Messages created by planes

• Message made by pilots
• Writing formed in the sky by smoke released from an airplane
• Message from heaven?

Wikipedia Word definitions in Wikipedia
'''Skywriting ''' is the process of using a small aircraft , able to expel special smoke during flight, to fly in certain patterns that create writing readable by someone on the ground. The message is often a frivolous phrase, a generally meaningless greeting, ...

Wiktionary Word definitions in Wiktionary
n. Messages, left by leaving a trail of smoke from an airplane, that are visible from the ground.

WordNet Word definitions in WordNet
n. writing formed in the sky by smoke released from an airplane