From Multi-Engine Turboprop Communiqué # ME-TP-007

From Multi-Engine Turboprop Communiqué # ME-TP-007

Date: January 2018

ATA 23 – Cockpit Voice Recorder (CVR) and Flight Data Recorder (FDR) 90-Day Underwater Locator Beacon (ULB)

In 2015, the FAA revised Technical Standard Order (TSO) C121a for ULBs. TSO C121b was released to provide standards for ULBs with a battery capable of lasting for 90 days after activation. At the same time, they implemented a restriction against any new 30-day ULBs being developed and approved under the previous version of the TSO. The longer battery life can provide critical additional time for search crews and accident investigators to find CVRs and FDRs after an accident into a body of water. As of December 1, 2015, all newly certified ULBs must have batteries that meet the 90-day performance standard.

Textron Aviation recently began installing 90-day ULBs in new production CVR and FDR installations on all King Air product lines. Fielded aircraft with L-3 Aviation Recorders CVRs and FDRs can easily upgrade to the 90-day ULBs through the L-3 service bulletin applicable to that model recorder. The bulletins provide information for kits which provide the parts required to install the 90-day ULB in place of the current 30-day ULB. This upgrade can be performed without returning the recorder to the vendor or removing it from the aircraft. The installation adds a MOD DOT to the recorder’s identification plate but does not change the part number of the recorder, so no additional aircraft manufacturer approvals are needed. To determine if your aircraft has the 90-DAY ULB, refer to your time life or equipment serialization records. Factory installed 90-day ULBs are listed as L-3 P/N 266-E5542-00. For additional information please contact your nearest authorized service center.

ATA 32 – Nose Landing Gear Strut “Leaking”

There have been reports and questions regarding leaking nose struts on the King Air series aircraft. This oil, that was seen leaking, was not red hydraulic fluid; it was motor oil, brown in color.

All new, overhauled or rebuilt nose struts may have brown oil leaking onto the piston, and possibly the tire for a short time after installation. This does not indicate a leaking strut. This brown oil is coming from the lubrication pad that is saturated in an appropriate lubricating oil per the Component Maintenance Manual (CMM), during overhaul or rebuild. The lubrication pad will only hold a certain amount of oil and will release all excess oil, which can make the strut appear to be leaking. This leakage is to be expected, especially if the pad is over saturated. Some mechanics have lightly squeezed the lubrication pad after saturating it to attempt to remove excess oil. This, however, can remove more oil than intended and it is not recommended.

If a nose strut has this condition, wipe off the excess oil and protect the tire until the leaking stops. If it is determined that red 5606 hydraulic oil is leaking from the strut, investigation is required before further flight.

ATA 33 – Cabin Floor Spar Light Spares Replacement Kit

FL-1 through FL-910; FM-001 through FM-055; FA-001 through FA-231; FF-001 through FF-019

The manufacturer of the spar lights installed in the King Air 300/B300 series announced that they will no longer be supplying the spar lights. Textron Aviation has developed a kit as a spares replacement for these lights. The kit is required because the replacement spar lights require a change in connectors. The kit comes with two LED spar lights and all the instructions to complete the installation. The part number of the kit is 130-3068-0001.

ATA 79 – King Air C90A; C90GT & F90 Drain Oil Hose Spares Replacement Kit

LJ-1063 through LJ-2096; LA-2 through LA-236

The King Air C90A, C90GT and F90 have a requirement to replace oil drain hose part number 109-389009-1 every five years. This hose is very expensive. Textron Aviation has developed a new hose which is less expensive. The new hose can be installed via kit P/N 90-9096-0001. The kit is required because there is a slight variation to the installation and routing of the new hose. The kit provides the parts and information for both engines.

The above information may be abbreviated for space purposes. For the entire communication, go to

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