Ordinary refers to an "ordinary expense" as define in IRS Publication 463.  Ordinary is one of the tests that must be passed in order for an employee business expense or travel expense to be tax deductible.  IRS Publication 463 defines and ordinary expense as one that is:

common and accepted in your field of trade, business, or profession.

For airline pilot taxes and flight attendant taxes, that mean an expense is considered ordinary if is common and accepted in the airline industry.  The following list could be considered ordinary expenses within the aviation field, yet they still may not be tax deductible until other tests are passed.

• A cell phone bill (see article: May be partly deductible but limited by Test 3)

• A wristwatch (see article: Not deductible because of Test 4)

• A laminated aviation map (see article: probably deductible)

• A car (see article: not deductible because it fails Test 3 and Test 4)

• A computer (see article: generally not deductible because of Test 3 and Test 4)

• Internet fees (see article: May be partly deductible but limited by Test 3)

• Socks (see article: not deductible because of Test 3)

• iPod (see article: not deductible because of Test 2 and Test 3)

The links in the list above link to an EZPERDIEM.COM Article that details the methodology in determining whether or not an airline-related employee business expense is tax deductible.  Furthermore, the EZPERDIEM.COM Expense Processor^TM makes it simple to calculate flight crew tax deductions for a given tax year.

 

See also, necessary expense and personal expense.