Narrative:

I am writing to note problems with TCASII displays. My company has installed TCASII in all of our J31 aircraft to comply with recent TCASII requirements. The TCASII information is displayed on a collins wxr-270 radar screen. I have had several problems with receiving TA's from TCASII and being unable to determine the position of the traffic because the screen was unreadable with direct sunlight on the screen or bright sunlight in the cockpit. I spoke with our maintenance department and they advised me that wxr-270 radar screen was designed for viewing during overcast days or at night when pilots would be using it to avoid WX. During bright sunny days, you must cup your hands over the screen to see the TCASII display. I have had several incidents where we got a 'TA' but were unable to determine the position of the traffic because of this problem. Today, I was at 400 ft AGL when I experienced this problem on the takeoff. I would like to suggest that the TCASII information be displayed on a higher quality screen or on a more reliable source that is not affected by bright sunlight. Since TCASII is now required, I feel that the display should be readable under all normal conditions of cockpit lighting. This will prevent confusion during critical phases of flight. Feel free to call me if you need more information. Callback conversation with reporter revealed the following information: the reporter stated the collins personnel attempted to correct the problem. Collins stated the radar display was designed and intended for WX avoidance usually associated with embedded thunderstorms and at night when the cockpit would normally be dark as compared with a bright sunny day. A bright sunny day is when the TCASII is most helpful to alert the pilots in see and be seen sits negotiating airspace with VFR GA. Most flying is in daytime and the WX is predominantly bright and sunny. These are reasons the scope virtually blank with the TCASII saying 'traffic,' 'traffic' can be so frustrating to the pilot who is wondering where the traffic is. Furthermore, the passenger who sits almost with the pilots in the jetstream are hearing this imperative alarming voice saying traffic and the pilots have no more idea than the passenger where the traffic is. The reporter stated this airline also operates the saab which has a TCASII liquid emitting display that is actually part of the instantaneous vertical speed indicator and is not obliterated by sunlight. The reporter stated if the law is the TCASII must be installed it seems it should be usable especially when it is most needed. In the sunlight the radar scope looks like it is turned off. When the pilots need the information like around airports a pilot cupping his hands and leaning over the scope is impractical. It seems when the TCASII was installed the scope gain lost some intensity capability. The reporter has discovered a technique that by going to map mode and turning the gain to maximum and the antenna tilt down the screen becomes white except where a TCASII target is there is a black spot. This is not company procedure but helps.

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Original NASA ASRS Text

Title: THE RPTR IS UNABLE TO SEE TCASII INFO DISPLAYED ON THE RADAR SCOPE DURING BRIGHT SUNLIGHT.

Narrative: I AM WRITING TO NOTE PROBS WITH TCASII DISPLAYS. MY COMPANY HAS INSTALLED TCASII IN ALL OF OUR J31 ACFT TO COMPLY WITH RECENT TCASII REQUIREMENTS. THE TCASII INFO IS DISPLAYED ON A COLLINS WXR-270 RADAR SCREEN. I HAVE HAD SEVERAL PROBS WITH RECEIVING TA'S FROM TCASII AND BEING UNABLE TO DETERMINE THE POS OF THE TFC BECAUSE THE SCREEN WAS UNREADABLE WITH DIRECT SUNLIGHT ON THE SCREEN OR BRIGHT SUNLIGHT IN THE COCKPIT. I SPOKE WITH OUR MAINT DEPT AND THEY ADVISED ME THAT WXR-270 RADAR SCREEN WAS DESIGNED FOR VIEWING DURING OVCST DAYS OR AT NIGHT WHEN PLTS WOULD BE USING IT TO AVOID WX. DURING BRIGHT SUNNY DAYS, YOU MUST CUP YOUR HANDS OVER THE SCREEN TO SEE THE TCASII DISPLAY. I HAVE HAD SEVERAL INCIDENTS WHERE WE GOT A 'TA' BUT WERE UNABLE TO DETERMINE THE POS OF THE TFC BECAUSE OF THIS PROB. TODAY, I WAS AT 400 FT AGL WHEN I EXPERIENCED THIS PROB ON THE TKOF. I WOULD LIKE TO SUGGEST THAT THE TCASII INFO BE DISPLAYED ON A HIGHER QUALITY SCREEN OR ON A MORE RELIABLE SOURCE THAT IS NOT AFFECTED BY BRIGHT SUNLIGHT. SINCE TCASII IS NOW REQUIRED, I FEEL THAT THE DISPLAY SHOULD BE READABLE UNDER ALL NORMAL CONDITIONS OF COCKPIT LIGHTING. THIS WILL PREVENT CONFUSION DURING CRITICAL PHASES OF FLT. FEEL FREE TO CALL ME IF YOU NEED MORE INFO. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE COLLINS PERSONNEL ATTEMPTED TO CORRECT THE PROB. COLLINS STATED THE RADAR DISPLAY WAS DESIGNED AND INTENDED FOR WX AVOIDANCE USUALLY ASSOCIATED WITH EMBEDDED TSTMS AND AT NIGHT WHEN THE COCKPIT WOULD NORMALLY BE DARK AS COMPARED WITH A BRIGHT SUNNY DAY. A BRIGHT SUNNY DAY IS WHEN THE TCASII IS MOST HELPFUL TO ALERT THE PLTS IN SEE AND BE SEEN SITS NEGOTIATING AIRSPACE WITH VFR GA. MOST FLYING IS IN DAYTIME AND THE WX IS PREDOMINANTLY BRIGHT AND SUNNY. THESE ARE REASONS THE SCOPE VIRTUALLY BLANK WITH THE TCASII SAYING 'TFC,' 'TFC' CAN BE SO FRUSTRATING TO THE PLT WHO IS WONDERING WHERE THE TFC IS. FURTHERMORE, THE PAX WHO SITS ALMOST WITH THE PLTS IN THE JETSTREAM ARE HEARING THIS IMPERATIVE ALARMING VOICE SAYING TFC AND THE PLTS HAVE NO MORE IDEA THAN THE PAX WHERE THE TFC IS. THE RPTR STATED THIS AIRLINE ALSO OPERATES THE SAAB WHICH HAS A TCASII LIQUID EMITTING DISPLAY THAT IS ACTUALLY PART OF THE INSTANTANEOUS VERT SPD INDICATOR AND IS NOT OBLITERATED BY SUNLIGHT. THE RPTR STATED IF THE LAW IS THE TCASII MUST BE INSTALLED IT SEEMS IT SHOULD BE USABLE ESPECIALLY WHEN IT IS MOST NEEDED. IN THE SUNLIGHT THE RADAR SCOPE LOOKS LIKE IT IS TURNED OFF. WHEN THE PLTS NEED THE INFO LIKE AROUND ARPTS A PLT CUPPING HIS HANDS AND LEANING OVER THE SCOPE IS IMPRACTICAL. IT SEEMS WHEN THE TCASII WAS INSTALLED THE SCOPE GAIN LOST SOME INTENSITY CAPABILITY. THE RPTR HAS DISCOVERED A TECHNIQUE THAT BY GOING TO MAP MODE AND TURNING THE GAIN TO MAX AND THE ANTENNA TILT DOWN THE SCREEN BECOMES WHITE EXCEPT WHERE A TCASII TARGET IS THERE IS A BLACK SPOT. THIS IS NOT COMPANY PROC BUT HELPS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.