October 16, 2021: Aircraft landed gear up due to loss of electrical system at University of Oklahoma Westheimer Airport (KOUN), Norman, Cleveland County, Oklahoma.
DatchCorr LLC
Date: 16-OCT-21
Time: 21:44:00Z
Regis#: N83615
Aircraft Make: PIPER
Aircraft Model: CHEROKEE SIX
Event Type: INCIDENT
Highest Injury: NONE
Aircraft Missing: No
Damage: UNKNOWN
Activity: PERSONAL
Flight Phase: LANDING (LDG)
Operation: 91
City: NORMAN
State: OKLAHOMA
The emergency gear extension system for a PA32 does not require any electricity. Therefore a loss of the electrical system WOULD NOT lead to a gear up landing. Pilot error would however.
ReplyDeleteWell yes and no. It does not have a manual hand pump option. If all electricity is lost for whatever reason, the only option is to hold the emergency gear lever down for 10 seconds and then side slip to try and dislodge the mains. But if the pilot is not successful in doing that with the time (or fuel) left to keep playing around, then yes, it should be considered a gear up landing due to an electrical failure. We have had a lot of gear up events on KR so my money is even on odds for which way this report will go: pilot error or mechanical failure.
DeleteRegistrant's website shows the aircraft as one of two for rent or instruction. PF not ready to do the emergency extension or forgetting the gear in all of the excitement is possible if it was rented for the trip.
DeleteIf ldg gear does not check down and lock
1.Ldg Gear Pump C/B..........................PULL
2.Gear handle ...................................DOWN
3.Emer gear knob ...............................PULL
.........................while fish tailing airplane
(approx. 10 sec to down and lock)
I am the owner and pilot of the aircraft and was PIC when this occurred. My first indication of an electrical issue started ~45minutes before landing. I was on an IFR flight plan even though it was VMC. I was in contact with ATC and informed the controller that I was having electrical problems. I started to shed electrical load by turning off autopilot. I was not declaring an emergency and the problem had nothing to do with the ignition system and the engine was running well. There were no good landing options and I felt the best thing was to land at the airport (KOUN). The controller informed me that I was number two to land and was cleared for the approach. The controller told me to switch to tower. Just as I clicked the mic to copy the frequency change I lost all electrical power including gear indicators. I put the gear handle down. I had no gear indicators. I lined up for final. My wife said "I did not see three green", I replied that I agree because we do not have electrical. I held the manual gear handle down. My airspeed was ~95knots and I extended flaps. Airspeed dropped to 85knots. These are my normal landing speeds so I thought my gear was down providing the drag I usually have. As we landed my sight picture looked lower than normal and just then I heard the scraping of metal. The engine was at idle and the prop struck the runway. when we stopped I turned to my daughter in the back seat and said we need to get out. She asked why we were getting out on the runway. She didn't realize it was anything but a normal landing.
ReplyDeleteThe engine shop determined that the alternator stopped working.
What I learned from this experience:
1. I need to learn crew resource management. I didn't effectively leverage my wife who was in the copilot seat. I should have asked her to use the standby radio to call tower and confirm our gear was down.
2. There is time to think during an emergency. My tunnel vision had me focused on getting the plane on the ground safely. I did consider a go around but without radio communication with the tower and since I was cleared to land, and in a stabilized approach I felt the best option was to land before anything else could go wrong.
3. When I had practiced emergency gear extensions previously, I had gear indicators to confirm the gear was down. I'm open to suggestions on how to tell the gear is down without electrical indicators? Should I consider backup battery system just for gear indicators? Has anyone done that?
I also own a PA32R-301T, a 2006 Avidyne model. Sorry to hear about your incident. I hope insurance will make you whole and you’ll be flying again soon. As far as verifying gear down without electrical power- there are various option for convex mirrors fitted at the wingtips that will give you a visual indication of gear down (not necessarily locked though). But following the book procedure should bring the gear down solidly once you unlock the manual extension knob safety and pull it out. If nothing else the mains will lock, the nose might lag if your airspeed is high.
DeleteI’ll also add that the 2006 PA32R-301T has a standby B&H alternator, which would be my out should I lose main alternator power. As an added redundancy I’m installing at battery backed GI-275 attitude direction indicator/MFD in place of the factory Mid Continent electric AI this annual.
DeleteFinal thoughts, a handheld radio is a useful addition to the cockpit. Newer models can Bluetooth to your Bose or Zulu headset. I’ve actually called a tower on a cell (years ago) to get a landing clearance for a Skyhawk that I was ferrying that lost its alternator. Tower numbers are in ForeFlight. Blue skies brother!
DeleteThe "What I learned from this experience" list left out the most important revelation of the event, which is the well understood importance of making an expedient precautionary landing when aircraft systems act up instead of limping on toward a preferred destination while hoping the problem doesn't grow.
ReplyDeleteThe Flight track log's aircraft position at 45 minutes before the gear up landing has coordinates of 35.5066, -95.3892, which is just 10 miles south of MKO, Muskogee-Davis Regional Airport.
Here is that map-pinned aircraft position, at landing minus 45 minutes:
http://maps.google.com/maps?t=k&q=loc:35.5066+-95.3892
By continuing on to complete the 110 miles remaining to reach preferred destination OUN instead of descending to nearby MKO, the pilot knowingly conducted a battery discharge test flight which is the root cause of the gear up landing, not the malfunctioning alternator or whether there was proficiency in emergency gear extension.
Knowing that the magnetos didn't need battery power seems to have been one of the bias factors for rationalizing the unwise decision of continuing on to get all the way to the preferred destination. The load shedding action indicates awareness that battery discharging was underway.
Being focused on getting the plane on the ground safely needed to happen when the electrical issue first started instead of pressing onward 100 miles further than required while the battery discharged.
It should be understood that not landing at the nearby regional airport to diagnose and correct the electrical malfunction while maximum battery capacity was still available to support extending the gear and lighting the green lights was just another example of get-there-itis.
It's time to be humble and teach that supportive family crew member sitting beside the pilot in the right seat about the failed ADM of the accident day. That will do more to protect the family from repeating the preferred destination flight continuation mistake during a future electrical anomaly than cobbling together a backup battery to light the greens or buying an emergency radio.
Accident day flight track log:
https://flightaware.com/live/flight/N83615/history/20211016/1600Z/KBYH/KOUN/tracklog