Follows In-Flight Failure Of Simplex Model 244 Spray System

The FAA is proposing an Airworthiness Directive for Robinson Helicopter Company Model R44 and R44 II helicopters with an agricultural spray system installed by Supplemental Type Certificate (STC) SR00286BO (spray system). This spray system is also known as a Simplex Manufacturing Company (Simplex) Model 244 spray system. This proposed AD was prompted by a report of an in-flight failure of the spray system elbow pump fitting (pump fitting). This proposed AD would require repetitive inspections of the spray system pump fitting, corrective action if necessary, replacement of the spray system pump fitting, and installation of hose supports and a pump outlet cover.

According to the proposed AD posted to the Federal Register, the action is prompted by a report of an in-flight failure of the spray system pump fitting. Following the issuance of a Simplex service letter, five additional reports of failed fittings were received. Failure of the pump fitting causes uncontrolled discharge of the spray liquid exiting the system pump. The pump output port is in direct alignment with the engine air intake, allowing the engine to ingest the spray liquid. This condition, if not addressed, could result in an in-flight engine shutdown.

The AD would require, before each flight, visually inspecting the spray system pump fitting for signs of stress, cracking, fatigue, and evidence of leaking. If there is any sign of stress, cracking, fatigue, or evidence of leaking, this proposed AD would require replacing pump fitting P/N P-58-0752-40 with pump fitting P/N 000-123847-000, and installing cushion clamp P/N 000-115571-000, cable tie hose supports, and pump outlet cover P/N 244-302056-001 before further flight. If there is no sign of stress, cracking, fatigue, or evidence of leaking, this proposed AD would require replacing the pump fitting with fitting P/N 000-123847-000, and installing cushion clamp P/N 000-115571-000, cable tie hose supports, and pump outlet cover P/N 244-302056-001 within 3 months. This proposed AD would also require pressurizing and inspecting the spray system with fitting P/N 000-123847-000, the cushion clamp, the cable tie hose supports, and the pump outlet cover installed, and depending on the outcome of this inspection, replacing the parts and repeating the inspection again.

The proposed AD is open for public comments through January 31, 2020.

(Image from file)

FMI: Federal Register