Narrative:

After being asked to extend a downwind at 3;000 by ATC for an approach to runway xx in ZZZ; I turned base and began a rapid descent around 5 nm from the field. Upon turning final; I leveled off to reduce airspeed before beginning my prelanding checklist. I lowered the landing gear lever and 3 to 5 seconds later; I received a three green; gear down indication. Immediately after; however; I lost all electrical systems; including my gear indication lights. Because I was cleared for landing; and this had become an emergency; I made the decision to land as quickly and safely as possible. I completed my pre-landing checklist and looked to the tower for a light gun signal; but there wasn't one. I also reset the master and avionics switches to no avail. I still believed that my gear had lowered properly. Upon touching down; I quickly realized that my gear had not lowered properly when my wing step struck the ground. I maintained the center of the runway until the plane came to a stop; after which; I exited the plane promptly and attempted to call tower.I believe that a faulty gear pump caused the gear not to descend properly and the electrical system to fail. At this point; I do not know the cause of the false gear-down indication. To prevent the recurrence of this situation; I believe that in the event of an electrical failure; a pilot should always make use of the emergency gear actuator handle to ensure that the gear is down on final approach; no matter if the gear is believed to have descended properly.

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Original NASA ASRS Text

Title: PA-28R pilot reported that during landing the landing gear did not lower properly.

Narrative: After being asked to extend a downwind at 3;000 by ATC for an approach to runway XX in ZZZ; I turned base and began a rapid descent around 5 nm from the field. Upon turning final; I leveled off to reduce airspeed before beginning my prelanding checklist. I lowered the landing gear lever and 3 to 5 seconds later; I received a three green; gear down indication. Immediately after; however; I lost all electrical systems; including my gear indication lights. Because I was cleared for landing; and this had become an emergency; I made the decision to land as quickly and safely as possible. I completed my pre-landing checklist and looked to the tower for a light gun signal; but there wasn't one. I also reset the master and avionics switches to no avail. I still believed that my gear had lowered properly. Upon touching down; I quickly realized that my gear had not lowered properly when my wing step struck the ground. I maintained the center of the runway until the plane came to a stop; after which; I exited the plane promptly and attempted to call Tower.I believe that a faulty gear pump caused the gear not to descend properly and the electrical system to fail. At this point; I do not know the cause of the false gear-down indication. To prevent the recurrence of this situation; I believe that in the event of an electrical failure; a pilot should ALWAYS make use of the emergency gear actuator handle to ensure that the gear is down on final approach; no matter if the gear is believed to have descended properly.

Data retrieved from NASA's ASRS site 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.