“I experienced a catastrophic failure of the Chelton Sport/Crossbox 425 coupling, fortunately in VFR weather. This event was I believe a couple years after the combination was introduced to the market as tested and = approved. I fully understand that these complex systems are trial and error (sorry = about the lives at risk) but how can we accept that the system which has been = tweaked by that same staff at Crossbox is this time truly ready for prime time? Crossbow has given us reasons to believe them now. It = would be interesting if Crossbow would also disclose to us where they = went wrong the first time. “

Robert, =

I am sorry to hear that you have experienced trouble with the NAV425EX. Did you contact us for = support at that time? If you still have the serial number or part number of the = unit, I can verify for you if you had the updates that we started in April of = 2006. The failure you describe may be related to these updates and the subsequent = service bulletin. In addition, if you still have the flight log you can = send it to us via email and we can playback the data in order to verify the = performance and get a better understanding of the cause. =

In regards to your request to post = the fixes made to the unit, Crossbow has done this. In fact, we have = posted the process and fixes put that were put in place for this update in great = detail. I personally feel that we have provided more detail than any other = manufacturer that I am aware of including some of the major players in the aviation = industry. You can find the full posting of all of the service bulletins we have = issued using the following link.

http://www.xbow= .com/Support/service_letters.aspx

Crossbow has completed over 40 of these updates since = April of 2006 and we have also continued to sell large numbers of NAV42X = variants to other EFIS manufacturers and general aviation consumers. Crossbow = is an ISO9001 and FAA certified manufacturing facility and has been in = business for over 10 years. We continue to be a market leader in inertial = systems and we are confident in the fix that we have put in place. If you or any = of our customers have any questions or need any technical assistance, please do = not hesitate to contact us. We are 100% committed to our customers and = our products.

Sincerely,

Michael Smith
Application Engineer Inertial Systems
Crossbow Technology
Email: msmith@xbow.com
Phone: 408-965-3388