One of the challenges/frustrations with building an airplane is that you sometimes have to make decisions about things that you don’t have all the information on.

With the safety harness, I deviated from plans in that I wanted a 4-point harness with inertia reels for the shoulder harness.  I made this decision because one or the first things I did when I got the Cessna 182-RG was to install these. They are great!  First, because the shoulder harness is on an inertia reel, you can lean forward to reach things that would otherwise be out of reach. Second, having two straps (one over each shoulder) provides much better restraint than the auto style one strap over the shoulder, diagonal harness.

So I started talking with Steve Pekrul and Seatbelt Planet and ended up with a really nice harness system for the front.

But in actual use, it’s not that nice. I mounted the retractor reels on the overhead beam behind the front seat. The webbing has to exit the reel at particular angle and everything lined up. But Because the top of the seatbacks are the proper height (they are actually above my head), the harness has to come over the headrest and then down to the shoulders. So it’s rubbing the back of your head the whole time. And because the point where the two shoulder straps meet is so close, the two straps are always rubbing on the side of your neck. I could have created a slot in the back of the seat and fed the strap through. But the seats are already covered. And it would have messed up the geometry of the strap leaving the reel.

So I decided to investigate the harness that Velocity uses. I found out that their 3-point harness is made by Beam’s which is who made mine. Then I got in touch with my friend Bob who has them in his twin to find out what his thoughts where. His report was mostly positive except that he said the inertia reels don’t always lock in turbulence and while it’s not a problem for the shoulder harness, it is for the lap belt. That isn’t a problem with the 4-point since the lap belts are manually adjusted.

Time for most investigating.

I called up Steve at Seatbelt Planet again. He remembered me because I guess he doesn’t get that many people buying safety harnesses for experimental aircraft. 🙂

I explained what I was looking for is a 3-point harness that will reliably lock in turbulence.

It turns out that Seatbelt Planet was started by one of the people that started Beam’s.  And that they produce some of the components that Beam’s uses in their harnesses.

Steve made some suggestions.  Like using a manual lap belt and a retractor for the shoulder.  But that’s a bit of a kludge.  What we ended up settling on was something called the “Tri-Lock” retractor with a 3-point setup.  The Tri-Lock works like this: In normal mode, it uses an ELR (Emergency Locking Retractor) which locks when you pull too fast or if the mechanism senses an upset.  This is done by means of a small ball in the retractor that if it gets displaced the reel locks.  Because of this the retractor has to be mounted perfectly vertical.  It sounds like this will lock pretty reliably.

But the neat part is when you put it in ratchet mode.  When you pull the harness all the way out, it will retract, but not extend. So if you think there’s turbulence ahead, you can lock it down as tight as you want.

The downside is that if you want it back in ELR mode, you have to unbuckle it completely and let it retract all the way to the rest position. But that would only take one second at the most so I guess that once you’re through the turbulence, you can reset it.

Here’s a video that shows how it works.

Beam’s Tri-Lock

The harnesses came in a couple days ago so I’ll start working on getting the new hardpoints in once I’m done with my very first annual.

The other reason for the new harness is that Ann explained that the harness color that I bought didn’t go with the interior color palette that she is using. 😉