The U.S. aircraft register, updated daily
Engines · piston (reciprocating) · data as of October 5, 2026

Lycoming HIO-390-X252

2 aircraft on the U.S. register carry a Lycoming HIO-390-X252 engine, rated at about 210 horsepower. The Enstrom Helicopter Corp TH-180 is the model most often fitted with it (2 aircraft). The aircraft carrying it were built between 2016 and 2017.

The FAA records engines by code, usually at the level of a series ("O-320 series") rather than the exact variant; this page gathers every FAA code that reads as Lycoming HIO-390-X252. FAA spelling: HIO-390-X252.

Fitted to model families

Enstrom Helicopter Corp TH-1802

Enstrom Helicopter Corp TH-180

Where they are owner's state

Michigan2

Kind of aircraft

Helicopters2 (100%)

When the aircraft were built by decade

0012222010

What the FAA has certified, ordered and been told about the Lycoming HIO-390-X252 the component layer

The design is held under 1 type certificate (E00006NY, held by Lycoming Engines). The FAA has issued 2 airworthiness directives (orders that owners must comply with) that name this engine series.

FAA orders 2 airworthiness directives · newest first

2026-04-082026-04-11 · Engine (Reciprocating) · engine
2024-12-052024-21-02 · Engine (Reciprocating) · engine

Certificates and bulletins

E00006NYType certificate held by Lycoming Engines · 17 models listed · revised January 12, 2023

Safety bulletins 1 · advice, not orders

2019-05-02NE-19-08 · Reciprocating Engine Cylinder Section - Lycoming Engines Parallel Valve Cylinders

Sources: the FAA's type certificate data sheets, airworthiness directives, supplemental type certificates, special conditions and special airworthiness information bulletins (Dynamic Regulatory System), and the FAA's service difficulty reports. A failure report is what an operator or repair station chose to file; the counts show reporting as much as reliability, and larger and commercial fleets report more. How the systems are grouped.

Connections how this engine series links to the rest of the register

Where they are
Biggest operators
Airworthiness

These connections as data: /graph/engine/lycoming-hio-390-x252.json · about the eFlight graph.

Aircraft newest certificates first · 2

Tail no.Maker and modelGroupOwner and baseCertificateRegisteredStatus
N181TH Enstrom Helicopter Corp
TH-180
Rotorcraft Enstrom Helicopter CORP
Menominee, Michigan
Experimental 2022-12-14 ValidFAA registration status code V: Valid registration. All codes
N180TH Enstrom Helicopter Corp
TH-180
Rotorcraft Enstrom Helicopter CORP
Menominee, Michigan
Experimental 2022-12-05 ValidFAA registration status code V: Valid registration. All codes

Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 5, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.