G200 experienced decreasing airspeed at FL430 due to turbulence and increasing OAT. A descent initia...

Attributes
ACN	918118
Time
Date	201011
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Gulfstream G200 (IAI 1126 Galaxy)
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 75 Flight Crew Total 6600 Flight Crew Type 600
Events
Anomaly	Conflict Airborne Conflict Deviation - Speed All Types Inflight Event / Encounter Weather / Turbulence
Miss Distance	Horizontal 6000 Vertical 1000

Narrative:

I received a TCAS RA as a result of an emergency descent which I initiated. We were initially level at FL430 when we began to experience occasional moderate turbulence and increasing outside air temperature. This caused significant airspeed deviations and eventual loss of airspeed to nearly stall speed. We attempted contact with air traffic control numerous times; but were unable to establish contact due to frequency congestion. When we eventually did contact ATC; we requested an immediate descent which I initiated simultaneously. At that time ATC directed an immediate right turn and declared an emergency. He also called out conflicting traffic which we were able to observe visually. We subsequently received a resolution advisory which I complied with by leveling the aircraft until clear of conflict. ATC then cleared us to FL400 and direct to our next flight planned fix. I contacted the ATC controller via telephone after landing per his instructions. He indicated that he would submit a loss of separation report.

Original NASA ASRS Text

Title: G200 experienced decreasing airspeed at FL430 due to turbulence and increasing OAT. A descent initiated prior to receiving clearance results in a TCAS RA.

Narrative: I received a TCAS RA as a result of an emergency descent which I initiated. We were initially level at FL430 when we began to experience occasional moderate turbulence and increasing outside air temperature. This caused significant airspeed deviations and eventual loss of airspeed to nearly stall speed. We attempted contact with Air Traffic Control numerous times; but were unable to establish contact due to frequency congestion. When we eventually did contact ATC; we requested an immediate descent which I initiated simultaneously. At that time ATC directed an immediate right turn and declared an emergency. He also called out conflicting traffic which we were able to observe visually. We subsequently received a Resolution Advisory which I complied with by leveling the aircraft until clear of conflict. ATC then cleared us to FL400 and direct to our next flight planned fix. I contacted the ATC Controller via telephone after landing per his instructions. He indicated that he would submit a loss of separation report.

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.