There is an issue, and since aircraft are energy hungry, it is worth keeping a watch on development of alternative fuels, and alternative power sources.
M. King Hubbert, an oil man predicted that availability of oil would peak around the year 2000, with a decline after that.
It was a remarkable prediction:
M. King Hubbert • Hubbert Peak of Oil Production
Dr Colin Campell's explanation on 4 Corners is as good as I've seen. he points out that what we are facing is the long decline, with some ups and downs in pricing, but an inevitable long term result if we just use traditional oil products.
4 Corners Broadband: Peak Oil?