Canopy Pressure gas springs

This subject has been discussed over the years a number of times but I want to make sure an important item is covered. It has briefly been noted on the ASW 27 / ASG 29 group. I have a '29, manufactured in 2012 and from day one the canopy has not been what I felt as safe in the up/open position. I did not take much for it to want to close! With time, it got worse and if I landed with a brisk breeze going down the runway it was hard to get it to stay open while exiting the glider. My instruments are CNV, CN screen, radio, Trigg, mech. vario, ALT, AS, Flarm. Not much more than most gliders and less than some. About 3 years into the ownership I sent the factory an email asking if my issue was normal? Did not get a response. This spring on my first flight it was considerably worse and I had to have it held open when I landed. Contacted Rex the AS dealer for a new gas pressure spring which I received "correct replacement" immediately. I replaced the old one - with lots of help from my 'go to' friend and fellow glider pilot Brian Case - and noted that the original was 1,000N (224.809 lb) and the new one is 1,200N (269.771 lb)or a bit under a 17% increase in strength. Yes, I understand that the gas pressure springs loose about 5% per year in strength but mine was weak to begin with. My guess is that I was not only owner experiencing this issue. That, in recent years, instruments have become heavier and we are all stuffing as much as we can into and on the panel. The factory recognized the problem and in later models put in stronger units BUT did not mention this to existing owners. So, if you are having any concerns about your canopy staying open I strongly suggest you replace the gas pressure spring to the newer stronger unit. From Willian's with shipping it was about $85. Very reasonable compared to a multi thousand dollar canopy if it falls on your head while getting out.
Stay safe.
Boise Pilot

When I had that issue with my LAK-17a, I removed the spring, copied all
the numbers, did a lot of searching and cross referencing on the
internet and found that, for my glider, it was the same spring used in
pairs to support the hood (bonnet) of the mid '90s BMW 735 series.Â* A
quick call to Autozone had one in two days for about $35.Â* I didn't even
have to change end fittings.

On 4/20/2020 12:40 PM, Boise Pilot wrote:
This subject has been discussed over the years a number of times but I want to make sure an important item is covered. It has briefly been noted on the ASW 27 / ASG 29 group. I have a '29, manufactured in 2012 and from day one the canopy has not been what I felt as safe in the up/open position. I did not take much for it to want to close! With time, it got worse and if I landed with a brisk breeze going down the runway it was hard to get it to stay open while exiting the glider. My instruments are CNV, CN screen, radio, Trigg, mech. vario, ALT, AS, Flarm. Not much more than most gliders and less than some. About 3 years into the ownership I sent the factory an email asking if my issue was normal? Did not get a response. This spring on my first flight it was considerably worse and I had to have it held open when I landed. Contacted Rex the AS dealer for a new gas pressure spring which I received "correct replacement" immediately. I replaced the old one - with lots of help from my 'go to' friend and fellow glider pilot Brian Case - and noted that the original was 1,000N (224.809 lb) and the new one is 1,200N (269.771 lb)or a bit under a 17% increase in strength. Yes, I understand that the gas pressure springs loose about 5% per year in strength but mine was weak to begin with. My guess is that I was not only owner experiencing this issue. That, in recent years, instruments have become heavier and we are all stuffing as much as we can into and on the panel. The factory recognized the problem and in later models put in stronger units BUT did not mention this to existing owners. So, if you are having any concerns about your canopy staying open I strongly suggest you replace the gas pressure spring to the newer stronger unit. From Willian's with shipping it was about $85. Very reasonable compared to a multi thousand dollar canopy if it falls on your head while getting out.
Stay safe.
Boise Pilot

--
Dan, 5J

For any application, ambient temp has an impact on function.
Example, wife's car, cool days (older gas struts), opening (rear hatch or hood) would slowly close to a point, then slam shut.
Warm/hot day in sunlight, same system worked fine.
Lubing ballends has an impact. Can help open, may hurt keeping open...

No suggestions on suitable struts for your application.