Sadly, following a fuel stop in Coshocton, Ohio (i40) on Nov 1, my Legacy had an uncommanded nose gear retraction. The engine wasn’t running but the propeller was damaged. My poor plane is currently sitting 400 miles away in Ohio while the prop is out for repair.

 

Symptoms

A few weeks before the incident I extended the gear for landing and the pump kept running after all three were down and locked. I could hear that the pump was in bypass mode. When laying out the panel I installed the 2A gear relay breaker front and center next to the actuator switch so that I could easily practice emergency gear extensions. So I promptly pulled the 2A breaker. Guess what – the pump kept running! I had to ask my mom to pull the 40A hydraulic pump breaker since it is on the far right side of the instrument panel. That stopped the pump. Since I was at a strange airport I borrowed a screwdriver, removed the baggage bulkhead and began troubleshooting. A few raps on the faulty relay with a screwdriver handle fixed the problem. These are the Bosch relays that were recommended on the LML back in the late 90’s.

 

It happened a second time a week or so later. This time I was flying right seat working on my CFI-I. I pulled the 40A breaker then reset it and my instructor was none the wiser. I ordered replacement relays (approx $25ea). The relays arrived shortly before I had to leave on a trip and there wasn’t time to install them.

 

The Incident

I was headed from KHWV to 1H0, an 800+ mile trip, for LOBO instructor training and bucking a 45kt headwind with plenty of turbulence. Like most 2-seat Lancairs my pump will occasionally blip in flight if the hydraulic pressure sags. This time the pump blipped and kept running. Once again I had to have my passenger pull the 40A breaker. We briefed the plan for extending the gear. I would select gear down, then he would reset the 40A breaker, then I would reset the 2A breaker. We completed those steps but the gear did not extend. I flew an upwind leg at pattern altitude and performed an emergency gear extension. We landed normally and refueled.

 

My plan was to do some troubleshooting on the ground and pull the baggage bulkhead access panel if necessary. I double- and triple-checked that the gear selector switch was in the down position before turning on the master. The nose gear immediately retracted. It happens very fast since the nose wheel is perfectly happy rolling backwards with practically no resistance. The mains don’t move since they would have to be dragged sideways against the pavement. The plan fell with a clang and came to rest on the two lower prop tips of my three-bladed Aerocomposites prop. The lower cowl and nose gear doors never touched the pavement.

 

The cause (speculative)

I believe the up relay contacts welded shut due to arcing. Since the down relay was still working, selecting gear down closed the down relay so that the pump was being powered in both directions at once. This is why the gear didn’t even try to extend in flight. I have an airspeed switch to prevent inadvertent gear retraction below 90kts, but with the up relay welded shut it had no effect.

 

The plan

The propeller is on its way to American Propeller Service for inspection and repair. They will sand down the blades and inspect them to determine the extent of the damage. They will also inspect the hub since it must have taken considerable stress. Once the prop is back in Ohio I will fly out there, fix the gear problem, and THEN reinstall the prop (how ugly would it be if the plane fell off the jacks onto a brand new prop!).

 

Choosing your fuel stop

We chose our fuel stop by looking at Foreflight for good fuel prices along our route of flight. Since this was only a fuel stop we didn’t look at other amenities. It turns out that Coshocton Ohio is quite rural and our incident happened at 5pm on a Friday. The nearest rental car agency is in Zanesville, 45 miles away. To make matters worse, the town is in the middle of a 20-mile dead zone with no AT&T wireless coverage, making communication with the outside world very difficult. It took fair amount of complicated logistics to get ourselves to a commercial airport for the trip home.

 

Choosing an experimental propeller

Since two blades were facing down, one blade struck the leading edge and the other hit the trailing edge. The leading edge has a nickel alloy sheath that extends all the way to the tip. There was no visible damage. However the other blade’s trailing edge is very thin and flexible and was clearly damaged. Aerocomposites is no longer making propellers. They sold their technology to McCauley, but McCauley only plans to make certified props. The prop shop told me my prop has a carbon fiber core with a fiberglass outer layer. If only the fiberglass is damaged the prop will be repairable. If not I will have to either find a replacement blade somewhere or replace the whole prop with another brand.

 

Insurance

My insurance is up for renewal on 11/23. The renewal premium was $3438 against a $170,000 hull value. After the incident my premium was raised to $3781. I suppose I can’t complain since the repair bill will be in the $6,000-7,000 range, assuming the prop is repairable.

 

Safety practices during maintenance

I’m not sure what lessons I can pass along from this experience other than to be extremely cautious when troubleshooting gear problems on the ground. The only way to be completely safe would have been to jack up the plane before turning on the master. I found out later that the maintenance shop at this field is only open M-F 7a-4p so very little assistance would have been available until the following Monday regardless.

 

-Adam Molny

Legacy N181AM, 197.5 hrs and holding