A C-550 climbed through their cleared flight level and experienced a TCAS RA when they failed to set...

Attributes
ACN	915820
Time
Date	201010
Local Time Of Day	0601-1200
Place
Locale Reference	ZAU.ARTCC
State Reference	IL
Environment
Light	Dawn
Aircraft 1
Make Model Name	Citation II S2/Bravo (C550)
Operating Under FAR Part	Part 135
Flight Phase	Climb
Route In Use	Direct
Flight Plan	IFR
Component
Aircraft Component	Altimeter
Person 1
Function	Captain
Qualification	Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 100 Flight Crew Total 4500 Flight Crew Type 4200
Events
Anomaly	Deviation - Altitude Overshoot Deviation - Procedural Clearance Deviation - Procedural FAR Inflight Event / Encounter Weather / Turbulence
Miss Distance	Horizontal 2 Vertical 800

Narrative:

Climbing to FL190 at 2;200 ft per minute to avoid moderate turbulence. Altimeter setting of 29.10 at 17;800 from the departure airport. Received an RA to adjust vertical speed. During the process of adjusting vertical speed as quickly as possible and watching for the traffic we changed the altimeter setting to 29.92. By the time we adjusted for the large pressure change we were at 19;200. Then we took action to get back to assigned altitude as quickly and safely as possible. I believe the turbulence; the TA; the abnormal pressure change; and watching for the other aircraft were all factors. To prevent a recurrence I believe that when the altimeter setting is that different from standard maybe a policy or precaution to change the setting earlier especially with a level off within a thousand feet of FL180.

Original NASA ASRS Text

Title: A C-550 climbed through their cleared Flight Level and experienced a TCAS RA when they failed to set QNH passing FL180. A very low altimeter setting below FL180 contributed to the error.

Narrative: Climbing to FL190 at 2;200 FT per minute to avoid moderate turbulence. Altimeter setting of 29.10 at 17;800 from the departure airport. Received an RA to adjust vertical speed. During the process of adjusting vertical speed as quickly as possible and watching for the traffic we changed the altimeter setting to 29.92. By the time we adjusted for the large pressure change we were at 19;200. Then we took action to get back to assigned altitude as quickly and safely as possible. I believe the turbulence; the TA; the abnormal pressure change; and watching for the other aircraft were all factors. To prevent a recurrence I believe that when the altimeter setting is that different from standard maybe a policy or precaution to change the setting earlier especially with a level off within a thousand feet of FL180.

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.

A C-550 climbed through their cleared flight level and experienced a TCAS RA when they failed to set qnh passing FL180. A very low altimeter setting below FL180 contributed to the error.