Magnum, BRS, or GRS?

[MrMorden]

BTW I didn't think Paul was personally attacking me. I did however feel his comments were subtly poking at pilots that chose to use parachutes as part of their training procedures as somehow less well trained and/or more prone to poor decision-making.

[Warmi]

I believe the 95% figure mentioned by JimParker256 originated from this video https://youtu.be/0LwGYBBhTss which refers to water/beach/ditching landings only.

We can argue back and forth how much of an advantage BRS technologies offer but ultimately it is just another tool in the bag and as such it can become positive or negative multiplier depending on who is flying the plane.

If you are a reckless and carless individual, you will use this tool to amplify and justify your recklessness but you are probably already doing it with all other tools at your disposal anyway...

I still see no downside to having yet another safety net included in your flying equation and yes of course you need to know what to do with it but how is that different than any other tool already at your disposal ?

[JimParker256]

Dr Paul, 3Dreaming, and Warmi have all served to educate me further on this topic. And if I were in the market for a new S-LSA today, and the useful load worked out, I would probably check the option box for a whole plane parachute. But I would definitely expect to see some test data about in-flight deployment tests, and I would also expect some factory-approved training on use and deployment of that 'chute.

I'm still not 100% convinced that it would make a huge difference in 99% of the situations I could find myself in, but as Warmi says "it's just another tool in the bag..." So if it has no adverse impact on my flying, why not have it?

When I stop to think about it, much of my concern really stems from concerns about the engineering changes that would need to be made to retrofit a 'chute to an existing airframe that was not originally designed for a 'chute, and the potential to royally screw that up... I cannot imagine that the Randy Schlitter had in mind the kind of vertical stress forces a 'chute would impart when he designed the fuselage cage of my RANS S-6ES... (OK, in this particular case, I do know for a fact that he had no such thoughts when he ran all the stress analysis.) If I fired the 'chute, and it tore the upper structure from the cabin cage, I'm pretty sure I'd be in a worse situation I was prior...

The same was true for the Bearhawk Patrol I was building for a while. Where would it be "safe" to attach the bridle to ensure that it didn't just rip off the top of the cage? The designer wasn't interested in doing that much engineering work to determine where and how to modify the structure. And even if I reinforced it appropriately, would the fuselage attitude be remotely correct on landing to absorb the forces? Would the seat structure work correctly to prevent spinal compression injuries? Etc.

All those things would theoretically have been done by the designer in a factory-supplied 'chute, which is why I'd want to see the test data from actual deployments done before marketing the system.

Anyway, thanks for helping to educate me. You've at least partially changed my view on this topic.

[3Dreaming]

Jim, if you were going to retrofit an existing airplane I expect that BRS would be willing to work with you on the installation. As far as stresses when deploying the chute I don't really think they are excessive. The chute is designed with a slider that slows the airplane down as it fully deploys to reduce stress on the airplane. Do a search on BRS deployments and watch some of the videos.

[JimParker256]

Thanks, 3D. I've watched the videos, and I talked with them up at OSH a few years ago. It was the designer of the airframe I was building at the time who expressed concern about the stresses. I might reach out to BRS and see what they have to say.

[fatsportpilot]

Jim, if you were going to retrofit an existing airplane I expect that BRS would be willing to work with you on the installation. As far as stresses when deploying the chute I don't really think they are excessive. The chute is designed with a slider that slows the airplane down as it fully deploys to reduce stress on the airplane. Do a search on BRS deployments and watch some of the videos.

Is BRS the only company that uses a slider to reduce airframe stress?

[fatsportpilot]

IMO if a pilot is safety-minded then a parachute won't cause them to be more reckless at all. If they are then the fault goes to marketing and training and not the parachute mechanism.

The criticism of some planes not being built for safety in a vertical landing scenario is valid and probably it's very important to be 100% certain that the mfg did stress analysis for not just the fuselage so the rope doesn't rip the airplane apart but also the landing gear and seats so you don't slip a bunch of discs or break your spine.

But the one factor that a parachute is not going to be very effective with is the most common midair and stall/spin scenarios where they happen in the pattern. If you are 650' AGL turning base to final and someone doing a straight in approach NORDO that you didn't see hits you and they snap off your tail then you're going to lose 300' just figuring out what happened and pulling the handle (if the g forces even let you) and another 300' for the parachute to deploy if you're very lucky and probably more if you're in a spin. Now you have only 50' to stabilize and decelerate from free fall to a survivable velocity which just isn't enough.

The other problem it cannot solve is loss of engine on takeoff if there is nothing but trees or houses in front of you.

[fatsportpilot]

The point about seats designed for vertical impact is a good one. I will need to ask the manufacturer. The Bristell (which is one of the planes I am seriously considering buying) has flimsy seats to save weight. The back rest is "free floating" and is held in by gravity and friction from a person leaning back. They advertise it as some kind of feature but it's obvious that it's just a weight saving trick.

The reason I would use it would be only if I could not make a power off landing such as medical conditions, serious loss of control, mid air, or something that would mean my option is between deploying parachute or falling from the sky. If I'm flying up high and the engine quits then I'll probably be fine in most conditions except over the worst terrain but that's never happened to me before and as far as I know I could panic.

Also things like this https://www.aviation.govt.nz/assets/Upl ... ations.pdf

Update on the Bristell situation: https://www.casa.gov.au/aircraft/aircra ... e-bristell