To reduce the effects of corrosion on aircraft parts and components, maintenance and repair departments perform routine inspections. The standard procedure for one of Navy aviation customers was to inspect lower antennas on aircraft every 28 days and all other antennas every 56 days for signs of corrosion. The inspection process was time-consuming. It involved removing the antenna, conducting the inspection, treating corrosion, reinstalling the antenna and finally, resealing the perimeter. The resealing process generally took more than a day because the sealant required 24 hours to cure.
Upon discovering and applying Av-DEC gaskets, the customer found that there were no signs of corrosion during their regularly scheduled inspections. This led to a re-evaluation of their inspection schedule and a new 90-day interval being adopted. During the rescheduled inspection the antenna interfaces remained free of corrosion and further re-evaluations using data collected thereafter eventually allowed for an inspection schedule to be set for every 546 days.
With Av-DEC gaskets our customer exponentially improved inspection timelines. This caught the attention of the Original Equipment Manufacturer (OEM). Today, the OEM makes use of Av-DEC gaskets in the building and assembling of its military products.
The Benefits in Detail:
The sea provides a harsh environment for ships, barges, oil rigs, and other equipment. This environment produces corrosive agents that negatively affect the structure and components of ships. To prevent corrosion of ship antennas, Naval Sea Systems Command (NAVSEA) sought the aid of Av-DEC gaskets and performed an experiment to determine the effectiveness of the gaskets. The experiment involved installing Av-DEC gaskets on antennas on one side of a ship while the current approved method was installed on the other side. Three ships were outfitted in this configuration for a fifteen-month test.
At the end of the test, a comprehensive inspection discovered that Av-DEC gaskets completely protected the antennas from corrosion for the full fifteen-months. On the other side, the antennas had succumbed to corrosion and needed either refurbishment or replacement. As a result, NAVSEA approved Av-DEC gaskets to prevent corrosion on ships.
The Benefits in Detail:
The installation of aircraft electrically bonded connectors has always been a painstaking and time-consuming exercise. Our customer was installing 40 connectors on a pressure bulkhead, making the process even more taxing. Av-DEC was approached by an Original Equipment Manufacturer (OEM) to develop a faster installation solution for connectors on the pressure bulkhead. The installation process included sealing the perimeter to ensure the connectors were airtight and electrically bonded. Previously, the OEM had used conductive polysulfide to accomplish this task, which was extremely time consuming.
On assessing the difficulties the OEM faced, Av-DEC designed and built a customized gasket for this particular project. The gasket was designed for easy installation while simultaneously eliminating cure times. On application, the custom connector gasket ensured the OEM's needs were met in record time. The quick installation time cut 48 hours of labor down to 6 hours for the entire installation.
The Benefits in Detail:
As with most sales cycles, this started with a call. The call was from a customer looking for a sprayable sealant which could be applied on 3D-printed aircraft components. After an internal consultation to determine which sealant would work best, TufStuff® (TS1228) was recommended to the customer for testing. Weeks later, the customer confirmed that the TS1228 had been successfully applied to the 3D-printed component and met the performance specifications they required from the seal. This meant the seal would continuously be used alongside the 3D printed component as needed.
The Benefits in Detail:
In June 2017, a customer contacted Av-DEC concerning troubling water intrusions experienced by their V-22 Constant Frequency Generator (CFG). An on-site visit was scheduled to assess the problem before a solution could be provided. During the visit, Av-DEC discovered the problem was due to gaps between the Generator Control Unit (GCU) and the CFG, as well as the use of an inadequate gasket. To solve the water intrusion problem and completely seal off the area, an innovative solution was needed.
To devise an applicable solution, Av-DEC took drawings of the different gasket footprints and proceeded to create production blueprints that could serve the customer's needs. The end product was an innovative enhancement of Av-DEC standard 0.045" thickness HI-TAK Polyurethane Rolled Sealant (PRS®) HT3935-7FR fire retardant gasket material. The enhancements were expected to compensate for the gap between the GCU and the CFG and form a complete seal. To apply this innovative solution, the GCU and the CFG had to be separated before the gasket - consisting of two oil tube ports and a wiring port - could be installed. An initial bead of Av-DEC Thixoflex® Gray thixotropic fire-retardant polyurethane sealant was then applied on the perimeter of the gasket. This was immediately followed by a second bead to the top of the initial bead. The result after 400 hours of flight was a completely dry CFG unit that experienced no failures. The successful elimination of the water intrusion problem led to the generator's vendor incorporating Av-DEC gaskets and sealants into their maintenance and installation manuals.
The Benefits in Detail:
The protection of transmission accessory mounts against corrosion is an important priority for aircraft maintenance crews. This was why a customer installed Av-DEC transmission accessory mount gaskets on a military aircraft. An Av-DEC engineer was on-site to assist with the installation process, which went well. The military aircraft was subsequently deployed twice, used for rescue missions, and was in the hangar when a fire suppression system went off.
After 18 months in operation, the same engineer was sent to handle the removal of the Av-DEC gasket. On removal, a photo of the forward bridge mount was taken and shown to the customer, who notably remarked 'you could eat off that thing'.
The Benefits in Detail:
A commercial airline was replacing between 30 and 90 seat tacks with every scheduled inspection they conducted. These extensive replacements where required because of corrosion-related problems and constant use. To mitigate this problem and drastically reduce the number of seat tracks needing replacement, the commercial airline turned to Av-DEC Self-Leveling® Green FR. After installation, the scheduled checks were conducted, discovering only two seat tracks that required replacement.
The Benefits in Detail:
In 1999, a commercial airline began using Av-DEC HI-TAK PRS to prevent corrosion in cargo bay and cabin areas that were susceptible to water traffic. The initial installation was a trial period with a duration of two years. The HI-TAK PRS ability to create a watertight seal was so impressive that installation on additional aircraft was undertaken. This time the inspection was done after six years with minimal to no signs of corrosion discovered.
These successful trials led to the customer installing HI-TAK PRS on every aircraft they took delivery of prior to putting them into service. The customer also recommended Av-DEC HI-TAK PRS to other commercial airlines and today, approximately 5,410 individual aircraft around the world are flying with our products onboard!
The Benefits in Detail:
In extreme cases, excessive corrosion has been responsible for faulty altimeter readings which has led to aircraft accidents. A prominent example of this problem was an aircraft crash in 2009. In this case, complaints about faulty altimeter readings due to corrosion had been made prior to the accident.
To forestall further corrosion and its effects on altimeter readings, the aircraft Maintenance Repair Operations (MRO) started installing Av-DEC Radio Altimeter (RAD ALT) antenna gaskets on the aircraft. Since the installation of the RAD ALT antenna gaskets in 2012, the customer has not reported any antenna corrosion problems that could cause faulty altimeter readings.
The Benefits in Detail:
In many cases, the end result of excessive corrosion is defective antennas that need to be cut out. This was the case for a customer whose aircraft were experiencing excessive corrosion due to water ingress into the Traffic Collision Avoidance System (TCAS) connectors. This irreparably damaged the TCAS antenna and connectors in the customer's fleet. Things got so bad that the customer actually was forced to cut out and remove TCAS antennas from some of their aircraft.
To forestall corrosion in other airframes, the customer turned to Av-DEC. Av-DEC devised a corrosion prevention solution consisting of antenna gaskets, Self-Leveling® Green, and connector wraps. On application, a complete seal was formed and the TCAS antenna and connectors were protected.
The Benefits in Detail:
Av-DEC Sealants have been used to successfully eliminate water ingress in aircraft assemblies. A prominent example of its use is in the installation of aircraft windows. A while back, a jet leasing business approached Av-DEC with a water ingress challenge. The issue involved water ingress around the window, which led to delamination of the window and ultimately caused heating coils to fail. The defective heating coils then caused the windows to crack and the aircraft was finally grounded for security reasons.
To get the aircraft off the ground, a new window had to be installed. This is where Av-DEC HI-TAK® TufSeal® (HT3000), HI-TAK Polyurethane Rolled Sealant (PRS®) (HT3935) and Thixoflex® Gray (TG8498) sealants were used. With the use of these sealants, the customer cut down the average installation duration from approximately 72 hours to 12 hours. Upon completion, the water ingress issue was solved, cracking was eliminated, and the lifespan of the window was prolonged.
The Benefits in Detail:
In aviation, WOW (weight on wheels) switches are used to indicate the physical status of airframe components. A rash of erratically functioning proximity switches had forced one airline to constantly replace them. The cause of the problem was discovered to be corrosion due to moisture ingress.
Moisture was ingressing into the switch, causing a false sensor reading to be generated in the cockpit. In certain situations, the warning light would cause a ground-hold even though the pilots knew that landing gear was in the down position. Safety procedures stipulate that pilots cannot take off if their landing gear indicators can't accurately report the gear's position.
Nineteen sensors per aircraft were affected on the both the forward and aft landing gear plus seven located at the spoiler door. Corrosion led to elevated rates of switch removal which was costing the airline approximately a million dollars every three years. To solve the moisture ingress and corrosion challenge, the proximity switches' back-shell was sealed using Av-DEC Self-Leveling Green while Av-DEC StretchSeal® and Self-Vulcanizing Rubber tape were used to wrap the wire bundle. Regular inspections had previously been set at 1000 hours, but after inspecting the switches and application perimeter, no traces of corrosion were found. This led to the commercial airline increasing its inspection timelines to 5,000 hours, drastically reducing turn-backs and cancellations.
The Benefits in Detail:
A fractional business jet operator with a large fleet of aircraft was having issues with aircraft dispatched delays due to sealant cure times. These delays could potentially affect their flight operations requiring them to re-route aircraft or provide supplemental lift. The operator implemented Av-DEC's fast curing Thixoflex Black (TG3212) sealant on areas such as antenna fillet seals, panels, lights, leading edges, and windows. Av-DEC TG3212 sealant was fully cured in 2 hours. Alongside this, the maintenance department can beneficially utilize TG3212 during overnight maintenance to dispatch the aircraft the following morning.
Thixoflex Black has become the go-to sealant when a quick cure time is needed and has helped significantly to reduce aircraft dispatch delays due sealant cure times. Additionally, the TG3212 sealant is non-hazardous and does not require any special hazardous material paperwork to ship it. This comes in handy during an Aircraft on Ground (AOG).
The Benefits Detail:
A business jet operator contacted Av-DEC for an effective gasket to protect its wing access fuel panels from corrosion and fretting. They were typically having to repair or replace anywhere from 12-14 fuel panels at every heavy check. Av-DEC suggested implementing HI-TAK® Fuel Access Panel Gaskets to help prevent corrosion. The pre-cured gasket was quickly applied, providing a complete environmental seal for the fuel access panels to help prevent the corrosion and fretting. The conductive mesh provides a low electrical resistance bond for lightning strike protection.
The Benefits in Detail:
The success of Av-DEC sealants or products when used by Original Equipment Manufacturers (OEM) and larger aviation service bureaus has been covered in great detail. Small- to medium-sized businesses have also taken advantage of the corrosion-prevention features of Av-DEC products. A perfect example was the application of HI-TAK Polyurethane Rolled Sealant (PRS®) (HT3935), Thixoflex® Gray (TG8498), and Thixoflex® Black (TG3212) products to fix corrosion on an aircraft's windscreen. In this case, the customer was a small charter company and the application was made with great success.
The engineers at the hangar next door noticed the success achieved with Av-DEC products and proceeded to use it as a sealant on their own aircraft. Once again, the TG3212 delivered and was referred to another engineering outfit that repaired rotorcraft. Av-DEC TG3212 was applied as a sealant in the rotorcraft to even greater success and since then, the series of hangars have continued to use Av-DEC corrosion prevention products.
The Benefits in Detail:
A commercial airline had a high flight deck window removal rate because of the environment its aircraft operated under. The airline installed new flight deck windows and used sealants to help prevent corrosion and keep the installation in place. The sealant they used had to be covered with speed tape until the sealant gelled. The process was time-consuming and ineffective in the long run as the high removal rate remained.
The customer chose to try Thixoflex Black (TG3212) and conducted tests to determine its effectiveness as a sealant. After the tests, the commercial airliner submitted a request to the aircraft manufacturer to use the Av-DEC sealant. The request was granted and after a year its success was so encouraging that the TG3212 was applied across the airline's fleet whenever installing flight deck windows.
The Benefits in Detail:
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