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Midair Collision over Denver

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11–20 of 237 posts

Re: Midair Collision over Denver

#11
post #9

I find it slightly incredible that two planes ever hit each other given the size of planes compared to the volume of space they fly in. I understand that it's simple probability (small planes, big volume, but lots of flights) but it's still amazing that it happens at all.

Less incredible in this case since it was two planes landing on parallel runways at the same time.

Re: Midair Collision over Denver

#12
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…

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

#13
No deaths nor injuries involved, which I feel like this should be in the headline. I came in expecting to see at least a commercial flight was involved (how does it make to #1 on HN otherwise?) but was very relieved to see it was two small aircrafts with 1 and 2 pilots respectively and everyone survived safely.

Re: Midair Collision over Denver

#14
post #9

I find it slightly incredible that two planes ever hit each other given the size of planes compared to the volume of space they fly in. I understand that it's simple probability (small planes, big volume, but lots of flights) but it's still amazing that it happens at all.

The probability is much higher in terminal airspace because all planes are going to or coming from the airport so they are on converging paths by definition.

And better GNSS based navigation equipment is now making it more likely than 20 years ago. The historical accuracy was such that planes where often a bit offset left or right off the route giving extra separation. Now the accuracy is so good that planes going opposite direction on the same route are passing exactly bang in the middle on top/below each other.

Re: Midair Collision over Denver

#15
It's strange that the planes were supposed to be flying parallel and yet the damage to both planes in the photos suggests a collision at right angles

Remarkable that the Metroliner held together, despite that terrible damage, and they landed it safely

edit: interesting photo of the landing from the Reddit thread linked elsewhere https://imgur.com/gallery/yKPOWR0

Re: Midair Collision over Denver

#16

No deaths nor injuries involved, which I feel like this should be in the headline. I came in expecting to see at least a commercial flight was involved (how does it make to #1 on HN otherwise?) but was very relieved to see it was two small aircrafts with 1 and 2 pilots respectively and everyone survived safely.

> I came in expecting to see at least a commercial flight was involved (how does it make to #1 on HN otherwise?)

The Metroliner (one with the fuselage ripped through) is commercial, [0] but apparently carrying cargo only in this case. [1]

Surely a mid-air collision even between two hobby Cessnas say is rare/interesting enough to make it?

[0] - https://www.keylimeair.com/

[1] - https://www.aopa.org/news-and-media/all-news/2021/may/12/col...

Re: Midair Collision over Denver

#17
post #14
post #9

I find it slightly incredible that two planes ever hit each other given the size of planes compared to the volume of space they fly in. I understand that it's simple probability (small planes, big volume, but lots of flights) but it's still amazing that it happens at all.

The probability is much higher in terminal airspace because all planes are going to or coming from the airport so they are on converging paths by definition. And better GNSS based navigation equipment is now making it more likely than 20 years ago. The historical accuracy was such that planes where often a bit offset left or right off the route giving extra separation. Now the accuracy is so good that planes going op…

Yea, this is a really good point that isn't well known.

We've improved GNSS significantly, but the technology to avoid collisions hasn't been widely deployed, even though it's orders of magnitude less complicated than high accuracy GNSS on the whole

So... a random dilution of precision generator could... save lives? ha.

Re: Midair Collision over Denver

#18

No deaths nor injuries involved, which I feel like this should be in the headline. I came in expecting to see at least a commercial flight was involved (how does it make to #1 on HN otherwise?) but was very relieved to see it was two small aircrafts with 1 and 2 pilots respectively and everyone survived safely.

The Metroliner isn't really a small (private) aircraft, it's more a commuter type aircraft, 19 seats. But in this case it was only carrying cargo so the place of impact didn't have any people in it.

Another lucky point is that it was at low altitude and at slow speed (preparing to land). Higher up it would have been much more likely to break up due to way higher speed and larger pressure difference between the cabin and outside.

Re: Midair Collision over Denver

#20
post #8
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…

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.

My less charitable reading was that the pilot abandoned the Cirrus on a parachute, but then it seemed like the plane landed…
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