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Re:Midair Collision over Denver by nickcw on Thursday May 13, 2021 @03:13AM (#27139288)
Just in case anyone (like me) is thinking - wait did that aeroplane have a parachute?

From:

https://en.m.wikipedia.org/wiki/Cirrus_Airframe_Parachute_Sy...

The Cirrus Airframe Parachute System (CAPS) is a whole-plane ballistic parachute recovery system designed specifically for Cirrus Aircraft's line of general aviation light aircraft including the SR20, SR22 and SF50. The design became the first of its kind to become certified with the FAA, achieving certification in October 1998, and as of 2014 was the only aircraft ballistic parachute used as standard equipment by an aviation company.

Re:Midair Collision over Denver by t0mas88 on Thursday May 13, 2021 @03:45AM (#27139461)
The more generic system is called BRS, Ballistic Recovery Systems. They deliver this as an option for many small aircraft and it's popular for experimental / home built aircraft.

One downside of the systems is that they typically have a maximum lifespan of 10 years while airframes last 50+ years. So every 10 years there is a large maintenance cost to replace/renew the parachute system. Much less an issue for a $ 800k Cirrus SR22 (like the one in this incident) than for a $ 30k old Cessna.

Re:Midair Collision over Denver by cookguyruffles on Thursday May 13, 2021 @05:27AM (#27140205)
Am I correct in saying after one usage, the parachute system generally needs replaced? I think I read this about Cirrus planes anyway
Re:Midair Collision over Denver by bbojan on Thursday May 13, 2021 @05:29AM (#27140223)
I believe the whole airplane needs to be replaced after BRS use.
Re:Midair Collision over Denver by ahartmetz on Thursday May 13, 2021 @05:38AM (#27140285)
It may sound pointless unless you consider that the pilot will not need to be replaced.
Re:Midair Collision over Denver by Leherenn on Thursday May 13, 2021 @05:55AM (#27140378)
There's the issue that in many cases people tried to save the airframe rather than activate the parachute, knowing the aircraft was likely to be written off, and died doing so. It the same when the pilot is equipped with a parachute.
Re:Midair Collision over Denver by toss1 on Thursday May 13, 2021 @11:25AM (#27143174)
Yes, and this happens also in many other arenas. I've only done a bit of flying, but in my experience in speed sports such as Downhill ski racing and auto racing, you must be mentally able to switch your goals in a fraction of a second, from [win the race] to [save the run] to [save your life], without hesitation.

Sometimes you succeed in [save your life] and are still on-track / on-piste pointing in the right direction and are back to [win the race] in the space of a few seconds. Other times, you are on the sidelines, and hopefully not on the way to the field clinic.

But the switch in perspective must fully committed and absolutely not include [save the equipment], which is replaceable, even custom one-off gear. Anything else is over-constraining the problem and inviting disaster.

Re:Midair Collision over Denver by toss1 on Friday May 14, 2021 @09:37AM (#27154148)
Beyond that, sometimes the [save your life] mode should include [sacrifice the equipment to save your life].

I remember an incident from one of my auto racing instructors. In a race, coming into a downhill turn (Diving turn at Lime Rock) at triple-digit mph, he found that he had no brakes. So he very rapidly pushed in the clutch, redlined the engine, grabbed 2nd gear, and popped the clutch with some steering input. The result was that he spun the car with enough control to crash into the barriers with the back end first. It was the end of that Porsche, but it would have been anyway, and he walked away.

Or, another guy I knew who was at logging school, 150' up pruning in a pine tree, realized that it was getting way out of balance and was about to get violent. He cut to just the right point, then threw the multi-$1000 chainsaw as far as he could away from him, and hung on for life to his harness and tree strap as the tree whipped back and forth until the oscillations dampened. He got kind of beat up, but climbed down and walked away.

It's key to be ready to completely change your mindset in a flash.

Re:Midair Collision over Denver by karlkatzke on Thursday May 13, 2021 @10:12AM (#27142293)
At the point a pilot is considering declaring an emergency, they should do so. Once they have declared an emergency, the insurance company owns the airplane, and the pilot should be focused on preserving as many lives as possible. This is as true for a mechanical emergency like a gear up landing as it is for every other kind of emergency.
Re:Midair Collision over Denver by thesh4d0w on Thursday May 13, 2021 @12:24PM (#27143996)
That's assuming you have in motion insurance on your aircraft. I don't on my 152, the plane is worth so little we'd cover the airframe cost in 7 years of insurance payments.
Re:Midair Collision over Denver by sokoloff on Thursday May 13, 2021 @06:36AM (#27140611)
This is indeed the early experience with BRS, which has been substantially addressed via training which started with some complex scenario-based messaging and later evolved to a more simplified “pull early, pull often” which has resulted in a bias in a better direction for human safety.
Re:Midair Collision over Denver by MaxBarraclough on Thursday May 13, 2021 @10:25AM (#27142405)
What's the risk to the people below?

I'm reminded of a 2011 airshow crash of a Red Arrows T1 jet which, at least according to this account, [0] may have involved the pilot heroically making the decision not to personally eject, but to crash the aircraft away from crowded areas, perishing as a result. Of course, the aircraft itself had no parachute, unlike a Cirrus. (Also, I'm uncertain if that account of the incident is consistent with later investigation. The relevant quote is not from any investigation, but from a politician.)

[0] https://www.bbc.co.uk/news/uk-england-dorset-14838982

Re:Midair Collision over Denver by cameldrv on Thursday May 13, 2021 @12:01PM (#27143656)
There’s a huge difference in the danger to those on the ground between an 15000 lb fighter jet going hundreds of mph and a small 3000 lb airplane descending at about 15 mph (plus the wind speed).

It’s possible that the Cirrus could hurt or kill someone but I don’t think it’s happened in the about 100 parachute activations so far.

Re:Midair Collision over Denver by MaxBarraclough on Thursday May 13, 2021 @01:03PM (#27144513)
> There’s a huge difference

Of course there is, that's the reason I emphasised it.

> I don’t think it’s happened in the about 100 parachute activations so far

That's good, although there could be a selection effect there: pilots might be more hesitant to deploy it if they think the falling aircraft could do harm.

Re:Midair Collision over Denver by EricE on Thursday May 13, 2021 @12:19PM (#27143920)
>What's the risk to the people below?

A lot less than from a plane traveling at terminal velocity!

Re:Midair Collision over Denver by agloeregrets on Thursday May 13, 2021 @03:25PM (#27146239)
I mean, would you rather the plane crash at 30mph at a chosen point or at 200mph wherever it leads?
Re:Midair Collision over Denver by sokoloff on Thursday May 13, 2021 @08:18PM (#27149172)
Once you’re under chute, the airplane is picking the arrival spot.
Re:Midair Collision over Denver by agloeregrets on Friday May 14, 2021 @08:13AM (#27153374)
Yes, but you get to choose when you pull the chute, whereas if you lose say, your elevator control, You don't get any choices here.
Re:Midair Collision over Denver by nopzor on Thursday May 13, 2021 @05:59AM (#27140401)
yes, i think the way i’ve heard it pitched is that deploying the parachute will result in “a bad day for the insurance company, and a great day for the pilots and passengers”
Re:Midair Collision over Denver by miked85 on Thursday May 13, 2021 @05:47AM (#27140342)
> Cirrus originally thought that the airframe would be damaged beyond repair on ground-impact, but the first aircraft to deploy (N1223S) landed in mesquite and was not badly damaged. [1]

[1] https://en.wikipedia.org/wiki/Cirrus_Airframe_Parachute_Syst...

Re:Midair Collision over Denver by stevehawk on Thursday May 13, 2021 @11:23AM (#27143146)
they're almost always totaled by the insurance company. Easier than risking that they missed a hairline fracture somewhere and have the plane go down again.
Re:Midair Collision over Denver by mc32 on Thursday May 13, 2021 @08:18AM (#27141249)
Not necessarily. Frames can be repaired. Frame repairs and overhauls are common. If the damage is too extensive and expensive then you use it for parts.
Re:Midair Collision over Denver by AdrianB1 on Thursday May 13, 2021 @08:59AM (#27141564)
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.
Re:Midair Collision over Denver by fnordfnordfnord on Thursday May 13, 2021 @10:32AM (#27142490)
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 by jaywalk on Thursday May 13, 2021 @08:30AM (#27141343)
The parachute system will need to be completely replaced after usage no matter what. Activating the parachute involves firing a small rocket motor to pull it out quickly.
Re:Midair Collision over Denver by JohnJamesRambo on Thursday May 13, 2021 @08:40AM (#27141410)
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 parameters

Re:Midair Collision over Denver by ssully on Thursday May 13, 2021 @02:04PM (#27145222)
For those curious about seeing it in action: https://www.youtube.com/watch?v=gBCUQlF3MMU
Re:Midair Collision over Denver by captainredbeard on Thursday May 13, 2021 @10:01AM (#27142182)
It’s a “marquee feature” of buying a Cirrus, he didn’t just wake up and pack a chute
Re:Midair Collision over Denver by jmpman on Thursday May 13, 2021 @10:19AM (#27142364)
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?
Re:Midair Collision over Denver by sio8ohPi on Thursday May 13, 2021 @10:29AM (#27142448)
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 by opwieurposiu on Thursday May 13, 2021 @10:37AM (#27142555)
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 by bananabreakfast on Thursday May 13, 2021 @01:36PM (#27144890)
That is not a correct interpretation of that statistic.

The parachute has never "failed" in any engineering sense. The stat is taking into account all deployments, including those well outside of the deployment envelope, such as not enough altitude or too much velocity. No one can expect any parachute to deploy if you're too close to the ground.

Within the envelope of deployment, the statistic says it has a 100% success rate.

Re:Midair Collision over Denver by stevehawk on Thursday May 13, 2021 @11:25AM (#27143167)
the chute has deployment parameters (altitude, airspeed of plane, etc) that aren't always met by the pilot in an emergency.
Re:Midair Collision over Denver by jessriedel on Thursday May 13, 2021 @12:25PM (#27144016)
If the pilot flies into terrible weather or gets into an uncontrolled spin, it's not reasonable to expect the chute to deploy correctly and save the situation.
Re:Midair Collision over Denver by londons_explore on Thursday May 13, 2021 @09:40AM (#27141938)
They are some impressive numbers, but to really compare you need an expert looking at each situation and estimating the likely outcome had the CAPS system not been installed.
Re:Midair Collision over Denver by selectodude on Thursday May 13, 2021 @10:05AM (#27142228)
Most GA pilots are awful so it's a pretty safe bet that CAPS saved lives.
Re:Midair Collision over Denver by maweki on Thursday May 13, 2021 @03:29AM (#27139377)
I was wondering whether there was a mix-up in the crew count, as one pilot with a parachute saves two people and a one-person crew lands the plane.

This mostly clears it up.

Re:Midair Collision over Denver by Grustaf on Thursday May 13, 2021 @04:01AM (#27139586)
My less charitable reading was that the pilot abandoned the Cirrus on a parachute, but then it seemed like the plane landed…
Re:Midair Collision over Denver by tialaramex on Thursday May 13, 2021 @04:33AM (#27139825)
Pilots of planes with CAPS are (now) taught to pull the chute if anything goes wrong inside the profile (low enough speed, far enough above ground) where the chute is designed to work. The aeroplane is insured, you can buy a new one. Even if the pilot and all passengers are insured you can't buy new ones.

They changed this because it turns out that the same phenomenon that leads to private pilots taking undue risks in the rest of flight ("Get-there-itis") also makes them reluctant to pull the chute even when it's clearly their best option. Pilots who clearly couldn't reach a safe landing spot, yet had working CAPS would dig themselves (and their passengers) a grave rather than just pull the handle. So teaching them to start by assuming they'll pull the chute and only then considering whether there are other options reduces the fatality rate.

Re:Midair Collision over Denver by elliekelly on Thursday May 13, 2021 @09:21AM (#27141756)
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?
Re:Midair Collision over Denver by throw0101a on Thursday May 13, 2021 @09:34AM (#27141877)
There is a maximum speed that the system can handle:

> Four CAPS deployments occurred successfully at higher speeds, 168, 171, 187 and 190 knots indicated airspeed, and one deployment failed at an airspeed estimated at over 300 knots airspeed.

* https://www.cirruspilots.org/Safety/What-Is-CAPS

Anything lower than that will forward-motion stop the aircraft. AFAICT, there is a need for 2000' (650m) of altitude above the ground for the system to deploy in time to be useful (slow descent).

Re:Midair Collision over Denver by DarmokJalad1701 on Friday May 14, 2021 @01:17AM (#27150976)
> AFAICT, there is a need for 2000' (650m) of altitude above the ground for the system to deploy in time to be useful

Official Cirrus guidelines include verbalizing "CAPS is available" when crossing 600ft AGL during climb-out.

Source: I fly an SR22.

Re:Midair Collision over Denver by captainredbeard on Thursday May 13, 2021 @10:04AM (#27142209)
Even then, they recommend pulling the chute anyway because it can reduce velocity if it’s still above nominal “touchdown” speed
Re:Midair Collision over Denver by captainredbeard on Thursday May 13, 2021 @10:03AM (#27142200)
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
Re:Midair Collision over Denver by tialaramex on Thursday May 13, 2021 @10:49AM (#27142682)
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.

Re:Midair Collision over Denver by jrockway on Thursday May 13, 2021 @01:13PM (#27144621)
Here's an analysis of the CAPS system's safety record: https://www.youtube.com/watch?v=zT58pzY41wA (contains some good footage of an SR22 parachuting into the ocean, and into the ground).

This is a good overview on the survivability of water landings: https://www.youtube.com/watch?v=0LwGYBBhTss. I haven't watched the video recently but I think even a 172 that cartwheels after landing has a pretty good survivability rate, something like 90%. Parachute is a nice to have, of course.

Re:Midair Collision over Denver by tialaramex on Thursday May 13, 2021 @02:42PM (#27145688)
Paul Bertorelli is a lot of fun, I have seen those videos a while back. I enjoy his "cheap pilot bastard" attitude to things even if maybe I don't agree with it.
Re:Midair Collision over Denver by maweki on Thursday May 13, 2021 @06:20AM (#27140511)
That's exactly what I wondered about. How one parachute and two crew can lead everybody uninjured.
Re:Midair Collision over Denver by dmix on Thursday May 13, 2021 @05:22AM (#27140171)
> The device is attributed with saving over 200 lives to date.

https://www.cirruspilots.org/Safety/CAPS-Event-History

Re:Midair Collision over Denver by sokoloff on Thursday May 13, 2021 @06:48AM (#27140670)
That particular phrasing and calculation, suggesting that every chute deployment without fatalities represents that number of people “saved” is quite controversial and IMO not supported by an analysis of the data.

I think it’s great that the system exists, it has undoubtedly saved lives, but unless Cirrus crashes are overwhelmingly fatal compared to other airplanes, it’s overstating “fatal accidents turned into non-fatal accidents” by likely a factor of ~3 and number of fatalities avoided by ~4.

This type of mishap is probably the best scenario for a chute, though. I have no illusions that following a mid-air that I am still a strong favorite to bring my non-chute airplane to earth without fatalities. (The stats say I’m about a 60:40 favorite to do so.)

CAPS saves lives. CAPS has not saved the lives of every person who survived a CAPS deployment, because most of those would have survived anyway. In most off-airport arrival scenarios, I’d be wishing to have a chute.

* - One of my instructors was in command for CAPS Event #46

Re:Midair Collision over Denver by mannykannot on Thursday May 13, 2021 @07:58AM (#27141101)
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 injured. This will presumably further muddy the used/saved ratio, while probably increasing the total number of saved.

In a collision situation, at least one as violent as this one, you can't be sure whether some vital control or structure has been damaged to the point where it is about to fail, so using a parachute of any sort, where feasible, seems to be the rational choice.

Quite by accident, I came across this pucker-inducing article a couple of days ago, where thre's little doubt that bailing out, if it were an option, would have been the right thing to do, even though this flight ended safely in this case.

https://airfactsjournal.com/2019/03/student-flight-control-j...

(On second thoughts, if the pilot had a parachute, he could have attempted to free up the controls without making his situation any worse.)

Re:Midair Collision over Denver by elliekelly on Thursday May 13, 2021 @09:32AM (#27141861)
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.
Re:Midair Collision over Denver by sokoloff on Thursday May 13, 2021 @10:19AM (#27142361)
There are no emergency-specific fees. Whether Newark (I think it was EWR, not LGA) would assess a normal landing fee is probably not a consideration for the pilot, especially back then.

Landing fees are quite reasonable. Off peak, the landing fee would be $25 now. On peak, it would be $125.

https://www.panynj.gov/content/dam/airports/pdfs/scheduleofc...

Re:Midair Collision over Denver by elliekelly on Thursday May 13, 2021 @11:31AM (#27143252)
Wow that's surprisingly low! I was imagining the fee was thousands of dollars.
Re:Midair Collision over Denver by TylerE on Thursday May 13, 2021 @03:10PM (#27146059)
Where they'll get you (for normal operations) is things like parking fees. At Newark, for an aircraft less than 100,000lbs that is $45/8 hrs.
Re:Midair Collision over Denver by maigret on Thursday May 13, 2021 @11:50AM (#27143489)
It depends on your aircraft weight basically
Re:Midair Collision over Denver by mannykannot on Thursday May 13, 2021 @10:35AM (#27142522)
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 by mlyle on Thursday May 13, 2021 @02:43PM (#27145705)
> . I have no illusions that following a mid-air that I am still a strong favorite to bring my non-chute airplane to earth without fatalities. (The stats say I’m about a 60:40 favorite to do so.)

Note this was a midair with a much larger, faster aircraft and at an unfavorable aspect. The empennage was sliced nearly entirely through by the other aircraft's propeller and the elevator/horizontal stabilizer is deflected into a position commanding a steep dive.

Re:Midair Collision over Denver by akouri on Thursday May 13, 2021 @07:47AM (#27141018)
The SR-22 also cannot recover from a spin. I would assume most of those deployments are from out of control spins. I am not sure the parachute system can be credited for saving more lives than a similar plane not-equipped, because the Cirrus _needed_ that parachute system in order to be certified.
Re:Midair Collision over Denver by sokoloff on Thursday May 13, 2021 @07:54AM (#27141073)
> The SR-22 also cannot recover from a spin.

The SR-22 can recover from a spin, using conventional anti-spin control inputs. EASA testing showed that.

It is true that Cirrus secured an “equivalent level of safety” ruling during FAA certification and so did not demonstrate conforming spin recovery in flight testing here, but it can recover.

Re:Midair Collision over Denver by shadowgovt on Thursday May 13, 2021 @12:59PM (#27144468)
I remember when these were being tested. Some of the testing was done at the NASA Langley center, which still today specializes in airframes in addition to space... They have a whole-airframe catapult and drop system.

These parachutes have been an absolute game-changer for small aircraft pilot survival. It's unlikely this kind of collision would have been survivable for the small-plane pilot 25 years ago.

Re:Midair Collision over Denver by Aeolun on Thursday May 13, 2021 @07:41AM (#27140982)
Ah, that’s why I only read about one parachute for two passengers :D
Re:Midair Collision over Denver by jonplackett on Thursday May 13, 2021 @06:01AM (#27140407)
I don't know why this blew my mind so much, but it did.
Re:Midair Collision over Denver by alister on Thursday May 13, 2021 @07:30AM (#27140918)
What are the problems with making such a system for large passenger aircraft (perhaps with multiple parachutes)?
Re:Midair Collision over Denver by mikepurvis on Thursday May 13, 2021 @07:44AM (#27141002)
The sibling comments make some of the same arguments, but here’s an article which also addresses it:

"An aircraft is most vulnerable during take-off and landing because it is closer to the ground (its biggest obstacle), and is travelling at low speeds and therefore is harder to manoeuvre. According to statistics from Boeing, almost three-quarters of deaths from plane crashes between 2005 and 2014 occurred during these phases of flight. But this is the time when a detachable cabin would least likely be successful at saving lives. Being closer to the ground would give the pilot much less opportunity to jettison the cabin following an incident and if it were detached it could well land in a built-up area."

https://theconversation.com/why-a-detachable-cabin-probably-...

Re:Midair Collision over Denver by marcinzm on Thursday May 13, 2021 @07:59AM (#27141107)
To add to another comment larger planes have much better redundancy (multiple engines, multiple control lines, multiple pilots, etc.) so the situations where a parachute would help are much much fewer. So weight is probably better spent on making the redundant systems even more redundant than anything else.
Re:Midair Collision over Denver by gecko on Thursday May 13, 2021 @07:35AM (#27140951)
The drastically higher speeds involved (250-300 knots airspeed, as opposed to more like 50-90 knots for GA aircraft), combined with drastically higher weights (think about the chutes needed for something like Apollo, which is nowhere near the size of a large passenger aircraft, and realize you need way more) would both be major issues. There’s also the simple fact that larger passenger aircraft tend not to fail this way, making it less likely such a system would help even if it existed.
Re:Midair Collision over Denver by MauranKilom on Thursday May 13, 2021 @07:42AM (#27140988)
I would expect the problem to be "mass goes up with size cubed, while parachute drag only goes up with size squared". I.e. you need a disproportionately larger chute (or more of them) for large aircraft. Those are dead weight in normal operation, which really hurts the economics.
Re:Midair Collision over Denver by morcheeba on Thursday May 13, 2021 @10:55AM (#27142777)
I'll add on to the good points other have made here - smaller planes tend to fly out of small airports in the suburbs or the countryside. Larger planes fly out of much more urban areas, where there are a lot more obstacles, making a safe landing less probable.