from Hacker News

Midair Collision over Denver

by lunchbreak on 5/13/21, 5:10 AM with 231 comments

  • by nickcw on 5/13/21, 7:13 AM

    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.

  • by mdip on 5/13/21, 11:06 AM

    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 bad weather[1]. He was traveling with his daughter, a friend and, I think, his wife. He died, but his daughter was able to get free and make her way to a nearby farm to call for help. Looking at the plane, the fact that anyone survived at all let alone walked to a nearby house with minor injuries is pretty miraculous.

    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. I have no idea the kinds of structural technologies are involved in the aircraft but I know his plane was made in the 70s and was light enough that he only had a pole which attached to the front landing gear to pull it out of the hangar. The weight is so critical that the 7-seat plane can realistically only seat 4-5 adults. I remember being shocked that they had to weigh the paint they applied when he had the plane re-painted.

    [0] I'll spare the details as I have left many comments in the past about his experiences.

    [1] https://aviation-safety.net/wikibase/43894 - "Pilot Error"; I recall my Dad saying "all plane crashes are pilot error"

    [2] https://en.wikipedia.org/wiki/Piper_PA-32_Cherokee_Six

  • by dkarras on 5/13/21, 10:59 AM

    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

  • by _s on 5/13/21, 7:11 AM

    Private Pilot here - just thought I'd chime in quickly;

    Many aviation enthusiasts / pilots first go to is to have a look at the flight data - usually available on FlightAware / FlightRadar24 and a few other websites, plus LiveATC usually can provide recordings of the flights communications to towers as well. We should refrain from using just those data points to draw conclusions to the cause; the NTSB (and other orgs) will perform an investigation and the report will be made public (both interim, and final ones), and changes are almost always made to processes / systems, and often to the virtual or physical items that led to this incident.

    There are a few more photos and insights from various folks that were there at the time and captured a few moments on the reddit thread here:

    https://www.reddit.com/r/flying/comments/nauck8/mid_air_just...

    Note - it's incredibly rare for a midair not to result in fatalities so an incredible amount of luck all around.

  • by gresrun on 5/13/21, 7:07 AM

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

  • by bartread on 5/13/21, 9:30 AM

    Bloody hell: the state of that Metroliner. Surprised it held together with that amount of damage, and huge kudos to the pilots for getting it on the ground safely.

    For such a serious accident this seems about the best possible outcome for the crew of both aircraft. I'm not an expert so I'm not going to comment on root cause or blame here, but simply glad to read that at least everybody survived.

  • by franciscop on 5/13/21, 7:45 AM

    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.

  • by FatalLogic on 5/13/21, 7:52 AM

    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

  • by ChrisMarshallNY on 5/13/21, 11:12 AM

    Glad no one was injured or killed. Sounds like the Metroliner pilot did very well.

    I really think that we should not have flying cars until we have true autopilot (hands off the wheel, meatbag!). The thought of the "Hey y'all! Lookit this!" knuckleheads that regularly open up, roaring past my house, in three dimensions, is chilling. They are bad enough with just two.

    I'll bet that the advent of true driverless tech will also be the advent of illegal aftermarket "mod kits." I can see it now...the "Hold My Beer™" line of manual override modules...

  • by schoen on 5/13/21, 5:15 PM

    I remember seeing some Internet post a couple of decades ago where someone asserted that the goal of ATC was to prevent midair collisions and that U.S. ATC had met this goal perfectly, with no midair collisions between aircraft that were under the control of ATC at the time.

    I think the claim was qualified in some way like "collision between civilian flights that were both flying an ATC-assigned clearance at the time". (So some kinds of flights and some kinds of airspace don't require ATC clearance, and if one of them were involved in a collision, it wouldn't be ATC's responsibility, in some sense.)

    My question at the moment is: is this claim plausible if you qualify or restrict it enough? Do you have to tack on additional conditions?

    Is there any useful sense in which this collision was a first for U.S. aviation history?

  • by gkanai on 5/13/21, 9:00 AM

    Commercial pilot Juan Browne covers this on his channel:

    https://www.youtube.com/watch?v=_Ph7OR6C90w

  • by na85 on 5/13/21, 8:02 AM

    I was camping near Whistler a few years ago and heard a bang. Looked up and saw falling debris and bodies. A wing landed not far from our campsite. Turns out a glider (low-wing monoplane) was descending and the tow plane (high wing monoplane) was climbing. They were each in each other's blind spots :(

    Glad to see no fatalities here; I'm an aerospace engineer in the field of airworthiness and technical risk management so my work sees a lot of accident reports and flight safety incidents. I can say with certainty these folks (esp. the metroliner crew) are very fortunate.

  • by xattt on 5/13/21, 7:07 AM

    It’s amazing there were no casualties. The novelty of the report is the use of a rescue parachute by the Cirrus plane.

  • by FabHK on 5/13/21, 5:19 PM

    I wonder how many mid air collisions we would expect to see if see-and-avoid where entirely ineffectual, or pilots would not look outside ever except to land. I have the impression the accident numbers would not be much worse than they are.

    In other words, my hypothesis is that the fact that there are few mid-airs is owed to ATC, technology (TCAS, TAS) and “big sky”, rather than vigilant pilots.

  • by cmckn on 5/13/21, 9:23 AM

    I've spent a decent amount of time at Centennial; it's one of the busiest general aviation airports in the country. There's a great restaurant on site that you can watch the runways from. After this incident, the restaurant is probably as close as I'd get to a Cirrus. :)

  • by vertis on 5/13/21, 11:55 AM

    This[0] youtube video has good explanation with the air traffic control audio. The metroliner pilot was cool as a cucumber after being hit.

    [0]: https://www.youtube.com/watch?v=_Ph7OR6C90w

  • by HHalvi on 5/13/21, 1:31 PM

    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

  • by MobileVet on 5/13/21, 2:49 PM

    Wow, the 'can opener' effect is intense. Insane that the plane held together, so much structural loss.

    Reminds me of the Aloha Flight 243. My mom's cousin was the pilot and hearing his first hand account was pretty crazy. Fun fact, he got to be an extra in the made for TV movie of the event.

    https://www.thisdayinaviation.com/tag/robert-l-schornstheime...

  • by ardit33 on 5/13/21, 7:12 AM

    Spoiler: No one died, so it has a happy ending

  • by onion2k on 5/13/21, 7:34 AM

    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.

  • by martyvis on 5/13/21, 11:55 AM

    As always, Juan Browne has great reporting and analysis of this incident https://youtu.be/_Ph7OR6C90w

  • by 0xFFFE on 5/13/21, 8:06 AM

    Comms between tower and the planes involved. https://www.youtube.com/watch?v=f5tb2dVWJqc

  • by wiedehopf on 5/13/21, 2:10 PM

    Exact tracks of both aircraft with timestamps: press K to enable labels https://globe.adsbexchange.com/?icao=a4eabe,a2cee7&lat=39.63...

  • by shockeychap on 5/13/21, 2:46 PM

    The picture of the Metroliner reminds me of the Aloha Airlines incident.

    https://en.wikipedia.org/wiki/Aloha_Airlines_Flight_243

    It's amazing that the hull can survive in the air for any time with that much torn away.

  • by EricE on 5/13/21, 4:27 PM

    Juan Browne of the blancolirio YouTube channel did his usual excellent overview: https://www.youtube.com/watch?v=_Ph7OR6C90w

  • by nitrogen on 5/13/21, 7:12 AM

    No injuries reported. Kind of fascinating to read.

  • by zed88 on 5/13/21, 8:45 AM

    Metroliner, often jokingly called as "flying sewer pipe" is one hell of a sturdy plane it seems. Glad to see both parties okay, but this makes me think if BRS should be made standard by FAA on GA planes given the lives saved by the technology so far.

  • by throwawaygimp on 5/13/21, 7:59 AM

    @dang "Mid air just north of KAPA- all parties OK" is the more appropriate headline on reddit.

    As an aviator my stress levels are only just coming down now from seeing this headline and clicking expecting there to be deaths.