During the early-to-mid 1950s the USAF was evaluating German aerospace technology and this led to various US aircraft companies exploring German jet configurations for a high altitude recon bird as the Cold War heated up. By the mid-'50s, Bell was exploring Dornberger's HSHA (High Speed- High Altitude) designs and also Dr. Lippisch's delta wings. The result was the 1956 proposal of Bell's WS-118P (aka SR-12). This was a very long fuselage with mated delta wings which carried twinned ramjets on each wing. The aircraft was designed for Mach 3.2 cruise at high altitude (above 80,000 ft)! The design was wind-tunnel tested and a scale glider was made to test the basic design. But the metals needed for KE friction at the time were scarce and there were flaws with the engine configuration that could lead to flat-spin catastrophe if one or more of the engines flamed out. Vibration was also a severe problem as was ejection tech at such altitudes. Rockwell also proposed a rival but reached the same conclusions. Many SR designs were considered until the SR-71 arrived in the 1960s with some limited stealth, use of titanium, working turborams, and sophisticated navigations sytems that were integrated. The WS-118P (Weapon System 118 Papa) design had no chance to be built when it was proposed.

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