06/30/2009. Remarks by Johan Visschedijk: "This experimental aircraft was produced to investigate the combination of Mach 2+ performance with STOL capability. Powered by a 11,464 lb (5,200 kg) st (17,196 lb, 7,800 kg with afterburner) Khachaturov
R-27-300 turbofan engine, the MiG-23PD (PD = pod'yomnye dvigateli, lifting engines) also had two 5,180 lb (2,350 kg) Kolesov RD-36-35 engines mounted mid-fuselage at 85º.
The aircraft was first flown by Piotr M. Ostapyenko on April 3, 1967, after an impressive public appearance at the Domodyedove Air Show on July 9, 1967, the aircraft reportedly did not fly again. The aircraft has also been seen designated E-23, E-23DPD, E-231, MiG-23PD, and Ye-230."