B737-800 first officer reported airspeed; elevator feel differential; and eec anomalies. First offic...

Narrative:

On departure; noticed first officer airspeed indication erratic. Settled down; but was consistently 4-8 KTS lower than captain. Did IAS disagree checklist; referred to airspeed unreliable checklist. Completed checklist. Captain airspeed good; first officer airspeed -4 to -8 KTS; standby airspeed -50 KTS. Captain was pilot flying; we determined aircraft safe to continue; but watched all airspeed closely throughout flight. Approximately 45 minutes from landing noticed elevator feel differential light was on; which stayed on until touchdown. On start of descent; when throttles came back got both engine eec's reversion to alternate mode. Did eec alternate mode checklist. All engine parameters were normal; continued descent. As aircraft was leveling from 11;000 ft to 10;000 ft; captain airspeed indication dropped 50+ KTS. Throttles went to max; and nose pitched over. Captain disconnected throttles; we cross checked airspeed indications captain/first officer/pfd; and determined that first officer airspeed was most accurate. Captain transferred control of aircraft to me. Captain declared emergency and asked for airfield equipment. I continued approach and landing with autothrottles and autopilot off using my airspeed; pitch/throttle position; and aoa indications. Captain's airspeed indication came back close to first officer's indications. Throughout incident standby airspeed was much lower and unusable. Landing uneventful taxied to gate.

Original NASA ASRS Text

Title: B737-800 First Officer reported airspeed; elevator feel differential; and EEC anomalies. First Officer airspeed was deemed most reliable and flight continued to destination after declaring an emergency.

Narrative: On departure; noticed First Officer airspeed indication erratic. Settled down; but was consistently 4-8 KTS lower than Captain. Did IAS Disagree checklist; referred to Airspeed Unreliable checklist. Completed checklist. Captain airspeed good; First Officer airspeed -4 to -8 KTS; standby airspeed -50 KTS. Captain was pilot flying; we determined aircraft safe to continue; but watched all airspeed closely throughout flight. Approximately 45 minutes from landing noticed Elevator Feel Differential light was on; which stayed on until touchdown. On start of descent; when throttles came back got both engine EEC's reversion to Alternate mode. Did EEC Alternate Mode checklist. All engine parameters were normal; continued descent. As aircraft was leveling from 11;000 FT to 10;000 FT; Captain airspeed indication dropped 50+ KTS. Throttles went to max; and nose pitched over. Captain disconnected throttles; we cross checked airspeed indications Captain/First Officer/PFD; and determined that First Officer airspeed was most accurate. Captain transferred control of aircraft to me. Captain declared emergency and asked for airfield equipment. I continued approach and landing with autothrottles and autopilot off using my airspeed; pitch/throttle position; and AOA indications. Captain's airspeed indication came back close to First Officer's indications. Throughout incident standby airspeed was much lower and unusable. Landing uneventful taxied to gate.

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	1097906
Time
Date	201306
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Component
Aircraft Component	Air Data Computer
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical

B737-800 first officer reported airspeed; elevator feel differential; and eec anomalies. First officer airspeed was deemed most reliable and flight continued to destination after declaring an emergency.