On December 30th I flew to David Wayne Hooks Memorial in Houston to see a friend. The intention was to travel down at lunchtime, and return in the evening.
All went well, until I prepared to leave at 8.30pm. I put 20 gallons of fuel in the plane, since the self-serve fuel price at the airport was an extremely good $2.85. After completing fuelling and external pre-flight, I lowered the nose gear, got in the plane, cycled through the checklist, fired up, and went to move off.
As I was slowly getting under way, the nose of the plane abruptly dropped to the ground with a dull thud, accompanied by a "zzzzziiiip" noise. I was probably doing about .5 mph at the time, so there was no damage except to the nose snubber (a piece of hockey puck), which was knocked off in the impact.
My immediate reaction was "that shouldn't have happened"... I cut the engine, begged off my clearance conversation with the tower, and alighted from the plane. The nose gear strut was almost all of the way retracted, the forced retraction having stopped when the nose snubber contacted the ground.
A couple of guys from the FBO helped me to lift the nose and move the plane off the ramp to a parking area. Once there, I opened the nose panel and removed the gear cover. As I suspected, a feel of the underside of the worm gear wheel confirmed my suspicion - the teeth had stripped from the gear wheel. Almost certainly this occurred because the gear was not over center and locked when I got in the plane. A classic error that I had avoided making - until now.
Anyway, here I was, at 9pm on 30th December, away from home, with a damaged plane. What now? On a dark and cooling night, there was no point in attempting any repairs immediately. I phoned Mary with the bad news, and went back to my friend's house to stay the night.
Time to start ringing around. Ironically, I had a 2009 Central States Association roster in the hangar - but in Lancaster. No roster in the plane, but some phone numbers in my cellphone. I started making calls. After a while I got a message back from James Redmon with a list of numbers. Doug Bryan responded to a call from New Mexico, and gave me more phone numbers. I talked to Jesse, who reminded me of the 180 gear flip option.
In the morning, I started getting calls back from people. I talked to Bob Sudderth, who confirmed that I would need to remove the retrac mechanism from the nose box to work on it. We agreed that removing the canard was also likely to be needed to provide sufficient working room.
Jim Voss and Ryszard Zadow called me back. Jim offered to donate his entire manual retrac mechanism, that he had removed from his plane when he installed an electric nose lift. Ryszard, fresh from an early morning duck hunt, but needing to go to his day job, passed my details onto a friend resident at Hooks.
By 11 am I was back at the airport and a plan was taking shape. Jim Voss would fly his replacement retrac mechanism into Hooks for me at lunchtime if I needed it. Chuck Scott, Ryszard's friend, showed up with his friend Mike Hergenrather. By the time they arrived I had already removed the canard and was working on removing the retrac mechanism from the nose box.
The retrac mechanism is attached to the nose box by 5 bolts - 2 through bolts with spacer s that position the mechanism accurately, and 3 bolts that additionally secure the frame to the nose box.
The challenge when the gear teeth strip like this is that in my case, the gear mechanism became locked, since the stripped teeth were stuck in the worm gear. Additionally, the gear is not fully retracted. This in turn creates the issue that you cannot easily remove the bolt connecting the gear strut shock absorber mechanism to the retrac mechanism, because the bolt is not aligned with the removal hole in the side of the nose box. I was able to only get the bolt part-way out. This left me with the retracted strut, shock absorber and pivot creating a large block to undoing 3 of the attach bolts. I have small hands, which helps in a situation like this, however, it took a long time, with much use of words of which my mother would not have approved, to undo the 3 reinforcing bolts. I eventually did it, after which time I discovered that moving the mechanism around inside the nose box freed up the worm gear mechanism, which allowed me to wind the gear up to the point where I was able to remove the attach bolt for the strut. After I removed the bolt, I was able to then rotate the crank mechanism to the point where I was able to remove the bolt connecting the worm gear universal joint to the crank arm. After doing that, I was able to pull the entire mechanism out of the nose box.
Inspection showed that the cranking worm gear was undamaged (clearly that is a lot more durable than the gear teeth...), but that 120 degrees worth of gear teeth were stripped from the gear wheel. The repair was either going to consist of using Jim Voss's replacement mechanism in its entirety, or flipping the gear wheel 180 degrees to use undamaged teeth.
At this point in time, I took Mike up on the offer to use his hangar. We attached the nose of the plane to his low-line trailer with straps from the trailer to the nose bulkhead, with the nose resting on tarpaulins and towels. We then towed the plane to the hangar at the other end of the field. We proceeded at 5 mph down the taxiway, with me sitting on the nose of the plane to hold it in place, doing my best Slim Pickens impersonation, waving to puzzled spectators.
Mike lives in a superb hangar home on the South end of Hooks field. We pulled the plane into the hangar, then went back and picked up the canard. Shortly afterwards, Jim Voss arrived, having commandeered the Gill Aviation fuel truck on arrival to travel to the hangar. He handed me a complete retrac mechanism in a box, then headed off to Austin to visit family.
I compared Jim's mechanism to my removed mechanism. It was identical to my mechanism, but a couple of the attach holes seemed to be slightly differently located when I trial-fitted it in the nose box. This led me to decide to try the 180 degree flip on my gear wheel instead.
The gear wheel is fixed to the rotating gear lever shaft with 4 screw-bolt fixers. I removed the screw-bolts, rotated the gear wheel 180 degrees, re-attached the gear wheel with new locknuts on the screw-bolts, checked that the full up and down travel did not result in stripped teeth on the gear wheel contacting the worm gear, greased the mechanism, and then began the process of re-inserting it in the plane. Mike was providing sage advice and a large tool store, derived from years of fixing many different types of planes. He also picked up the bolts that kept falling down to the bottom of the nose box, due to being dropped as we tried to manouver hardware into confined spaces...
The ability to move the shock absorber out of the way and crank the gear pivot up and down made re-inserting the mechanism somewhat easier, but still a physical challenge due to the confined space in the nose box. I still have the bumps, scratches and bruises on my hands as proof as I write this...
By 5.30pm we had the entire mechanism re-installed. Ironically, one of the most frustrating parts of the repair was an entirely peripheral issue - when I tried to move the blocked mechanism by rotating the hand-crank in the morning, the flip lock-lever on top of the hand-crank popped out, with the circlip. Getting those small parts back in place proved a challenge, due to the lack of a suitable tool, and Mike ultimately did it by hand (I'm still not sure how).
Some test cranking showed that the re-installed mechanism was working well. The big question that I was not sure about was whether there was still the correct tension in the shock absorber mechanism, which might have moved during the nose collapse. I could not see any evidence of movement of that assembly, so I decided to conduct a ground test of the repair.
After adding more grease to the worm gear and gear wheel, we re-installed the canard and I fired up the plane and went for a taxi test. During the test, I deliberately ran over bumps on the taxiway, and the cats-eyes on the yellow line in the taxiway, to test the ability of the gear to resist the bumps (although logically those stresses should be taken by the mechanism, not the gear, if the gear is over-center and locked.). Everything felt good.
So...at 7 pm on New Years' Eve, I lifted off from Hooks field and headed back to Lancaster. An uneventful flight, and a very smooth landing at Lancaster (it helps when there is no wind...). No issues when I lowered the nose...
The lessons? The main one is that the canard aviator community has a tremendous support DNA. I was deluged with offers of help, from all over the USA, and I am still getting phone calls asking me if I made it home OK. The most amusing call was from Bill Allen, who phoned me from Paris to wish me a Happy New Year, and then asked "how's the plane?".
The second lesson - never get in the plane without verifying that the nose gear is over-center and locked. The gear mechanism is merely a means to raise and lower the gear, it cannot take the load of the plane and passengers. I somehow avoided making that mistake for 8 plus years..but I eventually did make it.