Ammonia stays close to the ground, besides if as much ammonia leaks out as the amount of hydrogen that was on the Hindenburg I can see another disaster similar to the Union Carbide chemical accident in India a few years back. 2% hydrazine was used as a fuel booster in nitromethane back in the sixties, large power gains were noted, From engine blow ups and anybody that was near the stuff developing all kinds of cancers, people learned to leave it alone. AMMONIA IS DANGEROUS. One lung full and you are screwed