Heads up: Feedback - Canadian Aviation Service Difficulty Reports

Service Difficulty Reports about heads up that either show a trend or should be known by the airworthiness community.

On this page

• Improvements to the online submission of the Annual Airworthiness Information Report (AAIR)
• Cessna
• De Havilland – CAN
• Beech
• Lockheed
• CANADAIR
• Incorrect Hook and Loop Installation on Emergency Locator Transmitters (ELT)
• Bombardier
• Penney & Giles Aerospace Ltd Multi-Purpose Flight Recorder (MPFR) Internal Corrosion
• Piper
• Aerospatiale
• Boeing
• Engines and APU’s
• V-Band Couplings and Clamps
• Diamond
• Airbus Canada
• Bell Textron – USA
• Pilatus
• Embraer

Improvements to the online submission of the Annual Airworthiness Information Report (AAIR)

On August 2nd, 2018, Transport Canada (TC) launched the newly redesigned Continuing Airworthiness Web Information System (CAWIS) which included enhancements to the online submission of the AAIR. Some of the improvements include:

Login Process

There is now a specific AAIR login page for aircraft owners. The login page will require a User ID and Password instead of an AAIR access code. User IDs will be assigned by TC and will remain the same each year.

For aircraft owners who had an AAIR access code, the User ID is the first part of that access code. For example if your access code was 123456 ABCDE, your Used ID will be 123456.

Owners are now able to create their own unique AAIR password via the AAIR login page and also recover a forgotten AAIR User ID.

Updated Design

The webpage layout has been redesigned in order to facilitate the data entry of the AAIR information. The functionality of certain areas, for example the AMO/AME section, has been updated in order to provide a more user friendly experience.

The most recently reported Hours flown since new and inspection date are now shown to facilitate entering in information previously reported which is remaining unchanged.

Print AAIR anytime

Owners are now able to log into CAWIS anytime during the year in order to print their most recently submitted report.

We hope our continued improvements to the CAWIS system make submitting the AAIR easier to complete. If you have any questions related to the AAIR program, please contact our office at 1-888-663-3639 (Option 1) or by email at tc.aair-raina.tc@tc.gc.ca.

You will find below, email addresses to be used for various situations. To be sure you receive all pertinent information from the National Aircraft Certification branch, we recommend you save these addresses in your contact list and make appropriate adjustments to your SPAM protection.

• TC.DoNotReplyNAC-NepasrepondreCNA.TC@tc.gc.ca: This address is used to distribute safety publications/messages. This mailbox cannot accept incoming emails.
• tc.aair-raina.tc@tc.gc.ca: This address is for all questions/concerns related to the Annual Airworthiness Information Report (AAIR) program.
• AD-CN@tc.gc.ca: This address is for all questions/concerns related to Airworthiness Directives.
• TC.NACcommunications-CommunicationsCNA.TC@tc.gc.ca: This address is for all distribution questions/concerns including updating your email address.
• SDRS@tc.gc.ca: This address is for all questions/concerns related to the Service Difficulty Report (SDR) program including technical support with the online WSDRS system.
• cawwebfeedback@tc.gc.ca: This address is for all other Continuing Airworthiness matters including CASAs and Feedback articles.

Cessna

560 - Engine Cowl Separation - Failure to verify engagement of quarter-turn fasteners

SDR #: N/A

De Havilland – CAN

DHC 6 300 - Service Difficulty Reports Involving Supplemental Type Certificate (STC) and/or Part Design Approval (PDA) and/or Parts Manufacturing Approval (PMA) Parts

SDR #: 20201008019

Subject:

The main landing gear compression blocks on the affected DHC-6-300 were found to be not only compressed, but very deformed. The blocks were noted, during routine inspection, to be sliding off the upper and lower platen surfaces, and no longer of a rectangular shape. The total time in service was 665.4 hours. The block serial numbers are 10249, 10250, 10251, and 10252. All blocks will be replaced at this time.

Beech

200 - Cracked Turnbuckle Body (Barrel) – MS21251 Series

SDR #: 20190604017

Subject:

During a Phase 3 inspection, the inspection of the down elevator cable turnbuckle revealed a crack emanating from one end and progressing very close to the center of the turnbuckle hole. While using a 10x power magnifier, it appears the crack ends near the “6” of the part number stamped into the turnbuckle. The previous operator had proactively set up a 15-year primary flight cable replacement schedule on December 16, 2016. The elevator cables were replaced, the aircraft has since flown 1092 hours/1634 cycles. However, the cable replacement did not include a turnbuckle replacement. The turnbuckle TSN/CSN cannot be confirmed but is assumed to be the life of the aircraft.

1900D - Cabin Window Damage Due to Engine Exhaust

SDR #: 20210903006

Subject:

During take-off roll from XXXX, a cabin window warped by heat detached from the aircraft (emergency exit, front right side). During the initial climb, the pilot-in-command (PIC) realized that the window was missing. The PIC returned to airport XXXX without incident. There were no injuries or fatalities and no secondary damage to the aircraft. Maintenance control determined that the most likely cause of this incident was the right engine idling for too long on the ground with the propeller in flag position.

200 - Aviadesign Inc. Hydraulic Landing Gear Retraction System Fork End Failure

SDR #: 20081027005

Subject:

After take-off when the pilot selected gear up, the right-hand (R/H) main landing gear failed to retract. The gear was cycled again with no success. The gear was returned to the down position and there were three green lights. Dispatch and maintenance were contacted and it was decided to return to base. The landing at base was uneventful. Upon inspection by maintenance personnel, it was found that the R/H main gear actuator fork end that attaches to the upper drag brace was sheared off, however the downlock was still in place.

Upon inspection, it looked like the fork end had developed a fatigue crack and finally let go just above the lock nut that holds the fork end in place on the actuator. The fork end, and tab washer were replaced with new parts. The number of cycles or hours on the broken fork end is unknown. The gear was inspected further and no other defects were found. The gear swings were completed and all checked serviceable. The aircraft is equipped with the Aviadesign Inc. Supplemental Type Certificate (STC) SA4378WP, hydraulic landing gear retraction system, which the fork end is a part of the STC.

Lockheed

L100-382 - Wing Bolts Received New From Supplier Were Found Cracked Before Installation

SDR #: 20180706010 & 20180706012

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

A batch of bolts (part number (P/N) MS21250-12032) was procured in a lot of 50 for use as wing attachment bolts on a Canadian military CC130H Hercules aircraft. Prior to installation, the Royal Canadian Air Force (RCAF) technical order requires that the bolts undergo magnetic particle testing. During the magnetic particle testing, one bolt was found to be cracked longitudinally in the bolt head.

A batch of bolts (P/N MS21250-14038) was procured in a lot of 26 for use as wing attachment bolts on Canadian military CC130H Hercules aircraft. Prior to installation, the RCAF technical order requires that the bolts undergo magnetic particle testing. During the magnetic particle testing, four bolts were found to be cracked longitudinally in the bolt head.

The same bolts are used in civilian registered Lockheed L100-382 Hercules aircraft.

CANADAIR

CL215 6B11 (CL415) - Blocked Vent Openings

SDR #: 20210719024

Subject:

The aircraft was dispatched to a forest fire on 17 July 2021. After start up, the flight crew found the right-hand (R/H) low fuel pressure light on. The aircraft was shut down and the snag was reported to maintenance.

The Aircraft Maintenance Engineer (AME) attempted to troubleshoot the aircraft system, but upon selection of the #2 battery to the ON position, no power was observed on the aircraft. Subsequent troubleshooting of the #2 battery system revealed that the #2 battery case was distorted and the battery lid was bent. The battery was removed from the aircraft for further inspection.

There does not seem to be any evidence of the battery overheating, and the battery was cool when the defect was found. The battery voltage still read 24-25 volts. Removal of the battery lid revealed that the thermal switch was defective with an internal short or other failure. We can also see that one of the cells within the battery was cracked.

We have completed the initial inspection of the aircraft, and have found the pressure portion of the battery vent system plugged (insect). We have been in contact with the aircraft manufacturer (Viking) and have been trying to contact the battery manufacturer to address the cause of the distorted case. All other aircraft in the fleet have been inspected for battery case distortion, and no thermal switches with defects were found. The battery vent systems of the fleet have also been inspected and cleared of any obstructions.

CL600 2B16 (601 3R) - New Tire Found With Metal Protruding From Sidewall

SDR #: 20180716012

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

Following the installation of a new tire on the aircraft main wheel during the tire inflation and pressure test, the maintenance personnel noticed a piece of metal protruding from the tire sidewall. When the tire was installed and prior to inflation, the piece of metal was not visible. The tire was a new part received from a supplier who had received it from the original equipment manufacturer (OEM).

Incorrect Hook and Loop Installation on Emergency Locator Transmitters (ELT)

SDR #: 20181203023

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

It was noticed during an annual inspection that the Velcro strap (included with the S1840502-01 mount) was found with the metal buckle directly overtop the top face of the ELT. As per the Kannad Aviation installation/operation manual, the metal buckle must be positioned on the left or right of the ELT only. The position is listed as a caution that incorrect installation of the Velcro strap could lead to an unsafe condition. Upon removal of the strap, it was found that the factory-installed Velcro strap had its small Velcro tab (which attaches to the backside of the mount to orient the Velcro strap) incorrectly attached to the strap approximately 5.5” from the buckle (normal is approx. 3.5”). This allows for the Velcro strap to be installed incorrectly without the installer knowing it is incorrect (unless they are aware of the proper procedure and figure within Kannad’s manual). The Velcro strap itself does not have a part number, it is only listed as “included with the bracket mount.” It is unknown if this Velcro tab is meant to be glued, sewn, or otherwise attached to the Velcro strap. It is also unknown if it is required for the Velcro strap to be considered in a serviceable condition.

Bombardier

CL600 2B19 (RJ100) - CRJ100/200 – Aft Cargo Door Fitting Cracked

SDR #: 20210304004

Subject:

During a scheduled inspection, a crack was observed on the aft cargo compartment door forward upper door fitting. Fitting to be replaced with a serviceable part.

CL600 2D24 (RJ900) - RJ900 – Fuselage Stringer 20R Corrosion

SDR #: 20200127017

Subject:

During a maintenance check, it was noted that stringer S20R had corrosion damage from fuselage station (FS) FS.927 to FS.954. The corrosion was found when the floor was removed and was located below the underfloor ducting. There was 100% material loss found and the stringer had to be replaced. The final repair was a replacement of the corroded stringer section from factory stringer splices at FS.920 and FS.977.

CL600 2D24 (RJ900) - RJ900 – Aft Cargo Compartment Floor Beam Corrosion

SDR #: 20190531002

Subject:

During a scheduled maintenance check in the aft baggage compartment, the longitudinal cargo floor structural floor beam on the left-hand side at Fuselage Station FS.1000-1031 was found corroded. The area is located near the aft baggage door opening, and after close inspection, the floor beam was discovered to be corroded completely through with a hole at one location. This level 2 corrosion was under the floor track in the noted area and the floor beam section had to be replaced in accordance with approved repair data from the manufacturer.

CL600 2D24 (RJ900) - Level 2 Corrosion – Passenger Door

SDR #: 20190313002

Subject:

During scheduled maintenance, level two corrosion was observed within the passenger door structure below the door handle cut-out. Repairs were carried out in accordance with the structural repair manual and required the replacement of channel part number 601R318057-1 due to the extent of the corrosion damage. The aircraft had accumulated 42 008 hours air time and 21 756 flight cycles at the time the corrosion was found.

CL600 2D24 (RJ900) - Ram Air Heat Exchanger Ducts Cracked

SDR #: 20190412003

Subject:

During unscheduled maintenance actions in the aft equipment compartment, the aircraft maintenance engineer (AME) observed that the left and right ram air heat exchanger diffuser ducts were cracked and separated from their respective heat exchangers. The diffuser mating surfaces had pulled through the attaching hardware, the duct flanges were broken and the ducts were cracked.

BD 500 1A10 - Nose Landing Gear (NLG) Collapsed Oleo Events

SDR #: 20180208005

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

The Nose Landing Gear (NLG) oleo strut collapsed in-service. After touchdown, a very strong shimmy and vibration from the nose gear was observed. The same shimmy and vibration was observed at the (2) previous landings. During the arrival inspection, the NLG was found deflated and fully collapsed. Further inspection found the groove nut touching the sliding tube and the gland nut locking washer displaced and bent.

Recommendations for repair from Liebherr were requested by the operator and the Flight Data Recorder (FDR) data was downloaded for readout and troubleshooting. Bombardier and Liebherr recommended inspections were carried out before returning the aircraft to service.

CL600 2D15 (705), CL600 2C10 (700, 701, 7020 and CL600 2D24 (900)
Frame corrosion under forward passenger door

SDR #: 20170817016

Subject:

While investigating an unrelated defect, corrosion was found in the area under the floor near the passenger door. Maintenance staff removed and replaced the intercostal from frame fuselage station (FS) 310 to 333.00 and from stringer (STR) 25L to 26L as per Structural Repair Manual (SRM) 51-00-00 and Bombardier Aerospace drawing number SH670-31810. Additional corrosion was discovered on the foot of the frame at FS 319.70 between STR 20L to 21L. This frame was also removed and replaced with a new frame as per SRM 51-00-00 and Bombardier Aerospace drawing number SH670-31810. Please see the attached pictures to view the damaged pieces and severity of the corrosion.

CL600-2D24 (RJ900)
Circuit Breaker Panel Burned Through

SDR #20161121006

Subject:

The left hand cockpit main circuit breaker panel was burned through when a foreign metal object contacted the windshield wiper circuit breaker and grounded to the panel door skin. The ensuing electrical arcing burned through the panel creating a hole.

CL-600-2D15 (705)
Equipment Airworthiness Directive on Crew O2 Mask

SDR #20161020005

Subject:

The oxygen mask was received for servicing and the defect noted was "observer mask has a hole in it". Upon inspection and teardown, it was found that the harness assembly was 12 years old and blown. The manufacturer recommends to replace the inflatable harness assembly every 6 years. Upon further inspection, a number of other discrepancies and evidence of improper/substandard maintenance were noted.

The main concern/problem is a blown inflatable harness with over 12 years of service indicates a lack of proper inspection and recommended maintenance. There were no inspection letter markings found on the harness indicating that Zodiac service bulletin (SB) MXH-35-241 was carried out. This SB was required by EASA airworthiness directive (AD) 2011-0090R1 and dates back to June 23, 2011 with accomplishment instructions within 24 months.

The mask assembly was manufactured in November 2001, and the combined diaphragm was dated 2004 which indicates no proper maintenance or overhaul had been done since new. It was also noted that the main casing which was dated October 2009 was replaced during a repair accomplished in 2010, however the combined diaphragm dated 2004 was put back into the regulator.

Service information letter (SIL) 18 recommends replacement of the harness every 6 years, and overhaul every 6 years.

Penney & Giles Aerospace Ltd Multi-Purpose Flight Recorder (MPFR) Internal Corrosion

SDR #: N/A

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

Data recovery on certain Penney & Giles Aerospace Ltd Multi-Purpose Flight Recorders (MPFRs) have been found to be problematic where the aircraft was submerged in water. Corrosion on pins of memory devices, due to an insufficient amount of conformal coating, may occur when subjected to water.

Certain “GEN2” memory modules manufactured between 6 April 2006 and 2 January 2013 may be susceptible.

Piper

PA31 350 - Anti-retraction Solenoid for the Piper PA31-350 Landing Gear Selector

SDR #: 20171108018

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation ( TCCA ) reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

The pilot inadvertently selected gear-up upon landing, resulting in the aircraft, engines and propellers being badly damaged. The landing gear selector mechanism should prevent selecting gear-up with weight on wheels. At the time, it was thought that the gear was selected up just at the moment of touchdown while the wings still had lift and the gear struts were still fully extended. The aircraft was repaired and returned to service.

However, during subsequent maintenance to repair defects noted by the pilot, the Aircraft Maintenance Engineer (AME) checked the landing gear selector mechanism without power-on and he could select “gear-up” without the anti-retraction locking pin stopping the handle. The AME investigated further and removed the anti-retraction portion of the landing gear selector mechanism. The AME found that the solenoid assembly shaft was bent and was stuck in the stop lever hole.

When the shaft was rotated 90 degrees, the solenoid could then move freely through the stop lever hole. Inspections conducted since the gear-up incident had found that the solenoid assembly worked properly, preventing the landing gear selector handle from being selected up. At every 100 hours air time, the PA31-350 event # 2 and # 4 inspections call for inspecting the landing gear selector mechanism and the anti-retraction solenoid.

With the solenoid installed, a bent shaft is not obvious and it would be difficult to detect unless the shaft was stuck in the stop lever hole. If the AME were to rotate the shaft during the inspection, a bent shaft would likely be found. This idea was not considered during previous inspections, nor considered necessary as the solenoid operated normally. Piper may want to add to their inspection requirements, to rotate the solenoid shaft in-situ by finger at the spring flange.

AEROSPATIALE

ATR 42 and ATR 72 Side Window De-ice Burnt Terminals

SDR #: 20190925002, 20171012009, 20190927006

Subject:

The side window anti-ice activated at approximately 4000 feet (ft). By approximately 2500 ft, the pilots could smell electrical smoke, followed by dark grey smoke emitting from the first officer’s side window. At this point, the aircraft was clear of the cloud. The side window anti-ice was de-activated, and Air Traffic Control (ATC) was notified that the aircraft was on final approach with smoke in the cockpit. Upon landing, the side window and the electrical connection for the side window heat began to burn and melt. The aircraft taxied off the runway, with small flames becoming visible. The aircraft was shut down and the handheld fire extinguisher was discharged on the burning portion of the window and the associated electrical connection. The initial investigation points to the fire starting at the positive stud on the electrical connection. There is no evidence of arcing of the positive wiring to the airframe, and it appears to have started internally in the phenolic housing.

Transport Canada Comments:

Multiple events of flight compartment side window arcing have been reported. ATR-GIE and Saint-Gobain Sully (window manufacturer) initiated an extensive technical investigation to determine the cause.

The origin of the arcing was located at the electrical connections between the aircraft power supply and the connector of the side window (fastener with three screws and nuts).

The technical investigation shows that a mechanical clearance between the aircraft crimp ring and the connector screws may cause an increase in the contact resistance and a local overheating/arcing at the level of the crimp rings (terminal lugs) and fasteners.

The technical investigation determined the most appropriate torque to be applied and added an additional nut to the terminals.

Transport Canada Civil Aviation would like to advise ATR 42 and ATR 72 series aircraft operators of the issuance of ATR Airworthiness Operators Message AOM 2021/08 Issue 1. This AOM guides certain aircraft operators to Vendor Service Bulletin (VSB) 56-12-00-SPSATR42 and provides other operators with information on using the new torque values.

 

 

ATR 42 320 - Small bulb, big problem

SDR #: 20150224028

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

A small amount of smoke was noted in-flight, emitting from the reading light in seats 5A/B. The aircraft returned to base and the bulb was replaced rectifying the defect. The company’s safety management system investigation lead to the suspicion that the bulb was an unapproved or counterfeit part. Indications of the part being counterfeit are low quality and overabundance of solder on positive (NON BODY) electrical contact. A complete lack of manufacturing markings or part number (P/N) stamped or etched on the bulb, a lack of solder to secure the bulb housing halves joint, and a smaller than normal insulator separating the bulb housing and center contact.

An inspection of a second company’s aircraft found approximately 1/3 of the bulbs installed in the reading lights were of the unmarked, suspected counterfeit variety and several had significantly melted contacts. Upon this discovery, the reading light system on all 5 company aircraft were deferred and disabled until all the bulbs could be inspected and replaced as required.

ATR 42 - Wheel Assembly Tie Bolt Failures

SDR #:

It has come to the attention of Transport Canada through the Web Service Difficulty Reporting System (WSDRS) that numerous operators of the ATR-42 series aircraft, have had main wheel tie bolts found sheared or missing.

Over the past year, nine SDRs have been submitted via the WSDRS for this problem.

Typically, the operators have reported hearing an odd sound emanating from the wheel assembly while towing the aircraft in the hangar or from the gate. Upon further inspection, most operators find the remains of a tie bolt loose within the cavity between the brake system and the wheel. Other operators have detected the problem upon removal of the wheel assembly, due to tire wear or one operator found the wheel assembly would not hold air pressure.

The manufacturer of the wheel assemblies, Meggitt Aircraft Braking Systems, issued service bulletin (SB) ATR42-32-33, dated June 14 1999, to attempt to address this issue. Meggitt has introduced through this SB an increased torque value and torqueing sequence for the tie bolts, as well as specific cautions as to the use of power and automatic tightening devices.

Most operators send their wheel assemblies out to overhaul facilities for repair and non-destructive testing (NDT) as applicable. It is recommended that the operator ensure the overhaul facility is following the most up-to-date information prior to performing the overhaul and assembly of these wheel assemblies. Special attention should be given to the tie bolts themselves. The Meggitt component maintenance manual (CMM) for the wheel assemblies in the part number 5006856 series has specific instructions pertaining to the inspection of the bolts and nuts, including a Magnetic-Particle Inspection (MPI) for cracks, paying particular attention to the radius under the bolt head and to the threads adjacent to the bolt shank.

The CMM also states “An equivalent bolt maintenance program may be established by aircraft operators with service experience whereby bolts are replaced based on usage.”

Transport Canada recommends following the CMM and SB ATR42-32-33 while operating these wheel assemblies. Doing this should give operators of the ATR-42 series aircraft the life expected from these components.

Boeing

767 328 - Bleed Air Pre-Cooler Air Leak

SDR #: 20180424017

Subject:

Minor edits have been made to the text below taken from the Service Difficulty Report’s Problem Description. Transport Canada Civil Aviation reserves the right to edit for spelling, grammar and punctuation to increase comprehension.

During a regular maintenance visit, metal debris was found protruding from the right hand pre-cooler exhaust outlet of the core cowl. Further inspection revealed separation of the pre-cooler shroud and core cooling fins. Engine bleed inlet and exhaust ducts were inspected for debris, with no debris noted. The engine bleed outlet fins were intact.

The pre-cooler was replaced, along with the right hand engine strut blanket and outboard core cowl. No further damage was sustained due to the separation. There was no evidence noted as to the cause of this defect. No indications were noted by the flight crew prior to the discovery of this defect.

757-2B7 - The Effects of Skydrol

SDR #: 20171004006

Subject:

While approaching the gate, the crew noticed a "left hyd. Qty." warning message appear. The aircraft was brought to a stop at the gate, and shut down normally. Maintenance noticed a large hydraulic leak from the left gear bay, and a total of 5 ramp personnel assisting with marshaling the aircraft were exposed to the atomized skydrol as a result of the high pressure leak. The ramp personnel affected were taken to the hospital with various symptoms, including vomiting. Maintenance staff found the cause of the leak, which turned out to be a ruptured hydraulic line going to the down lock actuator, and subsequently replaced the unserviceable component.

Engines and APU’s
Oil Servicing Safety Issues

SDR #: Not applicable

Subject:

Oil servicing issues continue to occur in the aviation industry, including over and under servicing engines, failing to properly secure oil filler caps and failing to latch access doors/panels. These events can lead to loss of oil and engine shutdown, smoke or odors in the cabin and loss of panels in flight.

Human factors studies tell us that the reason for these events can include complacency, fatigue, distraction, a lack of experience, inadequate training, etc. A properly implemented Safety Management Systems (SMS) can help reduce occurrence rates.

When Transport Canada receives reports of these (and other) types of occurrences, the information is passed on to the type certificate holder (TCH) of the affected product. Transport Canada Continuing Airworthiness works with the TCH towards reducing both the rate of occurrence and the impact.

Some of the resulting corrective actions may include: design changes (such as check valve installation on oil filler necks), awareness campaigns through various publications and revised labeling and placarding.

Maintainers must remember that although oil servicing is a routine task, it is absolutely vital to flight safety. Servicing tasks (however routine they may seem) need to be carried out correctly and completely, in accordance with the latest manufacturer’s instructions. It is worth noting that manufacturers’ websites are excellent resources for safety information regarding the operation and maintenance of their products.

V-Band Couplings and Clamps
Maintenance of V-Band Couplings and Clamps

SDR #: 20170404021

Subject:

Best Practices for Maintaining V-Band Couplings / Clamps

Diamond

DA-20-C1
Teledyne Continental Motors Ignition Switches

SDR #: 20170623010

Subject:

Note: TCCA has made minor editorial changes and additions to the original text of the SDR, for improved reading and better logic flow.

The aircraft was snagged for “engine won`t start”. Troubleshooting was carried out and maintenance found the ignition switch to be faulty. The switch was checked in accordance with Diamond DA20-C1 aircraft maintenance manual (AMM) chapter 74-00-00, p 201- ignition switch test #2, item number 3 on page 202. When tested in the “start” position, the left retard was found to be “open” which was correct, but it was also found that the left and right advance cable points were “open”. These contact points should have read zero ohms or “closed”. A new switch was obtained from the company’s primary base of operation. It was tested in accordance with the AMM, found serviceable and installed.

The defective switch had been replaced for troubleshooting purposes due to an “erratic starter engagement” the previous week. The switch was not checked for correct continuity at that time of installation and had accumulated 21.1 hours in service.

During the current snag troubleshooting, when the switch was found to be defective, there were no new switches in stock at the company’s sub base, so a serviceable switch was removed from an aircraft down for a 1500 hour inspection. When that switch was tested prior to the planned installation to rectify the snag, the then removed serviceable switch was found to have the same defect as the switch with the 21.1 hours in service. The total time in service of the removed serviceable switch is unknown at this time and there is no record of replacement within the previous 6 months. The removed serviceable switch was red tagged and placed in quarantine stores.

Airbus Canada

BD 500 1A11 - Small Foreign Object Damage (FOD) Equates to Big Problem

SDR #: 20200721006

Subject:

A fuel leak was observed at the gate, an emergency evacuation was conducted and the fire brigade was deployed.

The aircraft was preparing for a flight and was parked at the gate after refueling with the auxiliary power unit (APU) running. The flight crew then noted an engine indicating and crew alerting system (EICAS) message suspecting a fuel leak. One of the pilots went on the ramp to inspect the wing and reported a significant fuel leak coming from the right wing fuel vent. The captain ordered an evacuation of the 93 passengers. All passengers were evacuated safely without injuries. The airport fire brigade was requested and deployed to the aircraft. No fire was reported.

A post-incident investigation performed by the operator’s maintenance crew, reported finding FOD in the right transfer float shut-off valve. The flight was cancelled and another aircraft was dispatched to pick up the passengers. A wing tank inspection was completed.

The centre tank was accessed for investigation to check the cleanliness of the centre tank, and to try to locate the fastener with a missing brush seal, paying special attention to the area, where service bulletin (SB) BD500-282003 was previously incorporated. During investigation, the whole centre tank was inspected. No damaged seal caps or other damaged sealant was discovered. Most likely, the sealant was torn off at some point (either during production or during incorporation of SB BD500-282003) and restored, while the fallen bit of sealant was not collected and left in the centre tank.

A220-100 and A220-300 - Airbus Canada Service Letter CS-SL-28-20-0004 – Improved Fuel Check Valve Retaining Wire

SDR #: 20171221007, 20181211019, 20181221003

Subject:

The purpose of this article is to aid in the awareness of Airbus Canada Service Letter CS-SL-28-20-0004 applicable to the A220-100 and A220-300 series of aircraft.

Airbus Canada has received multiple reports of flight crew observing FUEL IMBALANCE master caution messages during flight. Upon landing, maintenance personnel discovered dislodged Fuel Check Valves (Part Number (P/N) 2090199-101) located within the fuel tanks.

There are 6 locations throughout the fuel system (3 in each wing) where the subject fuel check valve is installed. One valve is installed at the Transfer Ejector Pump in the centre tank and 2 are installed at a Tee assembly in the engine feed tubes located in the collector tank in each wing.

The Transfer Ejector Pump check valve prevents backflow of fuel from the wing tank to the centre tank. The check valves located at the Tee assembly provide isolation between each wing when the feed ejectors are in operation and permits engine fuel cross feeding when the electrical boost pumps are in operation.

It has been discovered that the retaining wire which holds the check valve in its correct position is of insufficient diameter, thereby allowing the check valve to become dislodged during normal operation, which allows fuel to bypass the check valve.

An increase to the diameter of the retaining wire has been made by the manufacturer to prevent the check valve from becoming dislodged. The P/N of the improved retaining wire is 2183023-101 and is red in color for ease of identification.

Service Letter CS-SL-28-20-0004 provides instruction for the replacement and installation of the new and improved retaining wire.

Bell Textron – USA

412EP - Float and Life Raft Failure to Inflate

SDR #: 20191127002

Subject:

During the three (3) year functional check of the 412 emergency float and life raft system, the right-hand raft failed to inflate. Following the test, it was discovered that the inflation line to the raft inside the right-hand mid float was not connected.

Pilatus

PC 12 47 – Power Control Lever – Production Issue Advisory

SDR #: 20220215010

Subject:

A new power control cable assembly part number (P/N) 941.94.11.437 was installed. The crew started to comment that the power control lever was jamming when selecting full reverse. Upon investigation, we realized that when full reverse was selected, the power control cable was binding because the flex core of the cable was barely exposed. Thus, there was no longer any support from the cable liner to the inner part (unable to push without sideway play). When selecting full travel (going to reverse), the power control cable rod end would over centre, and going out of reverse became difficult. On the previous power control cable, P/N 941.94.11.419, there was at least one more inch of solid portion of the cable. Pilatus provided a drawing of the power control cable, P/N 941.94.11.437, and the dimension of the rod end portion of the cable was 25 mm shorter on the newly installed power control cable assembly, P/N 941.94.11.437, than on the drawing. Pilatus noticed a production issue with this new power control cable and provided a replacement part under warranty.

PC12 47E - Bleed Air Overtemperature Switch – Revised Test Procedure

SDR #: 20200604010

Subject:

The test procedure listed in Aircraft Maintenance Manual (AMM) 12-B-21-40-06-00A-903A-A was carried out on the bleed air overtemperature switch. According to the test procedure, the switch is supposed to activate at 290℃, ± 6℃. The installed switch failed, as did a new one that was installed. Multiple new switches were checked, and all were activated at 325℃ or higher. Pilatus, the aircraft manufacturer, was contacted and issued Technical Memo TM-12-006654, which revised the test procedure. Under the provisions of the new test procedure, only the original switch passed, the other (all new) switches still failed. It is suspected that there is a bad batch of switches. As there is no requirement to test a new switch prior to installation, it is possible that a faulty switch could be installed.

PC12 45 - Wiring Diagram Manual Error

SDR #: 20201222011

Subject:

The pitch trim switch was changed in the captain's control wheel. The aircraft maintenance engineer (AME) installed tape to mark the wires, but during the removal and installation, some of the tape came off. The AME then consulted the manufacturer's wiring diagram and finished the installation of the switch. The switch was tested for operation, but the correlation between the direction of movement and selection was not completed. The aircraft went out flying and the first two legs were flown by the co-pilot with no issues. The last leg of the day was flown by the captain and a fault was found.

During takeoff, the captain noticed a nose-heavy condition and trimmed the nose down, and the issue continued to worsen. The captain believed he had a stuck elevator and was only able to maintain 1800 feet. The crew returned to the airport and base.

Maintenance troubleshot the issue and thought at first that it was due to a faulty switch. The old switch was reinstalled and the same issue occurred. The wiring diagrams were reviewed again and the switch was wired accordingly to the diagram. We then went to another aircraft in our fleet to verify how it was wired and found it was backward from the diagram. We then wired the new switch the same way as the other aircraft and the function check was completed successfully.

The Pilatus service centre was contacted and we were told that Pilatus had published a service letter about the wiring manual error in May 2009, but have not revised the wiring manual.

Embraer

ERJ 170 200 SU - Troubles with the In-Flight Entertainment System (IFE)

SDR #: 20230310001, 20230410011, 20230410013

Subject:

While troubleshooting the aircraft cabin entertainment system, after it was reported that all video display units from row 18AC to 27AC were inoperative, light smoke and a burning smell were noted originating from electrical plug 11P3402 at seat 24AC when the system was being powered up. The electrical plug was disconnected, and evidence of arcing was observed. Passenger seat 24AC electrical harness A127012-501 was replaced, but the electrical plug 11P3402 had to be deactivated due to a part shortage. The aircraft is currently operating under a minimum equipment list (MEL) extension. The electrical plug will be replaced when it becomes available. Aircraft time: 37100:48 flight hours and 25340 cycles.

While the aircraft was in for heavy maintenance, the IFE power connector at seat 14FD was found to have arcing and burning damage. The harness for the system and connector were replaced at seat 14FD as per the aircraft wiring diagram manual chapter 44-22-51-4 and the supplemental wiring parts manual 20-21-20. No further action was required. Aircraft time: 39418:52 flight hours and 28117 cycles.

While aircraft was in for heavy maintenance, all the left-hand smart video display units (SVDU) up to and including seat 18AC were reported blank. Wiring metered and found no ground present at plug J3 as per wiring manual chapter 44-22-51-04. In addition, found wires WM041-00015-24WH and W041-00015-24BI shorted. Connector 1P3403 at seat 2A was disassembled and found burnt internally. The connector at seat 2A was replaced as per the wiring manual chapter 44-22-51-04 and the supplemental wiring parts manual. Transformer Rectifier Unit was replaced. An operational test of the systems was carried out. Aircraft time: 39418:52 flight hours and 28117 cycles.