The Serpent's Lair (3) - S2-E1
Corrected entry: Lt. Col. Samuels claims that the missiles they plan to launch against the Goa'uld ships are made of the same material as Stealth aircraft and should therefore be invisible to radar. The missiles however, unlike Stealth fighters, have jet engines which are visible to the naked eye, thus negating the Stealth technology.
Correction: The visibility of the propulsion does not negate the fact that the missiles are made of the same material as stealth aircraft and that they are invisible to RADAR. They are hoping that there are no Jaffa looking out of the Hatak windows.