DHC8 captain experiences a TCAS RA shortly after takeoff with the intruder aircraft collocated with ...

Narrative:

On climb out; just a few feet past acceleration height; our TCAS started giving us erroneous RA's 'monitor vertical speed' followed by 'descend; descend' [and] a red square was displayed on top of our aircraft indicating that another airplane was on top of us. The TCAS gave us no proximate traffic call outs before this and no targets were displayed on it beforehand. All of a sudden a red square just appeared on top of our position. ATC said nothing of any other traffic being within our proximity and we could see no other traffic around us (VMC day) except for a 737 (which we had visual contact with) that had taken off before us and was about 10 miles to the southeast of us and about 1;000 ft above us. We leveled off our altitude and told ATC of our malfunctioning TCAS and said we needed to return. ATC gave us vectors for the visual approach and all the way to the point of touchdown that red square with '00' on top of it was showing up on our TCAS; with resolution advisories of 'descend; descend' aurally warning us until we landed.

Original NASA ASRS Text

Title: DHC8 Captain experiences a TCAS RA shortly after takeoff with the intruder aircraft collocated with zero altitude differential. The Captain elects to return to the departure airport with the TCAS annunciating 'descend descend' all the way to landing.

Narrative: On climb out; just a few feet past acceleration height; our TCAS started giving us erroneous RA's 'monitor vertical speed' followed by 'descend; descend' [and] a red square was displayed on top of our aircraft indicating that another airplane was on top of us. The TCAS gave us no proximate traffic call outs before this and no targets were displayed on it beforehand. All of a sudden a red square just appeared on top of our position. ATC said nothing of any other traffic being within our proximity and we could see no other traffic around us (VMC day) except for a 737 (which we had visual contact with) that had taken off before us and was about 10 miles to the SE of us and about 1;000 FT above us. We leveled off our altitude and told ATC of our malfunctioning TCAS and said we needed to return. ATC gave us vectors for the visual approach and all the way to the point of touchdown that red square with '00' on top of it was showing up on our TCAS; with resolution advisories of 'descend; descend' aurally warning us until we landed.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	967767
Time
Date	201108
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Dash 8-200
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	TCAS Equipment
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

DHC8 captain experiences a TCAS RA shortly after takeoff with the intruder aircraft collocated with zero altitude differential. The captain elects to return to the departure airport with the TCAS annunciating 'descend descend' all the way to landing.