BRS chutes. Why doesn't everyone use them?

Another way to look at it...

Of all the ways we can spend dollars and pounds (of weigh) to improve
safety, is a BRS chute the most effective? Will it save the most
lives per pound (or per dollar?)

Martin wrote:
Another way to look at it...

Of all the ways we can spend dollars and pounds (of weigh) to improve
safety, is a BRS chute the most effective? Will it save the most
lives per pound (or per dollar?)

A reasonable question to pose for any safety device; consider:

A PowerFLARM costs ~US$1800 per plane and can prevent only midair collision
accidents - but presumably only if a large proportion of other aircraft
invest the same amount. How much does one's safety improve for that
investment?

A BRS costs ~US$3100 to ~US$4500 per plane and can can prevent injury or
death after midair collision accidents and in other situations. No other
aircraft need to invest in it to make it work for your aircraft. What
fraction of fatal accidents would a BRS have turned into non-fatal
accidents? How much does one's safety improve for that investment?

On Jan 23, 10:18*am, Jim Logajan wrote:

A BRS costs ~US$3100 to ~US$4500 per plane...

Is that just for the BRS system, or does that include installation?

Thanks, Bob K.

Bob Kuykendall wrote:
On Jan 23, 10:18*am, Jim Logajan wrote:

A BRS costs ~US$3100 to ~US$4500 per plane...

Is that just for the BRS system, or does that include installation?

Thanks, Bob K.

That is just for the BRS, as I presume you already know. I think you would
have a better idea of installation costs than I would. I'm sure it depends
somewhat on whether it is designed in from the start, or after the fact.

Since LSAs have been designed with it in mind and their cost has not been
that much above those without BRS, I would guesstimate installation cost to
be as much as an additional $1000 to $2000.

At 18:18 23 January 2011, Jim Logajan wrote:

A reasonable question to pose for any safety device; consider:

A BRS costs ~US$3100 to ~US$4500 per plane and can can prevent injury or

death after midair collision accidents and in other situations. No other

aircraft need to invest in it to make it work for your aircraft.

A BRS will make *some* otherwise fatal midairs survivable. Some midairs
are survived by continuing to fly the glider to a landing. Some midairs
are not survivable under any circumstances, if the pilot is killed in the
collision.

What
fraction of fatal accidents would a BRS have turned into non-fatal
accidents? How much does one's safety improve for that investment?

Given that most gliders are flown by pilots wearing parachutes, seems to
me what we have to consider is what fraction of accidents are made
survivable by a BRS that would not be survivable with an individual
parachute. Inability to get out of the aircraft is the only circumstance
that comes to my mind.

BRS probably sells best to power planes where the occupants typically do
*not* wear parachutes.

Jim Beckman

Jim Beckman wrote:
Given that most gliders are flown by pilots wearing parachutes, seems to
me what we have to consider is what fraction of accidents are made
survivable by a BRS that would not be survivable with an individual
parachute. Inability to get out of the aircraft is the only circumstance
that comes to my mind.

I know of several accidents where pilots didnt't get out of the glider,
and I even knew some of those personally. A BRS may or may not have
saved their lives.

The main problem is that is is very difficult if not impossible to
retrofit a BRS to most existing gliders. And new glider types are mostly
built around existing fuselages, whle a BRS would require a complete
redesign of the fuselage.

On Sun, 23 Jan 2011 12:18:03 -0600, Jim Logajan
wrote:


A PowerFLARM costs ~US$1800 per plane and can prevent only midair collision
accidents - but presumably only if a large proportion of other aircraft
invest the same amount. How much does one's safety improve for that
investment?

A BRS costs ~US$3100 to ~US$4500 per plane and can can prevent injury or
death after midair collision accidents and in other situations. No other
aircraft need to invest in it to make it work for your aircraft. What
fraction of fatal accidents would a BRS have turned into non-fatal
accidents? How much does one's safety improve for that investment?

Close to NIL.

- A BRS can NOT be retrofitted to any existing gliders apart from the
few that were designed for it (which are, at the moment, only special
versions of Ventus 2 and Discus 2).

- Why let the accident (=collison) happen in the first place? FLARM
lowers the probability of a collision a lot, a BRS doesn't.

- A BRS is NOT going to save you from a low-level stall, nor a CFIT.

- NO BRS has ever been tested in an extreme situation (one wing or
tailplane gon, violent spin, high positive or negative g-loads).

- Read the limitations on current BRS systems (especially, read the
limitations for the Cirrus). Prepare to be amazed.


What is the scenario where a BRS is a reliable help?
At the moment, straight and level flight below Vne. Usually such a
condition means a controllable glider.
Ask yourself if you would deploy a BRS in such a situation.



A better solution than a BRS?
Soteira by Akaflieg Darmstadt - a rocket that pulles the pilot and his
parachute out of the glider. No speed limits, no g-load limits, low
probability to get tangled in a spinning glider. Zero-zero capability.



Cheers
Andreas

- NO BRS has ever been tested in an extreme situation (one wing or
tailplane gon, violent spin, high positive or negative g-loads).


Huh? http://www.youtube.com/watch?v=JrVxp_gyTcI

Tony

On Sun, 23 Jan 2011 20:31:50 -0500, Tony V
wrote:


- NO BRS has ever been tested in an extreme situation (one wing or
tailplane gon, violent spin, high positive or negative g-loads).


Huh? http://www.youtube.com/watch?v=JrVxp_gyTcI


Hey Tony,

we are talking about gliders, not ultralights!

There have been quite a few successful BRS recoveries indeed - but an
ultralight is a lot slower than any glider (BRS systems are usually
restricted to 150 kts which a tail- or wingless glider will quickly
exceed), smaller, and lighter, and unfortunately at least in Germany
there have been lots of attempted BRS activations in ultralight
aircraft (two seats, maximum takeoff weight about 900 lbs, cruise
speed between 100 and 140 kts) where the BRS didn't work - because it
hadn't been tested in that part of the flight envelope.

Sorry, but in aviation I don't trust such complex systems if they
haven't been thoroughly tested.

If you take a closer look the BRS in this case didn't work correctly
either - the lines got tangled in the tail, therefore the aircraft
impacted vertically. Fortunately the parachute of the BRS was
oversized, it opened and the structure was rigid enough to prevent the
engine to be crushed into the leg area of the cockpit - but it was a
close case.


Statistics clearly show that the problem is to leave the aircraft (be
it a glider or an F-16).

Why try to save the whole aircraft with a huge and complex parachute
(whose size causes a pretty narrow escape envelope) with the need to
handle impact forces and masses behind the pilot (which try to crush
him on impact) if the only problem is to get him out of the cockpit?

Get the pilot out of the cockpit somehow and let him use his proven
parachute that has proven lots of times to work reliably in the speed
range of a (broken) glider.
Soteira.


Cheers
Andreas

On Mon, 24 Jan 2011 01:36:45 +0100, Andreas Maurer
wrote:

A better solution than a BRS?
Soteira by Akaflieg Darmstadt - a rocket that pulles the pilot and his
parachute out of the glider. No speed limits, no g-load limits, low
probability to get tangled in a spinning glider. Zero-zero capability.


Andreas is a reliable source of rational opinions and solutions.
Here I just want to add a link to the Soteira system. Some partial
experiments have been successfully tested. If development goes on, it
might work safely from zero altitude and speed.
Please remember that up until now, a crash in a glider means that
most of the damage to the pilot is created by the mass of the glider
_behind the pilot_.

http://www.akaflieg.tu-darmstadt.de/...onsprinzip.php

aldo cernezzi