Shoulder Harness & Belts

JimC · #1 02-14-23, 11:31 AM

I installed the 4-point BAS system in my SkyMaster and it worked fine. I would change to the rotary buckle instead of the 4-piece attachment. The 4-piece is mechanically simpler, but is harder for passengers to figure out.

I've also installed the AmSafe airbags in another plane and I like them. They come with a shoulder reel but it is NOT required for the airbags to be legal, functional and safe - you can install the lap belt & airbag without the shoulder reel. If you're looking for extra safety for the rear seats this is what I'd recommend. Installation was fairly straightforward (I did it myself with an A&P signoff.) Disconnection is easy if you want to remove the seats for any reason.

CO_Skymaster · #2 02-14-23, 11:40 PM

Thanks for the answer JimC. I wanted to install 3 points, at least in the front seats. I found a person at Amsafe for my mechanic to talk to about the installation.

Karl

CO_Skymaster · #3 02-23-23, 01:13 AM

@JimC

Hi Jim, I have another question for you or anyone else that has a Cessna 337A. I talked to my mechanic about installing the AMSafe 3 point seat belts and he took a look and found there was not a hard point to attach the shoulder harness to without major modifications. He was suspecting he might have to attach to the wing spar. Did your Bas 4-point seat belts require attachment to the wing spar or some other type of major modification? Or did they find another less intrusive way to attach? Was your Bass 4-point seat belt installation STC'ed?

Karl

JimC · #4 02-23-23, 09:04 AM

The BAS installation was STC'ed, and the attachment point was directly behind the pilot's head. We did not drill a hole in the spar, but I don't have more details than that. Remember, the BAS isn't a true 4-point. It has 3 points of attachment on the airframe and 4 points at the main buckle. The dual shoulder straps attach at a single point behind the pilot's head, split to go around the pilot's neck, and then two buckles attach at the center of the pilot's waist.

One nice feature of the AmSafe belts is that the 3rd shoulder harness is not required. Certainly we want it, but it's not a legal necessity. You can install the lap belt & airbag and fly safer than you were before while you wait on engineers and paperwork to determine how you will add the shoulder belt. The shoulder belt needs to cross the pilot's body diagonally, so the attachment point directly behind the pilot's head won't be appropriate.

Kim Geyer · #5 02-23-23, 01:12 PM

I installed the BAS system in 4 of out planes. I did drill the spar like the plans said and yes it was a pain attaching the nut plate working through a little hole on top of the spar

CO_Skymaster · #6 02-23-23, 09:11 PM

Thank you for the answers. I was going for the AMSafe, but there is currently no STC for 3-point on the Skymaster. I guess I like to have that feeling of being securely connected to my seat. I don't have that feeling with a 2-point system. I'm going to investigate the B.A.S seatbelts at least for the pilot and co-pilot. I was hoping that I could do the same to the seats behind me, but if I have to stay 2-point on those, I can live with it.

Karl

hharney · #7 02-24-23, 03:05 PM

I installed the BAS system 12 years ago and I have no regrets. It's a great system and I think the angle that the upper straps are at is comfortable.