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Midair Collision over Denver

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Re: Midair Collision over Denver

#111

Post by elliekelly »

azalemeth wrote: post #33
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…

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’ve probably mentioned this book on HN a hundred times but “Black Box Thinking” discusses the aviation culture of avoiding blame and making sure a problem isn’t repeated and how other industries (like medicine) would benefit hugely from a similar approach. It’s really interesting.

Re: Midair Collision over Denver

#112

Post by sokoloff »

travisjungroth wrote: post #108
sokoloff wrote: post #85

Earlier quoted context omitted.

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 you ever seen the optional 7th seat for a PA-32? It makes for 3-across in the back row which makes the backseat of a 911 look positively roomy.

Re: Midair Collision over Denver

#113

Post by kbutler »

qayxc wrote: post #81
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…

> 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…

6 * 1.18 = 7.08 people, so that could explain 1 adult.

I think the "some adults, some kids" is more significant - similar to back seats in many small cars - you can put 3 passengers in there, but 3 adults won't be happy.

Re: Midair Collision over Denver

#114

Post by londons_explore »

dkarras wrote: post #60

Video of the cirrus chuting down: https://twitter.com/DenverChannel/status/1392560583950561281 A photo of the airborne metroliner with fuselage blown open: https://imgur.com/gallery/yKPOWR0

The plane flying missing half the fuselage suggests to me that fuselage was excessively strong (and therefore heavy and expensive).

A tube is only strong when complete. Cut away half the tube and bending resistance probably goes down ~10x.

Re: Midair Collision over Denver

#115

Post by mistrial9 »

hirundo wrote: post #107
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…

thirty foot jump as a passenger in a 4-seater here at 10,000 feet in the mountains - I hear you! :D

Re: Midair Collision over Denver

#116

Post by sokoloff »

t0mas88 wrote: post #106
sokoloff wrote: post #63

Earlier quoted context omitted.

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…

NB: There is no instrument approach to 17R @ KAPA.

I agree I'd have an extended centerline up (it's up by default if I zoom the MFD in close enough in my lesser-equipped A36), but this is a fully visual maneuver.

Almost no one is going to define a user waypoint near the touchdown zone for 17R and pull an OBS line off that just so they can use the FD/AP to make an entirely routine turn to final.

Re: Midair Collision over Denver

#117

Post by cesarb »

londons_explore wrote: post #114
dkarras wrote: post #60

Video of the cirrus chuting down: https://twitter.com/DenverChannel/status/1392560583950561281 A photo of the airborne metroliner with fuselage blown open: https://imgur.com/gallery/yKPOWR0

The plane flying missing half the fuselage suggests to me that fuselage was excessively strong (and therefore heavy and expensive). A tube is only strong when complete. Cut away half the tube and bending resistance probably goes down ~10x.

> The plane flying missing half the fuselage suggests to me that fuselage was excessively strong (and therefore heavy and expensive).

It's probably the opposite: that the fuselage was only strong enough to resist the air pressure differential, and that the real structural component was the cabin floor. And that, luckily, the control cables for the tail were routed through the cabin floor, instead of through the top of the cabin.

Re: Midair Collision over Denver

#118

Post by phkahler »

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.

>> 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.

When you get your medical clearance, one of the things they look for is signs of psychological issues or instability. Not saying that's you, and I bet you'd do better than you think. Pilot training also IMHO makes you better at that stuff.

Re: Midair Collision over Denver

#119

Post by captainredbeard »

qayxc wrote: post #81
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…

> 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…

Wrong - most singles can’t fill the seats and the tanks. This is general aviation 101 folks

Re: Midair Collision over Denver

#120

Post by t0mas88 »

sokoloff wrote: post #116
t0mas88 wrote: post #106

Earlier quoted context omitted.

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…

NB: There is no instrument approach to 17R @ KAPA. I agree I'd have an extended centerline up (it's up by default if I zoom the MFD in close enough in my lesser-equipped A36), but this is a fully visual maneuver. Almost no one is going to define a user waypoint near the touchdown zone for 17R and pull an OBS line off that just so they can use the FD/AP to make an entirely routine turn to final.

That makes things a lot harder for the Cirrus pilot. Easy to get the lineup slightly wrong with for example some wind correction in from far away. Crazy that ATC had them do this at the same altitude as conflicting traffic with no underlying approach as a safety net. You can ask someone not to go through final, but that's very easy to miss judge from a couple of miles away.
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