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Breaking News Thread
Krandall:
Maybe you can shed some light on this for me Brian...
how do you lose an aircraft in this day and age? Aren't all fflights tracked via radar? so they should have some sort of last known location? or what makes this so difficult?
Flynbyu:
--- Quote from: Krandall on June 05, 2009, 11:21:30 AM ---Maybe you can shed some light on this for me Brian...
how do you lose an aircraft in this day and age? Aren't all fflights tracked via radar? so they should have some sort of last known location? or what makes this so difficult?
--- End quote ---
You are tracked via transponder.....When you ask for permission to taxi to the active, the tower will assign you a transponder number....Cessna 204, taxiway Alpha, hold short runway 7 SQUAWK 2700. At that time you would repeat instructions, and set your transponder to "2700". That will identify you to ground and ATC. This number stays with you....until you change centers (ie-Minneapolis center, Dallas, Memphis) as you fly cross country. ATC will assign you a new number to track you as you change centers. When you are flying in the type of aircraft I fly, you can see it when you get pinged by radar. A yellow light flight flash or get brighter. Now if you CHANGE the transponder frequency, they will loose track of you and you will not be identified. You will be seen, but not identified. If you are highjacked, set transponder to 7500 and when you get pinged, you can be assured the military would be along side of you in minutes.
1200 is used in non-air controlled traffic, as a visual flight rule squawk....you need not not change it unless you are entering controlled airspace, and ATC assignes you a number. You must change it per ATC instruction.
The Airbus A330 is a fly by wire aircraft. No cables to rudders, etc. It's all electronic. It's all computerized, so it has several computers on board to back each one up in a failure. I've never heard of a complete failure. If you do loose power, there is a generator that pops out of the side of the aircraft, and turns an air driven turbine to power the system, so all the bases are covered. ATC can pinpoint the last location of the broadcast of the flight, which will get search and rescue close, but when you're at FL350, and at 500 mph, even at a high rate of descent you're still going to travel 50-100 miles from the last transmission. You can't descend too fast because it would rip the wings off at more than 10,000 feet per minute. When you get to VNE (Velocity NEVER EXCEED) speed, it's VERY dangerous. The aircraft could break apart and I think that's happened in this case. It became a lawn dart into the ocean tragically.
~Brian
There are
Peelz:
Lawn Dart? not sure I will ever fly again...thanks. :lol:
Flynbyu:
--- Quote from: PeelsSE2 on June 05, 2009, 12:04:03 PM ---Lawn Dart? not sure I will ever fly again...thanks. :lol:
--- End quote ---
If they had a loss of cabin pressure as reported by the aircraft's computers, you have a very short time to get to 10,000 AGL.
~Brian
Flynbyu:
RECIFE, Brazil – An Air France memo to its pilots Friday about the crash of Flight 447 said the airline is replacing instruments that help measure airspeed on all its medium- and long-haul Airbus jets.
Investigators have focused on incorrect speed readings as one potential factor in the crash.
With Brazil and France disagreeing about whether pieces of the jet have even been found in the Atlantic, investigators are using the last messages sent by the plane to determine the cause and try to avoid future disasters.
Air France declined to comment on the memo obtained by The Associated Press, saying it was for pilots only.
Airbus said the matter was part of the investigation into the crash that killed 228 people flying from Rio de Janeiro to Paris Sunday. The Bureau of Investigation and Analysis, which is leading the French probe of the crash, said it would address all questions at a Saturday news conference.
The memo sent Friday said Air France has been replacing instruments known as Pitot tubes and will finish in "coming weeks." It does not say when the replacement process started.
The plane's "black boxes" may be miles below the surface and investigators are looking for clues in the messages sent from the plane's computers just before it disappeared. One theory: the outside probes that feed speed sensors may have iced over, giving incorrect information to the plane's computers. The autopilot may have then directed the plane to fly too fast or too slow when it met turbulence from towering thunderstorms.
Airbus sent an advisory to airlines late Thursday reminding them how to handle the A330 in similar conditions.
The memo sent by Air France Friday says that a series of actions to reduce the risks of loss of airspeed information are being reinforced by "notably, the improvement of pitot models on Airbus' fleet of medium- and long-haul flights."
"On this topic, a program of replacing pitots with new models is under way," the memo reads. "It should be completed in coming weeks."
Pitot tubes are L-shaped metal tubes — about eight inches (20 centimeters) long on their longer side — that protrude from the wing or fuselage of a plane. The pressure of the air entering the tube lets sensors measure the speed and angle of the flight, along with less vital information like outside air temperature.
They are heated to prevent icing.
A blocked or malfunctioning Pitot tube could cause an airspeed sensor to work incorrectly and cause the computer controlling the plane to accelerate or decelerate in a potentially dangerous fashion.
Airbus said the French agency investigating the crash found that the doomed flight had faced turbulent weather and inconsistency in the speed readings by different instruments.
That meant "the measured air speed of the aircraft was unclear," Justin Dubon said.
In such circumstances, flight crews should maintain thrust and pitch and — if necessary — level off the plane and start troubleshooting, Dubon said.
Meteorologists said the Air France jet entered an unusual storm with 100 mph (160 kph) updrafts that acted as a vacuum, sucking water up from the ocean. The moist air rushed up to the plane's high altitude, where it quickly froze in minus-40 degree temperatures. The updrafts also would have created dangerous turbulence.
The jetliner's computer systems ultimately failed, and the plane likely broke apart in midair.
Brazilian officials have insisted for three days that military pilots have spotted wreckage from Flight 447 scattered across the ocean's surface. Air Force Brig. Gen. Ramon Cardoso again expressed confidence Friday that at least some of the objects — an airplane seat, a slick of kerosene and other pieces — are from the plane that vanished Sunday with 228 people on board.
"This is the material that we've seen that really was part of the plane," Cardoso said.
But ships guided by planes in the search area have been hampered by extremely poor visibility, and have recovered no wreckage. "We don't have any information yet that any of the ships are near any of the objects," Cardoso said.
The only piece retrieved so far, a cargo pallet, turned out to be sea garbage. Like other suspicious objects, it had to be hauled up and checked out, said Brazilian Navy Adm. Edson Lawrence.
French officials stopped short of criticizing their Brazilian counterparts, but France's Transportation Minister Dominique Bussereau said his own country's searchers have found no signs of the Airbus A330.
"French authorities have been saying for several days that we have to be extremely prudent," Bussereau told France's RTL radio. "Our planes and naval ships have seen nothing."
A French Defense Ministry official, speaking only on condition of anonymity because he was not authorized to speak publicly on the matter, also questioned the Brazilian claims, saying French teams "cannot precisely confirm the zone where the plane went down."
Cardoso also said a large oil slick spotted by search plane pilots was not from the Airbus, but that authorities believe another slick of kerosene was probably from the downed passenger jet.
France is sending a submarine to the zone where the plane is thought to have gone down to detect signals from the two black boxes, said military spokesman Christophe Prazuck. The Emeraude, already in the Atlantic, will arrive next week, he said. The vessel, which can dive up to 980 feet (300 meters) is to be used to help try to detect the signals noises from the boxes — believed to be up to 13,100 feet (4,000 meters) underwater. It will try to capture the acoustic signals, which can last 30 days, Prazuck said.
The Pentagon has said there are no signs terrorism was involved. Brazil's defense minister said the possibility was never considered. French Foreign Minister Bernard Kouchner agreed that there is no evidence supporting a "terrorism theory," but said "we cannot discard that for now."
Brazil's Air Force was flying relatives of victims to the search command post in the northeastern city of Recife Friday to tour the operation and ask questions. Recife has a large air force base where debris and any human remains would be brought.
Great job Pentagon....as if we didn't already know that.
~Brian
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