Corporate flight crew of hawker 850 xp at FL360 experienced a TCAS RA requiring descent; reporter in...

Attributes
ACN	843226
Time
Date	200907
Local Time Of Day	0601-1200
Place
Locale Reference	ZOB.ARTCC
State Reference	OH
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Make Model Name	BAe 125 Series 800
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	IFR
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Flight Engineer Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 14000 Flight Crew Type 2500
Person 2
Function	First Officer Pilot Flying
Qualification	Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 7300 Flight Crew Type 300
Events
Anomaly	Conflict Airborne Conflict Deviation - Altitude Excursion From Assigned Altitude Inflight Event / Encounter Weather / Turbulence
Miss Distance	Horizontal 20000 Vertical 700

Narrative:

Flying at FL350 toward hoxie on a heading about 30 miles west of dkk on the north side of lake erie. We were still in the thin tops and saw one cell at our 10 o'clock and if we went on a heading of twenty right we would split two cells with one at two o'clock. Tops were shown our xm as about 26;000. Light occasionally moderate turbulence and no precipitation or any hail. We asked and were granted FL360 to try and get on top. We were level at FL360 for about a minute and still not quite on top. I was looking down doing paperwork when I heard the TCAS 'descend; descend' as I felt the aircraft experience an updraft. As I looked up flying pilot had reduced power and began a descent in compliance with the TCAS RA. I believe I saw a maximum altitude of 36;250. I announced to ATC that we were in a TCAS descent. Not sure if ATC got it as there was a lot of static on the frequency at that time. When we began our climb back to FL360 I believe we bottomed out at about 35;000. This was due in part to what I believe was the down draft which followed the updraft we had just experienced. After leveling back at FL360 I told ATC that we were back and level at FL360. Before we left the frequency I asked if he had gotten my tacs descent alert and he said yes he had.

Original NASA ASRS Text

Title: Corporate flight crew of Hawker 850 XP at FL360 experienced a TCAS RA requiring descent; reporter indicating updraft resulted in a climb to 36;250; which likely caused the TCAS event.

Narrative: Flying at FL350 toward Hoxie on a heading about 30 miles West of DKK on the north side of Lake Erie. We were still in the thin tops and saw one cell at our 10 o'clock and if we went on a heading of twenty right we would split two cells with one at two o'clock. Tops were shown our XM as about 26;000. Light occasionally moderate turbulence and no precipitation or any hail. We asked and were granted FL360 to try and get on top. We were level at FL360 for about a minute and still not quite on top. I was looking down doing paperwork when I heard the TCAS 'descend; descend' as I felt the aircraft experience an updraft. As I looked up flying pilot had reduced power and began a descent in compliance with the TCAS RA. I believe I saw a maximum altitude of 36;250. I announced to ATC that we were in a TCAS descent. Not sure if ATC got it as there was a lot of static on the frequency at that time. When we began our climb back to FL360 I believe we bottomed out at about 35;000. This was due in part to what I believe was the down draft which followed the updraft we had just experienced. After leveling back at FL360 I told ATC that we were back and level at FL360. Before we left the frequency I asked if he had gotten my TACS descent alert and he said yes he had.

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.

Corporate flight crew of hawker 850 xp at FL360 experienced a TCAS RA requiring descent; reporter indicating updraft resulted in a climb to 36;250; which likely caused the TCAS event.