Narrative:

Practice flight for new partner transitioning into this aircraft. After practice approachs, practicing touch and goes. On third touch and go abeam tower, PF selected 'gear down' and states had '3 green.' on short final heard a noise (like electrical motor) and tower called that our landing gear was up. Executed go around and verified that the gear handle was indeed down but no visible green or red indicators. On climb out, safety pilot activated gear handle up and down several times with no result. Advised tower and proceeded to practice area to manually extend gear. Followed poh checklist for manual gear extension but, halfway down 60 of 114 cranks manual gear handle jammed and wouldn't extend further. Attempted air maneuvers to free gear to no avail. A 'post-it' note in the emergency section of the poh which had been there for yrs detailed an alternate method of extending the gear. On second attempt this worked. Advised approach and tower and flew by tower for visual which revealed gear down in addition to '3 green' and floor mounted gear alignment indicator. ATC elected to deploy fire equipment. Landed safely. Will advise the aircraft manufacturer of this incident, particularly as poh emergency gear extension procedure didn't work, but a hand-written anonymous procedure did. An addendum to M20J poh may be warranted. Callback conversation with reporter revealed the following information: reporter states that he called mooney to let them know about the problem and the nonstandard procedures which worked. Essentially one does everything backwards. Comply with the procedures but accomplish them in reverse order from what is listed. Then activate the electric motor again and it does the job. When mechanic checked the problem he found a bent actuator rod. This was replaced and there has been no problem since. The question is did the procedure cause the bent actuator or did the bent actuator cause the problem? No way to really know the answer. Reporter again spoke to mooney personnel who suggested checking one other area, the electric motor itself. In the wound coil there was a flat spot and the motor would stop at that point. That is apparently what had failed the first time when the previous owner discovered the alternate technique. Reporter tried to purchase a new motor and they are no longer manufactured so he replaced the entire gear system at great expense. He and his partners now have a new procedure of their own. They do not look for a green light. On gear extension they hear it (the motor), they feel it (thump), they see it (green light). That has become their standard procedure.

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Original NASA ASRS Text

Title: MOONEY 20J HAS GEAR EXTENSION PROB ON APCH TO LNDG. USE OF THE POH GAVE NEGATIVE RESULTS. A POST-IT STUCK TO THE POH OFFERED AN ALTERNATE METHOD WHICH WORKED.

Narrative: PRACTICE FLT FOR NEW PARTNER TRANSITIONING INTO THIS ACFT. AFTER PRACTICE APCHS, PRACTICING TOUCH AND GOES. ON THIRD TOUCH AND GO ABEAM TWR, PF SELECTED 'GEAR DOWN' AND STATES HAD '3 GREEN.' ON SHORT FINAL HEARD A NOISE (LIKE ELECTRICAL MOTOR) AND TWR CALLED THAT OUR LNDG GEAR WAS UP. EXECUTED GAR AND VERIFIED THAT THE GEAR HANDLE WAS INDEED DOWN BUT NO VISIBLE GREEN OR RED INDICATORS. ON CLBOUT, SAFETY PLT ACTIVATED GEAR HANDLE UP AND DOWN SEVERAL TIMES WITH NO RESULT. ADVISED TWR AND PROCEEDED TO PRACTICE AREA TO MANUALLY EXTEND GEAR. FOLLOWED POH CHKLIST FOR MANUAL GEAR EXTENSION BUT, HALFWAY DOWN 60 OF 114 CRANKS MANUAL GEAR HANDLE JAMMED AND WOULDN'T EXTEND FURTHER. ATTEMPTED AIR MANEUVERS TO FREE GEAR TO NO AVAIL. A 'POST-IT' NOTE IN THE EMER SECTION OF THE POH WHICH HAD BEEN THERE FOR YRS DETAILED AN ALTERNATE METHOD OF EXTENDING THE GEAR. ON SECOND ATTEMPT THIS WORKED. ADVISED APCH AND TWR AND FLEW BY TWR FOR VISUAL WHICH REVEALED GEAR DOWN IN ADDITION TO '3 GREEN' AND FLOOR MOUNTED GEAR ALIGNMENT INDICATOR. ATC ELECTED TO DEPLOY FIRE EQUIP. LANDED SAFELY. WILL ADVISE THE ACFT MANUFACTURER OF THIS INCIDENT, PARTICULARLY AS POH EMER GEAR EXTENSION PROC DIDN'T WORK, BUT A HAND-WRITTEN ANONYMOUS PROC DID. AN ADDENDUM TO M20J POH MAY BE WARRANTED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT HE CALLED MOONEY TO LET THEM KNOW ABOUT THE PROB AND THE NONSTANDARD PROCS WHICH WORKED. ESSENTIALLY ONE DOES EVERYTHING BACKWARDS. COMPLY WITH THE PROCS BUT ACCOMPLISH THEM IN REVERSE ORDER FROM WHAT IS LISTED. THEN ACTIVATE THE ELECTRIC MOTOR AGAIN AND IT DOES THE JOB. WHEN MECH CHKED THE PROB HE FOUND A BENT ACTUATOR ROD. THIS WAS REPLACED AND THERE HAS BEEN NO PROB SINCE. THE QUESTION IS DID THE PROC CAUSE THE BENT ACTUATOR OR DID THE BENT ACTUATOR CAUSE THE PROB? NO WAY TO REALLY KNOW THE ANSWER. RPTR AGAIN SPOKE TO MOONEY PERSONNEL WHO SUGGESTED CHKING ONE OTHER AREA, THE ELECTRIC MOTOR ITSELF. IN THE WOUND COIL THERE WAS A FLAT SPOT AND THE MOTOR WOULD STOP AT THAT POINT. THAT IS APPARENTLY WHAT HAD FAILED THE FIRST TIME WHEN THE PREVIOUS OWNER DISCOVERED THE ALTERNATE TECHNIQUE. RPTR TRIED TO PURCHASE A NEW MOTOR AND THEY ARE NO LONGER MANUFACTURED SO HE REPLACED THE ENTIRE GEAR SYS AT GREAT EXPENSE. HE AND HIS PARTNERS NOW HAVE A NEW PROC OF THEIR OWN. THEY DO NOT LOOK FOR A GREEN LIGHT. ON GEAR EXTENSION THEY HEAR IT (THE MOTOR), THEY FEEL IT (THUMP), THEY SEE IT (GREEN LIGHT). THAT HAS BECOME THEIR STANDARD PROC.

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.