IATA S58ICAO S58T

Sikorsky S-58T

Sikorsky

TravelerPulse profile

Twin-turbine conversion of the classic S-58 piston helicopter.

First flight

1970

Category

Utility helicopter

Seating

12–16

Range

402 km

Engines

Two Pratt & Whitney Canada PT6T-3 turboshaft engines (Twin Pac), coupled

Status

In service

The Sikorsky S-58T is a turbine-powered conversion of the original piston-engined Sikorsky S-58 helicopter, which first flew in 1954. The conversion replaces the original Wright R-1820 radial piston engine with a coupled pair of Pratt & Whitney Canada PT6T-3 Twin Pac turboshaft engines, significantly improving performance, reliability, and payload capacity. The conversion program was developed by Sikorsky and later managed by other companies, allowing operators to upgrade existing S-58 airframes to turbine power at lower cost than purchasing new helicopters. The S-58T found use in utility, offshore oil support, logging, firefighting, and passenger operations around the world. Numerous S-58T conversions remain in service with various commercial and government operators globally, particularly in regions where the robust and capable platform continues to fulfill demanding roles.

Notable operators

Operators have included various offshore oil support, utility, and regional passenger carriers in Southeast Asia, Latin America, and elsewhere, including Petroleum Helicopters and Era Aviation.

Notable facts

›Converted from the piston-powered Sikorsky S-58, which first flew in 1954.
›Uses the Pratt & Whitney Canada PT6T-3 Twin Pac, combining two turboshaft engines.
›Conversion substantially increased payload and hot-and-high performance over the original.
›Carson Helicopters was a major operator and operator of conversion programs.
›The airframe's ruggedness made the S-58T popular for logging and heavy-lift utility work.