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Posted
3 hours ago, A64Pilot said:

I don’t want a job with the FAA and I’m not steeped in ACM, but we did train for it in the late 80’s because at that time the USSR was developing a helicopter specifically to shoot us down, Army quickly for whatever reason quickly backed out of ACM, and never really fielded air to air weapons for the AH-64. Good thing I guess because the air to air threat never materialized. Their stated concern was airframe fatigue but later testing found that not to be a concern, largely because helicopters simply can’t generate the G forces a fixed wing can.

However you didn’t answer the question, was the Copilot trained to motor the rudder full travel back and forth when encountering turbulence?

This if accurate seems to indicate several issues, training is one, any time it’s pilot error it’s a training failure, but aircraft design and apparently mis programmed simulators as well as other factors were in play, many other factors. 

https://en.wikipedia.org/wiki/American_Airlines_Flight_587

Hopefully no one actually trained him to bury the rudder pedals to full deflection. 

I hate to dash your hopes but the original FAA syllabus was encouraging, indeed saying pilots did not use the rudder sufficiently saying the "rudder is a powerful tool that is under utilized."

Now Boeing airplanes could swing stop to stop which is not required under FAR Part 25 because Boeing had internalized a military specification dating all the way back to the B-47. Boeing said, if they had been aware of this internalization on their commercial aircraft they would not have designed them so robust. The 787 is not so robust, but everything up through the 777 is so designed. 

I would suggest a reading of the NTSB report. In it, you will find Airbus technical pilots, like me had real concerns about the mandated training and the methods contained therein but were basically hog tied by the FAA in their demands to for instance recover from a 90 degree bank roll in wake turbulence. Wide bodies don't get to 90 degrees in a wake turbulence encounter. A fair reading will reveal the training was inappropriate

From the report:

In a May 22, 1997, letter to the chief test pilot at Airbus, an American Airlines A300 technical pilot indicated his concern that AAMP handout pages stated that “at higher angles of attack, the rudder becomes the primary roll control.” The technical pilot’s letter also expressed concern that “the program infers that aileron application in these situations is undesirable since it will create drag caused by spoiler deflection.” Further, the letter stated that the AAMP instructor had been teaching pilots to use the rudder to control roll in the event of a wake turbulence encounter. The American Airlines A300 technical pilot asked the Airbus chief test pilot for his thoughts on this subject and suggested a teleconference a few days later. In a May 23, 1997, facsimile, the chief test pilot stated that he shared the A300 technical pilot’s concern about the use of rudder at high AOAs and agreed to a teleconference to discuss the matter.

"

Posted
10 hours ago, GeeBee said:

I hate to dash your hopes but the original FAA syllabus was encouraging, indeed saying pilots did not use the rudder sufficiently saying the "rudder is a powerful tool that is under utilized."

Now Boeing airplanes could swing stop to stop which is not required under FAR Part 25 because Boeing had internalized a military specification dating all the way back to the B-47. Boeing said, if they had been aware of this internalization on their commercial aircraft they would not have designed them so robust. The 787 is not so robust, but everything up through the 777 is so designed. 

I would suggest a reading of the NTSB report. In it, you will find Airbus technical pilots, like me had real concerns about the mandated training and the methods contained therein but were basically hog tied by the FAA in their demands to for instance recover from a 90 degree bank roll in wake turbulence. Wide bodies don't get to 90 degrees in a wake turbulence encounter. A fair reading will reveal the training was inappropriate

From the report:

In a May 22, 1997, letter to the chief test pilot at Airbus, an American Airlines A300 technical pilot indicated his concern that AAMP handout pages stated that “at higher angles of attack, the rudder becomes the primary roll control.” The technical pilot’s letter also expressed concern that “the program infers that aileron application in these situations is undesirable since it will create drag caused by spoiler deflection.” Further, the letter stated that the AAMP instructor had been teaching pilots to use the rudder to control roll in the event of a wake turbulence encounter. The American Airlines A300 technical pilot asked the Airbus chief test pilot for his thoughts on this subject and suggested a teleconference a few days later. In a May 23, 1997, facsimile, the chief test pilot stated that he shared the A300 technical pilot’s concern about the use of rudder at high AOAs and agreed to a teleconference to discuss the matter.

"

I seem to recall that particular airframe (the accident airframe) had previous damage and repair to the vertical stab composite structure.  I seem to recall it was deemed not a factor, but it always seemed like too much of a coincidence to me. Do I recall that correctly?

Posted
30 minutes ago, takair said:

I seem to recall that particular airframe (the accident airframe) had previous damage and repair to the vertical stab composite structure.  I seem to recall it was deemed not a factor, but it always seemed like too much of a coincidence to me. Do I recall that correctly?

You do recall that correctly and the materials and engineering folks at NTSB said it was not a factor. I have to defer to their judgement.

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Posted

There is a difference between teaching to use full rudder in a serious upset condition and walking the rudders to deal with minor wake turbulence.

A single use in a serious upset should be fine. 

Posted

I find it annoying when people says things like...

"It is no wonder that today's pilots, Commercial as well as GA, cannot hand fly a plane if the autopilot fails."

"We just keep dumbing down pilots.  Pretty soon newly minted pilots as well as the old ones that become dependent upon that latest glass from Garmin will only be able to land with Garmin Auto Land....."

It's inappropriate to explicitly attribute characteristics to an entire population.

 

The flight 587 accident was about a lot more than just the abuse of the rudder.   "Contributing factors were characteristics of the Airbus A300-600's sensitive rudder system design" - Airbus had made a design change the to rudder control system that changed the gearing and increased rudder travel for a given pedal travel.  Normally as airspeed increases the rudder ratio is decreased.    The authority available was not safe.

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Posted
3 minutes ago, skykrawler said:

I find it annoying when people says things like...

"It is no wonder that today's pilots, Commercial as well as GA, cannot hand fly a plane if the autopilot fails."

"We just keep dumbing down pilots.  Pretty soon newly minted pilots as well as the old ones that become dependent upon that latest glass from Garmin will only be able to land with Garmin Auto Land....."

It's inappropriate to explicitly attribute characteristics to an entire population.

 

The flight 587 accident was about a lot more than just the abuse of the rudder.   "Contributing factors were characteristics of the Airbus A300-600's sensitive rudder system design" - Airbus had made a design change the to rudder control system that changed the gearing and increased rudder travel for a given pedal travel.  Normally as airspeed increases the rudder ratio is decreased.    The authority available was not safe.

I would tend to agree, but the entire training regimen that was the result of as you said, "explicitly attribute characteristics to an entire population." that lead to this abuse.

Posted

I’ve known Monroe McDonald since the 1980’s as a ham operator I used to talk to every day on the way to and from work. I recognized his distinctive voice on the LiveATC recording. 

I flew in the BD-4 he built way back then and kept at a hangar in Addison in the days when you could afford one there . He was very familiar with the entire area around Addison.

Most people may not know he’s the guy who proved with tufting that the airflow in an M20C is OUT of the oil cooler and had built a plexiglass duct to mount on front of the oil cooler intake hole to force the air to flow IN.

The last ADS-B datapoint I saw showed a 1000fpm climb rate and a very slow ground speed. The accident occurred near the end of civil twilight IIRC. I’ll let the investigation play out.

Rest in peace Monroe, K5DUS SK

 

 

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Posted
On 12/5/2023 at 6:22 AM, takair said:

I seem to recall that particular airframe (the accident airframe) had previous damage and repair to the vertical stab composite structure.  I seem to recall it was deemed not a factor, but it always seemed like too much of a coincidence to me. Do I recall that correctly?

I hadn't heard this but I've always thought just this one incident might not have been the entire cause...and that there was probably structural weakening over time and this was the "final straw".

Posted

NTSB Prelim:

Multiple witnesses reported seeing the airplane attempt to land on runway 34 at Air Park –
Dallas (F69) and subsequently perform a go-around. During the go-around, the witnesses
observed the airplane’s left wing dip perpendicular to the ground and enter a near-vertical
descent. Several surveillance cameras also captured the landing, go-around, climb, wing dip,
and descent toward terrain.

The engine separated from the fuselage and the
engine and propeller were embedded about 2 ft into the ground just north of the main
wreckage.

 

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/193411/pdf

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  • 1 month later...
Posted

I don’t know if it had anything to do with Boeing overbuilding rudders or not, but a few early model B-52’s broke up in air in turbulence when the rudder came off, they weren’t walking the rudder, turbulence broke it off.

They used to fly the Chrome Dome missions out of my home town, and one of those on the way back home got into bad weather, broke up I think maybe in North Carolina and of course it was armed with nuke(s). Several of the crew members made it out and I think from memory a couple survived the parachute ride but froze to death because it was Winter.

I think Part of the fix was to remove several feet of the vertical. The old adage is you can’t give a pilot too much tail and I think Boeing was a firm believer, most of their designs had huge verticals.

Found it, it was Maryland. 
I think this crash ended Chrome Dome and Nukes were no longer continuously airborne.

https://aviation-safety.net/wikibase/48311

Posted
56 minutes ago, A64Pilot said:

I don’t know if it had anything to do with Boeing overbuilding rudders or not, but a few early model B-52’s broke up in air in turbulence when the rudder came off, they weren’t walking the rudder, turbulence broke it off.

They used to fly the Chrome Dome missions out of my home town, and one of those on the way back home got into bad weather, broke up I think maybe in North Carolina and of course it was armed with nuke(s). Several of the crew members made it out and I think from memory a couple survived the parachute ride but froze to death because it was Winter.

I think Part of the fix was to remove several feet of the vertical. The old adage is you can’t give a pilot too much tail and I think Boeing was a firm believer, most of their designs had huge verticals.

Found it, it was Maryland. 
I think this crash ended Chrome Dome and Nukes were no longer continuously airborne.

https://aviation-safety.net/wikibase/48311

This one landed with no tail…

https://theaviationist.com/2021/01/11/that-time-a-b-52h-stratofortress-bomber-lost-its-tail-over-new-mexico-but-managed-to-land-6-hours-later/
 

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Posted

Did you read why it was flying?  Go out and look for something and sometimes you find it. They were very luck and good.

I think from memory that 8 ft was cut off of the tail after the determination was made that making it strong enough would be too heavy and about the same time the ailerons were disabled, a Buff has no aileron control anymore. I think the ailerons were fatiguing the spars and it was a life extension issue.

All this is from memory so I could be way off.

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