Twin engine plane into hangar in Addison, Texas, at least 10 dead
 

N534FF.

https://flightaware.com/live/flight/N534FF

https://www.flightradar24.com/data/aircraft/n534ff

http://archive-server.liveatc.net/ka...2019-1400Z.mp3

AviationDB - Aviation Database - Aircraft N534FF

Sad news, but you would think that CBS would know the difference between a hanger and a hangar!

A rough nine days for turbo-twins... :(

Just by reading the initial witness reports in that article, it sounds like it could be similar to the King Air crash in Australia https://www.pprune.org/pacific-general-aviation-questions/591237-king-air-down-essendon.html?highlight=essendon

That was my first thought too ... time will tell.

Curb your expectations - this is CBS after all...

Cut n paste ?
https://www.bbc.co.uk/news/world-us-canada-48821328

Texas plane crash: 10 killed after "aircraft veers into hangar

N534FF is a previous identity for the aircraft in question, which was re-registered N511EF in April though some of the flight-trackers don't seem to have caught up yet.

https://registry.faa.gov/aircraftinq...mbertxt=N511EF

I think this is the first fatal accident of a King Air 350.
They are truly fine aeroplanes so it will be interesting to see what happened.

First in the USA.

There have been fatal B350 accidents in Germany (2006), Brazil (2009) and Chile (2012).

The folks flying the plane hadn't caught up either in the LiveATC link above. "Tower, 534 Fox Fox ready to go runway 15."

Video of the Sunday night NTSB media update, the uncertainty on the tail number is mentioned since the aircraft "recently changed hands".

https://www.nbcdfw.com/news/local/Ra...512040712.html

NTSB July 1st Update: Part 91 Operation
 

NTSB Monday July 1st Presser: https://www.youtube.com/watch?v=Aet2JEyvAoQ

NTSB B-Roll Video: https://www.youtube.com/watch?v=iQxnzK7WWEo

FAA Part 91 Operation forms part of the investigation. CVR being analysed in Washington DC.

(Audience member witness suggested that the flight profile resembled a stall-spin.)

I'd be surprised if that F900 ever flies again.

Three pictures released today by the NTSB (but the picture with a view inside the hangar is not the one displayed at the briefing).


https://cimg9.ibsrv.net/gimg/pprune....e760e49a86.jpg
https://cimg0.ibsrv.net/gimg/pprune....7721624ae6.jpg
https://cimg8.ibsrv.net/gimg/pprune....e1117ce370.jpg

How about the one at Wichita, crashed into the simulator building?

King Air vs PC-12
 

People I worked for purchased a King Air 200 3 years back and love it. They were adamant on a twin for safety when I suggested a PC-12. I did not get into the whole single versus twin things with them. They own the company and have managed quite well without my advice.
Assuming we are dealing with an engine failure here a single would have been "safer". Half the chance of having the failure in the first place. If you do have one at takeoff, a much better chance of a controlled return to earth. Land straight ahead and fly the plane and you very likely walk away.
The Wichita crash mentioned above, if it is the one I read about, involved a highly regarded instructor. I think that plane was just out of maintenance. Clearly EFATO is a very demanding and dangerous situation.
Sad day for all involved. I enjoy flying private but it is not without its risks.

Is the King Air 350 Perf A or B?

Today's NTSB briefing:


Excerpts from a Dallas Morning News summary of the NTSB briefing:

Quote:

---

A cockpit recording from the plane that crashed Sunday at Addison Airport, killing all 10 people aboard, captures the moments when the crew recognized a problem with the left engine, officials said Tuesday.

The audio reveals a mood "consistent with confusion" just after the Beechcraft Super King Air 350 took off and about 12 seconds before the recording ends, said Bruce Landsberg, vice chairman of the National Transportation Safety Board.

NTSB officials said a preliminary examination of the cockpit voice recording yielded two hours of high-quality audio, giving investigators a glimpse into the terrifying moments before the aircraft hit the hangar and burst into flames.

The two crew members received three alerts warning they were in danger of hitting the ground three seconds before the recording broke off abruptly, presumably when the plane crashed into a hangar.

---

https://www.dallasnews.com/news/addi...on-plane-crash

A couple of CVR pictures from the NTSB lab in Washington, DC.


https://cimg5.ibsrv.net/gimg/pprune....ae70592a05.jpg
https://cimg6.ibsrv.net/gimg/pprune....51a502ba32.jpg

Licenses and medicals for the pilots.

The captain:


https://cimg1.ibsrv.net/gimg/pprune....10384bfd88.jpg

The first officer:


https://cimg7.ibsrv.net/gimg/pprune....97d850deeb.jpg

Hard to watch.
https://www.wfaa.com/article/news/lo...QyOOW7ZKU1yoQo

What I get is: "You don't have permission to access "http://www.wfaa.com/article/news"

Me too. Its data protection problem, since we are in the EU. Should be solved for you then, sooner or later ? :}

If you google the basics you will find videos from news stations.

A lot of U.S. websites can't justify the cost of complying with those wacky EU GDPR requirements for a few offshore viewers.

Here's a YouTube link to the video that might work overseas:

https://www.youtube.com/watch?v=Y3de...ature=youtu.be

Indeed an ungodly excruciating video to watch. A grim reminder of how quickly things can go from all is well to everything's going to hell.

That video footage certainly has the hallmarks of a Vmca incident, with such a sudden flip, if so then it's nothing like the Essendon incident referred to above.

It might be the camera angle / distortion but from the dash cam near the hangar, just before it snaps inverted it appears to be flying well out of balance....crabbing well sideways.

Very sad.

Yes, it appeared to be in a hard left hand skidding turn, and actually appeared to be flying almost sideways. It ultimately snap rolled to the left, going almost inverted prior to impact. As compressor stall pointed out above it could certainly be related to a Vmca (Vmc in U.S.) loss of control incident, and as far as my limited knowledge extends on this, the only way out at low altitude is to reduce the power on the good engine. That of course, requires nerves of steel.

I seem to remember a video from 3 or 4 years ago of some guys showing off in a King Air, I believe in Central or South America. Anyway, they were doing low level skidding turns near the airport and the video caught the exact same sort of abrupt violent snap roll as shown in the video of the Addison, Texas accident.

Having watched that alarming video, I am reminded of a special condition applicable to the 200's, 300's and 1900's which I encountered while conducting flight testing for a survey mod on a B200. (note that I have never flown a 300, though the special condition and TCDS state that it applies to the 300 also.

The special condition #23-47-CE-5, dated: October 15, 1973 includes the following letter from the FAA:

"Oct 15, 1973

ACE-216

Beech Model 200 angle of skid; Beech Aircraft Corporation
letter 908-189 dated August 23, 1973

Mr. C. A. Rembleake, Manager
Aircraft Production Engineering Division
Beech Aircraft Corporation
P. O. Box 85
Wichita, Kansas 67201

Beech has requested certification guidance for their model 200 relative to the term "appropriate to type" in FAR 23.177(a)(1). A joint Beech-FAA flight test was made August 17, 1973 to establish a basis for this guidance.

A qualitative investigation of the lateral-directional static stability shows the characteristics to be conventional. Skid angles of 20-25 degrees are obtained at 1.3Vs1 speeds and higher. For skid angles of 20-25 degrees, the rudder force and position stability gradients indicate positive stability at 1.2Vs1 speeds and higher.The destabilizing effects of the nose landing gear, the forward mounted nacelles, MC thrust and extreme aft C of G location, however, combine at 1.2Vs to permit skid angles in the 35-38 degrees range. The following observations are noted:

1. These large skid angles can be obtained with any flap deflection, but only in a narrow range of airspeeds of around 1.2Vs1. The skid angles reduce to the 20-25 degree range without pilot input if the airspeed varies as much as +5 knots with full rudder control.

2. The thrust dependence of the 35-40 degree skid angle is shown by immediate angle reduction (without overshoot) when the critical engine is suddenly failed.

3. Essentially, full up elevator is required to hold the airspeed at 1.2Vs1 in the maximum skid. If this deflection input is not precisely timed, the maximum skid will not develop.

4. Rudder position stability remains positive throughout the full rudder deflection range. Rudder force stability is positive at all points as rudder deflection is increased. Plots provided by Beech show that rudder force stability can be very weak as right rudder deflection is reduced through the 16 -21 degree range during airplane skids between 16 and 22 degrees. In practice, this was seen only as a showing of rudder free recoveries initiated at or above these combined values.

In assessing compliance with FAR 23.177, it is recognized that skid angles greater than +-20 degrees can be obtained. These are seen only in one carefully controlled test condition, and under such circumstances that are not likely to be duplicated in service without prior knowledge of both the characteristic, and the entry technique. Recovery by standard control inputs is prompt and straightforward, and there is no unsafe feature associated with either the extreme skid angles or the recovery.

Despite this, the +-20 degree skid angle is more correctly representative of the airplane's response to the flight conditions throughout its flight envelope. You may therefore consider a maximum skid angle of +-20 degrees as "appropriate to type" for the model 200 in interpreting FAR 23.177(a)(1) and amended by 23-1 through 23-9.

William J. Thievon, Chief
Engineering and Manufacturing Branch"

I did testing for this characteristic in a B200 with a long tailboom installed, and found it exactly as described. The airplane was controllable exactly as described, and recovered promptly if controlled to reduce the yaw angle. But is sure was weird flying somewhat sideways, while level, and at such a slow speed. What I did during that testing seemed very similar to me as what I see in that video, other than my entering with great caution and at altitude. I was flying a B200, though the TCDS applies this special condition to the 300 and 1900 as well (and this is hand written onto the typed special condition document from the FAA). I did not let the plane stall during this testing, and thus did not spin. But it sure seems that a spin would be very close at hand, and very rapid, if while flying in this condition, things were allowed to worsen. I imagine something like that which I see in the video. As the FA letter says, you're not supposed to be there, but I guess if you get there in error, and beyond, it can get bad fast.

It looks like the auto-feather is not initiated in the video as there appears to be more than windmilling on the left engine. I lost an engine on a 1900C just after rotation and the autofeather made it virtually a non-event. I was light compared to this aircraft which must have been near gross with 10 on and fuel for Florida. It takes a ton of leg to keep it flying without auto-feather.

The landing gear was still down. That's not helping if they lost power on one engine.

think they were in brain overload trying to regain control, which appears to have been lost shortly after liftoff...

Autofeather?
 

Maybe the autofeather was inop? Hard to believe because on every PT 6 I've flown that was a no-go item.

Possibly, but a mishandled EO situation can still get like that, even with it inop. It's not as if AutoFx is the magic fix for asymmetric flight. All it achieves is keeping the rudder input required below the certificated 150lb limit, and some short term performance gains as a by product.