It's certainly got that first-generation prototype look about it. Square or rectangular fins with straight leading edges, awkward and un-aerodynamic noses for the heat-sniffers and simple cones & ogives for the radar-homers and beam-riders. There's no mistaking a missile born in the late 40s or early 50s.
Looking at it then you wouldn't imagine that it would go on to be one of the most distinctive and well known missiles ever produced and still in use in the 21st century. You can also see quite clearly the distinctive rollerons.
It was based on the 5" HVAR unguided rocket engine, and is clearly a prototype. Its genius was its simplicity - where others were trying to make miniature airplanes, Sidewinder was the minimum smarts needed to make an unguided rocket guided.
Eugene Fleeman's "Tactical Missile Design" (2nd Edition) describes this canted arrangement as "interdigitated" (versus "in-line"). He states: "Interdigitated surfaces may have advantages of less induced roll and launch platform compatibility. However, inline surfaces are usually preferred because of lower drag and RCS."
It may be that they had them interdigitated to start with because they anticipated the induced-roll issue, but found that the rollerons controlled it sufficiently well that they could go to an in-line profile in subsequent iterations of the design. Reading books published in the time these missiles were being developed or first introduced can be both fascinating and frustrating - fascinating because a lot of the aerodynamics was truly ground-breaking; frustrating because they are naturally precluded from giving too many specifics about the actual missiles to which the aerodynamics applied. My only hope is that some of these records are still intact when the Official Secrets Act or its equivalent finally expires on them.
It seems to me that if they'd settled on the interdigitated profile, the launchers would have been configured to suit. This was the first generation, remember (perhaps even the "zeroth") - back-compatibility with previous models of the same missile would not have been an issue.
I could accept that a shift to an in-line profile might have made it easier for the rack designer to interface the various plug-ins with the missile internals, and the longer rack which the in-line profile allows might offer a more secure carry and stable launch, but it seems a little bit cart-before-horse to shape the missile's entire aerodynamic profile (and possibly more) around the launcher in this particular case. [/size]OTOH, A Sidewinder successor or competitor that was launched into an existing market, and constrained to use the same launcher, would be another matter.[size=78%]
The China Lake folks are very proud of inventing and developing Sidewinder. As a consequence of that they have an excellent historical record at the museum on base.
chinalakemuseum.org. It is well worth a visit if you get to the Mojave Desert - you can also check out Edwards while you are in the area.
Came across this homemade video about the rolleron, an innovation more or less unique to the pre-X variant Sidewinder (and Vympel K-13 /AA-2 "Atoll" copy). This is the first detail practical demonstration of how the rolleron works I've seen, and it's pretty neat.
I was spurred to look for more about the rolleron after seeing this raw footage of a couple VF-211 North American FJ-3 Fury aircraft being towed about USS Bon Homme Richard (CV-31) in June 1956. I don't know if the Sidewinder partially shown in detail has slab tail fins because it is a training article, or because that bit of technology was still classified at the time.