Narrative:

After rotation, the elevator became almost unresponsive. I could get come movement by pulling or pushing with both hands exerting 50-80 pounds of pressure. Performed some troubleshooting, ie, circuit breakers in, and checking that hydraulic pressure and quantity were ok. Operations manual no help. Called maintenance who had no ideas. I declared an emergency and returned via ILS runway 9R. Stabilizer trim worked fine and used that for pitch control during landing. Landed with flaps 25 degrees and no problem. There were no faults indicated. Takeoff configuration check prior to takeoff, normal. Callback conversation with reporter revealed the following information: the aircraft was removed from service and given a maintenance inspection. Nothing was found. The aircraft was then scheduled for flight test. On the test flight, the same problem reoccurred. The flight test crew declared an emergency and got the aircraft back on the ground. After 2 days of maintenance troubleshooting, maintenance was still unable to duplicate the problem. Maintenance then replaced both the #1 and #2 elevator hydraulic control units and actuators. The aircraft was then scheduled for a second flight test. The problem did not reoccur. The reporter does not know what problems were found with the hydraulic actuators or control units. The captain has 11 yrs experience on the aircraft and is not aware of a similar incident. The flight control check before takeoff was normal.

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Original NASA ASRS Text

Title: F100 CREW, AFTER TKOF, FOUND THEY HAD ALMOST NO ELEVATOR PITCH CTL OF THE ACFT IN CE90 CLASS B.

Narrative: AFTER ROTATION, THE ELEVATOR BECAME ALMOST UNRESPONSIVE. I COULD GET COME MOVEMENT BY PULLING OR PUSHING WITH BOTH HANDS EXERTING 50-80 LBS OF PRESSURE. PERFORMED SOME TROUBLESHOOTING, IE, CIRCUIT BREAKERS IN, AND CHKING THAT HYD PRESSURE AND QUANTITY WERE OK. OPS MANUAL NO HELP. CALLED MAINT WHO HAD NO IDEAS. I DECLARED AN EMER AND RETURNED VIA ILS RWY 9R. STABILIZER TRIM WORKED FINE AND USED THAT FOR PITCH CTL DURING LNDG. LANDED WITH FLAPS 25 DEGS AND NO PROB. THERE WERE NO FAULTS INDICATED. TKOF CONFIGURATION CHK PRIOR TO TKOF, NORMAL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE ACFT WAS REMOVED FROM SVC AND GIVEN A MAINT INSPECTION. NOTHING WAS FOUND. THE ACFT WAS THEN SCHEDULED FOR FLT TEST. ON THE TEST FLT, THE SAME PROB REOCCURRED. THE FLT TEST CREW DECLARED AN EMER AND GOT THE ACFT BACK ON THE GND. AFTER 2 DAYS OF MAINT TROUBLESHOOTING, MAINT WAS STILL UNABLE TO DUPLICATE THE PROB. MAINT THEN REPLACED BOTH THE #1 AND #2 ELEVATOR HYD CTL UNITS AND ACTUATORS. THE ACFT WAS THEN SCHEDULED FOR A SECOND FLT TEST. THE PROB DID NOT REOCCUR. THE RPTR DOES NOT KNOW WHAT PROBS WERE FOUND WITH THE HYD ACTUATORS OR CTL UNITS. THE CAPT HAS 11 YRS EXPERIENCE ON THE ACFT AND IS NOT AWARE OF A SIMILAR INCIDENT. THE FLT CTL CHK BEFORE TKOF WAS NORMAL.

Data retrieved from NASA's ASRS site as of July 2007 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.