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Midair Collision over Denver

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Re: Midair Collision over Denver

#221

Post by sokoloff »

captainredbeard wrote: post #119
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…

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

If you can fill the seats and the tanks (and be legal), I'd say someone made your tanks too small.

Re: Midair Collision over Denver

#222

Post by officeplant »

throwaway0a5e wrote: post #137
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 remember being shocked that they had to weigh the paint they applied when he had the plane re-painted. I used to work in general aviation. If my eyes could fly a loop in my skull they would have. Were the occupants required to use the bathroom before flying? That's how much weight you're potentially saving by weighing the pain…

>The specifications to which general aviation stuff is done isn't really any more exacting than stuff in automotive or heavy industry. The service literature is just more verbose and the service procedures are more tightly defined.

This reminds me of how often I quote weight limits on cars to people and their eyes go wide at how easy it is to exceed the OEM's recommended limits. I'm fairly sure I'm one of the few among my friend groups that has read through every owners manual for the cars/vans I've owned.

Re: Midair Collision over Denver

#223

Post by omegant »

mannykannot wrote: post #128
omegant wrote: post #40

Earlier quoted context omitted.

Looking at the youtube video of the radar with the radio sound that someone posted below, the Cirrus is cleared to runway 17R but he turns to runway 17L. There are 3 possibilities : 1- he mistakes one runway for the other visually, 2- he wrongly thinks he is cleared for the 17L runway 3- or he makes a too wide turn going for the 17R, intruding the 17L area. The cirrus is the one that makes the mistake. The 17 runways…

> I understand that they were in different frequencies with different controllers. If that is so, then it seems from the recording that the Metroliner pilot was only informed about the Cessna ahead of him and on approach to 17R, not of the Cirrus. The Cirrus pilot is told about the Metroliner in an exchange that goes thus: TWR: "Cirrus 6DJ, traffic you're following just turned right base there ahead and to your right…

“ Putting this together, I suspect the Cirrus pilot never registered the presence of the Metroliner until the collision - and I doubt the Metroliner pilot saw the Cirrus even after the collision, given that he thought he had an engine failure”

This is what I think aswell. The overshoot may be either way a miss identification of the runway, or just a poorly executed turn to final of the 17R. The investigation is going to be interesting.

Re: Midair Collision over Denver

#224

Post by lujim »

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

Wow the Cirrus is looking pretty good for how much damage it did to the Metro. Flight surfaces are still there and it's only broken in half of the parachute landing. Guessing it might not have been controllable after the collision.

Re: Midair Collision over Denver

#225

Post by sokoloff »

mannykannot wrote: post #128
omegant wrote: post #40

Earlier quoted context omitted.

Looking at the youtube video of the radar with the radio sound that someone posted below, the Cirrus is cleared to runway 17R but he turns to runway 17L. There are 3 possibilities : 1- he mistakes one runway for the other visually, 2- he wrongly thinks he is cleared for the 17L runway 3- or he makes a too wide turn going for the 17R, intruding the 17L area. The cirrus is the one that makes the mistake. The 17 runways…

> I understand that they were in different frequencies with different controllers. If that is so, then it seems from the recording that the Metroliner pilot was only informed about the Cessna ahead of him and on approach to 17R, not of the Cirrus. The Cirrus pilot is told about the Metroliner in an exchange that goes thus: TWR: "Cirrus 6DJ, traffic you're following just turned right base there ahead and to your right…

160 kts (around 140 indicated) does not seem like a remotely appropriate airspeed to join a pattern full of Cessnas in closed traffic.

SR22 Vs0 is 59 knots (call it 60 to make the math easier). 1.3 x Vs0 is a reasonable "over the fence" speed, so 78 knots (call it 80) indicated would be good on short final, maybe 90 on base-to-final. (Instead, they were descending and thus accelerating slightly and hit 169 knots on the base leg.)

Bombing into the pattern over 50 knots faster than appropriate (70 knots faster than the traffic you're following and 40 knots faster than the much larger and on-profile Metro on the parallel) might be contributing, but certainly suggests to me that the Cirrus crew was behind the airplane.

https://globe.adsbexchange.com/?icao=a4eabe,a2cee7,a90ffa&la...

Re: Midair Collision over Denver

#226

Post by NovemberWhiskey »

t0mas88 wrote: post #30
Grustaf wrote: post #22

Earlier quoted context omitted.

What is KAPA and do people know what it means?

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.

>US airports start with K

ICAO-registered U.S. airports in the contiguous 48 states start with a K. Alaskan and Hawaiian airports start with a P and other U.S. territories get other different initial letters depending on their region (e.g. TJ for Puerto Rico or NS for American Samoa).

Re: Midair Collision over Denver

#227

Post by ZeljkoS »

BashiBazouk wrote: post #176
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…

I once witnessed an airplane crash that everyone survived. I was a preteen hanging around outside the Scotts Valley roller rink with a friend in the early eighties. The roller rink is next to the now defunct airfield. The airfield was lower than the rink by an embankment. We had recently been watching Jaws on Betamax and my most persistent memory is seeing only the tail crossing the field. It reminded me of a shark f…

https://www.cultofmac.com/465778/today-in-apple-history-stev...

Re: Midair Collision over Denver

#228

Post by sokoloff »

agloeregrets wrote: post #219
MaxBarraclough wrote: post #138

Earlier quoted context omitted.

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…

I mean, would you rather the plane crash at 30mph at a chosen point or at 200mph wherever it leads?

Once you’re under chute, the airplane is picking the arrival spot.

Re: Midair Collision over Denver

#229

Post by DarmokJalad1701 »

throw0101a wrote: post #105
elliekelly wrote: post #99

Earlier quoted context omitted.

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 th…

> 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

#230

Post by quickthrower2 »

Grustaf wrote: post #22
throwawaygimp wrote: post #19

@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.

What is KAPA and do people know what it means?

Tbf it wouldn’t be the first abbreviation / jargon in a HN title
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