SF340 flight crew suffers hydraulic system anomalies immediately after takeoff. Returned to departur...

Attributes
ACN	816002
Time
Date	200812
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	SF 340B
Operating Under FAR Part	Part 121
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial
ASRS Report	816002
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : master warning other flight crewa
Resolutory Action	flight crew : declared emergency flight crew : landed in emergency condition other
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Everything was normal until just after takeoff when I called for 'gear up; heading; indicated airspeed (IAS).' the captain selected the gear up; heading and IAS modes. We both then noticed that the green down-lock lights had extinguished but the orange gear handle light was still illuminated with the hydraulic pump not running. Immediately thereafter; we received a master caution with a hydraulic look-down light. The captain; as pilot not flying; completed the memory items for the hydraulic look-down light and proceeded to the appropriate checklist in the emergency/non-normal checklist. The captain coordinated with dispatch and ATC while I flew the plane and backed him up on the radios. Upon turning around to return to ZZZ; we agreed that in the interest of safety; we should declare an emergency in consideration of our limited amount of hydraulic pressure available. The captain briefed the flight attendant on the situation and we received vectors back to ZZZ for a visual approach. We had previously computed the appropriate adjustments to our landing data and performance for a zero-flap landing; which we agreed that was the safest approach to make in our situation. A routine landing was made; after which we turned off the runway and received a tow back to the gate; per the checklist.

Original NASA ASRS Text

Title: SF340 flight crew suffers hydraulic system anomalies immediately after takeoff. Returned to departure airport under emergency conditions and performed zero flap landing.

Narrative: Everything was normal until just after takeoff when I called for 'gear up; heading; indicated airspeed (IAS).' The Captain selected the gear up; heading and IAS modes. We both then noticed that the green down-lock lights had extinguished but the orange gear handle light was still illuminated with the hydraulic pump not running. Immediately thereafter; we received a master caution with a hydraulic look-down light. The Captain; as Pilot Not Flying; completed the memory items for the hydraulic look-down light and proceeded to the appropriate checklist in the Emergency/Non-Normal checklist. The Captain coordinated with Dispatch and ATC while I flew the plane and backed him up on the radios. Upon turning around to return to ZZZ; we agreed that in the interest of safety; we should declare an emergency in consideration of our limited amount of hydraulic pressure available. The Captain briefed the Flight Attendant on the situation and we received vectors back to ZZZ for a visual approach. We had previously computed the appropriate adjustments to our landing data and performance for a zero-flap landing; which we agreed that was the safest approach to make in our situation. A routine landing was made; after which we turned off the runway and received a tow back to the gate; per the checklist.

Data retrieved from NASA's ASRS site as of May 2009 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.