We have heard that one of our competitors loves to tell everyone that our position/strobe lights are susceptible to water intrusion inside the lens, and that this is a problem that our customers will face.

This whole thing started with a problem that we had with the initial batch of Pulsar EXP units that we manufactured.  That initial design had a problem with residual stresses in the molded polycarbonate outer cover that was popping the bond line at the top and bottom edges of the outer cover and allowing moisture to enter the units.   As soon as we detected this issue, we did a comprehensive engineering analysis of the problem, found the source of the residual stress, and changed the design of the outer cover.   All units that had been delivered were recalled, and we replaced them free of charge with the redesigned units.   None of the redesigned Pulsar EXP units have had any issues with moisture or water getting inside, and they have been in the field for over a year now.

Because there were aircraft on the field at Oshkosh in 2009, and a few in 2010 that hadn't responded to the recall, our competitor observed those particular units and assumed that it was a problem with all of our products.  They seem to delight in telling everyone that this is a problem that is inherent to our approach, rather than what is actually was.

We sought out all of the remaining units at Oshkosh this year that had the original lens design and replaced them with the newer design, so we believe we have finally removed all of the units that were recalled from the field.

The good news is that because of this issue occurring early on with the initial Pulsar EXP design, the new Pulsar EXP, the Suntail, the Pulsar NS series, and the new Pulsar lights all benefitted from what we found, and we have been able to implement a design that does not put stress on the bond line so that the cover seal integrity is very robust.

We have passed DO-160E humidity, immersion, and fluid exposure testing for the Suntail and Pulsar NS series lights, and there was absolutely no trace of moisture inside the units after exposure to the test conditions.   Additionally, we have hundreds of lights installed on aircraft that have numerous flight hours on them that have not had any issues with moisture intrusion.  The bonding of the lens to the heatsink is very robust, so the units remain hermetically sealed.  We also purge the units with dry nitrogen prior to sealing them so that there is no humidity inside the units that can condense at cold temperatures.

While we fully expect our competitor to continue to spread misinformation on this topic, we want to make sure that our customers understand the true nature of what had occured.  The engineering process does involve occasional problems, but by carefully analyizing and responding to problems, the final product benefits from what is learned so that those problems that were found don't occur again.

Dean Wilkinson

CTO, AeroLEDS LLC