Compressed natural gas (CNG) has several things going for it. It is cheaper than gasoline or diesel fuel, has lower emissions, and for a conventional piston-engined airplane, is the equivalent of over 130 octane, far more powerful than 100-octane low lead (100LL) and cleaner burning. CNG Fuels in England CNG filling stations are growing across the country as fleet owners take advantage of the economics of converting their vehicles, but are still few and far between in the west, with the exception of California. There are under 900 stations throughout America. Alluring as CNG might be for drivers, pilots used to paying $5.50 per gallon for avgas should be charmed by CNG’s price of $1.00 per gallon equivalent. That is with conventional, fossil-based CNG, basically a storable version of natural gas. That leads to its less-desirable characteristics. First, it pollutes, too, and is a source of greenhouse gases. Second, natural gas has a hard time overcoming its association with fracking, …