Brief Answer:
You can travel by flight with black eye.

Detailed Answer:
Hello
Welcome to Health care magic

I am Dr. DADAPEER K, an Ophthalmologist and I answer health problems related to eye.

I reviewed your history.
Black eye is caused by collection of blood in the layers of eye lids. The most common cause for this is injury.
If you are not having any other problem of the eye other than black eye then you can travel by flight.

Hope I have answered your question and the information is helpful to you.
Do write back to me for further questions.

Thank you

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