In Sudan, while spraying in a Piper Pawnee, I had a scary encounter. We were spraying against locusts and flew 2m about the crop, which was 3-4' tall. Each field required about 6 strips i.e passes, to cover it. Locusts are the pet food for a sparrow like bird, but I didn't know that. I dropped down to spray height, 90kts, on the first pass and a huge carpet, nearly the size if the field, lifted off right in front of me. It was swarm of these birds. The engine cowling was nearly full of flesh & feathers, the leading edges were blasted with blood & guts and the trailing edges between the spray booms were full of bodies. The BBQ smell was nauseating and I had to break off and return to base, about 10 mins flying. Fortunate the cockpit windscreen remained intact, but the eyebrow air vent was clogged with detritus.
We called off that field for the day, and in future and ground guys go out to 'beat' the fields. They too had to be careful as some years before a local guys and been out in the crop, doing whatever, and had not listened to the chief's warning not to venture into that field. he heard the a/c, wondered WTF, stood up and lost his head.
Strong a/c the Pawnee.