Peter wrote:
Well, not if the rocket might just explode and kill the pilot
I would assume it had been tested on the ground first.
Cirrus has tested them in the air, and Streifeneder did so, too. All EASA LSA/VLA/Part23 airframes with chute have made at least one ground test under defined conditions and many ULM and Experimentals did not make any tests at all. Some ULM have made ground tests, though. Some of these followed deadly accidents where the chute did not deploy or it was found it just deployed by chance. The BFU has some reports on them.
mh wrote:
..many ULM and Experimentals did not make any tests at all. Some ULM have made ground tests, though. Some of these followed deadly accidents where the chute did not deploy or it was found it just deployed by chance.
Which confirms my point…
I had a 3 people lunch with brs CEO and asked many questions. Cirrus is the exception in terms of testing on ground and in flight (since it was a certified plane not spin recoverable in all cases). The only other certified brs is for cessnas 172 and 182 and were not tested like cirrus. MANY ultralights (even those that weight 400kg empty :-) had no testing at all and still deployed succesfully first time in real life (I know at least 5 different types specific cases). I would say engineering can predict the correct rocket deployment at 95% accuracy (including correct direction), the correct extension of parachute at 90% accuracy (including no entanglements and no tears), and the correct position of ropes around plane (ie plane position while falling) at 85% accuracy, at least in metal types like mine (in plastic planes ropes are better positioned under the skin of the plane). This if the plane flies with positive ias and not in some akward tail slide or inverted spin, etc. Accidental deployment has zero chance in flight (hundreds fly every day). We are talking of a rocket/chute system that, in the case of Galaxy, has already worked in real life on other types and also tested at full deployment speed and full weight with public videos available. Having said all this, we all agree that cirrus-style testing would push the above percentages close to 99pct (which is the actual success rate of the ~100 cirrus deployments so far, when deployed correctly by pilots)
Hence, having 95% possibility of survival is much better than 0% I mean just because seat belts and airbags don’t have 100% survival rate doesn’t mean they don’t save lives.
Agree, that’s why I paid 5k to install the chute in my RV7!
Sure, but if you were to retrofit a seatbelt it would be good to know that it should be attached to the B column of the car, not to the seat, and also good to know if the particular place chosen to attach it has the strength to hold the attachment bolt in an accident. A seat belt that rips out in an accident is useless.
Hence it is a good idea to have at least some enginering input if, for example, the cable underneath the airframe can really hold it, or will break it in half when the chute inflates.
But a good calculation by someone who knows (and I am sure BRS know) would be good enough for me.
LeSving wrote:
Hence, having 95% possibility of survival is much better than 0% I mean just because seat belts and airbags don’t have 100% survival rate doesn’t mean they don’t save lives.
The economics of chutes are far from trivial, they have a big price tag if you can show 100% rate due to their emotional value, 95% is probably not enough for a sure protection against a 0.0001% event but I agree it still better than nothing tough most of people would like them to be sure, otherwise how they are different from adequate training or planing, which comes very cheap compared to a BRS 
I am thinking of someone who got killed in a old T37 ejection seat on something that could probably have a positive outcome without pulling the handle…
Probably, I will need one for a mid air collision and losing wing-stick linkage but other than that I am happy to take the risk
Ibra wrote:
Probably, I will need one for a mid air collision and losing wing-stick linkage but other than that I am happy to take the risk
What about
loss of control in IMC?
severe icing which makes you head for the ground quickly?
loss of engine
at night (without any roads in sight)
over the water (I know you only fly over the water if you can swim in just a swimsuit :))? (I’d rather fall under a parachute than execute a great ditching – minus bragging rights of cours)
over mountainous terrain?
Most of them can be reduced as part of mission choice and planing, tough one can get caught if pushing for 100% dispatch rate or just being more flexible. At the end one will be left with engine off while en-route (small risk but one can can train for) and structural failure (mid-air collision or loss of control: high risk and does not forgive), for the latter a chute comes with a huge benefit for the former, yes it help especially for long cruise over terrain, night, imc, water, ice and fire
I don’t think a chute is that very helpful for engine off/loss of control in the critical phases of the circuit/approach? but honestly, I never looked at Cirrus specs, so you will do me a demo pulling it in the next circuits practice? 
