BA 2166 from Tampa
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Update: Caveat - What I've said here is wrong
Correct. Both aircraft must have the TCAS equipment fitted and operating for any TCAS alert to occur in either aircraft. Light aircraft would most likily NOT have a TCAS transponder fitted.
And yes, the quotes in the tabolid article as well as much of the rest of the content was taken straight from here - copy 'n paste style.
But of course not referenced, and rather made to sound like the copy&paster had done some investigative work which of course they hadn't.
And yes, the quotes in the tabolid article as well as much of the rest of the content was taken straight from here - copy 'n paste style.
But of course not referenced, and rather made to sound like the copy&paster had done some investigative work which of course they hadn't.
Last edited by 11K-AVML; 25th Oct 2006 at 17:33.
Hmm don't have the manuals with me but I'm not convinced by that statement. If the light aircraft had been squawking mode C then surely the the 777's TCAS would have been able to provide a TA/RA.
One eyewitness said: "I was on the Tampa flight. About 15 minutes into the climb the aircraft suddenly dropped out of the sky."
"Luckily all of other passengers were all still strapped in. But unfortunately the cabin crew were starting to prepare for service and were badly injured."
"At least four were so bad that they were unable to continue working."
The eye-witness said: "The captain came on and apologised saying that he had to take emergency evasion action to avoid a collision with another aircraft above him."
"There was a paramedic on board who apparently said 'It will be OK to continue but it was touch and go as to whether they return to Tampa."
BA confirmed that one of the forward Club class cabins was used as an impromptu sick-bay in which the injured stewardesses were treated and allowed to recuperate.
The eyewitness said: "I have been a frequent flyer for over 40 years and it is the scariest thing I have ever experienced."
"I'm off now to change my underwear."
"Luckily all of other passengers were all still strapped in. But unfortunately the cabin crew were starting to prepare for service and were badly injured."
"At least four were so bad that they were unable to continue working."
The eye-witness said: "The captain came on and apologised saying that he had to take emergency evasion action to avoid a collision with another aircraft above him."
"There was a paramedic on board who apparently said 'It will be OK to continue but it was touch and go as to whether they return to Tampa."
BA confirmed that one of the forward Club class cabins was used as an impromptu sick-bay in which the injured stewardesses were treated and allowed to recuperate.
The eyewitness said: "I have been a frequent flyer for over 40 years and it is the scariest thing I have ever experienced."
"I'm off now to change my underwear."
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ok
I got my "book" out and checked a few things...
one. TCAS can determine range and bearing even if mode "C" is not transmitted....it can show relative altitude if mode "C" is being transmitted.
selecting A or B ( above or below) can expand display to 8700' above or below when selected, while 2700' the other way.
and this is the gotcha: under normal conditions a "TA" will precede an "RA" by 15 seconds...this to give a chance to find visually the traffic.
while conceivably an intruder aircraft could turn on his transponder at the last second and offer less than the 15 second time warning, one wonders if the BA plane did get 15 seconds warning (TA) prior to the "RA".
does anyone know?
j
I got my "book" out and checked a few things...
one. TCAS can determine range and bearing even if mode "C" is not transmitted....it can show relative altitude if mode "C" is being transmitted.
selecting A or B ( above or below) can expand display to 8700' above or below when selected, while 2700' the other way.
and this is the gotcha: under normal conditions a "TA" will precede an "RA" by 15 seconds...this to give a chance to find visually the traffic.
while conceivably an intruder aircraft could turn on his transponder at the last second and offer less than the 15 second time warning, one wonders if the BA plane did get 15 seconds warning (TA) prior to the "RA".
does anyone know?
j
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Update: Caveat - What I've said here is wrong
The TCA System advises each pilot where the other a/c in their vicinity are and when alerting the pilots of the need for evasion action (RA) each TCAS unit involved will have and be communicating with each other so that the directions given do not conflict. If an aircraft were to be involved that did not have TCAS fitted, the available TCAS would not be able to determine what appropriate evasive action would be necessary.
I guess I should be more careful with my use of "TCAS alert"; I'm not aware of the ability of the system to use Mode C to advice of a conflict alert but I do have it on good authority that a RA will not be given without there being at least two TCAS units involved.
In the above posts it mentions the TCAS RA of descend descend descend. This would require two TCAS units to be involved.
BTW, I wouldn't put a Beechcraft King Air aircraft within my definition of a light aircraft. Although the model of the a/c involved hasn't been given, I would expect it to have TCAS as they do seem to be designed for passenger carrying purposes and similarly not simply private GA use.
(Caveat, I don't know the FAA regulations determining which a/c require TCAS as a mandatory condition).
The TCA System advises each pilot where the other a/c in their vicinity are and when alerting the pilots of the need for evasion action (RA) each TCAS unit involved will have and be communicating with each other so that the directions given do not conflict. If an aircraft were to be involved that did not have TCAS fitted, the available TCAS would not be able to determine what appropriate evasive action would be necessary.
I guess I should be more careful with my use of "TCAS alert"; I'm not aware of the ability of the system to use Mode C to advice of a conflict alert but I do have it on good authority that a RA will not be given without there being at least two TCAS units involved.
In the above posts it mentions the TCAS RA of descend descend descend. This would require two TCAS units to be involved.
BTW, I wouldn't put a Beechcraft King Air aircraft within my definition of a light aircraft. Although the model of the a/c involved hasn't been given, I would expect it to have TCAS as they do seem to be designed for passenger carrying purposes and similarly not simply private GA use.
(Caveat, I don't know the FAA regulations determining which a/c require TCAS as a mandatory condition).
Last edited by 11K-AVML; 25th Oct 2006 at 17:33.
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11k-avml
sorry pal, but your sources are wrong...a TCAS RA will be issued to the plane equipped with TCAS provided the intruder has transponder and mode c ( if it is a threat).
the OTHER plane does not need to have TCAS for the plane WITH TCAS to get an RA.
I am reading this from my tcas manual.
now if 2 planes both have TCASII the RA will be coordinated sending one plane up, the other down for example. this information is exchanged by mode S transponder.
j
sorry pal, but your sources are wrong...a TCAS RA will be issued to the plane equipped with TCAS provided the intruder has transponder and mode c ( if it is a threat).
the OTHER plane does not need to have TCAS for the plane WITH TCAS to get an RA.
I am reading this from my tcas manual.
now if 2 planes both have TCASII the RA will be coordinated sending one plane up, the other down for example. this information is exchanged by mode S transponder.
j
11k_AVML
Nope, not according to page 5 of the FAA's "Introduction to TCAS II, version 7".
Page 5 carries a matrix describing what advisories you get, depending on equipment fix. That source very clearly states that with TCAS II on one aircraft and a target aircraft squawking mode C or S you can get TA's and/or Vertical RA's.
Page 5 carries a matrix describing what advisories you get, depending on equipment fix. That source very clearly states that with TCAS II on one aircraft and a target aircraft squawking mode C or S you can get TA's and/or Vertical RA's.
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Nope, not according to page 5 of the FAA's "Introduction to TCAS II, version 7".
Page 5 carries a matrix describing what advisories you get, depending on equipment fix. That source very clearly states that with TCAS II on one aircraft and a target aircraft squawking mode C or S you can get TA's and/or Vertical RA's.
Page 5 carries a matrix describing what advisories you get, depending on equipment fix. That source very clearly states that with TCAS II on one aircraft and a target aircraft squawking mode C or S you can get TA's and/or Vertical RA's.
So much for recieving authoritive information - I'll remember that next time they tell me something!
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it is possible that BA was just a tad too aggressive in responding to the RA on the TCAS
I'm sure we have all done it, just sad that so many were hurt...any data on the accelerometers?
I'm sure we have all done it, just sad that so many were hurt...any data on the accelerometers?
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BA in Freefall!! Shock, Horror!!
I found this in todays Independant on-line. Did I miss anything interesting?
Published: 22 October 2006
A British Airways jet bound for London was forced into near freefall to avoid a mid-air collision over the US, the company said yesterday.
The pilot was being given instructions by air traffic control to continue climbing from 16,500ft to 20,000ft when the aircraft's emergency avoidance system gave the command "descend, descend, descend", a BA spokesman said.
And that's where it finished!!
Published: 22 October 2006
A British Airways jet bound for London was forced into near freefall to avoid a mid-air collision over the US, the company said yesterday.
The pilot was being given instructions by air traffic control to continue climbing from 16,500ft to 20,000ft when the aircraft's emergency avoidance system gave the command "descend, descend, descend", a BA spokesman said.
And that's where it finished!!
