I am a 3 time offender (two RV6?s and now a 10). I have about 1400 hrs on RV?s and 2000hrs TT. Never had an incident or accident till about a year ago when my passenger door flew open on T/O!!! I remembered Van?s advice to fly the plane and did a circuit. The passenger managed to grab the door as I turned downwind and applied rudder ? the slip helped close the door.
I sent a very detailed report to Van but no comment or reply. The RV10 is a magnificent A/C but the doors are its Achilles? heal!
Over the past year I put my thinking cap on and came up with a very simple but highly effective solution. I have passed it on to Ken and Richard but still no reply. Thought I might share the solution with this forum as I believe ALL RV10?s should have a similar device. It can only improve A/C safety.
I got to thinking that the bonnet of a car has the same potential to cause total havoc if it were to open during travel. A car bonnet has a safety latch which automatically engages when the bonnet closes.
My door latch works in a similar fashion:
First there is a striker plate that is secured onto the lower cabin frame (as seen below). The fiberglass of the cabin door entry has to be reduced both vertically and on the inside, to accommodate the plate, which is "Z" shaped in cross section, so as to provide some undercut on the inside of the door jamb (which engages the latch on the door). The striker plate is pop riveted and epoxied into place - an easy retro-fit.
The top of the plate is at the same level as the edge of the lower cabin frame.
Next the door latch was made up - I cut a hole in the inner door skin and made the latch as seen below. The latch pivots on a U-shaped bracket secured to the base of the door and there is a powerful hinge spring that ensures that the latch engages the undercut of the Z-plate. The name "Staniforth latch" is to honour the poor victim who was sitting in the plane when the door unexpectedly opened!!!!! I recently asked him to come for a fly (and to see his latches) but strangely, he refused!!
The wire spring can just be seen in the photo below.
As the door closes, the spring loaded latch lifts over the striker plate and then drops down and engages the undercut of the striker plate. Very simple, works every time; it cannot not work!!
Both the striker plate and latch are made of stainless steel.
Note the undercut on the latch in the photo below.
It also has a rod that exits through the outside door skin (sticks out about an inch) so that it can be deactivated when opening the door from outside.
The latch has three functions, one expected and two not:
(i) once the door closes, there is an obvious "clunk" as the spring loaded latch engages the striker plate and drops into place, and even if the pilot/passenger fail to close the main door latch (pins), the door cannot open - this function I expected.
Additional (unexpected) functions are:
(ii) once the latch/striker have engaged, it pulls the door inward SO THAT THE DOOR PINS HAVE NO OPTION BUT TO ENGAGE - this overcomes the problem of the opening effect of the gas strut and the door seal pushing the rear of the door outward, and the rear pin failing to engage.
(iii) in-flight, the latch carries load. This means that the doors actually flex outward because of aerodynamic forces, which are carried by the latch! I have tried to open the safety latch in-flight and they become really tight because of the load they are carrying. This reduces the forces that have to be carried by the door pins.
At a recent SAAA (Australia) fly-in I had several RV10 builders have a look at my plane and especially the doors, and comments were very favorable. All of the other three RV10's at the meeting, had damage to the fibreglass associated with the rear door pins!!
BTW, I have fitted an air-conditioning unit and this really increases comfort in this very, very hot country - a MUST, I would say! I fitted a FlightLine system and it works as advitised!