Delta Air Lines‘ top brass apparently feels a bit self-conscious about reporting executive pay today in a statement to the SEC.

Delta’s CEO and president took the unusual step Wednesday of sending a memo to employees warning them they might see some really big numbers in the days ahead and explaining that it’s not as much as it might seem.

CEO Richard Anderson said his 2008  pay was $2.5 million. President Ed Bastian put his 2008 pay at $5.2 million. Based on data from PayScale.com, that’s about 130 times more than the median pay for a Delta flight attendant or customer service representative.

But look at it this way, as the letter to employees suggests: “Compared to the results of an April 2, 2009 survey published in the Wall Street Journal, our ongoing compensation is in the bottom third of U.S. corporations our size.”

The executives said their base pay did not change last year. “Like all employees, we received special awards of stock” from the company’s bankruptcy emergence and merger with Northwest Airlines. And they promised no raises for themselves this year either.

“You have our commitment that we will never lose sight of the importance of continuing to invest in Delta people — in you.”