I have found the following: Letter from 27 pilots - transcript of interview session
Here is a excerpted quote from the interview:
CONAN: Now some members of the armed forces have also signed statements refusing to serve in Palestinian territories.
GRADSTEIN: Yes. Close to 600 of them, both active duty and reserve personnel, have said that they will not serve in the territories, and probably hundreds of others have quietly asked to be transferred. The most public of this was a letter signed by 27 former and reserve pilots in September saying that they would no longer fly missions attacking Palestinian militants in assassination attempts and air strikes in which Palestinian civilians are also often killed.
Israeli officials say it's collateral damage, they say they're not aiming for these people. But these pilots said that they would not fly these missions anymore. And the pilots are really the elite in the Israeli armed forces, and it caused a huge stir here and a huge controversy over whether it was appropriate or not for them to say that.
The source is Talk of the Nation, Neal Conan in Washington speaking with Linda Gradstein of NPR.
Is this what you were refering to?