The Pentagon is studying ways to replace the almost worn-out EA-6B Prowler airborne jammer aircraft. The Navy wanted to build an F-18G "Growler" which would do the same job, but it would cost $1 billion to develop and then $100 million per aircraft, and would not quite be as effective as simply building more EA-6Bs (which would cost less on a per each basis and require no development). --Stephen V Cole