CO Crash
- Thread starter flytchick
- Start date
Tug McGroin
Senior
I’d like to deviate from the protracted theories that excessive accumulations of ice on the wing’s leading edge and horizontal stabilizer degraded airfoil/s performance to the point that the airfoil/s experienced a classic and unrecoverable low altitude aerodynamic stall.
I'm hoping an experienced Dash 8-400 Pilot and/or Avionics Technician will provide some information about the Dash 8-400 digital flight control, autopilot and air data systems. Until that time comes, I'm basing my comments on my experiences with fly-by-wire digital flight control systems, autopilots and air data systems.
As I understand it, the Dash 8-400 autopilot is coupled to proven, state-of-the-art digital flight control system computers that constantly interrogate flight control surface positions and feedback as well as numerous aerodynamic static and pressure sensor inputs. Engine FADEC data is also interpreted by the digital flight control system to minimize compressibility drag, avoid buffet, and to counter any negative impact of the much higher slipstream swirl induced by the propellers.
That being said, does the Dash 8-400 digital flight control system have a degree of "Alpha Floor Protection� As a matter of certification, the Air Data System has to have multiple, independent pressure and static sensor sources as well as redundant AOA sensor input. Does the Dash 8-400 incorporate ADS “smart probe†technology, or are the sensors / vanes separate?
Following normal operational procedures, I can only assume that the Captain’s and First Officer’s flight control system displays use separate and independent ADS sources. Other than obvious observed flight control system display information errors between the Captain and First Officer, what warning messages are displayed to alert the flight crew that an ADS source has failed?
When the digital flight control system computers sense a failure of an ADS source, is alternate ADS source selection automatic or does it require manual intervention on the part of flight crew members? In addition, I would think that if the autopilot is selected to the failed ADS source, another manual flight crew intervention would be required to assure the autopilot is using an operable ADS source.
It seems highly unlikely that an aircraft with fully operational flight control system computers, coupled to a digital autopilot system with both coupled to true and accurate ADS source information could penetrate into an aerodynamically unstable flight regime without the digital flight control system "Alpha Floor Protection" mode exercising authority.
ADS source failure (heater and/or probe) and the flight crews inability to quickly rectify the situation during a critical phase of the flight could result in PIO and a full aerodynamic stall. Game Over!
I'm hoping an experienced Dash 8-400 Pilot and/or Avionics Technician will provide some information about the Dash 8-400 digital flight control, autopilot and air data systems. Until that time comes, I'm basing my comments on my experiences with fly-by-wire digital flight control systems, autopilots and air data systems.
As I understand it, the Dash 8-400 autopilot is coupled to proven, state-of-the-art digital flight control system computers that constantly interrogate flight control surface positions and feedback as well as numerous aerodynamic static and pressure sensor inputs. Engine FADEC data is also interpreted by the digital flight control system to minimize compressibility drag, avoid buffet, and to counter any negative impact of the much higher slipstream swirl induced by the propellers.
That being said, does the Dash 8-400 digital flight control system have a degree of "Alpha Floor Protection� As a matter of certification, the Air Data System has to have multiple, independent pressure and static sensor sources as well as redundant AOA sensor input. Does the Dash 8-400 incorporate ADS “smart probe†technology, or are the sensors / vanes separate?
Following normal operational procedures, I can only assume that the Captain’s and First Officer’s flight control system displays use separate and independent ADS sources. Other than obvious observed flight control system display information errors between the Captain and First Officer, what warning messages are displayed to alert the flight crew that an ADS source has failed?
When the digital flight control system computers sense a failure of an ADS source, is alternate ADS source selection automatic or does it require manual intervention on the part of flight crew members? In addition, I would think that if the autopilot is selected to the failed ADS source, another manual flight crew intervention would be required to assure the autopilot is using an operable ADS source.
It seems highly unlikely that an aircraft with fully operational flight control system computers, coupled to a digital autopilot system with both coupled to true and accurate ADS source information could penetrate into an aerodynamically unstable flight regime without the digital flight control system "Alpha Floor Protection" mode exercising authority.
ADS source failure (heater and/or probe) and the flight crews inability to quickly rectify the situation during a critical phase of the flight could result in PIO and a full aerodynamic stall. Game Over!
nostradamus
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I would like to insert a protracted device into you, in a membrane of my choice and study your arrogance sir.
Point is, this fully operational, experienced, coupled to the human race and not aerodynamically or politically correct pilot says that this just happened a few days ago. If you think that powerful interests will not try to steer this investigation to their favor..,,,,,,,,....,. Follow the money sir, and you will meet the financial owners of the perceived truth.
Tug McGroin
Senior
You’ve got the talking done Nostradamus. You might be very disappointed in the outcome of your proposition to stick anything anywhere in my body.
It’s not me making outrageous and totally false statements about accident causes. If conspiracy theories entertain you, I suggest you start with the Humpty Dumpty was pushed theory.
FrugalFlyerv2.0
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Although Bombardier is well connected politically, I just don't see them behaving like Europeans (i.e. Airbus) - but I could be wrong.
nostradamus
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Do you agree with this nostradamus?
Henson Aviation/Piedmont Airlines has been flying the Dash-8 series for more than 24-years in icing conditions and has never lost a Dash-8.
nostradamus
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When a former NTSB leader requests that a type of airplane should be grounded and the present NTSB leaders want to blame the pilots, within a week of their investigation, it raises a big red flag.
Implicating pilots or manufacturers for an accident in less than a week from any occurrence, is unprofessional, irresponsible and should not garner respect or faith in the present leaders of this organization.
The link below should make the flying public and the families of this most recent tragedy, feel uncomfortable, in my opinion. To implicate pilots and start working for an aircraft manufacturer within a week is evidence that someone has their best interests in mind, not those that no longer have a say in this matter.
Asked whether the pilot might have overreacted by pulling the stick back when it automatically went forward, Chealander said, "Yes, it's possible."
NTSB board member on Buffalo case going to work for Airbus
nostradamus
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The stretch version of the Dash 8 is the Q400, it is similar in design to the stretch version of the ATR 42, the ATR 72, which was involved in a similar accident.
The ATR 72 is only flown in the Florida and Islands south of it to keep it out of icing conditions.
BoeingBoy
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nostradamus
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False.
Not only does Eagle fly them out of sometimes icy DFW but Eagle flew them from ORD during the winters of 1995-2000 until all Eagle ops at ORD were regional jettified.
Eagle moved the ATRs out of ORD for the winter of 1994-95 while the de-icing boots were modified. But in late 1995, they were back at ORD.
nostradamus
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Alpa President John Prater, before the senate subcommittee recently.
"We do note, however, possible similarities with previous accidents. Recent media reports and a review of NTSB reports bring to mind events such as the crash of a Jetstream 4101 in Columbus, Ohio in January 1994, an ATR 72 which crashed in Roselawn, Indiana in 1994,"
Captain John Prater, president of ALPA, address to the Senate Subcommitee.
ALPA showing support against the blame the pilots faction. Baby steps, but commendable.
"We do note, however, possible similarities with previous accidents. Recent media reports and a review of NTSB reports bring to mind events such as the crash of a Jetstream 4101 in Columbus, Ohio in January 1994, an ATR 72 which crashed in Roselawn, Indiana in 1994,"
Captain John Prater, president of ALPA, address to the Senate Subcommitee.
ALPA showing support against the blame the pilots faction. Baby steps, but commendable.
FrugalFlyerv2.0
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Colgan Air Transcript Shows Lack Of Crew Discipline
By Andy Pasztor
Of The Wall Street Journal
WASHINGTON (Dow Jones)--The pilots of the Continental Connection turboprop that crashed in February near Buffalo N.Y., rushed through mandatory checklists in a matter of seconds, but spent almost the entire 59-minute flight from Newark, N.J., bantering about personal issues, job goals and the theoretical hazards of ice accumulation during winter flying, according to the cockpit recorder transcript released Tuesday by federal investigators.
The transcripts shows that the Colgan Air Inc. crew, Capt. Marvin Renslow and co-pilot Rebecca Shaw, violated mandatory safety rules by discussing extraneous topics during the descent to Buffalo, just before their twin-engine Bombardier Q400 aircraft slowed dangerously and went into an aerodynamic stall, killing 50 people.
Data released by the National Transportation Safety Board indicates that the stall wasn't triggered by ice accumulation, but rather Capt. Renslow's pulling back on the controls and overpowering an automatic stall-protection system that was pushing the nose of the plane down in order to regain a safe flying speed.
The transcript of conversations reflects a breakdown in cockpit discipline, marked by an almost cavalier attitude toward safety as the pilots laughed and joked extensively about previous flying experiences, the rigors of commuting to work by air and their own shortcomings as aviators.
Rest of Story
By Andy Pasztor
Of The Wall Street Journal
WASHINGTON (Dow Jones)--The pilots of the Continental Connection turboprop that crashed in February near Buffalo N.Y., rushed through mandatory checklists in a matter of seconds, but spent almost the entire 59-minute flight from Newark, N.J., bantering about personal issues, job goals and the theoretical hazards of ice accumulation during winter flying, according to the cockpit recorder transcript released Tuesday by federal investigators.
The transcripts shows that the Colgan Air Inc. crew, Capt. Marvin Renslow and co-pilot Rebecca Shaw, violated mandatory safety rules by discussing extraneous topics during the descent to Buffalo, just before their twin-engine Bombardier Q400 aircraft slowed dangerously and went into an aerodynamic stall, killing 50 people.
Data released by the National Transportation Safety Board indicates that the stall wasn't triggered by ice accumulation, but rather Capt. Renslow's pulling back on the controls and overpowering an automatic stall-protection system that was pushing the nose of the plane down in order to regain a safe flying speed.
The transcript of conversations reflects a breakdown in cockpit discipline, marked by an almost cavalier attitude toward safety as the pilots laughed and joked extensively about previous flying experiences, the rigors of commuting to work by air and their own shortcomings as aviators.
Rest of Story
