Investors that are familiar with airline equities are inevitably familiar with how oil prices affect those stocks. After all, fuel and labor are the two biggest input costs for airlines and last year’s 42.4% swoon for the United States Oil Fund (NYSEArca: USO) explains why airline stocks were among Wall Street’s darlings in 2014.

Oil prices have recently rallied with USO up nearly 5% for the 90 days ended May 8, but that does not necessarily spell trouble for some of the holdings of the newly minted U.S. Global Jets ETF (NYSEArca: JETS). In a Cowen note posted by Ben Levisohn of Barron’s, the research firm had this to say about American Airlines (NYSE: AAL):

American forecasts 2Q15 pre-tax margin of 17% to 19%, down from their prior estimate of 18% to 20%. The reduction in guidance is based on higher than expected jet fuel costs. Jet fuel has bounced off the bottom since initial guidance and is now forecast to be ~10 cents higher per gallon than initially expected in 2Q15. Management forecasts 2Q15 jet fuel of $1.94 to $1.99/gallon, up from prior guidance of $1.84 to $1.89/gallon previously. American shares have lagged the XAL index in 2Q, down 7.1% vs the XAL up 0.3%. We believe higher jet fuel costs are already baked into the shares given the performance quarter to date. Management reiterated their 2Q15 PRASM range of down 4% to 6%.”

American ties with rival United Continental (NYSE: UAL) as the third-largest holding in JETFs at a weight of 11.17%. With a year-to-date loss of 7.7%, Texas-based American is the worst performer among JETS’ four largest holdings, though it should be noted that only Southwest (NYSE: LUV) has traded to the upside this year. [Why the new Airline ETF Could be a Success]

Predictably, JETS has shown some sensitivity, though positive to this point, to oil prices. Granted, the sample size is small, but since JETS debuted on April 30, USO is off 0.7%, but the airline ETF is higher by almost 3.5%. Delta (NYSE: DAL), Southwest and United Continental are all up more than 5% since JETFs came to market while American is higher by almost 3%. That quartet combines for 46% of the new ETF’s weight. [A new ETF for an Inexpensive Industry]