Virgil Wiebe's Aug. 3 letter, "Duds Keep on Killing," is somewhat misleading in its assertion that the dud rates of cluster bombs were as high as 30 percent during the Vietnam War and 20 percent during the Persian Gulf War. The very nature of cluster bomb units makes a precise figure impossible. Estimates depend on the experience and judgment of witnesses -- usually the pilots involved.

When I was a forward air controller in Southeast Asia, I observed about 1,500 sorties of fighters -- of which about 85 percent delivered cluster bomb units in some form. I would estimate that about 10 percent of the bomblets did not detonate. Contrary to Mr. Wiebe's pejorative language, only a tiny percentage of the cluster bomb units used in Southeast Asia fell into the category of "mines," and these were supposed to self-destruct after 28 days (although some undoubtedly did not). Commentary on weapons use and dud rates should be influenced by some firsthand experience.

Bomblets then were olive drab in color. They are now, apparently, yellow -- a cautionary color in most cultures. This makes detection and removal of duds far easier. Cluster bombs, used appropriately, are a superb force-multiplier weapon in situations involving massed troops, armor, support facilities and anti-aircraft installations. Perhaps Mr. Wiebe would prefer a return to the good old days of mass dumps of 500-pound bombs -- which dud at a similar rate.

KARL POLIFKA

Williamsburg

The writer is a retired Air Force colonel.