Narrative:

On approach; our landing gear did not extend when we moved the handle to the down position. I heard no hydraulic pump operation; and I did not feel the movement that normally accompanies gear operation. I chose to overfly the field for a visual inspection; and the tower informed us that the main gear were hanging down from the wells; but were not fully extended; and that the nose gear appeared to be completely retracted. I attempted a recycle of the switch; which did nothing. I then attempted a second recycle; which resulted in the gear pump activating; and the gear retracting fully; when I moved the handle to the up position. Moving the handle to the down position activated the pump again; and this time the gear extended fully and illuminated the green light indicating that the landing gear was down and locked. We chose to overfly the field again; and the tower reported that the gear appeared down; so we decided to land. The tower controller offered the assistance of a rescue crew; which I accepted; though I did not formally declare an emergency. I briefed my student on what to do in the event the gear collapsed on landing; in accordance with the checklist for the airplane; and we made a normal landing. After landing; I inspected the landing gear; and found it normal; with no visible defects. I could see that the mechanical down locks were in place; so I decided that it was safe to fly the aircraft back to its home base so long as the gear was left in the down position. That flight was uneventful. After the flight; I realized that I should have chosen to have the airplane inspected before flying it back. While the landing gear looked normal to the best of my knowledge; I am not a mechanic; and I don't have the requisite knowledge to make such a determination competently. Considering I had also experienced retraction problems in the same aircraft on a previous flight; I now realize that I should not have flown the airplane at all that day; as it was not in an airworthy condition. I believe I handled the in flight situation correctly; but my decision making on the ground was lacking; and I will be sure to take any mechanical defects more seriously in the future; especially those involving such a critical system as the landing gear. During my flight training; I had always been in an environment where proper maintenance was taken very seriously; to the point where I believe I became complacent about the ensuring the airworthiness of the aircraft I flew. I now realize that such attention to detail is not the norm; and that I must be far more vigilant; and intend to pass that wisdom on to my students.

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Original NASA ASRS Text

Title: C172RG instructor and student report failure of the landing gear to extend during approach. The gear switch was recycled twice before the landing gear extended normally. The reporters inspect the gear on the ground and elected to fly back to base with the gear extended; which is later questioned.

Narrative: On approach; our landing gear did not extend when we moved the handle to the down position. I heard no hydraulic pump operation; and I did not feel the movement that normally accompanies gear operation. I chose to overfly the field for a visual inspection; and the Tower informed us that the main gear were hanging down from the wells; but were not fully extended; and that the nose gear appeared to be completely retracted. I attempted a recycle of the switch; which did nothing. I then attempted a second recycle; which resulted in the gear pump activating; and the gear retracting fully; when I moved the handle to the up position. Moving the handle to the down position activated the pump again; and this time the gear extended fully and illuminated the green light indicating that the landing gear was down and locked. We chose to overfly the field again; and the Tower reported that the gear appeared down; so we decided to land. The Tower Controller offered the assistance of a rescue crew; which I accepted; though I did not formally declare an emergency. I briefed my student on what to do in the event the gear collapsed on landing; in accordance with the checklist for the airplane; and we made a normal landing. After landing; I inspected the landing gear; and found it normal; with no visible defects. I could see that the mechanical down locks were in place; so I decided that it was safe to fly the aircraft back to its home base so long as the gear was left in the down position. That flight was uneventful. After the flight; I realized that I should have chosen to have the airplane inspected before flying it back. While the landing gear looked normal to the best of my knowledge; I am not a mechanic; and I don't have the requisite knowledge to make such a determination competently. Considering I had also experienced retraction problems in the same aircraft on a previous flight; I now realize that I should not have flown the airplane at all that day; as it was not in an airworthy condition. I believe I handled the in flight situation correctly; but my decision making on the ground was lacking; and I will be sure to take any mechanical defects more seriously in the future; especially those involving such a critical system as the landing gear. During my flight training; I had always been in an environment where proper maintenance was taken very seriously; to the point where I believe I became complacent about the ensuring the airworthiness of the aircraft I flew. I now realize that such attention to detail is not the norm; and that I must be far more vigilant; and intend to pass that wisdom on to my students.

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.