Another flight after bungee undercarriage update
I was putting the aircraft registration into Google the other evening and found a load of random shots .. some mine but many weren’t… really nice photos that people had taken
Whilst awaiting the return of my leg with a new rubber bungee it’s good to take the time to get the bugs out from inside the wing and grease up parts.
The wing inspection panels come off in about 2 mins and you can then get to the lower aileron bell crank (the bit of metal that turns the latitudinal push pull into a longitudinal push pull and makes the ailerons bank the aircraft so smoothly)
Also .. to get all the old grease removed from the wing and rudder hinges .. cleaned down and fresh grease applied
So … the ongoing checks of my bungee that slipped off …
It turns out that, having sent the whole leg back to the factory, they have checked against a brand new bungee rubber … and ..
The effect of getting soaked in baby oil is that the rubbers have expanded … each strand is now fatter and longer !
The net effect is it simply had room to move …
I’m now going to condemn the other main gear bungee and work out a design to effectively seal the bungee from any moisture ingress but also allow movement
I will also do the same on the tailwheel bungee
No fault of design but a secondary effect of excess lubrication smearing means that the bungees have got a little moist EVEN though they are wrapped in nice leather boots
The net effect was that a bungee slipped over a bobbin and let the leg go slack .. well as far as the bolt stop point..
I created a temporary splint as I didn’t trust leaving the aircraft on a jack and axle stand EVEN with a ratchet strap between the two wheels
This will be really handy in future maintenance
Whilst lying under the tail end a few weeks ago .. cleaning and drying the bottom I noticed that there was a small scrape on the Oratex material that doubles over the metal joints.
it turns out that prolonged full left rudder turns over the 3 years plus has caused the cable .. that splices off the rudder cable to give left and right control on the spring governed tailwheel … has rubbed against the lower material covering.
An easy fix .. will cut a pinked patch of leather .. really degrease the tail end and stick it on the overlap joint
Well …. what do you get when you mix rubber and oil … there may be a few answers but probably an underlying theme will be nice lubrication !
Its not so nice when it comes together at an area where you probably don’t wish to have quite so much lube and slip …
3 smoke flights in and I was on my 7th or 8th landing post the addition of the smoke system … and I realised I was getting some of the excess oil over the tailwheel .. I made a small leather boot but it was already pretty moist.
On the 8th landing I got quite a bit of wheel shimmy at the end of the roll out …. on parking up i wondered if it was a bearing … but on investigation proved to be an interesting small problem….
The oil had wet the tailwheel bungee rubber and then the ‘loop around’ had slipped up the tailwheel shaft and popped onto the (smaller diameter) main shaft. This had the effect of slacking the support .. hence allowing the natural resistance of the bungee – Now gone – to let the wheel have more free movement.
Easy fix .. clean it all down and remove the oil and then cable tie the bungee top and bottom loop together
With my annual permit expiring in 3 weeks it was time to meet up with the inspector to check over the aircraft and then conduct a flight test to monitor and check all the numbers ….Climb, stall, temps, pressures, speeds …. play with the clouds comes free