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Midair Collision over Denver

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Re: Midair Collision over Denver

#141

Post by sio8ohPi »

jmpman wrote: post #135
JohnJamesRambo wrote: post #88

Earlier quoted context omitted.

Thank you, I was so confused. I was thinking the pilot a genius for bringing and activating a parachute. Now I see it was just great design. > As of 1 May 2021, CAPS had been activated 122 times, 101 of which saw successful parachute deployment. In those successful deployments, there were 207 survivors and 1 fatality. No fatalities had occurred when the parachute was deployed within the certified speed and altitude p…

21 of 122 failed? That’s a concerning statistic. I’d expect closer to 99% success, not 82%. How many fatalities when the parachute failed to deploy? 100%? If so, then you have almost a 1/5 chance of dying when you engage the parachute?

Cirrus has a list of deployment events on their site. The failures mostly appear to be cases where the parachute was deployed too low.

https://www.cirruspilots.org/Safety/CAPS-Event-History?id=3

Re: Midair Collision over Denver

#142

Post by _ea1k »

sokoloff wrote: post #85
qayxc wrote: post #81

Earlier quoted context omitted.

> The weight is so critical that the 7-seat plane can realistically only seat 4-5 adults. I think you overlooked an important factor there. The plane was indeed designed to realistically seat 7 adults. The issue is that in the 50 years since the plane was originally designed, the average weight of adults (in the US) increased by about 18% [0] and the average adult woman today weighs as much as the average adult man i…

I find it very hard to agree that a PA-32 was "designed to realistically seat 7 adults". I don't think they even imagined 6 adults as a typical cabin load, but rather a max of 4 adults and 2 kids and a typical of 2 adults and 2-4 kids. It is one of the more roomy cabins among light singles, but every one of them that I see for listed for sale right now is configured with seating for only 6, which is great for 2 adult…

Yeah, its 7 seats in the same sense as the Tesla Model Y can be a 7 seater. Its technically true, but really only true if some of those people are small.

Even with FAA standard people it would be small for 7.

Re: Midair Collision over Denver

#143

Post by strogonoff »

osenthuortuh wrote: post #101
sillysaurusx wrote: post #93

Earlier quoted context omitted.

Did his wife survive?

The second link is the crash report. There were four occupants and only one fatality, so only he died. Looks like he tried to land in bad weather, descended before he could see the runway, and clipped some trees. Weather is an alarmingly common cause of accidents in general aviation.

> Weather is an alarmingly common cause of accidents in general aviation.

Or—to rewind the causal chain just a little further—pilot hubris, impatience and/or ignorance, which leads to weather being a factor in the first place. The choice to wing it and hope bad weather in the area will not affect you is the pilot’s.

From my shallow study of fatal and non-fatal GA accidents, there is hardly ever such a combination of life-or-death urgency and absence of alternative transportation options besides flying that could justify risking one’s own life and lives of one’s passengers by wilfully or accidentally ignoring weather forecast, and yet too often that appears to be the case.

It’s not a pleasure to talk about incidents like that, but “all plane crashes are pilot error” strikes me as a decent framing of the situation to adopt as a pilot when considering a risky flight.

Re: Midair Collision over Denver

#144

Post by fnordfnordfnord »

AdrianB1 wrote: post #94
cookguyruffles wrote: post #44

Earlier quoted context omitted.

Am I correct in saying after one usage, the parachute system generally needs replaced? I think I read this about Cirrus planes anyway

Yes. The parachute has a pyrotechnic deployment mechanism that is consumed; I never saw a BRS sold in separate components, so you need to replace the entire package. The 10 year shelf life is coming from the pyrotechnic charge and the parachute material, they both age.

You can buy the components separately but they won't usually be certified so that's only useful for EAA types and people like Mike Patey.

Re: Midair Collision over Denver

#145

Post by mannykannot »

elliekelly wrote: post #104
mannykannot wrote: post #76

Earlier quoted context omitted.

I completely agree, but for a more complete analysis, we would have to consider the fatality rate for the sort of crashes in which CAPS is employed. IIRC, Cirrus is now encouraging pilots to use CAPS in any engine failure with sufficient altitude for it to work, on account of the number of such accidents, in CAPS-equipped aircraft, where the pilot chose not to use it, and someone aboard was killed or seriously injure…

Are there any fees associated with an emergency landing like that? I imagine La Guardia runways are in pretty high demand but pilots have a culture that prioritizes safety above all else so I’d be curious which takes precedence.

Tangentially, one reason why Cirrus has been persuading pilots to use CAPS as soon as they get into difficulties is because it was suspected that pilots often chose not to do so (or delay until too late) because it was widely believed (and is true in most cases) that doing so totals the airplane - i.e. an economic disincentive to put safety first.

Re: Midair Collision over Denver

#146

Post by opwieurposiu »

jmpman wrote: post #135
JohnJamesRambo wrote: post #88

Earlier quoted context omitted.

Thank you, I was so confused. I was thinking the pilot a genius for bringing and activating a parachute. Now I see it was just great design. > As of 1 May 2021, CAPS had been activated 122 times, 101 of which saw successful parachute deployment. In those successful deployments, there were 207 survivors and 1 fatality. No fatalities had occurred when the parachute was deployed within the certified speed and altitude p…

21 of 122 failed? That’s a concerning statistic. I’d expect closer to 99% success, not 82%. How many fatalities when the parachute failed to deploy? 100%? If so, then you have almost a 1/5 chance of dying when you engage the parachute?

It's not 100%. In one of the flying mags you can read a story about how a VFR (not instrument rated) pilot got into the soup, lost attitude awareness, freaked out and pulled the chute lever. Nothing happens. While the pilot was yanking on the chute lever, taking hands off the stick let the aircraft's static stability take over and the plane flew out of the cloud by itself. The pilot then took over and landed in the usual manner.

Re: Midair Collision over Denver

#147

Post by wingspar »

strogonoff wrote: post #143
osenthuortuh wrote: post #101

Earlier quoted context omitted.

The second link is the crash report. There were four occupants and only one fatality, so only he died. Looks like he tried to land in bad weather, descended before he could see the runway, and clipped some trees. Weather is an alarmingly common cause of accidents in general aviation.

> Weather is an alarmingly common cause of accidents in general aviation. Or—to rewind the causal chain just a little further—pilot hubris, impatience and/or ignorance, which leads to weather being a factor in the first place. The choice to wing it and hope bad weather in the area will not affect you is the pilot’s. From my shallow study of fatal and non-fatal GA accidents, there is hardly ever such a combination of…

Another famous case of bad judgement resulting is JFK Jr. https://en.wikipedia.org/wiki/John_F._Kennedy_Jr._plane_cras...

Re: Midair Collision over Denver

#148

Post by azalemeth »

phkahler wrote: post #130
azalemeth wrote: post #33

Earlier quoted context omitted.

Indeed. Something else I'd like to point out is that it might seem easy to 'blame the Cirrus' pilot or them call out for inattention, but doing so by itself isn't helpful. Aviation is so safe partly because it has managed to turn a culture of blame into a culture of continuous improvement and shared learning: I'd be very surprised if the airport's procedures came out of this unmodified, for example.

>> I'd be very surprised if the airport's procedures came out of this unmodified, for example. I'm curious. The airport is at about 5900ft and they were at 6400. If that's AGL for them that seems like a long and high approach. If not, then they were going to do a 3 mile straight in at 500 feet AGL? Either interpretation doesn't fit my (limited, student) experience.

KAPA is indeed 5900 MSL, and those heights are also all MSL.

Looking at the FAA's charts, https://aeronav.faa.gov/d-tpp/2104/05715R17L.PDF, this combination of heights and distances isn't totally crazy -- I state without proof (and wait to be corrected!) that the approach is modified because it is a relatively high altitude airport and there may be quite steeply changing terrain underneath. I've never flown there (not even on X-plane) and I'm a low-hours UK person.

I haven't done the trig and meterological lookup to work out what their AGL altitude was on that day, but at the very least it's not crazy-wrong from the published chart...

Re: Midair Collision over Denver

#150

Post by tialaramex »

captainredbeard wrote: post #123
elliekelly wrote: post #99

Earlier quoted context omitted.

I’m not really sure how to ask what I want to ask, so apologies if this doesn’t make sense: Does the parachute only work if the plane is in a free fall? If the plane is gliding along and suddenly the engine goes out, for example, would pulling the chute work?

Well you wouldn’t pull the chute. The plane has lift when it has forward motion at a non stalling angle of attack. It would become a glider until reaching stall speed

No, you should probably pull the chute.

Yes you're gliding right now, but whilst that's better than just falling uncontrolled from the sky it's no guarantee you'll walk away.

Now if you're gliding... right towards a perfectly nice runway you were already lined up on then CAPS is likely the wrong call, not least because you may already be too low. But if you're just in the middle of nowhere then CAPS is much safer than hoping that's just a big empty grassy meadow you see ahead and doesn't have a thin, wheel-snagging ditch, or a barbed wire fence, or a dozen other obstacles that you wouldn't see until it's too late.

Even for a water landing, if you have never practised there are a lot of ways for putting a conventional plane down in the water to go badly, including flipping or breaking up the plane, whereas CAPS should just plonk you in the water, relatively gently, right side up, not great news, but very survivable.

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