I have been having "strange"/erratic issues with my Legacy canopy seal system. After the normal troubleshooting drill, I discovered the canopy, when closed, is apparently pinching off the inlet for the canopy seal (erratically, not always). The seal inlet is in the forward left corner.
The canopy looks like it may be compressing the seal over the inlet hole. Thus, air cannot enter the seal (unless the pressure is quite high to overcome the blockage).
It was making the seal system almost binary at times, (with canopy closed). It needed roughly 20+psi to fight this blockage and inflate the seal. Anything much less and you turned on the pump and nothing seemed to happen (it was actually just pressurizing the line up to the blockage).
I was able to see this as after I installed a tiny UMA gauge to monitor seal pressure. Hard to diagnose without the gauge installed.
Has anyone seem this? I am thinking of "countersinking" the hole in the fuselage where the canopy seal is to relieve pressure in the inlet area.
Also, I would highly recommend checking your Legacy seal pressure. The seal at the 20psi preset mine was at is way too high. Fred M and Charles B ran some rough calculations- the seal can add substantial stress to the canopy latches. 6psi seemed ok (albeit a v short test flight).
Also, I would double check that the latches are always properly adjusted, most recently described by Chris Z. There are more than a couple of Legacys that have had one latch pop open.
Regards
Clark Baker
Legacy 75hrs
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