HS125 captain experiences unreliable airspeed indication climbing through 3;500 ft resulting in an o...

Narrative:

Normal takeoff and initial climb through 3;500 ft captain's airspeed indicator made a 30 knot jump to increased airspeed then back to normal (approximately 230 KTS). A slight wobble on altimeter as well but settled down through 5;000 ft. At level off of 8;500 MSL airspeed on captain's side remained at 238 KTS; while co-pilot's indication was increasing through 250 KTS to approximately 290 KTS. Made several power adjustments to trend airspeed/power settings; and confirmed with captain's side air data computer analog information on nz 2000 that IAS was 40 KTS faster than indicated speed displayed on captain's airspeed. Remaining VFR flight conducted using co-pilot's information and display information from FMS; idc read out. Normal landing with no issues on operation to ramp parking. Upon inspection of captain's pitot tube a 'thumb nail size' piece of carcass stuck in and around entrance of pitot tube area. Small bird possible; however no other sign of bird impact noticed. Maintenance removed pitot tube; cleaned [it]; and re-installed. Aircraft is scheduled for complete pitot static; rvsm re-cert and aircraft will not operate in rvsm airspace until all required inspections of system are completed.

Original NASA ASRS Text

Title: HS125 Captain experiences unreliable airspeed indication climbing through 3;500 FT resulting in an overspeed upon leveling at 8;500 FT. Post flight reveals that a small bird may have impacted the Captain's pitot tube.

Narrative: Normal takeoff and initial climb through 3;500 FT Captain's airspeed indicator made a 30 knot jump to increased airspeed then back to normal (approximately 230 KTS). A slight wobble on altimeter as well but settled down through 5;000 FT. At level off of 8;500 MSL airspeed on Captain's side remained at 238 KTS; while Co-pilot's indication was increasing through 250 KTS to approximately 290 KTS. Made several power adjustments to trend airspeed/power settings; and confirmed with Captain's side ADC analog information on NZ 2000 that IAS was 40 KTS faster than indicated speed displayed on Captain's airspeed. Remaining VFR flight conducted using Co-pilot's information and display information from FMS; IDC read out. Normal landing with no issues on operation to ramp parking. Upon inspection of Captain's Pitot tube a 'thumb nail size' piece of carcass stuck in and around entrance of pitot tube area. Small bird possible; however no other sign of bird impact noticed. Maintenance removed pitot tube; cleaned [it]; and re-installed. Aircraft is scheduled for complete Pitot Static; RVSM re-cert and aircraft will not operate in RVSM airspace until all required inspections of system are completed.

Data retrieved from NASA's ASRS site as of July 2013 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	1099087
Time
Date	201307
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
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	VFR
Component
Aircraft Component	Pitot-Static System
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 39 Flight Crew Total 11000 Flight Crew Type 4500
Events
Anomaly	Aircraft Equipment Problem Critical Inflight Event / Encounter Bird / Animal

HS125 captain experiences unreliable airspeed indication climbing through 3;500 ft resulting in an overspeed upon leveling at 8;500 ft. Post flight reveals that a small bird may have impacted the captain's pitot tube.