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  #11  
Old 06-28-2009, 08:32 AM
JumpNurse JumpNurse is offline
 
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Quote:
Originally Posted by jrsites View Post
I'm interested in your thoughts on this. In what types of situations do you envision the "level" button being most effective?
This is of course from a student pilot with .6 hrs IFR and zero in a Cirrus, so keep that in mind. My thought were for all of the weather related accidents. Both IFR pilots getting in situations beyond their abilities and VFR pilots who, for whatever reason, find themselves in IMC. If they are aware enough to realize they are in trouble, this feature may buy them the time to regain situational awareness rather than spiraling into dirt because of no visual references. I don't think one should become device dependent, but even the most experienced aviator isn't above making an error. The vestibular system is a powerful beast that is hard to say no to even with the best instruments telling the real truth about your flight path.
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  #12  
Old 06-28-2009, 10:18 AM
Ron Lee's Avatar
Ron Lee Ron Lee is offline
 
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Default Level button/switch

Interesting. I was under the apparent mistaken perception that the normal reaction to anything non-nominal was to deploy the parachute.
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  #13  
Old 06-28-2009, 10:48 AM
John Clark's Avatar
John Clark John Clark is offline
 
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Quote:
Originally Posted by Ron Lee View Post
Interesting. I was under the apparent mistaken perception that the normal reaction to anything non-nominal was to deploy the parachute.
The max deployment speed for the parachute is 133 KIAS, so there are plenty of scenarios where the 'chute would fail instantly.

John Clark
RV8 N18U "Sunshine"
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  #14  
Old 06-28-2009, 04:03 PM
Danny7 Danny7 is offline
 
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cirrus, cessna (columbia) and anyone else that makes a composite 4 place factory plane will end up with a heavy plane. that will reduce performance. A kit plane can be as spartan as the owner wants it light, he is the only one he has to please.

seems to be a hard comparison to make, the factory built vs kit built AND sheet metal vs composite, at the same time.
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  #15  
Old 06-28-2009, 04:53 PM
roee roee is offline
 
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Quote:
Originally Posted by Ron Lee View Post
Interesting. I was under the apparent mistaken perception that the normal reaction to anything non-nominal was to deploy the parachute.
I'm pretty sure this comment was tongue in cheek, right? I would think that pulling the chute is an option of last resort, like in an unrecoverable spin, or major structural or control systems failure, or an engine out over terrain that would preclude a survivable landing. The level button sounds like a valuable feature for situations like inadvertent flight into IMC, or spatial disorientation at night, or any other unexpected loss of visual reference. And unlike the chute, it could save your skin and the airplane's.

Disclaimer: I've never flown a Cirrus nor any airplane that has had a BRS chute nor a level button. But they both sounds like good ideas.
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  #16  
Old 06-28-2009, 04:54 PM
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flyeyes flyeyes is offline
 
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Quote:
Originally Posted by John Clark View Post
The max deployment speed for the parachute is 133 KIAS, so there are plenty of scenarios where the 'chute would fail instantly.

John Clark
RV8 N18U "Sunshine"
KSBA

Actually just one scenario, the very high speed deployment ;-)

There has been at least one successful deployment at well over Vne. Admittedly the plane was probably light as there was only one on board.

BRS deplyment

The ntsb report is a little vague, but the pilot was a very active member of the Cirrus list and posted a lengthy account of the accident which was chilling. Basically he was near the end of an IFR flight, passed out and awoke to find himself confused and in a high-speed dive. He had difficulty processing the instruments, but the airspeed tape was red. He pitched up and deployed the parachute because he was unsure what was happening and didn't know if he would lose consciousness again. It turns out he had a previously undiagnosed brain tumor.

This accident is also quite interesting. This was a high altitude IMC upset/loss of control resulting in a very rapid descent.

The pilot lost control and became disoriented. He had erroneous airdata because of icing and was attempting to regain control when the ground proximity warning (gps based) in the Garmins activated. He activated the parachute and apparently ground impact occurred within seconds of activation. The pilot was very surprised that he had lost that much altitude in such a short time.

There was one accident (unfortunately no survivors) near Lake Tahoe that also began as icing, high speed descent, and a failed CAPS deployment. Radar data suggested a very high speed descent, with a vertical speed estimated 100+knots over Vne.
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  #17  
Old 06-28-2009, 10:02 PM
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rene@felker.com rene@felker.com is offline
 
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The Truetrak AP will do that ........just turn it on, it flys the current coarse and climb or decent.........has a AS limit that can be set and will not climb at a slower speed. On my list of "other" test I would like to do during phase II is to go out and do some unusual attitudes with my instructor and activate the AP and see if it makes the situation better or worse......
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  #18  
Old 06-28-2009, 10:15 PM
jrsites jrsites is offline
 
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Quote:
Originally Posted by JumpNurse View Post
This is of course from a student pilot with .6 hrs IFR and zero in a Cirrus, so keep that in mind. My thought were for all of the weather related accidents. Both IFR pilots getting in situations beyond their abilities and VFR pilots who, for whatever reason, find themselves in IMC. If they are aware enough to realize they are in trouble, this feature may buy them the time to regain situational awareness rather than spiraling into dirt because of no visual references. I don't think one should become device dependent, but even the most experienced aviator isn't above making an error. The vestibular system is a powerful beast that is hard to say no to even with the best instruments telling the real truth about your flight path.
I have zero experience in a Cirrus, either. I do, however, have G1000 experience. I do see how an altitude and heading hold feature could be useful in an inadvertent IMC situation when you're trying to talk on the radio, fly the airplane, navigate, etc.

What I don't quite understand is how a "level" button is any different or does anything better than simply pressing "ALT" and "HDG" on you autopilot controler.

I'm not instrument rated, but even flying just VFR, my standard practice is to set the altitude bug to reflect my assigned or desired altitude, and the heading bug to reflect my assigned or desired heading, whether I have the autopilot engaged or not. That being the case, simply pressing ALT and HDG should have the same effect as pressing the LVL button, no? Yes, it's two button presses instead of one, and it assumes you have your bugs set to your current altitude and heading, but I can't foresee too many situations where the LVL button is going to accomplish something that can't be accomplished by the equipment that was already in the cockpit prior to the advent of the LVL button.

Actually, my guess is that most people flying an airplane in the Cirrus class have the autopilot engaged from 500 ft. AGL after takeoff until final approach. So there again, I can't imagine a situation where the LVL button does anything for you; you're likely to be ON the autopilot already when encountering inadvertent IMC, etc.

All in all, it's an example of Cirrus adding a certain measure of automation to the cockpit. And automation can contribute to increased safety, when used properly. It certainly doesn't make the cockpit LESS safe. But I am having a hard time seeing it as anything more than a gimmick at this point, as I just can't imagine any real world scenario where the LVL button is going to accomplish something you couldn't do with the same old autopilot buttons that existed in the previous Cirrus iteration.

Anyone with more experience in a Cirrus who can add any comments?
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  #19  
Old 06-28-2009, 10:31 PM
jrsites jrsites is offline
 
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Quote:
Originally Posted by roee View Post
Disclaimer: I've never flown a Cirrus nor any airplane that has had a BRS chute nor a level button. But they both sounds like good ideas.
The question of whether a parachute is a good idea or not is somewhat like the question "Have you stopped cheating on your taxes?" A simple yes or no does not sufficiently answer the question.

An airplane with a parachute in it IS incrementally safer than one without a parachute, simply because it has one more option for relatively safe return to earth in the event something "non-nominal" (to borrow Ron's phrase) occurs.

What is interesting to me, though, are the number of people who assume that a parachute in the airplane automatically means that there are now NO bad situations which cannot be gotten out of. This is wrong.

When do the largest majority of accidents happen? In the takeoff and landing phases of flight. The parachute will not save your hide in a departure stall or stall/spin on turn to final. Nor will it keep you from busting minimums and flying into the approach lights. Or from failing to do your density altitude calculations on that hot summer day.

The reality is that the parachute is likely constrained to a very limited "window" of operation (airspeed limits, bank angles, altitudes, etc.). Now, if you were to overlay the types of "non-nominal" events that might occur within that window, my guess is that you're looking at a relatively small number of situations in which the parachute becomes a true difference-maker.

Am I saying the parachute is worthless? No. Again, it doesn't make the airplane LESS safe. Heck, if I had the choice of two airplanes that flew and performed identically, one with a parachute and one without, I'd take the one with the parachute. I'm just saying that I don't believe the parachute is the panacea of safety it appears to be on first blush.
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  #20  
Old 06-28-2009, 11:03 PM
John Clark's Avatar
John Clark John Clark is offline
 
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Quote:
Originally Posted by jrsites View Post
The question of whether a parachute is a good idea or not is somewhat like the question "Have you stopped cheating on your taxes?" A simple yes or no does not sufficiently answer the question.

An airplane with a parachute in it IS incrementally safer than one without a parachute, simply because it has one more option for relatively safe return to earth in the event something "non-nominal" (to borrow Ron's phrase) occurs.

What is interesting to me, though, are the number of people who assume that a parachute in the airplane automatically means that there are now NO bad situations which cannot be gotten out of. This is wrong.

When do the largest majority of accidents happen? In the takeoff and landing phases of flight. The parachute will not save your hide in a departure stall or stall/spin on turn to final. Nor will it keep you from busting minimums and flying into the approach lights. Or from failing to do your density altitude calculations on that hot summer day.

The reality is that the parachute is likely constrained to a very limited "window" of operation (airspeed limits, bank angles, altitudes, etc.). Now, if you were to overlay the types of "non-nominal" events that might occur within that window, my guess is that you're looking at a relatively small number of situations in which the parachute becomes a true difference-maker.

Am I saying the parachute is worthless? No. Again, it doesn't make the airplane LESS safe. Heck, if I had the choice of two airplanes that flew and performed identically, one with a parachute and one without, I'd take the one with the parachute. I'm just saying that I don't believe the parachute is the panacea of safety it appears to be on first blush.
I agree completely. The parachute system has its points but it isn't the panacea that Cirrus' marketing department makes it out to be.

John Clark
RV8 N18U "Sunshine"
KSBA
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