40 Years Ago This weekend - American 191 at O’Hare
 

Here is the NTSB report:
https://www.ntsb.gov/investigations/...ts/AAR7917.pdf

What I found particularly sad about this accident is that the crew followed the correct procedures for loss (failure) of engine one. They had no idea they were dealing with loss (separation) of engine one.

Followed by More Death Eleven.

I lived in Chicago, Grand & Harlem, 9 sm from crash site. I had just started training for my private ticket. WOW. Didn't stop my training. Passed check ride in SF Bay area.

It completely consumed the public attention.

How could the crew know they needed twenty more knots.

And they probably died thinking they failed to adequately control the aircraft in an OEI scenario.

IIRC:- It was the slats retracting following loss of hydraulic pressure that caused the uncontrolled roll.
The engine attachment was modified first and then several years later the slat system had valves fitted to stop them retracting.

My photo of N110AA taking-off from O'Hare on 13 August 1973.


https://cimg6.ibsrv.net/gimg/pprune....e9a81924d9.jpg

In memory of all on board.

Boy, the picture of a $150 (probably smoked) ham overlying the last post is kinda disrespectful. Mods might want to watch that.

My grandparents lived in Maywood, IL, and we were having a weenie roast that afternoon in the forest preserve just to the east of ORD. (I was 15 at the time) My aunt Truelove and uncle Emil (who lived in the Toughy trailer park adjacent to the crash) were with us. We probably saw the takeoff, but the DC-10 made a lot less noise than most of the other hardware around at the time, so nobody was really looking, until there was a boom bigger than we were used to hearing (several years earlier) from all of the wonks from NAS Lakeview, and the military side of O'Hare "accidentally" breaking the sound barrier. This day, in addition to the noise, there was a big smoke cloud, and a fireball. Then we couldn't see much else. We finished our hotdogs, and tried to get out of the FP, but everything was blocked off. Got back to Maywood in the middle of the night with Truelove and Emil in tow. Found out two days later that they no longer had a house....

I just think it's cool that you have (had?) an aunt named Truelove.

I worked at a science lab that year in downstate Illinois, and the lab director was having a house-party that afternoon. I remember CBS "breaking in" on their regular programming with wall-to-wall coverage of AA191 (that was the year before CNN debuted).

At the time none of us had connections to aviation - but many had family or friends in Chi-town. The party became very quiet (and the BBQ was forgotten) as we just sat and watched the reporting.

Should be emphasized (it's in the report, of course) that an improvised engine maintenance procedure with a forklift damaged the aft pylon/wing attachment, which eventually broke under fatigue. When the engine came off, it took out the slat hydraulics - and also took with it Bus 1 power for the "slats disagree" warning and the sole stick-shaker (left seat). Crew simply had no chance of knowing what they were dealing with, flew correct engine-out procedure (climb at V2), and stalled the slatless wing. A particularly ugly coincidence of swiss-cheese holes.

Fate is the hunter..
 

I was on a business trip in The USA at that time, a family emergency occurred and I had to return home to Australia, the company that I worked for offered to fly me from Ohio in the company Saberliner to ORD to catch this flight, I thought this was too extravagant and declined, opting for an airline connection out of Dayton the next day....in 1973 in Sydney during my Commercial Licence training I had been enquiring about Instrument Rating Training at a flight school at Bankstown Airport, they offered me a chance to observe in a PA-30 but I had made arrangements to pick up my wife and declined the offer, the PA-30 had a mid-air collision with a deHavilland Dove, no survivors.....

Hydraulic Lines
 

I remember seeing DC-10s parked in large numbers while the FAA and NTSB were sorting out what to do. The San Diego 727 collision with a C-172 first hit by the nosewheel then hit the leading edge and took out all three hydraulic lines routed next to one another. The Sioux City DC-10 lost hydraulics when a piece of the #2 turbine disk went through the elevator.

Hard lessons.

I was told at the time that AA had installed a video camera on the flight deck so that the passengers could watch the pilots during the flight. If that is true, it does not bear thinking about.

I was in LA at the time. Friend was in publishing there. There was a publishers convention taking place and a number of attendees there were coming on the DC-10, you can imagine the cloud it cast over the event.

There are a number of photos of the accident occuring here, which don't seem commonly around (scroll halfway down).

The Ghosts of Flight 191 | Chicago magazine | May 2019

The fork lift approach was actually that for the rear, high up middle engine. It was apparently straightforward, while the wing engines were specified to need a complex cradle arrangement and more man hours to make a change. One would have thought that the manufacturer would anticipate someone adapting one method to the other, and thinking they were clever doing so. A specific "Never fork lift the wing engine in" instruction was needed. You can also argue that the mounting lugs should have been more robust, anticipating the forces when engines are put in place. A design attitude of "what could go wrong" as well as "what will work right".

I see nothing in the report that supports this. The report does discuss possible pilot actions in controlling the aircraft using various controls still working in this event

Before you get this all wrong I would like to comment.
The inspection being done was to inspect the pylon attachment pins.It saved several hundred man hours to leave the engine attached.
On the number 2 engine a forklift was used to lift a work platform that included the engine,a crew of mechanics and all of their tools. The engine was actually rolled into position on rails and was then lifted with come alongs with dynamometers attached to measure the force.

The reason the airplane crashed is because the slats retracted on the left wing and because these airplanes only had one AOA sensor and a single channel stall warning system that was powered by the number 1 generator which was on the engine that was lost.

I was PIC of a TWA 727 flight LAX-PHX-ICT-ORD. While in the ramp office at ICT I was advised we were on a ground hold because of an accident at ORD. I knew weather wasn't a factor because it was a very clear Spring day.

Before we were released we were advised that Runway 4R was closed because an engine from the DC-10 was on the runway. When we arrived we were assigned Runway 9L, which passes through the threshold of 4R. We were down to taxi speed by that point, and could clearly see the engine on the runway. My first cousin lived in Barrington, IL. Her 16 year old so had a part-time job with UAL catering. He was standing on the loading dock and saw the whole thing. It looked so close he thought he was going to die.

As I recall, MD argued that the chances of these systems failing at the same time was so remote that there was no need to have a physical system to prevent the slats from retracting on one side. It's a very difficult process as emotion runs high after the event.

I worked for UA and transferred to ORD in May of 1980, and worked on a crew with the guys that discovered the UA -10 that caused the grounding of the fleet when it was discovered to have an engine about ready to fall off. Those guys told me that Percy Wood, the CEO of UA came out to the field that night and asked the mechanics whether they thought the fleet should be grounded. Can you imagine an airline CEO doing that these days?

"Forklift Joe" Leonard, the father of this unapproved method, was "punished" by later being paid millions to be the CEO of AirTran. Got to love corporate America, kill hundreds, make millions.

I wonder if the CVR was censored. 31 seconds passed after the pilot said "Damn" when the engine separated. Long time.

Perhaps. But it seems at that point they knew they were about to die. What investigatory significance would be in anything said further?

As to the post that stated there was a flight deck camera viewed by the pax, I've heard that as well. It is a popular rumor, whether it's true I'm not sure.

As a frequent flyer in the early 80's American indeed had cockpit cameras available on channel 9 along with cockpit communication audio on most of the DC-10s.

Would it have been possible to detect the cracked or damaged pylon during a pre-flight walk around?

dg

No, not possible.

No - the affected bit of metal was 1) right at the pylon/wing-bottom interface, and also 2) covered by the fairing or "tailcone" skin of the pylon. Crew would need "x-ray vision."

Not to mention that that point is about 3.5m/12 feet above the ground, and a fatigue crack may be just a few mm long - right up until it lets loose completely under stress.

heard those stories about the PSA 727 domiciled in San Diego at the time, however looking at the last photo before she hit the ground, one can clearly see the rudder hard left, ailerons and spoilers commanding left wing down, and the elevators in a nose up position, the damage to the right inboard wing where the Cessna exploded on contact, (pictures and report make no mention of nosewheel ) caused too much damage for that wing to sustain flight...at the safety seminar where Al Haynes was a keynote speaker I had the privilege to attend, he showed us a diagram where the hydraulic lines in the horizontal stabilizer were penetrated, no mention of the elevator

and of course the "good" from all of this, the procedure to pitch up to reduce speed back to V2 (in effect at the time) was disappeared, and most flight director systems will maintain V2+10 if above...when the folk at American played this scenario out in the simulator, they crashed every time, when they left the airspeed where it was instead of pitching to reduce to V2, the airplane flew away, and they were able to return and land safely....so this accident has probably prevented more loss of life...and I think American subsequently refitted all their planes with the optional FO's column stick shaker, and systems mods were made to lock high lift devices "in position" in the event of loss of all hydraulic pressure

Think I read the CVR lost power after losing the engine.

nowadays they never step out of their office and only know how to say it was "pilots error"!

Reading through the accident report, I picked up on one point that I missed (or forgot) from reading the report years ago: only the captain’s control column had a stick shaker motor. A second stick shaker motor was available as an option for the FO’s control column, but AA didn’t select that option for its DC-10s. A post-accident DC-10 AD added the FO stick shaker.

Was a single stick shaker typical for transport category aircraft of that era?

That is true. AAL discontinued that practice after this crash.

Yes,all of the 737-200's and 727-200's along with the the DC-10's at the airline I worked for had a single AOA and single stick shaker.After this accident they all were modified to dual AOA's and dual channel stall warning systems.

aerolearner;

Thanks for posting that link to a detailed analysis of the maintenance procedure.

Cheers,
Grog

Corrections
 

The engine took out two of the three hydraulic systems not three. There were at least ten cracks found in the world's fleet after the grounding but not all were reported..fact.
the slat disagree light was a small blue one which was out of normal scan and was checked only on extension or retraction.
Souix city.
SR had number 2 go bang out of West Africa which took out two of the three systems before Souix city with one of the big chiefs flying it who was very competent. They were very lucky as the fan blade missed the third system but did take out the apu fuel line.
The undercarriage bay had all three lines around the side as well. On the ER version they put some armour type perforated sheet for protection in case of a tyre going bang.
Douglas were negligent in not having a slat locking system like wot uvva kites I drove.