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Is wearing a personal chute with a bail-out system acceptably safe compared to an airframe chute?

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BJC

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Dear BJC,
Take it from an old skydiver - and jump-pilot - using struts to lever your way out of an airplane only works at low Gs and airspeeds slower than 100 knots. It also helps if you are young, light-weight and athletic.
Even if the pilot only jiggles the ailerons ... you are falling off!
If you try something stupid on the strut, an experienced jump-pilot will beat you with the wing until you fall off! ... maybe conscious?????
Rob, you may have missed my point. Sitting in a spinning / rolling / or both airplane may well be generating acceleration (g's) that tend to hold the pilot in the airplane. I believe that it would be helpful in such circumstances to have something outside of the cockpit to grab and pull on to help crawl out of the airplane. Then the whole idea is to fall off.

I know that I would be hard pressed to exit the Pitts without handholds outside the cockpit.

Yup, I have dismissed skydivers from the strut.


BJC
 

SVSUSteve

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There are certain things only a bailout chute can save you from, such as an inflight fire.
Those of you who know me, know that I am an advocate of being prepared for any contingency but even I have to say: the odds of that are pretty minimal. I can count the number of fatal in-flight fires I am aware in general aviation aircraft of on both hands.

Aside from the weight issue, there are no real downsides to a ballistic parachute and it does not have the drawbacks associated with a bailout.

Not to mention that most things that are going to give you a need to deploy a chute are not going to happen (as others have noted) at an altitude where anyone-- especially someone with little to no experience with skydiving-- is going to have minimal time to bail out (which will be eroded from the hesitation most people feel before a jump even under ideal circumstances) and the odds of serious to catastrophic injury from the chute not having fully deployed before ground contact is pretty substantial. It is better to go with an airframe chute and use that time to allow the chute to decelerate the aircraft. Even if the chute does not full deploy, it will likely improve your chances of surviving the crash.
 

Twodeaddogs

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On that note, has anyone seen a BRS or similar system mounted on a Ridge Runner/Sky Raider/Avid/Kitfox/other clones? I'm struggling with where to attach the tail strap, as well as how the chute leaves the airframe. Short of making a housing with a detachable panel (more weight) and attaching the fabric around this, I'm really not sure how it could work.
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the Kitfox and Avid have that hatch behind the cockpit for accessing the wing fold mechanism so in there might be a good location for a BRS. The Eurofox, a derivative of them, has one there.
 

Vigilant1

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A very neatly installed, spring loaded pilot chute arrangement of a paraglider recovery parachute, perhaps one of these Mayday UL - Apco Aviation Ltd.
Neat, and about the lightest, least expensive whole-plane 'chute I've seen. I'd be concerned about the canopy and lines getting dragged back and tangled in the tailfeathers or tailwheel. Still, if a wing came off, rolling the dice on the parachute would be an easy choice to make.

I wonder if one of the large "G Series' hobby rocket engines would be enough to pull a pilot chute or even a very light canopy to full extension. Lots of things to go tragically wrong with that idea, but it would fill many Sundays with fun experimentation. It's nice to live in a place with a lot of wilderness . . .
 
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Riggerrob

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Weller Rebell is a clever modification of a skydiving pilot-chute. The spring looks like an MA-1 spring from a Vector reserve pilot-chute. Albeit, Weller sewed on a larger diameter "canopy" to better lift the heavier all airplane canopy. The heavier the (all airplane) parachute canopy and the slower the air-speed, the larger pilot-chute needed. Definitely more than a metre (yard) in diameter for an all airplane parachute.
Weller also uses only a single aluminum panel to protect the pilot-chute and (almost) keep rain out; I would not park that airplane outside - exposed to rain - without an additional cockpit and parachute cover.
Like I said, Weller has a clever design, but there is still room for improvement. To reduce risk of entanglement, I would move the pilot-chute to on top of the wing. Then route a bridle (1,000 pound tensile strength or more) down a cabane strut. I would also install a smaller cover flap ... perhaps two smaller cover flaps to reduce the weight that the pilot-chute spring has to push out of the way.
Given all the variables, I would also try to find a stronger spring .. rare among skydiving gear ... Most skydiving springs are in the 18 to 40 pound range ... when compressed all but the last half inch.
Another alternative is installing a second spring. A few parachute containers wrap their pilot-chute spring in a cylindrical cloth bag, but never tie it to the pilot-chute. The bagged spring falls away during deployment, reducing the weight of the pilot-chute. Bagged springs are installed in the Martin-Baker ejection seat in Folland Gnat and "extractor" pilot-chute in the. latest US Army AT-11 reserve.
 

Vigilant1

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Riggerrob,
Thanks for not commenting on the homebrew rocket idea.😉 Or maybe you are digging into a bag a spicy language to properly address it.

A question about the chutes: what is the advantage of square canopies used in those Apco products? maybe cheaper to make (more efficient use of fabric, fewer gores to be sewn)?
 
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Riggerrob

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I took a quick look at the Apco website.
Their 28 gore round parachute looks good. F-111 fabric has been the standard for skydiving reserves since I started jumping in 1977. Most 1980s-vintage skydiving main parachutes were also made of F-111. F-111 fabric starts life with almost zero-porosity, but loosens up after 8oo jumps.
If you are using your all airplane parachute 800 times ... I suggest that you find another hobby!
Most later fabrics start as MIL SPEC F-111, then get less-porous silicone coatings to keep them zero-porosity for thousands of jumps.
APCO's 28 gore round parachute is sewn with the strongest MIL SPEC stitch patterns and reinforcing tapes.

OTOH Apco's "square" parachutes are more correctly called "Rogallos" after Francis Rogallo who invented the concept in 1948. Most 1970s hang-gliders (deltas) are Rogallo pattern with a few tubes to pre-inflate them before take-off. Rogallo is the simplest to sew and the lightest to pack. Circa 1980, Paradactyl was the lightest-weight, smallest-packing skydiving canopy available. I have made one jump on a Paradactyl and rather enjoyed it. Paradactyl was almost as good a canopy as second-generation "squares" (aka. Jalbert, Para-Foil, ram-air).
I also made 4 jumps with its predecessor, the Irvin Delta II. All those jumps were from an open-frame, Breezy. They were all from low altitude ... about 3,000 feet ... and I pulled the ripcord within 3 seconds of exit. All those openings were HARD! Mind you that Delta II only had a primitive, pre-slider, Opening Shock Inhibitor. Once open, the Delta II flew almost as well as the Paradactyl or early Jalberts.

Rogallos' other advantage is that it can be steered ... steered enough to chose between landing your disabled hang-glider in a swamp or a pasture.
Though I am not sure is steering is practical with the long bridles on all airplane parachutes.

Getting back to ultra-light airplanes, I would insist on a canopy sewn to MIL SPECS and equipped with a slider (to reduce opening shock).

As for rockets ... rockets are a great idea ... because rockets can launch the AAP much faster than a simple pilot-chute. Most times, the rocket pulls the parachute to line-stretch before the tumbling airplane can entangle with suspension lines.
Please don't ask me to work on your rocket, because I have limited formal training .. and that was more than 30 years ago ... and I know just enough about rockets to blow my head off.
CAUTION: Always read the manual before playing with rockets.
 
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karmarepair

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Just saw this - rocket deployment test on the ground on a Sherwood Ranger
There are other videos like this on YouTube, and some scary videos of actual deployments on various things for various reasons.
===========================

Riggerrob's comments are super appreciated.

It looks like Bernd Weller keeps his Rebell at his workshop on a trailer; this video shows him preparing it for flight in a legitimate 15 minutes
The changes to the recovery system Riggerrob is proposing would make it a good bit harder to achieve that simple setup.

I'm wondering how you'd go about testing this, short of actually deploying it from a flying airplane, say at 500 AGL above a big open pasture. Maybe try deploying it on the ground with a light twin tied down, running, in front of it? Tie it to the top of a truck running at 60-80 MPH?
 

edwisch

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The ballistic chute alone is only a partial solution. When the plane hits the ground at 16'/sec, a standard rate, something has to decelerate the plane so that the occupant doesn't suffer a spinal compression fracture. Cirrus have a reinforced landing gear for that purpose. But if you come down over water, the landing gear won't help.
 

Riggerrob

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This is a Junkers Softpack 450, I am told. Magnum Softpack Rettungssysteme - Junkers-Profly.de or Magnum Parachutes
It looks like this is more of a CANNON than a ROCKET.
Some AAP/BRS are referred to as "mortars" because they explosively launch the entire parachute from a tube/barrel.

Simpler systems just use a rocket or slug to launch the pilot-chute beyond wing-tip length. Then they depend upon pilot-chute drag to pull the canopy to line stretch. The most powerful slug guns can pull the entire parachute canopy to line-stretch.

Bottom line: the quicker you can pull the canopy to line-stretch, the less likely it will entangle with the tumbling remnants of your airframe.
 

Riggerrob

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The ballistic chute alone is only a partial solution. When the plane hits the ground at 16'/sec, a standard rate, something has to decelerate the plane so that the occupant doesn't suffer a spinal compression fracture. Cirrus have a reinforced landing gear for that purpose. But if you come down over water, the landing gear won't help.
That is why some AAP/BRS deliberately suspend the fuselage nose-low or nose-high. That odd angle converts the nose cone or tail cone into a crumple zone ... to limit passenger injuries.

Another option is installing controlled collapse seat cushions. Ladzlo Pazmany advocated installed solid foam seat bottoms that collapse at a slightly faster rate than human spines collapse. Oregon Aero will cheerfully sew up a set of custom seat-cushions for most certified or kit planes. Kitplanes and Sport Aviation magazines have also published articles about sewing your own seat cushions, ergo , ti is comparatively easy for an upholsterer to include shock-absorbing foam in new seat cushions. The technical challenge is choosing the correct density of foam for the multiple layers.
 

Riggerrob

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Au contraire dear karmarepair,
Adapting my pilot-chute suggestion merely requires sawing a rear corner from one wing panel and bolting the pilot-chute to a rear cabane strut. A wedge-shaped fairing can protect the pilot-chute from wind and rain and will not be noticeable from beyond a wing-tip. Then route the bridle down into the turtle-deck where the parachute canopy is stowed ... as per the original Rebell.
 

cblink.007

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We are required to wear chutes in all Category A tests. In military flight test, Cat A is considered high risk. Also, if we operate out of glide/autorotative distance of land, we wear flotation and emergency breathing systems. If the combined air-water temperature is below 100F, we wear anti-exposure suits. (Of note, this is mandated in the military aviation world)

Bottom line, know how to get out if you had to, on land, in the air and in the water! Wearing any of this gear will mean nothing if you cannot escape.

Also, for what it is worth, unless you are testing at higher altitudes and you already have good ventilation in your cockpit, don't waste your time or money on a fancy fighter pilot-style O2 mask. Yes, we carry them at all times in the Osprey, but only because we do not have passive ventilation unless you are sitting on the ramp. A good smoke hood handy is not a bad thing either.
 
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karmarepair

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Au contraire dear karmarepair,
Adapting my pilot-chute suggestion merely requires sawing a rear corner from one wing panel and bolting the pilot-chute to a rear cabane strut. A wedge-shaped fairing can protect the pilot-chute from wind and rain and will not be noticeable from beyond a wing-tip. Then route the bridle down into the turtle-deck where the parachute canopy is stowed ... as per the original Rebell.
How would you quick attach the pilot chute to the whole airplate chute, when rigging/un-rigging? I'm assuming the pilot chute would stay with the wing, and the canopy with the fuselage....
 

Twodeaddogs

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Just saw this - rocket deployment test on the ground on a Sherwood Ranger
There are other videos like this on YouTube, and some scary videos of actual deployments on various things for various reasons.
===========================

Riggerrob's comments are super appreciated.

It looks like Bernd Weller keeps his Rebell at his workshop on a trailer; this video shows him preparing it for flight in a legitimate 15 minutes
The changes to the recovery system Riggerrob is proposing would make it a good bit harder to achieve that simple setup.

I'm wondering how you'd go about testing this, short of actually deploying it from a flying airplane, say at 500 AGL above a big open pasture. Maybe try deploying it on the ground with a light twin tied down, running, in front of it? Tie it to the top of a truck running at 60-80 MPH?
it reminds me of the rigging pins used in the HM 293, probably the quickest rigging aircraft of all time.
 
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