Originally posted by Ack-Ack
The Mossie had a low radar signature, lower than the Spitfire due to it's wooden construction. Some even consider it the first "stealth" plane.
ack-ack
To the best of my knowledge, the claim that the Mosquito had a smaller radar signature than the Spitfire is anecdotal, rather than factual. It is most likely based on an incomplete understanding of radar and radar signatures. Depending on the wavelength and aspect (the direction the radar beam intersects the target from) the Mossie quite possibly had a significantly larger radar cross-section (RCS) than a Spitfire. While the skin and frame were wood (which has a lower reflectivity than metal, but not zero reflectivity), that simply means that all the “ugly” reflectors inside the skin – such as engines, fuel tanks, fuel and hydraulic lines, wires, control cables, guns, ammo, armor plate to name but a few – are all visible to the radar, and contribute to the RCS. Instead of getting a rather sizable but narrow specular return from the skin, all those individual reflectors inside the skin add together. The result is a radar return that is somewhat lower in amplitude in some directions, but is on average nearly just as large.
Did the Mosquito have a lower RCS than a metal-skinned aircraft of comparable size? Probably. Smaller than a Spitfire? I’ve been unable to locate any actual RCS measurements of both to compare them, but my professional opinion is that it is unlikely. Without going into details, my thesis was, shall we say, related to the topic.
On a historical note, the Mossie’s unusual construction had nothing to due with RCS reduction (an as yet little considered question in 1938). Rather it was a brilliant idea to tap into an under-utilized segment of the workforce, using non-strategic materials, to construct very fast and light combat plane. The RAF didn’t want anything to do with the project…until De Havilland showed them the specs on the Mosquito.
If I ever get to another AH Con, and there is sufficient interest, I would happily host a discussion on radar and RCS measurement and reduction (a.k.a. "stealth").