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Midair Collision over Denver

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Re: Midair Collision over Denver

#101

Post by osenthuortuh »

sillysaurusx wrote: post #93
mdip wrote: post #62

Wow, that's incredible. Goes to show that people do walk away from plane crashes with some regularity. My father was a pilot[0]. He sold his plane about 15 years ago (to a group of owners, one of which was a priest, I'm sure there's a joke in there). A few of winters later, he was called out to Romeo Airport; the pilot flying the plane that was formerly his had crashed the aircraft a few miles short of the runway in…

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.

Re: Midair Collision over Denver

#102

Post by t0mas88 »

papercrane wrote: post #90
t0mas88 wrote: post #30

Earlier quoted context omitted.

The ICAO airport code as used for navigation. They're different from the IATA 3 letter codes that most passengers know. US airports start with K, European with E (e.g. EF for Europe-France). Often for large airports the code is very similar to the IATA code for passengers, e.g. KJFK for JFK and KSFO for San Francisco. But not always, as in EGLL for London Heathrow which is LHR in passenger codes.

> European with E (e.g. EF for Europe-France). EF is Finland actually. The first letter is region code, and Europe is divided into multiple regions. Northern Europe is E, Southern Europe is mostly L (so France is LF). Wikipedia has a nice map showing the different boundarys on it's ICAO airport codes page. https://en.wikipedia.org/wiki/ICAO_airport_code#/media/File:...

Haha sorry, you're right bad example.

Re: Midair Collision over Denver

#103

Post by HHalvi »

I felt erilly familiar with the details of this accident after reading the details. I dug up my browsing history and realized I watched the ATC exchange of this very collision yesterday not realizing that this had happened the very same day the video was uploaded[0]. Also props to the Cirrus Airframe Parachute System (CAPS), hope this gets implemented in more smaller (or homemade) aircrafts.

[0] https://www.youtube.com/watch?v=f5tb2dVWJqc

Re: Midair Collision over Denver

#104

Post by elliekelly »

mannykannot wrote: post #76
sokoloff wrote: post #58

Earlier quoted context omitted.

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-f…

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.

Re: Midair Collision over Denver

#105

Post by throw0101a »

elliekelly wrote: post #99
tialaramex wrote: post #36

Earlier quoted context omitted.

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 i…

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?

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

#106

Post by t0mas88 »

sokoloff wrote: post #63
t0mas88 wrote: post #25

Earlier quoted context omitted.

The Cirrus overshot the centerline of the runway it was supposed to land on. The common way for these situations is for the plane to be on an intercept angle towards the centerline. That's a max 30 degree angle for an instrument approach, but this was a visual approach so it could have been a sharper angle. All it takes to make this mistake in a Cirrus (and other G1000 avionics type small airplanes) is to forget 1 bu…

If the 1 button on autopilot mode is the red autopilot disconnect, “time to hand-fly” button, I agree with you. This turn to final (with the unusual additional warning to “do not fly through final”) is a visual maneuver and I’d expect most every pilot to be hand-flying at that point. (My autopilot and navigator is capable to make that intercept, but it’s way more tedious and distracting to program it than to just fly…

In the airline world it would at the very least be encouraged and in many cases mandatory to have the underlying approach programmed for this anyway. Even more so if told not to fly through final you would have the localizer up and monitor it.

In a Cirrus with what is probably a GFC 700 with flight director capabilities I would expect any competent instrument rated pilot to have the FD on and approach mode armed (the 1 missing button I meant) exactly to avoid this mistake.

Great to hand fly, but in a capable airplane just plain stupid not to use all the tools. And even mandatory on the professional side of things in many cases.

Re: Midair Collision over Denver

#107

Post by hirundo »

mdip wrote: post #62

Wow, that's incredible. Goes to show that people do walk away from plane crashes with some regularity. My father was a pilot[0]. He sold his plane about 15 years ago (to a group of owners, one of which was a priest, I'm sure there's a joke in there). A few of winters later, he was called out to Romeo Airport; the pilot flying the plane that was formerly his had crashed the aircraft a few miles short of the runway in…

> It's hard to impress upon folks who have never been in a small plane like that just how ... yeah ... how much it feels like you're hanging onto a kite.

Years ago I was doing pilot training in a Cessna 152. A coworker of mine was a retired Navy captain and instructor at the TOPGUN program, with hundreds of carrier landings in an F-14. He looked at me like I was crazy. He said those little planes were deathtraps and he'd never go up in one again.

Not long after that I had a lesson that coincided with some turbulence from the nearby coast. The plane janked around by seemingly hundreds of feet in every direction. I was scared (almost literally) shitless, and that was my last lesson. I haven't been in a small plane since.

Re: Midair Collision over Denver

#108

Post by travisjungroth »

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…

The point of the person you're replying to is that people have gotten bigger, which is a fact. Pointing out the comfort of levels of people in airplanes today doesn't dispute that.

It used to be more common to have a flexible combination of seats/baggage/fuel. But pilots flip out (or crash) if they can't fill the tanks, every seat and the baggage compartment and come in under gross. So the same airplanes often don't have the "bonus seats" they used to.

Numbers from Wikipedia, from the 1972 PA-32 owners handbook:

3,400 lb gross - 1,788 empty - (4 hours * 15gph * 6 lbs) / 7 passengers = 178 lbs per passenger. The average adult in the 70s was about 160. So you're not going across the country, but you could safely do a day trip with a 90 minute flight each way.

Now the average adult is 180. And they're a little taller than they were in the 70s, but not much. So every passenger has an extra 20 pounds horizontally. So in 2021, you'd be just over gross except that the people can't actually fit in the airplane.

Re: Midair Collision over Denver

#109

Post by londons_explore »

JohnJamesRambo wrote: post #88
nickcw wrote: post #7

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 becom…

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…

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

#110

Post by [deleted] »

ordu wrote: post #28
gresrun wrote: post #2

ATC comms with visualization: https://www.youtube.com/watch?v=f5tb2dVWJqc

The pilot is speaking about failed engine after the collision, like it is nothing. Fascinating. I'd be shouting something obscene in such a situation. For half an hour at least, I think.

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