Detection of enemy plane by condensation trail?

[Yongpeng Sun-Tastaufen]

Currently, no nuclear engine. Internal combustion engine. Puts lots of water vapor byproduct into the air behind the plane. At low temperature up there, condense into massive condensation trail. Radar signature about 3 m^2 at least. Easily picked up by enemy plane radar no? If you don't want condensation trail, then don't put water vapor into the air, so don't do internal combustion, needs nuclear engine which power turbine by nuclear power, no water vapor, no condensation.