"The two midwave IR sensors—mounted in a nose pod on the WB-57 and internally on the P-3—were about 60 nm from the rocket when it reignited its engines for supe

"The two midwave IR sensors—mounted in a nose pod on the WB-57 and internally on the P-3—were about 60 nm from the rocket when it reignited its engines for supersonic retropropulsion." They clearly mean Nautical Miles (nm) here, but I did a double-take on my first read through.