Wilcharl From United States of America, joined Jun 2000, 1166 posts, RR: 3 Posted (13 years 9 months 1 week ago) and read 1418 times:
To all the captains out there... Do you think the Captain of the AA MIA incidnet made a bad call when the evacuation was ordered?
From the NTSB's initial synopsis:
"About 2 minutes after landing, the fire commander reported no signs of fire and stated they would follow the aircraft to the gate. About 1 minute later, the captain reported he had a fire and that they would evacuate the aircraft. "
A class i took last semiseter on Accident and Emergancy mgt. initaily lead me to beleive this was a bad call on the captain. We all know that when you pop the slides there are going to be broken bones. If the fire did not appear inside the aircraft until 3 minutes after touchdown, I would think that it wasnt that signifigent especialy considering the captains origional emergancy call did not even request for them to roll the equipment out. Unfortuantly the prelim NTSB report doesnt say how big the fire was inside. Ive participated in emergancy drills and studied how a textbook emergancy should be handled. I recall a DL 767 i beleive with an a magnesium fire on one of the engines. The ARFF units came up sprayed it down and the entire time the Captain talked to the fire crews and calmlily decided no need to pop the slides and taxied to the gate. We dont want another Saudi L-1011 or Air Canada DC-9 where an emergacny is ignored, but when do you make the call to pop the slides and do you think this was an unnececessary call? From news media reports, I got the idea that the fire guys were kind of shocked that the slides were comming out and they were doing an evacuation. In every drill i have been in, when they roled the firetrucks they also rolled the mobile stairs out. Obviously none of us were there, and dont know what was going threw the captain or the crews mind when it happend but Im just looking for others opinon of this judgement call. I also see the fear that the a/c was over pressurizing with a stuck cabin outflow valve but correct me if im wrong, doesnt the a/c have a release system of sorts that would keep the a/c from pressurizing its self to the point that it would burst. Also, stoping the engines would thus stop the pumping of air in, and the pressure would remain constant inside the cabin right? Im sure waiting for mechanics to come out and free the outflow valve would be out of the question and I dont know all the circimstances or data. Thanks for y'alls opinons
FDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 1, posted (13 years 9 months 6 days 14 hours ago) and read 1266 times:
Their was 2 strikes against the deceased F/A.
1) Airbus doors (pax and cargo) can be opened while positive differential pressure exists in the cabin. I researched the A300-600 maintenance manual but could not find how much a diff. press. it would take before the door wouldn't open.
2) Because of this very real possibility, a warning light is placed at all doors (by the little window) to warn the door operator that the a/c is still pressurized. A potentially lethal situation if you're opening the door from the outside and the door hits you. And from the inside as we've seen with this incident. BUT, the design of the light circuit is such that the warning light is operational only if the door evac. slide is DISARMED.
Being that the door was armed he might not have realized the potential danger.
J32driver From United States of America, joined May 2000, 399 posts, RR: 1
Reply 2, posted (13 years 9 months 6 days 10 hours ago) and read 1241 times:
What's the designer's logic of allowing an airplane to remain pressurized on the ground? Most airplanes, at least the 2 airliner's I've flown (BAe J32, BAe 146), cannot remain pressurized on the ground. The squat switches open the outflow valves upon landing. I understand it to be a safety function to prevent the type of accident we are talking about.
As far as when to evacuate an airplane due to fire? This of course is personal judgement. If the fire is outside in an engine or apu, then let CFR deal with it and keep the passengers inside. If the fire is in the cabin, pop the slides and get the hell out! Small fires produce lots of smoke, and the smoke is what kills everyone.
What was the specifics on the AA accident? I haven't read anything on it yet.
FDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 3, posted (13 years 9 months 6 days 3 hours ago) and read 1216 times:
Airbus, Boeing and MDD all have pressurization schedules that during landing, the cabin altitude is slightly below field elevation and then the cabin depressurizes at a controlled rate by the pressurization controller. Interestingly the NTSB report stated the a/c was having pressurization problems as the initial reason for turnback to MIA.
I've read several reasons why A,B and MDD designed the pressurization schedules to remain pressurized during landing. MDD in their maint. manual explains it's to ensure smooth control of cabin pressure during pressure disturbances at the outflow valve during reverse thrust appllication.
Boeings reason to prepressurize during T/O and retain residual pressure during landing is to prevent an uncomfortable bump in cabin pressure caused by ram air impinging on the outflow valve.
CdfMxTech From United States of America, joined Jul 2000, 1341 posts, RR: 27
Reply 4, posted (13 years 8 months 4 weeks 1 day 4 hours ago) and read 1153 times:
Now I know at times with Boeing and Airbus...it's like comparing apples and oranges, but figure this out. On most Boeings, the outflow valve will transition to ground moddew with either or both WOW or wheel spin up signals (actually wheel spin-down). At this point the outflow valve will transition to full open - while not exceeding cabin rate limits. This happens rather quick - even if the aircraft enters and off - schedule descent. Now I will assume that the Airbus has some differences, but it was also probably on the gnd for more than 3 minutes before they shut down the engines and called for evacuation. Now, why was this aircraft still pressurized (if it was).
AAR90 From United States of America, joined Jan 2000, 3471 posts, RR: 47
Reply 5, posted (13 years 8 months 4 weeks 1 day ago) and read 1142 times:
Having spent too many years investigating too many mishaps, one learns not to second guess the crew but rather one attempts to understand what information was being presented to the crew and in what format. The captain believed there was a fire, but there is no indication in what format that information was being presented to the captain and on what he based his decision to evacuate the aircraft. All we know is that he stated he had a fire and he decided to evacuate the aircraft. Why is unknown.
As to why the aircraft did not depressurize, here is one theory being put forward (again, nothing official):
Blocked Pressure Valves Could Have Led To Death Of Flight Attendant
Dec 4, 2000
Insulation blankets left unfastened in the cargo hold of an American Airlines plane partially blocked both valves that control cabin pressure and possibly contributed to the death of a flight attendant during an emergency evacuation.
Jose Chiu, 34, died from injuries he suffered when the left front door of the Airbus A300 "exploded open" and he was thrown to the ground at Miami International Airport, the National Transportation Safety Board's (NTSB) preliminary report shows.
The plane's captain, Neal Talbot, 44, had reported trouble pressurizing the Airbus A300 shortly after departure from Miami for Port-au-Prince, Haiti.
After returning to Miami for an emergency landing, the captain said he was unable to depressurize the plane, and then ordered an evacuation because he believed there was a fire on board, the NTSB report says.
Passengers described a crushing sensation caused by mounting cabin pressure, as flight attendants struggled to open the doors. Finally, Chiu, the lead attendant, pried open the door and was catapulted an estimated 40 feet or more from the plane.
Jorge Prellezo, NTSB regional director, said the insulation blankets, normally secured with plastic fasteners, were somehow dislodged and partially obstructed the pressurization valves in the plane's cargo hold.
The rear valve was found about 90 percent blocked while the front valve was about one-third blocked, said Jeff Kennedy, air safety investigator for the NTSB, who is leading the investigation.
The heavy blankets, which insulate the cargo area, were two or three feet out of their normal position, Prellezo said. They are supposed to be fastened to the wall as a maintenance procedure.
The plane's flight to Port-au-Prince was its first after undergoing two days of undisclosed maintenance at American Airlines' Miami hangar.
While Prellezo called the finding regarding the blankets "significant," he said it did not entirely cause the pressurization problem. "We're looking at the procedures the crew was using," he said.
"The pressurization system is a complex system with many components, and we need to see exactly what went wrong to cause the problem."
The plane is now at American's maintenance base in Tulsa, Okla., being tested.
*NO CARRIER* -- A Naval Aviator's worst nightmare!
Wannabe From United States of America, joined Jun 1999, 677 posts, RR: 3
Reply 6, posted (13 years 8 months 3 weeks 4 days 12 hours ago) and read 1103 times:
I have it from good sources that the pilot was getting a smoke/fire indication from a lavatory smoke detector. They were also having difficulties with the pressurization of the cabin, so he was not entirely sure of what he was dealing with, so he had to assume that there was possibly a fire somewhere on board the aircraft. Given this, he was doing the safest thing possible by evacuating the aircraft as soon as he could. We have all seen how quickly an aircraft fire can get out of control, so I would never second guess him for this decision.
On Friday night I flew from SJU (San Juan, PR) to EWR on an AA A-300 in the aft emrgency exit row. The exit has two controls that I saw. The first arms the slide mechanisim. This is done by an FA just prior to departure. A lock pin with a red flag is removed from the arming mechanism, and the lever is moved forward to the armed position. The second control is the opening mechanisim. This is a handle which is shielded with a plastic (NOT CLEAR) cover on which the directions are written. The directions say;
To open door;
1. Remove plastic cover.
2. Move handle up to the open position
3. Push door firmly out.
It's this third line that struck me odd after reading several threads on this incident. From what I understand, these doors have a "power assist" that helps swing the door open. If you followed the directions on the handle and pushed firmly, you could follow the door open and be out before the slide could deploy. Nowhere was there a warning telling you that once opened, you will be facing a 20 foot drop to the ground. I would be wary in ANY situation where I was opening a door or hatch so far above the ground. Can anyone tell me why there is no better warnings on this particular door?
One other editorial note; The amount of instructions given to passengers who sit in emergnency row seats is a joke. I usually ask for emergency row seating because it gives me a few extra inches of legroom to fit my 6'2" frame into. I always make sure that I read not only the card, but also the directions on the door. These directions can change from airline to airline even on though the equipment may be the same. I have never received any verbal instructions from a crew member on how to open a door or what to do once I open it. There should either be a special emergency procedures card in those seats, or a specific set of instructions given to passengers who sit in those rows.
VC-10 From United Kingdom, joined Oct 1999, 3701 posts, RR: 34
Reply 7, posted (13 years 8 months 3 weeks 4 days 10 hours ago) and read 1093 times:
Hindsight (Monday morning quarter-backing ? ) is a wonderful thing. I bet if the Capt had kept everyone on board and a fire did ensue, this forum would be full of questions about why the Capt didn't deploy the slides.
Viflyer From US Virgin Islands, joined May 1999, 500 posts, RR: 0
Reply 9, posted (13 years 8 months 3 weeks 3 days 8 hours ago) and read 1064 times:
Nope...your wrong, our FA SOP says in a planned emergency evacuation (In that there is time to create a plan), that you are to breif one Pax per emergency exit. Usually you'll look for any deadheading FA/Pilot first, but you do not have one availabe to use your judgement, ask if they can open that exit, and tell them IF I AM NOT ABLE TO EVACUATE FROM THIS EXIT YOU WILL DO THE EVACUATION....but this is only in extreme situations and lets just say I know that happened on the AA A-300 no pax were briefed on opening the exit due to fact that situation did not warent it....