Is AD 2011-27687 a recurring Airworthiness Directive?

No — AD 2011-27687 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2011-27687 apply to?

AD 2011-27687 applies to Bell — models 407, 427. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2011-27687

one-time

AD 2011-27687 · 2011-10-27 · airframe

Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Model 407 and 427 Helicopters

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2011-15-51, which was sent previously to all known U.S. owners and operators of the specified Bell Model 407 and 427 helicopters by individual letters. This AD requires inspecting certain hydraulic servo actuators to determine whether the shaft turns independently of the nut or the clevis assembly. If the shaft turns independently, this AD requires replacing the servo with an airworthy servo. If the shaft does not turn independently, the AD requires inspecting to determine the condition of the lock washers. Based on the condition of the lock washers, the AD requires either replacing the servo with an airworthy servo, or if any tab of the lock washer is not flush against a flat surface of the nut or clevis assembly, bending it flush against a flat surface. The AD also requires reidentifying the servo by metal-impression stamping or by vibro- etching "67.01" onto the modification plate. Also, the AD requires before installing a servo with a part number or serial number identified in this AD, not identified by "67-01" on the modification plate, inspecting it by following the requirements of this AD. This AD is prompted by a report that a quality escape by a supplier has occurred and certain servos may have a loose nut, shaft, and clevis assembly due to improper lock-washer installation. An investigation after an accident revealed the clevis nut on the servo was loose. The actions specified by this AD are intended to prevent a malfunction of a servo in the flight control system and subsequent loss of control of the helicopter.

Which aircraft AD 2011-27687 applies to

MakesBell

Models407, 427

Part-conditional — 206-076-062-105, 206-076-062-107, 206-076-062-109, 206-076-062-111.

Model 407 helicopters with hydraulic servo actuator P/N 206-076-062-105 or -107 installed; Model 427 helicopters with servo actuator P/N 206-076-062-109 or -111 installed.

Whether AD 2011-27687 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

How AD compliance is recorded

A valid compliance record (14 CFR 43.9) states:

Method of compliance — The specific action taken (inspected, replaced, modified) and to what revision.

Date — When the work was done.

Aircraft time — Total time in service / tach at compliance — how recurring next-due is computed.

Signature & certificate — The A&P/IA who returned it to service, with certificate number.

Is AD 2011-27687 complied with on your aircraft?

Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.

Look up a tail number →Read the full directive (Federal Register)

Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.