N458AC

This article describes a specific airframe registered as N458AC, a Sikorsky-built rotorcraft in the S-58ET configuration bearing manufacturer serial number 581662. The airframe is recorded in company ownership under Helicopter Transport Services and has been presented in registry records as a US-registered helicopter. No public build year or prior owner sequence is published for this tail number in the supplied data. Condition notes and market valuation figures for this individual airframe were not provided.

The airframe is configured with a utility, configurable passenger–cargo cabin typical of S-58T conversions, accommodating approximately 10–14 passengers in common layouts. Operators using this conversion typically employ the cabin for mixed roles—passenger transport, cargo lifts and utility missions—taking advantage of the S-58ET’s adaptable interior. Avionics specifics for N458AC are not published in the supplied data; maintenance considerations center on the Twin-Pac powerplant installation, which requires attention to both components of the PT6T package and associated drive systems. Based on the operator name Helicopter Transport Services, routine operations are likely oriented toward commercial utility and charter roles out of its US registry, though a definitive home base or route structure is not provided.

The Sikorsky S-58ET is a legacy piston-to-turbine conversion line that occupies a niche for rugged medium-lift rotorcraft with flexible cabin arrangements. With the Twin-Pac PT6T installation delivering moderate shaft output and a cruise of roughly 100 kts, the S-58ET competes with other medium utility helicopters in secondary markets and charter operations. Buyer and charter demand for airframes like N458AC is influenced by airframe condition, availability of spare parts for legacy Sikorsky systems, and the health of PT6T support; resale considerations commonly emphasize engine life, structural corrosion inspection results, and the completeness of conversion documentation.