Cirrus down in Truckee

eman1200 said:
sheesh, ANOTHER cirrus down?
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You see a lot of Cirrus accident because there are a LOT of Cirruses.
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This ignores utilization rate, but one can probably assume the typical Cirrus flies more than the typical ~50-year-old 172. There are, overall about four times as many Cessna 172s as Cirruses, but there have been almost twice as many Cirruses built than new-production 172s.

Ron Wanttaja
 
I grew up at Lake Tahoe and still live in the area. I don't know if the engine quit, but every year we see density altitude accidents at Truckee and South Lake Tahoe. It is hard to appreciate how much performance you lose on a hot summer day here.
 
DA today at my home drome (KFLY) was 10,280. Temp was 95 F. Even now, 10:00 p.m., with temp = 75 F the DA is 9126. So we all need to watch the POH charts!
 
..did you guys see the airport statement release?

..of note:
"No fire resulted; no measurable fuel was spilled"

pure speculation, but SR20 (already grossly under powered, pathetic trash Cirrus should never have built) at a crazy high hot DA day with two people.. cutting it a little close with fuel for weight? .."it's a bit under tabs, but you can't trust the gauges, we should be fine for a few touch and goes in the pattern, we should stay light" <-I can practically hear that conversation

I HOPE not.. but if this is fuel related that's just disgraceful at this point.

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From what I'm reading on COPA, looks like it was on departure. The chute was pulled, but they may not have been high enough over the ground for full effect.

It was a hot and high, with a 7,800' DA. They crashed only 1/2 mile away after take-off. :(
 
wayne said:
From what I'm reading on COPA, looks like it was on departure. The chute was pulled, but they may not have been high enough over the ground for full effect.

It was a hot and high, with a 7,800' DA. They crashed only 1/2 mile away after take-off. :(
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Might have been better off flying it down. But I wasn't there, not criticizing, just observing.
 
Salty said:
Might have been better off flying it down. But I wasn't there, not criticizing, just observing.
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At that altitude, and with marginal power of the SR20 I would expect this to be a stall spin accident. Chute deployment at that AGL and speed is probably not very effective but better than nothing.
The chute starts to slow the plane down very quickly even if not fully deployed.with the nose down attitude of the plane the chute did not fully deploy and mqybe the stall was not recoverable.

Tim

Sent from my HD1907 using Tapatalk
 
tspear said:
I would expect this to be a stall spin accident
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This was my guess. I think the accident happened somewhere around the turn to crosswind or crosswind to downwind turn. The plane coming to rest upside down is a clue. Either that or fuel starvation, the lack of any evidence of spilled fuel from a plane sitting upside down is eerie

The SR20 is sluggish at sea level with one person it in. I can't imagine what it must be like on a hot day at elevation
 
Tantalum said:
This was my guess. I think the accident happened somewhere around the turn to crosswind or crosswind to downwind turn. The plane coming to rest upside down is a clue.
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That's a simulated image accompanying the ATC audio. Photos from the scene show the aircraft upright but everything crushed forward of the firewall.
 
flightwriter said:
That's a simulated image accompanying the ATC audio. Photos show the aircraft upright but everything crushed forward of the firewall.
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wow.. okay. That's on me then. Silly me for assuming the video was remotely descriptive of the accident. I forgave the no flap take off and the incorrect type, but that's pretty misleading to put it upside down when in fact it is not. Thanks for the clarification.
 
From the Facebook page: Aviation Accidents / This Day in History This is a good source for seeing accidents, but I can tell you there are so many accidents each day that I wouldn't hear of otherwise, it can be overwhelming.

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flightwriter said:
Photos from the scene show the aircraft upright but everything crushed forward of the firewall.
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That is normal. When the chute is deployed, the airplane will be in a nose down position. Theoretically, if they reached 500', which I would expect a cirrus to do by the end of the runway, the chute should have fully deployed.

I don't remember the descent fpm after deployment, but I do remember seeing it and thing it was pretty high.
 
im going to put all my thoughts about the cirrus aside, and just say this one is puzzling because if the chute deployed as it appears to have, given the pictures of the wreckage it appears that it should not have been a fatal accident.
 
unsafervguy said:
im going to put all my thoughts about the cirrus aside, and just say this one is puzzling because if the chute deployed as it appears to have, given the pictures of the wreckage it appears that it should not have been a fatal accident.
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I think the issue will be, if the chute was pulled, the altitude which it was pulled. 500 or 600 feet is considered the minimum depending on the model. That said, if you are 400 feet and just entered a spin, then pulling is the correct thing to do.

It doesn't take much impact to kill someone, the Cirrus is designed to land flat after a chute pull. It takes a little while for the chute to deploy, the aircraft is designed to be nose down during this process. After the chute is properly deployed, the airplane goes from nose down to a level flat attitude via magic or some type of sorcery.

If the chute is pulled too close to the ground, the airplane can hit nose first, eliminating some of the cushioning devices from working.
 
Just because you are low, and in an underpowered airplane doesn't mean you have to enter a spin! Fly the airplane! If it took off and was out of ground effect, I think it could fly level.
 
Wagondriver said:
Just because you are low, and in an underpowered airplane doesn't mean you have to enter a spin! Fly the airplane! If it took off and was out of ground effect, I think it could fly level.
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Unfortunately stall spin accidents are a huge problem in general aviation. I know people don't like Dan Gryder, but he is pushing this problem by pointing out issue in primary training.

Also, the 20 is hardly underpowered. That model was 200 hp, the newer ones with the Lycoming are 215 hp, I believe both will outclimb most trainers, and they are pretty fast for what they are. I was in a new 20 today and it was tooling along at 150 knots true, 5,500 feet. 75% power.
 
Some climb figures for reference from the POH, this is an older Cirri, but it should be closer to similar

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Truckee is at 6K.. it was probably close to 30*C when they flew.. so they'd have been squarely in that sub 500 range on the graph. Not a death sentence. But a regime where you need to pitch down to keep the airspeed in a happy place

If this really does turn out to be a stall/spin accident that's going to be really frustrating. These accidents are 100% preventable.
 
Tantalum said:
Some climb figures for reference from the POH, this is an older Cirri, but it should be closer to similar

View attachment 97356

Truckee is at 6K.. it was probably close to 30*C when they flew.. so they'd have been squarely in that sub 500 range on the graph. Not a death sentence. But a regime where you need to pitch down to keep the airspeed in a happy place

If this really does turn out to be a stall/spin accident that's going to be really frustrating. These accidents are 100% preventable.
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You have to be patient in a 20, they will climb, but they will heat up too if it's warm so you need to get clear of obstacles and transition into a cruise climb as soon as you can. I imagine in places like Truckee, that means plan your climb route carefully.

I'm pretty sure 2014 20s have esp, which should make it pretty hard to stall, never mind spin. But who knows.
 
PaulS said:
It doesn't take much impact to kill someone, the Cirrus is designed to land flat after a chute pull. It takes a little while for the chute to deploy, the aircraft is designed to be nose down during this process. After the chute is properly deployed, the airplane goes from nose down to a level flat attitude via magic or some type of sorcery.

If the chute is pulled too close to the ground, the airplane can hit nose first, eliminating some of the cushioning devices from working.
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Not magic, time delay fusing and line cutters delaying the re-pitch as the canopy inflates. See Cirrus own literature on the sequence, which I've snapshot here:
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This is why pulling too low can kill you, where not pulling at all at the same altitude may not. You are forced into a nose-low position until snub line severing, and away from the benefit of the designed airframe energy absorption attitude (gear and seats in particular). Until the snub line severs, you're eating the engine at 1700fpm. That's fatal, just like when people stall at 30 feet and the pitching moment traditional unswept wing airplanes incur put them engine to mouth.

The people who believe there is no opportunity cost to pulling low misunderstand the way the BRS design was meant to absorb energy.
 

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hindsight2020 said:
Not magic, time delay fusing and line cutters delaying the re-pitch as the canopy inflates. See Cirrus own literature on the sequence, which I've snapshot here:
View attachment 97379
This is why pulling too low can kill you, where not pulling at all at the same altitude may not. You are forced into a nose-low position until snub line severing, and away from the benefit of the designed airframe energy absorption attitude (gear and seats in particular). Until the snub line severs, you're eating the engine at 1700fpm. That's fatal, just like when people stall at 30 feet and the pitching moment traditional unswept wing airplanes incur put them engine to mouth.

The people who believe there is no opportunity cost to pulling low misunderstand the way the BRS design was meant to absorb energy.
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Magic and sorcery is much easier to type than all that. ;)

There have been successful low altitude pulls, but all your juju has to be just right. Or probably better explained, your energy state and attitude, say, flying along straight and level in a gliding descent, versus incipient or developed spin.
 
hindsight2020 said:
Until the snub line severs, you're eating the engine at 1700fpm.
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And with a low deployment, isn't the aircraft swinging more under the canopy? Coupling an ill-timed downward swing with a nose-low attitude at impact could be an even nastier scenario.
 
I would think the high DA would also affect the chute inflation height.

Sorry, did not read all responses.
 
PaulS said:
Also, the 20 is hardly underpowered. That model was 200 hp, the newer ones with the Lycoming are 215 hp, I believe both will outclimb most trainers…
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Over on the Cirrus forum they’re affectionately referred to as UPDT’s. Under Powered Death Traps.

But I think that comes largely from comparing them to SR22’s. Since climb rate is largely dependent on extra hp, having 100hp or so less definitely makes a big difference.

But thinking back, I don’t think their climb performance is markedly different from a C150 or a Cherokee 140 or a Grumman Traveler at gross. Perhaps because of the sleekness and all the doodads SR20 owners are lulled into expecting better performance than is actually available. And thinking about it now, even if they climb at about the same rate as the above mentioned planes, they’re doing it at what looks like about 20 kts faster, resulting in a much shallower climb angle. In the foothills of the Appalachians where I live now, which aren’t exactly the Rockies, there are lots of small airports with decent-sized runways but rising terrain in all or most quadrants. I can easily see an SR20 pilot getting in trouble at these without very careful planning.
 
The sr20 with io-390 I flew in climbed far better than a Cherokee 140 or Cessna 150. I’m sure it’s pathetic compared to the 22, but it’s not that bad.
 
FastEddieB said:
Over on the Cirrus forum they’re affectionately referred to as UPDT’s. Under Powered Death Traps.

But I think that comes largely from comparing them to SR22’s. Since climb rate is largely dependent on extra hp, having 100hp or so less definitely makes a big difference.

But thinking back, I don’t think their climb performance is markedly different from a C150 or a Cherokee 140 or a Grumman Traveler at gross. Perhaps because of the sleekness and all the doodads SR20 owners are lulled into expecting better performance than is actually available. And thinking about it now, even if they climb at about the same rate as the above mentioned planes, they’re doing it at what looks like about 20 kts faster, resulting in a much shallower climb angle. In the foothills of the Appalachians where I live now, which aren’t exactly the Rockies, there are lots of small airports with decent-sized runways but rising terrain in all or most quadrants. I can easily see an SR20 pilot getting in trouble at these without very careful planning.
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The faster speed is a good point Eddie, Tantalum posted a climb chart on the Continental 20, the Lycoming climbs better.

A C150M climbs at 280 fpm at 8000 20C, 63 kias, I assume at full gross weight. The Conti 20, per the chart in Tantulum's post climbs at 390 fpm, 8000 ft, 20C , 82 kias full gross.

So the Cirrus climb gradient (assuming I did the math correctly) is 285 feet per mile. The 150 is 267 feet per mile. Pretty similar I guess.

I'm not sure this accident was a climbing problem though, seems more like a maintaining airspeed issue, or as some have alluded to, maybe a fuel starvation issue.


Edit: Oh, and the doo dad comment you make may be plausible, but that is an airmanship issue, not an airplane issue.

The C150M climb chart it page 72 in this link.

CESSNA_150_POH.pdf (cpaviation.com)
 
I believe 1700 fpm is the descent rate when the chute is fully deployed - to me, that seems really fast. The impact is supposed to be compensated for by the crumple zone in the seats, which is why you never kneel on them. Perhaps someone violated that at one point or just over time and some hard landings, the left seat was compromised.

Possible they weren't high enough. While the chute is deploying, it's held partially closed for the first 8 seconds or so by the ring on the rigging.
 
bflynn said:
I believe 1700 fpm is the descent rate when the chute is fully deployed - to me, that seems really fast. The impact is supposed to be compensated for by the crumple zone in the seats, which is why you never kneel on them. Perhaps someone violated that at one point or just over time and some hard landings, the left seat was compromised.

Possible they weren't high enough. While the chute is deploying, it's held partially closed for the first 8 seconds or so by the ring on the rigging.
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Knees in the seats will compromise them, sitting on them won't. The seats are part of the system, but the landing gear plays a big role too.
 
I just noticed that Truckee has a tower and Tahoe doesn't. It used to be the opposite.
 
bflynn said:
I believe 1700 fpm is the descent rate when the chute is fully deployed - to me, that seems really fast. The impact is supposed to be compensated for by the crumple zone in the seats, which is why you never kneel on them. Perhaps someone violated that at one point or just over time and some hard landings, the left seat was compromised.

Possible they weren't high enough. While the chute is deploying, it's held partially closed for the first 8 seconds or so by the ring on the rigging.
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Still, that's under 20 mph, with nice landing gear and seats to absorb the crunch.
 
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