Hi Valin,

I'm glad you are on the case as well…..  Hope following helps a little?

As you know, there has been a fair bit of dialogue on the canopy issue on the forum. And a while back, I invited forum members to join in a working group to look at the issue and, in particular, look at a safety latch. The outcome was no takers other than colleagues here in Oz. Whilst a few of us already had dual micro switch warning systems installed in our Legacy's, but sadly not the Gerladton or Shepparton Legacys, myself and a few colleagues have been feverishly working on a safety latch design to further reduce risk of the canopy open event.

Cutting straight to where I, and no doubt others may have already got to, but quite likely not all…….

A bit more detail below…..particularly around the risk assessment.  Read on if you're still interested!

As far as a safety latch is concerned, our group here would have between us come up with dozens of different designs, some of which were sufficiently well developed that one could almost start building the CAD drawings / CNC machine inputs files for fabrication of components. The goal was of course to design something that will operate safely and reliably, not hinder egress or external emergency access, and be simple to install both during a build and after build. We short listed a few options, but all required some penetrations in the structure - so I passed these options to Lancair to see if they could provide guidance as to which would be acceptable from a structural point of view – to date no response (I must follow up…). Once we get that guidance, I will most likely build a prototype and install on my Legacy.  I fully intend to publish / share whatever we come up with.

Above said, I had forgotten about Don Barnes' solution where I understand the canopy sits up a little bit unless the canopy latch is in the closed position – that may well largely obviate the need for a safety latch, as I'd presume the noise with even with a slightly open canopy (and even with noise cancelling headsets) would be hard to miss – but may be not 100% fool proof. Anyone know how high the canopy sits up with this mod?  1/2"? 1"?

In order to try and bring a bit of rigour and quantification to the understanding of risk and what measures are useful or not and so forth, I have also done a fair bit of work with event tree analysis to assess how various combinations of check lists, procedures, warning devices and a safety latch effect the risk of a fatal canopy open event. The event tree input assumptions around probabilities of various actions were tuned to match the actual historical risk of a fatal canopy open event.  I found it a powerful way to explore what might happen if one does or does not do or have something…  Very interesting, and not entirely or always intuitive. There is no doubt that a secondary latch gets straight to a really good outcome – provided such mechanism does not present unintended additional risk or compromise structural integrity. I am happy to share in the detail of this "model" if anyone is interested, but the bottom line messages - and noting the inherent uncertainty around many of the inputs and assumptions - of this work were:-