Blackhawk Crash Alabama
 

Just heard a Blackhawk has crashed in Huntsville Alabama, anyone have more information?

just found this

No survivors in fatal Madison County Black Hawk helicopter crash, officials say

• Updated: Feb. 15, 2023, 5:22 p.m.|
• Published: Feb. 15, 2023, 3:48 p.m.

https://www.al.com/pf/resources/imag...ook.svg?d=1003
https://www.al.com/pf/resources/imag...ter.svg?d=1003

NEW!

By

• Howard Koplowitz | [email protected]

Authorities responded to a helicopter crash Wednesday afternoon in Madison County that killed all people on board, officials said.

Authorities were dispatched to Burwell Road and Highway 53 at 3:01 Wednesday on a report of a crashed helicopter, said Don Webster with Huntsville Emergency Medical Services, Inc.

The helicopter was burnt.

Tennessee National Guard as reported by NBC news

Video below purportedly showing crash.
Appears to be an extremely high rate of descent - what could have caused that?!

practice SWP with harsh aft cyclic input

I hope the Flight Data Recorder survived, if there was a component failure leading up to this incident it would be good to know.

Lima models have had main rotor blades shed skin a handful of times and the aircraft landed safely. Maybe not this time. Tragic.

60mech

Now that Sir Korsky has solved the cause of this tragedy we can move on to other matters.

Care to explain how divined that information so quickly and with such certainty?

To me his post comes off less as asserting a cause rather than just a response to the question “what could cause such a high rate of descent”

That video is also shown as part of this article:

https://www.dailymail.co.uk/news/art...survivors.html

In this case it is an overall (rather than cropped) view from what looks to be a home security system running. But doesn't the audio in both cases sound very unrealistic, as if dubbed in afterwards? The video looks credible in which case the helicopter was in serious trouble from a substantial height.

It appears from that video that the aircraft came out of cloud inverted.

Edit:

Or, at least going inverted shortly after.

I flew Blackhawks for a few years and I can think of one failure that would cause the aircraft to pitch nose down. If the (normally automatic and active) tail stabilator motors fully down in the cruise (it should be up by around 40kts IAS if my memory is correct but it was almost twenty five years ago) it needs to be promptly dealt with by selecting it to manual and motoring it up to a neutral position.

If instead the stab is left down and the cyclic is moved an long way aft, in an attempt to correct the nose down attitude, it may be possible for the MRBs to contact the rear of the airframe.

What happened to the aircraft below had happened at least 3 times previously, but after thinking about it I don’t know that a worse failure(losing more surface area of the blade) would be the cause of this most recent incident. It seems like this would most likely result in the aircraft breaking up in flight.

I think responding to a stabilator failing out of auto mode improperly as others have suggested could have caused something like this. New York national guard had a crash caused during a checkride where the instructor pilot manually slewed the stabilator down in cruise flight while simultaneously silencing the master caution(at night under NVGs as well) The pilot on the controls didn’t have time to react to the failure.

There was also an accident in Maryland a few years ago where the entire tail rotor gearbox separated from the aircraft due to vibration from a failed tail rotor blade. The emergency procedure that came out of that one is optimistic to say the least.

https://cimg5.ibsrv.net/gimg/pprune....13d270d05.jpeg

Most accidents seem to come down to human factors, lessons can be learned and applied and I still feel
confident in the aircraft as a platform. Honestly, this one is getting to me because at this (very early) point it just looks like the aircraft killed them.

60mech

One thing to remember when viewing the video of the aircraft is the distance from the camera to the aircraft and the delay that causes between what you see and what you are hearing.

Consider the time lapse between when the aircraft disappears behind the tree and the time you hear the sound of the impact to get an idea of how much lag there is caused by that distance.

As to the NY Crash.....the IP did a very stupid thing and earns the responsibility for that crash and the aircraft should be seen as a victim.

Early on in this investigation there shall be some indication of whether the Rotor Head departed the aircraft or not and depending upon the location of the parts discovered will tend to point to where in the sequence of events that occurred if at all.

The Black Hawk is a proven aircraft and has been tested thoroughly from initial prototype stage right along to today.

As to the aircraft was thought to appear from out of the clouds then ATC should have recordings of any Radio Transmissions to/from the Aircraft as they would have in all likelihood been on an IFR Flight Plan or operating on an IFR Clearance of some kind.

The prevailing weather did not seem to be of the kind that would offer a risk of IIMC.

SASless,

I looked back at weather conditions at the time of the accident, overcast 1300 feet. We were talking in the office about possible spatial disorientation leading to a loss of control, but seems a stretch. It just seems like something had to have broken to get to this condition.

it’s a very populated area so if parts were coming off maybe something will be recovered.

I also have questions re how the video squares with a Stabilator failure, assuming it went full down in cruise flight for example, and how the aircraft would react.

My thought is the video shows a nose down pitch attitude but with the high rate of descent in that nose down attitude it seems to me the nose would have tucked more with the increasing airspeed and gone inverted.

Not saying that is my choice of causes....just trying to look at the video and question what we are seeing as we try to come up with possible causes.

What model UH-60 was it?

What kind of SAS/AP/FD gear did it have if any?

What was the nature of the training being conducted?

Were these Full Time Guard Pilots or Part Timers?

The formal investigation will offer up a great deal of information when it is all said and done.

SASless,

Great questions, here’s the current EP from the checklist:
https://cimg6.ibsrv.net/gimg/pprune....a3ab74d9d.jpeg
Now, I haven’t personally experienced a stab failure where the stab slewed down in cruise flight, it’s either failed to slew(program) up on takeoff(stayed -40degrees) resulting in the nose dropping, or one time it slewed full up (+10degrees)and stayed full up on takeoff resulting in a nose high attitude.

Pilots I work with who have experienced a stab programming down at higher speed combined with reduced collective have indicated it is a sobering experience and the speed at which the nose tucks is quite rapid.

Another accident in Egypt was caused by a stab that was repeatedly failing out of auto mode but they kept flying, manually controlling the stab. Then they did an airspeed over altitude takeoff from a cliff side LZ, where people liked to “dive” over the side of the cliff, the stab was still failed full down, resulting in a crash into said cliff face.

I certainly hope that nobody was messing with manual control STAB switch, there have been too many accidents due to that sort of thing.

In the video of the daily mail it appears to change instantly from not seeing it at all to seeing it very clearly. So it clearly appears that it flew in rather dense clouds and thus IMC when LoC occured. If that was IIMC and if this happened due to spacial disorientation or if the cause for the LoC was a mechanical malfunction obviously only the detailed investigation will be able to tell.

Experienced UH-60A Stabilaor Failure in cruise flight Circa 1985
 

On a return flight from Hartford, Ct to the Sikorsky Plant we experienced a stabilator shut down. It was determined that a mis-compare of the dual actuators caused the shut down. At failure the aircraft pitched nose down following the trailing trailing edge down movement of approximately 3 to 4 degrees. We manually set the stabilator to 3 degrees trailing edge down and continued to the Sikorsky Plant where a relatively normal landing was made. The only anomaly being a little greater nose up attitude during approach and landing..

Wasn't there an accident in the late 1970's that put one aircraft in the water in a similar manner to this latest accident?

It might have been at PAX River....but had two Sikorsky Pilots onboard?

Found it....not at PAX River....but near the Factory.

https://aviation-safety.net/wikibase/77705

it’s like 737Max decades earlier.

Another bit of information came to today....re the Rotor sounds on the audio.

The Main Rotor emits a N/Rev 4P 17.6hz sound but the tail rotor emits a slightly higher pulse of 21hz causing a problem telling the difference between them by ear. I am assuming that is during "normal operation" with standard Nr set by the Crew.

As poor as the one video is it can still provide a lot of information when examined by the investigators.