Narrative:

Approximately 100 NM out; the first officer pointed out that the hydraulic system had low pressure (1250 psi in a 1475-1750 psi system) and pump pressure was cycling frequently when a hydraulic component was used. The pressure in the system slowly decreased. At 50 NM out we were reading 1150 psi. I had the first office open the jet doors and the landing gear was lowered with no problem. We performed the emergency hydraulic failure checklist. It was not an emergency; but that was the only item that even came close to what we were seeing. I knew we would need better than 900 psi to keep the priority valve from taking the system to run the varicam only. Fluid levels were all good. Also; the emergency hydraulic system was at normal pressure and fully operational. However; company policy and the flight manual for hydraulic malfunctions requires that we stop on the runway and pin the gear; as well as have the aircraft towed. I had the first officer contact approach to see if any IFR traffic was inbound and to have them advise the tower we would need time on the runway to pin the gear (they had only one departure prior to arrival). He clearly stated that this was not an emergency. He told approach that we had lowered the gear and it was down. We did not ask for any special handling; nor did we request any priority. I felt that this was not an emergency; but an inconvenience. Just prior to handing off to tower; approach told us that the equipment was being rolled out. I think this was the first sign that a possible miscommunication between approach and tower had occurred. Upon initial contact with tower we were immediately cleared for a low approach. We had not asked for one. We made a high overhead initial for runway 29 at 2;000 ft AGL. The tower told us the gear appeared to be down. An odd call I thought. We both expressed surprised by the statement but continued sterile cockpit. Shortly thereafter we were cleared to land. A normal landing was made. I decided that the hydraulic pressure was sufficient to turn off at mid-field and shut-down. The first officer pinned the gear and had the aircraft towed to our company maintenance hanger. At the hanger I was advised that the tower had called and was angry about us not having declared an emergency and/or asking for priority. They never contacted me directly and I never talked to them.

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Original NASA ASRS Text

Title: A P2V experienced a low hydraulic system pressure; the Captain subsequently configured the aircraft early for landing. After advising ATC about the anomaly but not declaring an emergency ATC treated the flight as an emergency but was upset that none was declared.

Narrative: Approximately 100 NM out; the First Officer pointed out that the hydraulic system had low pressure (1250 PSI in a 1475-1750 PSI system) and pump pressure was cycling frequently when a hydraulic component was used. The pressure in the system slowly decreased. At 50 NM out we were reading 1150 PSI. I had the First Office open the jet doors and the landing gear was lowered with no problem. We performed the emergency hydraulic failure checklist. It was not an emergency; but that was the only item that even came close to what we were seeing. I knew we would need better than 900 PSI to keep the priority valve from taking the system to run the VARICAM only. Fluid levels were all good. Also; the emergency hydraulic system was at normal pressure and fully operational. However; Company policy and the flight manual for hydraulic malfunctions requires that we stop on the runway and pin the gear; as well as have the aircraft towed. I had the First Officer contact Approach to see if any IFR traffic was inbound and to have them advise the Tower we would need time on the runway to pin the gear (they had only one departure prior to arrival). He clearly stated that this was not an emergency. He told Approach that we had lowered the gear and it was down. We did not ask for any special handling; nor did we request any priority. I felt that this was not an emergency; but an inconvenience. Just prior to handing off to Tower; Approach told us that the equipment was being rolled out. I think this was the first sign that a possible miscommunication between Approach and Tower had occurred. Upon initial contact with Tower we were immediately cleared for a low approach. We had not asked for one. We made a high overhead initial for Runway 29 at 2;000 FT AGL. The Tower told us the gear appeared to be down. An odd call I thought. We both expressed surprised by the statement but continued sterile cockpit. Shortly thereafter we were cleared to land. A normal landing was made. I decided that the hydraulic pressure was sufficient to turn off at mid-field and shut-down. The First Officer pinned the gear and had the aircraft towed to our Company maintenance hanger. At the hanger I was advised that the Tower had called and was angry about us not having declared an emergency and/or asking for priority. They never contacted me directly and I never talked to them.

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.