[woxofswa]

Due to the overwhelming interest the first post garnered on Socata inspired design ideas to incorporate in a RV-10, I will attempt another one for brain trust consideration.

Seat Belts.

I must admit when I first boarded the RV-10 I was not impressed with the gangly shoulder straps hanging from the hooks.

I can certainly understand why someone considering aerobatics or is a closet Red Bull, would want 4 or 5 point harnesses in their aircraft, but my goal for my RV-10 is a comfortable cruiser.

Socata uses a CERTIFIED inertia reel automotive type lap/shoulder strap combo. The reel is at the sidewall floor joint and the shoulder loop is mounted just aft of the door opening. The whole thing disappears from sight when not in use and works just like an automotive belt with full range of motion on the shoulder strap. It is also compatible with the shoulder strap add on airbag system.

To me this idea is a no-brainer.

 

[rv6ejguy]

If you want to cut into the cabin top to install suitable reinforcement for a single point inertial reel harness that does not interfere with rear passenger entry/ exit, you can.

Van's installs real seat belts in all his designs. Twin shoulder straps are far superior to diagonal types in the event of a serious crash where forces may not be straight ahead.

 

[woxofswa]

Ross,
Thanks for the reply. The inertial reel is actually down low where the floor meets the sidewall. It is just the slider loop that is attached at the upper cabin. It all tucks up nicely and is no problem for the TB's for rear seat egress. Your safety argument is valid although a diagonal strap with an integrated air bag would also have its merits. Also, one advantage of the inertial reel is the freedom of movement. A lot of people with fixed straps loosen them so much for comfort and freedom of movement that they become worthless in an incident.

>>Van's installs real seat belts in all his designs<<

According to Van, he also installs Lycomings in all his designs. When I was there they were adamately against automotive based propulsion.

(sorry, couldn't resist no malice. It just goes to show that many people have taken Van's wonderful designs a step or two further)

Discussion and debate is healthy and educational. I have a lot to learn.

 

[w1curtis]

If you want to cut into the cabin top to install suitable reinforcement for a single point inertial reel harness that does not interfere with rear passenger entry/ exit, you can.

Van's installs real seat belts in all his designs. Twin shoulder straps are far superior to diagonal types in the event of a serious crash where forces may not be straight ahead.

Ross,

A number of folks have done this and it does not require any cutting into the cabin top. The inertial reel mechanism are small and can be installed in the same hole if you want to go with the standard two strap belts. You may want to review the Amsafe site before you decide on what is "superior" in a cross country touring machine. I'll also be looking at 3 point inertial reel system, front and rear. Remember this is the RV-10 not an -8, -7 or -4. Don't know what Van's was thinking with that rear seat crotch strap attachment--I left it off.

 

[rv6ejguy]

Ross,

A number of folks have done this and it does not require any cutting into the cabin top. The inertial reel mechanism are small and can be installed in the same hole if you want to go with the standard two strap belts. You may want to review the Amsafe site before you decide on what is "superior" in a cross country touring machine. I'll also be looking at 3 point inertial reel system, front and rear. Remember this is the RV-10 not an -8, -7 or -4. Don't know what Van's was thinking with that rear seat crotch strap attachment--I left it off.

Van's was just trying to make it as safe as possible so you can't fault him there. Convenience was not his design criteria with the twin shoulder straps I don't think. How many race cars have a shoulder belt with inertial reels? None. I'm not understanding how the factory pickup point could have the proper geometry for a diagonal belt system. We carefully look at anchor points and belt angles when setting up restraint systems on race cars.

There is no question that twin straps are safer in a serious accident than a single diagonal. I'll take that one any day. I haven't found the shoulder belt setup any great inconvenience flying my 6A so far. I was adding mainly that you should not just drill a hole any old place in the cabin top to provide the anchor point for the belt. The cabin top is specially reinforced by Vans for this purpose with the factory setup. Notice I did say that you can do it if you wish, you can change the door latches if you wish or engineer a sliding canopy for your -10 like a Navion too . Just carefully consider the mods and their ramifications.

 

[w1curtis]

Van's was just trying to make it as safe as possible so you can't fault him there. Convenience was not his design criteria with the twin shoulder straps I don't think. How many race cars have a shoulder belt with inertial reels? None. I'm not understanding how the factory pickup point could have the proper geometry for a diagonal belt system. We carefully look at anchor points and belt angles when setting up restraint systems on race cars.

There is no question that twin straps are safer in a serious accident than a single diagonal. I'll take that one any day. I haven't found the shoulder belt setup any great inconvenience flying my 6A so far. I was adding mainly that you should not just drill a hole any old place in the cabin top to provide the anchor point for the belt. The cabin top is specially reinforced by Vans for this purpose with the factory setup. Notice I did say that you can do it if you wish, you can change the door latches if you wish or engineer a sliding canopy for your -10 like a Navion too .

I'm not faulting Van's, they just did what was convenient and what they were used to. That does not mean that it is the best solution for the mission at hand--otherwise you would be using a Lycoming, Right?

I would not compare a race car with an RV-10 no more than I would compare it to a family sedan. Just as the mission of a race car is different from that of the family sedan, the mission of an RV-6, 7, 8 is also different than that of an RV-10. If I planned to operate the RV-10 (or the family sedan) as a race car (or RV-6, 7, 8) then I would consider the same type of passenger/crew restraint. But I don't, so I won't.

Personally, I'm looking at the 3 point installation because I wanted the option of installing the Amsafe airbag system. Also, if the comfort and convenience of a 3 point system prevents passengers from "loosening" them up for comfort, then they are inherently safer than the more restrictive dual strap system that they would loosen. Fly with passenger on long trips for a while and you will know what I'm talking about.

Just carefully consider the mods and their ramifications.

In the grand scheme of things, this is a relative minor (and safe if done right) modification compared to some others.

 

[rv6ejguy]

In the grand scheme of things, this is a relative minor (and safe if done right) modification compared to some others.

I agree, this is a minor mod if done right and that is one reason we build- to customize to suit our mission and tastes. Go for it.

Seat belts are there in case something bad happens, aircraft and race car frontal crash forces are pretty similar. Having survived a 38G frontal crash in a race car, a rollover as well as a hard forced landing in my 6A, I'll put my money on the old style stuff- and hope I never have to test it.

 

[N941WR]

The crotch strap is designed to hold the lap belt down, across your hips, in the event of an accident.

The proper way to tighten your belts is to connect everything, tighten the crotch strap to pull the lap belt down, then tighten the lap belts, and finally the shoulder straps.

Should the lap belt ride up, over the hips, it will crush your internal organs, almost guaranteeing a slow and painful death. At least that's what they taught us at driving and safety steward school.

 

[w1curtis]

The crotch strap is designed to hold the lap belt down, across your hips, in the event of an accident.

The proper way to tighten your belts is to connect everything, tighten the crotch strap to pull the lap belt down, then tighten the lap belts, and finally the shoulder straps.

Should the lap belt ride up, over the hips, it will crush your internal organs, almost guaranteeing a slow and painful death. At least that's what they taught us at driving and safety steward school.

I can see this easily happening in the twin shoulder strap type belt. I can't envision this easily happening in a three point type system. You don't see any TC'd four place cross country aircraft with a crotch strap, and only a few with twin shoulder belt type. Again, choose the right equipment for the mission.

 

[rvbuilder2002]

You don't see any TC'd four place cross country aircraft with a crotch strap, and only a few with twin shoulder belt type. Again, choose the right equipment for the mission.

I think this is mostly driven by marketing decisions not what is the most safe.

People (wives) are sold by something familiar...an airplane interior that is the same as their car. If people had to climb in to a Trinadad and belt up like they were getting into a race car it would not invoke the mental thinking that this is as safe as riding in a car.

I will always use all belts that are available, and will install all belts that can be installed. With the gyrations that airplanes can make during a crash I think a four or five point system will beat a three point for safety in a lot of crash situations.

Since a "properly" designed cockpit will allow the front seaters to reach anything they need too... I think it is smart to use a belt system that is the safest for all situations. Just my personal opinion.

 

[woxofswa]

I think it all boils down to the mission and type of flying you are doing. In my opinion, if you are doing the type of flying where a five point harness makes sense and safety overrides comfort, then you should be wearing a helmet as well.
Taxi up in a hot RV-8 wearing a helmet and you could look primo. Taxi up in a RV-10 with everyone including Gramma and little Jimmy in helmets and the other reindeer are going to laugh and call you names.