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The giant dragon keenly perceived Richard's malicious intent, quickly swinging its tail to block Richard's view.
Richard had no choice but to look at the airspace behind where the giant dragon had flown, then noticed there was no contrail.
This was a bit peculiar.
Generally speaking, when a jet engine plane travels through the air, the engine sprays high-temperature gases laden with water vapor backward. If the surrounding temperature is relatively low, these hot and humid gases rapidly mix with the surrounding air, quickly cooling and abruptly increasing in humidity. Coupled with the expelled particulate matter, it quickly condenses to form an aircraft contrail, colloquially known as a contrail line.
But this phenomenon was absent with the giant dragon, perhaps because the surrounding temperature wasn't low enough, or maybe... it was flying by some unknown third method, such as... magic.
