Average VLookup over multiple sheets

Hello All-

I am new to the forum & excel but hopefully someone can assist.

I am trying to find average times by using VLOOKUP (or a better function) on a workbook of data which contains 31 separate tabs (1 for each day of the month)

My data is a list a flights and associated times with each flight.

I've attached an example.
**Please note, the example includes only 5 tabs (5 dates), while the true data set has 31 tabs. Also, not all flights operate everyday and the order of flights can change each day.

Thanks for any assistance,
Peter