony from the pilot or otherwise, that the pilot’s ability effectively to operate the plane was inhibited, or that the diversion caused any; risk to aircraft safety. Also lacking any evidence that the return of the aircraft to Las Vegas precipitated any danger, moreover, this case is distinguishable from the cases upon which the majority relies.4
Most importantly, the majority improperly relies on United States v. Naghani, 361 F.3d 1255 (9th Cir.2004). Contrary to the majority, I do not believe that Nagha-ni controls and I conclude that what constitutes endangerment of the aircraft is an open question. First, Naghani is not binding because the court did not consider the meaning of “aircraft” or what level of interference satisfied the Guideline. These questions were never squarely raised. Instead, the briefing was geared towards the question of what constituted reckless conduct, and there is no indication that the court contemplated the issues addressed here, namely the definition of “aircraft” or the specific meaning of that enhancement. See Local 144 Nursing Home Pension Fund v. Demisay, 508 U.S. 581, 592, 113 S.Ct. 2252, 124 L.Ed.2d 522 (1993) (characterizing as dicta writings that were “uninvited, unargued, and unnecessary to the Court’s holdings”). Accordingly, Naghani is not instructive, much less controlling.
Under the majority’s interpretation of Naghani, moreover, the enhancement would apply in virtually every ease of interfering with a flight attendant, rendering the distinction that the Guideline draws meaningless. The court there stated that “[i]f an actual emergency had .arisen at another part of the plane, the distraction [based on the defendant’s conduct] would have delayed, and perhaps prevented, an effective response by the flight attendants.” 5 Naghani, 361 F.3d at 1263. Under this logic, any interference with a flight attendant endangers the aircraft itself. If this were true, no enhancement would be necessary because the utmost punishment would be implied in the offense of conviction, as the majority seems to hold.6
*1043For this reason, the dicta in Naghani (and the majority’s reliance on it) is suspect because criminal liability and punishment may only be imposed when the operative language of the statute or Guideline at issue clearly dictates that result. See Rewis v. United States, 401 U.S. 808, 812, 91 S.Ct. 1056, 28 L.Ed.2d 493 (1971) (“[A]mbiguity concerning the ambit of criminal statutes should be resolved in favor of lenity.”); Bifulco v. United States, 447 U.S. 381, 387, 100 S.Ct. 2247, 65 L.Ed.2d 205 (1980) (“This policy of lenity means that the Court will not interpret a federal criminal statute so as to increase the penalty that it places on an individual when such an interpretation can be based on no more than a guess as to what Congress intended.”) (citations and quotation marks omitted). It is well-established that “one ‘is not to be subjected to a penalty unless the words of the statute plainly impose it.’ ” United States v. Campos-Serrano, 404 U.S. 293, 297, 92 S.Ct. 471, 30 L.Ed.2d 457 (1971) (emphasis added); see also United States v. Karaouni, 379 F.3d 1139, 1143 (9th Cir.2004) (same). Such is not the situation here.
Even if Naghani controls on this issue, the evidence presented in that case was sufficient to suggest that the aircraft was endangered, whereas it was not sufficient to establish such endangerment in this case. Where Naghani lit a cigarette, creating smoke, and then flushed the cigarette down the toilet, one could more reasonably conclude that the aircraft itself was endangered (by the danger of fire). See Naghani, 361 F.3d at 1258.
United States v. Guerrero, 193 F.Supp.2d 607 (E.D.N.Y.2002), similarly presented a case much more favorable to the application of the enhancement. In that case, the record disclosed:
Captain Williams testified that he had to leave the cockpit to deal with the defendant, when he learned from the flight attendant that she could not handle the situation herself. Captain Williams testified that this increased the risk to the safety of the aircraft, which is designed to be flown by two pilots. Defendant further endangered the aircraft and passengers when he pushed Captain Williams, because this exposed the aircraft and crew to the danger of having their captain incapacitated. Not only did Captain Williams testify that he thought defendant was making the flight unsafe, but his actions confirm that he believed that defendant was endangering the aircraft and passengers. Captain Williams testified that he only left the cockpit when he concluded there was a potential danger to the aircraft, and, upon returning to the cockpit, Captain Williams turned the aircraft around and returned to New York City because he concluded that it was unsafe to continue on to Santo Domingo.
Id. at 609-10.
United States v. Jenny, 7 F.3d 953 (10th Cir.1993), is also distinguishable because the captain left the cockpit to attend to the defendant’s inappropriate behavior. Id. at 955. Moreover, the court in Jenny was concerned with the definition of “reckless” and did not engage in defining the precise scope of what needed to be endangered in order for the enhancement to apply. See id. at 955-57. The facts also distinguish this case from United States v. Spellman, 243 F.Supp.2d 285 (E.D.Pa.2003), where *1044the pilot testified that there were additional risks and that there was “ ‘no tolerance for error’ ” in the landing that he was caused to execute due to the defendant’s inappropriate conduct. Id. at 288.7
All of the out-of-Circuit- cases relied on by the majority—Jenny, Guerrero, and Spellman—share a common characteristic that is lacking in this case. In all of them, the pilot left the flight deck—the cockpit— to confront the unruly passenger in the passenger compartment. Here, by contrast, the pilot did not leave the cockpit; Gonzalez did not interact with the flight crew at all. In this regard, it is important to note that the FAA regulations requiring that cockpit doors be reinforced to thwart a September 11-like unauthorized entry of a passenger into the cockpit were already in place well before the date of this incident. See Flightcrew Compartment Access and Door Designs, 67 Fed.Reg. 2112, 2114 (Jan. 15, 2002). As we know from the history of United Flight 93 on September 11, 2001, it is control of the cockpit that determines, to a large degree, the safety of the aircraft and it is in response to those events that the new regulations requiring the strengthening of flight deck doors and locks was promulgated.8 See id. In this case, control of the cockpit or safety of the flight crew was never endangered.
The majority speculates that the pilot’s flight routine was “seriously disrupted.” Maj. op. at 1037 n. 3. But, again, there is no evidence of how serious any disruption may have been and whether such disruption endangered the safety of the aircraft. Indeed, the majority’s concession that “it may well have been imprudent for the pilot to have left the cockpit under the circumstances,” id., is a virtual admission that, because the flight crew remained securely in the cockpit, the aircraft was not endangered.
*1045Gonzalez’s position is further strengthened by the fact that the cases the majority cites are not the only cases where circumstances favorable to the application of the enhancement have appeared. See, e.g., United States v. Vickaryous, 1996 WL 2773 at *1-*2 (10th Cir.1996) (applying enhancement under § 2A5.2(a)(2) where the defendant struck the pilot in the jaw, causing him to have severe difficulties performing his duties, including requiring assistance for an emergency landing); United States v. Bocook, 1995 WL 371250 (4th Cir.1995) (per curiam) (affirming enhancement under § 2A5.2(a)(1), dealing with intentional rather than reckless endangerment, where the defendant pretended to be an air traffic controller and gave false statements to pilots, including as they were attempting to land). Gonzalez’s situation was quite different from these cases, and I believe these distinctions should guide our decision here.
Even if one looks beyond the plain meaning of the Guideline, the history of this enhancement also supports Gonzalez’s position. Before 2002, as the majority mentions, the enhancement applied to reckless endangerment of “an aircraft and passengers.” See, e.g., U.S.S.G. § 2A5.2 (2001) (emphasis added). The deletion of the requirement that passengers be endangered, and the alteration of this enhancement to apply to “an airport or an aircraft,” show that this enhancement—at the time Gonzalez was sentenced—was geared solely towards punishing conduct that endangers objects, not people. See U.S.S.G. Supplement to Append. C, amend. 637, at 234. This change was accompanied by enhanced penalties for assault and other dangers to people that may attend these crimes. Given these other provisions, it is all the more clear that Gonzalez’s conduct did not come within the meaning of this enhancement. The overall penalties provided by the amendment were higher than before, moreover, so reading the enhancement according to its plain meaning seems quite consistent with Congress’ intent.9
*1046Because the aircraft-endangering enhancement should not apply if there is nothing more than interfering with flight attendants and potentially harming them and passengers, it was wrongfully applied in this case. Accordingly, I would vacate the sentence and remand this case to the district court. See, e.g., United States v. Kilby, 443 F.3d 1135, 1140 (9th Cir.2006) (“If there was material error in the Guidelines calculation, we will remand for resentencing....”); United States v. Menyweather, 431 F.3d 692, 696-97 (9th Cir.2005) (“[I]f the sentence imposed resulted from an incorrect application of the Sentencing Guidelines, and the error was not harmless, ordinarily we will remand to the district court for further sentencing proceedings, permitting the district court on remand to consider the proper Guidelines sentence along with other sentencing factors”).10
In sum, this case was simply a case of interfering with a flight attendant, and applying the enhancement under U.S.S.G. § 2A5.2(a)(2) here is tantamount to saying that it applies in virtually any case under 49 U.S.C. § 46504. The sentence imposed on Gonzalez was unreasonable because the district court miscalculated the applicable Guidelines range; consequently, I would reverse and remand for resentencing. For all of these reasons, I respectfully dissent.
. The majority concludes that "endangerment of the aircraft does not require evidence of actual harm to the aircraft.” Maj. op. at 1035 (emphasis in original). I do not dispute the majority's point that one can endanger an object without causing it actual harm. See Price v. United States Navy, 39 F.3d 1011, 1019 (9th Cir.1994); Ethyl Corp. v. EPA, 541 F.2d 1, 13 (D.C.Cir.1976). However, the object of the endangerment under U.S.S.G. § 2A5.2(a)(2) must still be the aircraft, meaning the machine involved, as opposed to the flight attendants, which was not shown in this case.
. The burden of proof is on the party seeking to adjust an offense level to establish by a preponderance of the evidence that the adjustment is merited. United States v. Charlesworth, 217 F.3d 1155, 1157-58 (9th Cir.2000); United States v. Barnes, 993 F.2d 680, 683 (9th Cir.1993). Having failed to make an adequate record at sentencing, as discussed below, the government clearly did not meet its burden here, contrary to the holding of the majority.
.The majority asserts that the "diversion of the aircraft and a return to Las Vegas" "was yet another risk to the aircraft caused by Gonzalez's escalating terror.” Maj. op. at 1038. But the majority does not explain how this decision and maneuver endangered the aircraft, unless returning to Las Vegas is, for some unexplained reason, more dangerous to aircraft safety than continuing on to Ontario, California. Absent a further explanation, and there is none in the record, the more reasonable inference would seem to be that, because this incident happened "[s]hortly after takeoff,” Maj. op. at 1032, the pilot concluded that it would be safer to return to Las Vegas, rather than to continue on to Ontario. In any *1042event, the majority’s weak retort that "such diversion was certainly not safer than the normal operation of the flight to Ontario,” id. at 1038 n. 4 (emphasis added), is a far cry from establishing that such “diversion” endangered the aircraft.
.Even if the government were correct that a threat alone can endanger the safety of an aircraft (i.e., without any weapon or bomb needing to be present), one would still need a causal connection between the threat and actual endangerment—to the mechanics or structure of an aircraft—before the enhancement could apply. The district court did not make any factual findings about endangerment to the aircraft, and the only testimony from flight attendants indicated fear for themselves and passengers on the plane, and the passengers’ fear about the emergency exit door being opened. Notably, the feared opening of the emergency exit door was shown to be a nullity because there was testimony at the sentencing hearing that it is impossible to open a door in flight.
. It would be pointless to speculate what sort of "actual emergency” a flight attendant would be responsible for responding to, except to note that a flight attendant has no responsibility for tire safe operation of the aircraft. That is the responsibility of the flight deck crew.
. To the contrary, to date, it appears to have been undisputed that endangering the safety of an aircraft was not an element of a violation of 49 U.S.C. § 46504. To this end, it is important to note that the actual language of 49 U.S.C. § 46504, governing "interference with flight crew members and attendants,” covers "lessening] the ability of the member or attendant to peiform ” his or her duties. 49 U.S.C. § 46504 (emphasis added). Clearly, the statute thereby takes into account the lessening of a flight attendant’s ability to' ensure the safety of the aircraft. See United States v. Meeker, 527 F.2d 12, 14 n. 2 (9th Cir.1975) ("We feel ... that when a defendant participates in proscribed conduct and causes a crew member to lose his autonomy over do*1043ing what would ordinarily be his duty, a violation of section 1472(j) has occurred.”); United States v. Flores, 968 F.2d 1366, 1371 (1st Cir.1992); United States v. Tabacca, 924 F.2d 906, 911 (9th Cir.1991). Accordingly, Nagha-ni’s dicta is itself contrary to previous decisions of this court, insofar as it read the satisfaction of the elements of 49 U.S.C. § 46504 itself as warranting the enhancement.
. The majority relies on these cases to state that "diversion of the aircraft, behavior that instills fear and terror in the other passengers or the flight crew, and threats that could result in harm to the aircraft are sufficient, depending on the combination of circumstances, to constitute reckless endangerment of the safety of the aircraft.’' Maj. op. at 1037-38. However, there is no evidence in this case that diversion of the aircraft endangered the aircraft, and making passengers (and even the flight crew) fearful and empty threats that cannot be carried out can scarcely be said to endanger the aircraft any more than interference with flight attendants alone does, under 49 U.S.C. § 46504. Tellingly, the majority immediately acknowledges that "simply disrupting the flight attendants and causing other passengers discomfort does not rise to the level of reckless endangerment." Maj. op. at 1038. What the majority fails to acknowledge, and a reason I dissent, is that this is the only kind of finding the evidence here supports.
. Because Gonzalez did not interact with the flight crew, the question of whether his conduct could have been properly construed as reckless is also an open one, because there is no indication that he "was aware of the risk created by his conduct” to the aircraft. See Naghani, 361 F.3d at 1263 (applying definition of reckless from U.S.S.G. § 2A1.4 to § 2A5.2); U.S.S.G. § 2A1.4, Application Note 1. Notably, too, the government could easily have attempted to meet its burden by presenting the testimony of the pilot that his performance was affected or that he believed the aircraft was in danger, or any other evidence that the aircraft was endangered. The government failed to do so. Thus, the majority's statements about Gonzalez’s general recklessness, Maj. op. at 1038-39, are inapposite because any such recklessness did not endanger the safety of the aircraft. The majority also states that "[i]t doesn’t take an aeronautical engineer to recognize that a threat of a bomb in [an aircraft] environment and the havoc that such a threat might cause is a threat to the safety of the aircraft.” Maj. op. at 1038 (emphasis added). Although I fail to follow the logic of this assertion, its emphasis on "might cause” renders the speculation superfluous. Significantly, the actualization of such potential is what should have been proven in order to prove endangerment to the safety of the aircraft. It was not.
. The commentary to the 2002 amendment recognized concern that the base offense level provided in U.S.S.G. § 2A5.2(a)(2) was inadequate in situations involving a dangerous weapon and reckless disregard for the safety of human life. See U.S.S.G. Supplement to Append. C, amend. 637, at 247. To sanction conduct involving mortal peril, accordingly, the Sentencing Commission supplemented the Guideline to provide for a minimum offense level of 24. See id.; U.S.S.G. § 2A5.2(b)(1) (2002). The commentary also indicated that the Commission was becoming more concerned with threats to mass transportation systems and facilities, see U.S.S.G. Supplement to Append. C, amend. 637, at 247, which is consistent with my reading of the Guideline.
Moreover, the previous iteration of the Guideline shows that the Sentencing Commission clearly understood aircraft and flight attendant/passenger safety as distinct concepts. This fact further supports Gonzalez's claim that the meaning of "aircraft” is unambiguous and does not include flight attendants and passengers. See U.S.S.G. Supplement to Append. C, amend. 637, at 234. Moreover, as Gonzalez suggests, the structure of U.S.S.G. § 2A5.2—even disregarding the fact of the amendment—intimates that the Guideline does not equate endangering a flight attendant with endangering the aircraft, because it provides a separate cross-reference to assault Guidelines when resort to assault Guidelines would result in a higher base offense level. See U.S.S.G. § 2A5.2(a)(3).
Thus, the majority misreads the effects of the amendments, and misapplies their implications to this case. See Maj. op. at 1035. That is, the majority writes that "it is now easier to invoke the sentence enhancements because § 2A5.2(a)(2) does not require a showing of endangerment to the passengers.” Maj. op. at 1035 (emphasis in original). However, endangerment of passengers is not relevant in this case. The question here is endangerment of the safety of the aircraft. The majority also misunderstands the enhancement when it states, as an example, that "even if an individual threatened to blow up an empty aircraft, he could receive an enhancement under § 2A5.2(a)(2).” This should not be the case, because a threat to *1046blow up an aircraft does not endanger the aircraft. Even if, moreover, “in the case of an aircraft loaded with passengers, Congress reasonably assumed, as would most people, that endangering an aircraft would endanger the passengers,” that is not what the Guideline references. Congress referred to endangerment of the aircraft as what was required, and whether or not Congress intended to protect passengers through the application of this enhancement, Congress did not use language that referred to passengers in its test.
. Even if the enhancement could have applied to Gonzalez, he was surely prejudiced because the enhancement was not proven by clear and convincing evidence—to which end I note the glaring absence of any testimony about danger to the safety of the aircraft. See, e.g., United States v. Jordan, 256 F.3d 922, 930 (9th Cir.2001) ("[I]t is evident beyond doubt that Jordan's increased incarceration caused by the challenged enhancements is prejudicial if these enhancements could not have been proved by clear and convincing evidence.”). Gonzalez also convincingly argues that it is possible that the district court based its finding on a belief that Gonzalez recklessly endangered only the flight attendants and/or passengers. The government made an argument that could be read to this effect, namely when it said that it was "first addressing the issue whether or not the defendant was—had recklessly endangered other passengersf] lives on the airplane." There is nothing in the record to indicate that the district court did not share the same misapprehension of the Guideline, particularly in light of its failure to make any findings on this issue, and this fact also counsels in favor of remand.