TCAS

Question 1

TCAS provides

Answer 1

3-D traffic position info and possibly avoidance actions in case of a collision threat

Question 2

TCAS creates 2 3D protective bubbles and reacts to intruders

Answer 2

inner - 15-30 secs before collision: RA
outer- 30-40 secs- TA
timings based on:
closest point of approach (CPA)
time to closest point of approach

Question 3

TCAS components

Answer 3

2 directional antenna
TCAS computer
transponder

Question 4

TCAS 1

Answer 4

oldest version
display of nearby traffic
produces traffic advisory TA
does NOT give an escape manoeuvre

Question 5

TCAS 2

Answer 5

Gives TA's
also gives RA's for very close traffic 
RA's only in vertical plane 
requires mode S transponder 
display will be on ND & PFD(on vsi)
system does NOT guarantee a particular separation

Question 6

TCAS inputs

Answer 6

radio alt
config
ADC

does NOT take stall speed into account

Question 7

TA- traffic advisory

Answer 7

if an intruder system will tell you "traffic traffic"
intruder colour coded
pilot reaction:
cover controls 
look for intruder
NO avoidance action

Question 8

RA- resolution advisory

Answer 8

corrective RA:
requires avoidance manoeuvre
“climb climb”
“descend descend”
“climb crossing climb”- climb through other a/c alt
“climb climb now”- reversal of previous order
pilot action: follow avoidance commands & advise ATC
- follow TCAS not ATC

preventive RA:
other a/c close enough to trigger but no manoeuvre needed
“monitor vertical speed”

Question 9

“clear of conflict”

Answer 9

pilot should promptly return to their previous clearance and inform ATC

Question 10

TCAS display

Answer 10

2-D a/c position if the other has mode A transponder
3-D position if other a/c has mode C or S
could have dedicated display or part of EFIS(ND & PFD)

Question 11

TCAS ND symbols

Answer 11

white diamond unfilled = other traffic (up to 40Nm range)
white diamond filled = proximate traffic, within 6Nm +- 1200ft
amber circle - traffic advisory 30-40 secs
red square - resolution advisory 20-30secs

Question 12

TCAS what will you get? both a/c mode S

Answer 12

co-ordinated RA

Question 13

TCAS what will you get? you have mode S other a/c has C

Answer 13

you get RA, they get nothing or TA if they have TCAS 1

Question 14

TCAS what will you get? you have mode S other a/c has mode A

Answer 14

you get a TA, they get nothing

Question 15

TCAS erroneous activation

Answer 15

when climbing towards a safe altitude but aircraft above (at a safe level)
climbing too quick could activate TCAS despite you being safe
therefore the VS autopilot mode should be used