 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Emb-505 crew reported an incorrect TCAS RA solution generated by the equipment.
| Attributes | |
| ACN | 1531646 |
| Time | |
| Date | 201804 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | PHX.Airport |
| State Reference | AZ |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Make Model Name | EMB-505 / Phenom 300 |
| Flight Phase | Cruise |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | TCAS Software |
| Person 1 | |
| Function | Captain Pilot Not Flying |
| Person 2 | |
| Function | First Officer |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Events | |
| Anomaly | Aircraft Equipment Problem Less Severe Conflict Airborne Conflict |
Narrative:
Incorrect TCAS (traffic collision alert system) RA (resolution advisory) response! By the TCAS; not crew!emb-505 was about 10-15 NM southwest of phx. We were at 5;000 feet MSL on a 280 degree heading. Sky harbor approach stated their intent to bring us to the south side of phx; then vector us over phx for an eventual visual to sdl. ATC began calling traffic to us: 2 targets at 4;500 feet MSL. They were 5-7 miles apart. Target 1 was the real issue. Both were showing on TCAS and we could see target 1. As we got within proximity of target 1; the TCAS commanded an RA. But it commanded a descent! It did it twice before it changed its mind and commanded a climb. We climbed to 5;300 feet MSL. ATC held us there for a couple of minutes then reassigned us previous altitude. There was no traffic above us to offer conflict. This seemingly erroneous command is very troubling. If the algorithms that govern this system aren't correct; that is not good.
Original NASA ASRS Text
Title: EMB-505 crew reported an incorrect TCAS RA solution generated by the equipment.
Narrative: Incorrect TCAS (Traffic Collision Alert System) RA (Resolution Advisory) response! By the TCAS; not crew!EMB-505 was about 10-15 NM southwest of PHX. We were at 5;000 feet MSL on a 280 degree heading. Sky Harbor Approach stated their intent to bring us to the south side of PHX; then vector us over PHX for an eventual visual to SDL. ATC began calling traffic to us: 2 targets at 4;500 feet MSL. They were 5-7 miles apart. Target 1 was the real issue. Both were showing on TCAS and we could see target 1. As we got within proximity of target 1; the TCAS commanded an RA. But it commanded a descent! It did it twice before it changed its mind and commanded a climb. We climbed to 5;300 feet MSL. ATC held us there for a couple of minutes then reassigned us previous altitude. There was no traffic above us to offer conflict. This seemingly erroneous command is very troubling. If the algorithms that govern this system aren't correct; that is not good.
Data retrieved from NASA's ASRS site 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.