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  #21  
Old 04-21-2008, 11:45 PM
JimLogajan JimLogajan is offline
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Quote:
Originally Posted by szicree View Post
I'm sure it's better than nothing, but coming down onto the rockies at night under that BRS seems like a pretty grim proposition to me.
Actually that scenario has already happened. Here is an article with some photos of a Cirrus that descended under a BRS over the Rockies in British Columbia - at night too(!):

http://www.flyingmag.com/article.asp...7&print_page=y

Close call!

This article makes an attempt to determine to what extent, if any, a BRS might improve your odds of surviving an otherwise fatal crash (about 20% improvement, by his reckoning and attempting to estimate failures to deploy):

http://www.flyingmag.com/article.asp...&page_number=1

(Hopefully those two links work!)
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  #22  
Old 04-22-2008, 10:02 AM
the_other_dougreeves the_other_dougreeves is offline
 
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Quote:
Originally Posted by szicree View Post
I'm sure it's better than nothing, but coming down onto the rockies at night under that BRS seems like a pretty grim proposition to me.
Coming down onto the rockies at night without a BRS or engine seems even more grim to me. The Cirrus that went down landed on about a 20-30 deg slope. I'd rather hit it coming straight down at 500 fpm and 0 forward velocity than 60 kt forward velocity and 500+fpm.


It's been said many, many times: a BRS will not necessarily save you from a bad decision. It just gives you one more option if you have a problem.

TODR
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  #23  
Old 04-22-2008, 10:35 AM
szicree szicree is offline
 
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This is exactly my point. It was suggested that single-engine mountain flying at night is too dangerous, but that the risk becomes tolerable with a BRS. In other words, a pilot is emboldened by the BRS to take risks he wouldn't/shouldn't take otherwise. I think this is exactly the argument that many have against such a device.

I have no strong opinion either way, but I'd love to see a complete rundown of every single time one has been deployed. I suspect that there have been at least a few cases where deployment was the wrong decision and led to a "non-save".
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  #24  
Old 04-22-2008, 12:16 PM
the_other_dougreeves the_other_dougreeves is offline
 
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Quote:
Originally Posted by szicree View Post
This is exactly my point. It was suggested that single-engine mountain flying at night is too dangerous, but that the risk becomes tolerable with a BRS. In other words, a pilot is emboldened by the BRS to take risks he wouldn't/shouldn't take otherwise. I think this is exactly the argument that many have against such a device.
I understand what you're saying, but let me clarify what I was trying to say: BRS is one way of improving the outcome of a flight when we have upstream failures, i.e., it can give us an alternate outcome if we have a failure. However, it is not a guaranteed good outcome, just an alternate outcome.

Do pilots act differently if they have a BRS onboard? I don't know; perhaps. But not installing one for that reason makes little sense to me. We might as well then leave out all gyros unless the pilot and airplane are rated for IFR since they might be tempted to press on VFR in deteriorating conditions because they have gyros. How could that possibly improve safety? Perhaps the argument about new technology allowing more risk was used when seat belts were installed in cars too.

The PIC should evaluate the risk associated with each flight. In CAP, we used to complete a worksheet that numerically assessed risk based on individual factors, e.g., PIC total time, time in type, currency, crew ratings, aircraft equipment, weather, etc. If the total score was above a certain amount or there were any "No-Go" items, you scrubbed the flight.

A BRS is not a substitute for weighing the risks of any individual flight. It does not improve the odds of a successful flight, i.e., one where the airplane and occupants are delivered safely without damage. It's more like a dual battery or alternator setup - if things go wrong, it can stop the chain of failures or provide a more predictable failure mode to improve the outcome.

I fully reject the idea that a builder shouldn't install a BRS solely because it might lead him to undertake some risky flights. Our could say the same about building an aerobatic airplane, flying single engine IFR, flying out of a non-towered field, etc. Heck, one could make the case that one should never fly at all. Let's focus on the pilot and their decision making.

Instead, the decision about installing a BRS should be about the failure frequency of the airplane and its systems, where you will be flying and other risk factors, as well as design considerations (e.g., weight, max deployment speed compared to the flight envelope, etc).

TODR
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  #25  
Old 04-22-2008, 02:14 PM
rfinch rfinch is offline
 
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Quote:
Originally Posted by Andy_RR View Post
If ESP, ABS, airbags etc were the panacea to road safety, we would see startling reductions in RTA fatalities by now.
It's not that simple. See Wikipedia's entry on the NHTSA and how far behind the US often is compared to the now international ECE standards.
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  #26  
Old 04-22-2008, 03:00 PM
Steve Brown Steve Brown is offline
 
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Default Not too dangerous

Quote:
Originally Posted by szicree View Post
This is exactly my point. It was suggested that single-engine mountain flying at night is too dangerous, but that the risk becomes tolerable with a BRS. In other words, a pilot is emboldened by the BRS to take risks he wouldn't/shouldn't take otherwise. I think this is exactly the argument that many have against such a device.

I have no strong opinion either way, but I'd love to see a complete rundown of every single time one has been deployed. I suspect that there have been at least a few cases where deployment was the wrong decision and led to a "non-save".
Steve

Single engine mountain flying is not "too" dangerous. It is more dangerous.
I will fly over the rockies during the day, but my choice is not to at night. That doesn't mean it is "too" dangerous to do it at night, only that I draw the line at that particular point. Others may draw the line completely differently.
If I did fly over the rockies at night, and if I did loose the motor and die, the mishap would not be concluded as pilot error. It would be mechanical failure. That is an important distinction that is much different from a VFR into unintentional IFR, running out of fuel, etc.
What I am saying, true only for me and my personal limits, is that having a chute would tip the balance in terms of survivability so that I would be willing to cross the rockies at night. I break it down like this:
-I have around 1200 hours and haven't had a motor quit yet. some of those were rentals which were not exactly maintained to the highest standards. My conclusion is that motor stoppages don't happen often.
-I maintain my airplane properly so there is a low probability my engine will quit in flight - ever
-At 17,500 feet, the power output of the engine is very low, reducing even further the likelihood of failure
-A likely scenario is that the last hour of the 6 hour trip would be flown at night. 1/6 of the time, 1/6 of the risk for that trip
-Of that one hour, brief periods of time would be over terrain not survivable with the chute, lets say 10 minutes.

So, with the chute, the motor would need to fail during those 10 minutes of the 360 minute trip. Or, another way of looking at it, precisely during those 10 minutes of the total 72,000 minutes I have flown so far. It is possible, but does not seem probable.

The risk is extremely low without the chute. More important, doing it with the chute is not taking a risk that I "wouldn't/shouldn't". With the chute, it is not the same risk. The chute modifies the risk.

Again, it is very analogous in some ways to twin engine flight. There are plenty of single engine (in twin aircraft) situations that are not survivable, but having that second engine modifies the risk so that some activities considered unacceptable for single engine, are considered acceptable for multi engine.
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  #27  
Old 04-22-2008, 04:20 PM
steveKs. steveKs. is offline
 
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Why not just strap on a parachute for the night xings over the mountains. I am thinking a parachute would be even more of a safety device than the BRS in the event of a onboard fire.
Leave the parachute at home for the 'more' safe flights and save the couple pounds of useful load.

I am not sure how my wife would react to me being 'chuted up' .....and her not..
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  #28  
Old 04-22-2008, 04:25 PM
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InsideOut InsideOut is offline
 
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This thread is becoming more entertaining than those about primer!
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  #29  
Old 04-22-2008, 04:25 PM
azav8or azav8or is offline
 
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Default Referring to the original question...

Could a BRS be put on a -12 due to regs if Van didn't do it first?

Thanks, Joe
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  #30  
Old 04-22-2008, 04:46 PM
SHIPCHIEF SHIPCHIEF is offline
 
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I'm wondering when the FAA will make them mandatory with automatic deployment criteria and simultaneous ELT start.
Oh, and Airbags in the cockpit too.
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