Engine – ground run testing

As quite a lot was changed and updated the engine needs a careful planned set of ground run tests.

The first involves a short 1 min run and then removal of each rocker cover to check oil is indeed being pumped around each bore

It’s now been converted from Hydraulic lifter valves to solid lifter valves, the old way (hydraulic) meant that I didn’t have to do any valve checking as they self adjusted. Now I need to include regular movement and gap checking.

The checklist calls for around 10-15 timed and controlled runs .. starting with low revs ..up to 1200 and short runs just to get all oil distributed evenly.

It’s always a pain when you have emptied the oil cooler matrix – this is a new one so starts empty ! .. you need to allow for sufficient oil in the sump to fill that and perhaps any new filter that may have been added.

The dipstick on the Jabiru isn’t the greatest piece of metal known to man as, in the taildragger configuration, you don’t get an accurate reading, the dipstick being calibrated to read when the engine is in a flat orientation. The standard dipstick doesn’t reach the bottom of the sump !

Over and above the standard dip test every flight….I’ve got used to checking every so often by trestling the aircraft up to flying angle .. ie Straight and Level (you need to do this when occasionally checking the rigging and wing dihedral). Anyway, the standard dipstick mark is ignored and it’s ‘about’ 1/8” (in old money) covering the bottom tip of the stick.

At the last annual James, my engineer, grabbed the prop ..pulled the engine into its S&L position and put a stick down to check… the simplicity of this was quite obvious … vs ‘it should be about 1/8 on the bottom of the stick’ .. so I’ve created a new dipstick that goes directly to the bottom of the sump.

The remaining tests slowly take the revs up through 1800 block tests as they call them .. successive run ups and cool downs … giving you chance to check all is working.

Once you get to the 1800 tests the idea is to take it to 50’C oil temperature and THAT should open my TOCA – Thermostatic Oil Cooler Adaptor .. a neat slim block that fits between the engine and the oil filter effectively blocking (COLD) oil circulation until the engine reaches 50.

The subsequent runs take the revs up to 2400 which is where it will be difficult holding her on the brakes so the chocks will come in handy … pays to keep the elevator back in these power checks !

Engine back and installed

Forgotten I had missed writing this post … long awaited update to engine and all put back in place

Took the opportunity to replace old hardened engine mount rubbers that had started to craze… also freshen up odd little scrape on the engine mount with hammerite … wish I’d still been around Jersey and my friend Mike Flemings powder coating skills !

Refit was a breeze … slight jiggle whilst the whole thing is safely suspended on a car hoist makes it a bit like a lunar docking … getting all 4 lugs neatly aligned and NO pressure on them until nuts done up

Then set about removing the awful (my word) wiring block and replacing with much nicer quality unit and a chance to really check each end point and put new crimped ring ends in position

Also make sure that L and R CHT and EGT are indeed LEFT and RIGHT !

Updated joystick end

My old joystick end had hardened rubber surround which was making the alloy PTT switch slightly loose, so time to replace … and add something extra

Having researched the market there is a very smart Allen head that offers a PTT plus … he ability to have other electrical operated without the need to remove your hand from the stick ….

Currently my smoke system needs me to take my hand off the throttle OR across over with my right hand in an already small cockpit … the smokingairplanes u it does, however, come with an additional ‘intermittent’ option which, when wired to a suitable switch, allows smoke at the touch of a button …

The slight problem is that the Allen head is quite large and with my panel design having a slightly lower line for fuses .. the two meet! So I needed to take a small amount off the end of the stick.

The tricky piece is you DO NOT want any burr dropping down to the base of the stock unit. So, rather than a saw cut action, I bought a larger diameter pipe cutter that made a perfect job. Less than 60 seconds and your are left with a very neat, slightly sharp edge (inner) and smoother chamfered (outer)

The two new handshakes allowed an easy connection to the existing PTT circuit ..leaving about 10-15cm of cable for ‘working-wiggle’ room if I need to pull them out again. So many cut things super short and it makes it almost impossible to get crimps or soldering kit in there if needed. (The cloth pushed into the joystick tube above is to prevent any debris disappearing down the tube during this operation).

The tricky bit was then to thread through the additional cables using locking wire as a guide and tape hook arrangement to pull them down the tube and exit part way down the stick .. one will be a new dedicated earth ..the other a dedicated power to the head (when needed) and a final 3rd cable to handshake into the smoke intermittent earth socket.

Movement in the hanger

My current location in the hanger has been great as I have been pretty stationery whilst getting all bits tidied up and ready for flying again soon.

When I do move again … I have to pull a few aircraft out and about .. a lovely little blue Thruster called Millie … a gorgeous Blue Chiltern and a Kitfox …

The chance came to switch with the long term Jodel resident at the other end of the hanger … this would mean I just open 2 doors … pull out .. and the entire runway is directly in front on me … fantastic

Switched the 2 today and took the opportunity to give the lovely little Jodel and good wash down then moved the ramps to align with the Ranger tracking and then oiled and greased the hanger doors

Long awaited engine ground run …

So after a hugely long wait .. the engine is back in … new valves, new pistons, liners, new rings, beefed up and drilled flywheel access to make it easier to check bolt torques regularly … sand blasted and repainted

The new prop on and wheels out of the hanger for a first hot start

I’d opted to leave the cowls off and the spinner off so that I could easily check engine oil temps and possible leaks and bolts.

Recorded each session from a side on iPad as I can see the engine from inside the cockpit …this was to prove useful

First start didnt start immediately as there was no fuel to the bowl. Then it burst into life …first test called for 1200 tick over for 2 minute ..all temp and pressures looked great except one CHT, Left one read minus …turned out to be wires switched ..only one mis wire in the full re wire 😊

Stopped after 2 minutes and removed all rocker covers in turn to check oil and temperature … all looked great

Let it cool down and 2nd run … let the oil come up to temp and then run a little longer … to get oil to 45-50’.. took a while as the engine was completely open so very cooled by the prop wash .. she had now had around 20 mins of run time and all was looking great … good pressure of 65 and temps all well within limits.

Still not going through the TOCA oil limiter .. so need to keep her at above 55’ for a little longer in 3rd run

3rd run started instantly following cool down … this run called for 1200 for 1 minute, then 1800 .. this being a block that would repeat and cool down between each

Then, at around 3 minutes into this run up , and just after I’d started to ease up to 1800 … all was sounding smooth then there was a loud crack .. it didn’t sound metallic but thoughts immediately went to the newly refurbished engine

As soon as the crack happened I hit both mags off ..stopping the engine immediately

I turned the engine very gently by hand and all sounded fine and smooth .. no obvious mechanical issues ..so I removed each of the rocker covers in turn to check valves were rising and falling .. all were .. so what was wrong ?

As I checked the last set of valves .. I removed the cover . Reached up to the prop tip to pull it through … and felt the tip was damaged. On farther investigation it looked like a bit of delaminating and a small strike on the hardened leading edge.

Not a clue what had caused it .. a taildragger prop is about 30” from the ground so highly unlikely to be a flicked up stone .. and we were on hard smooth concrete anyway

Watching the video back at that point and enlarging it and slowing it down .. you can see the problem ! As I’d left the spinner off for the ground tests I’d (stupidly) left the 6m hex bolt in the end of the spinner spigot

With successive runs this bolt had unwound .. and, as I approached the 1800 rpm test it reached the end of its thread and came out .. hitting the tip of he prop at prob something like 400mph

Now the task of trying to source another prop as soon as ….😔

Keeping your hand in … whilst waiting for engine upgrade

My engine has been a while having its hydraulic lifter valves converted to solid lifters ..so apart from a number of PA28 trips to Jersey and back I’ve had very little biplane action !

Paul at TLAC v kindly said we could blow the dust off G-TLAC and keep my hand in ..

With one of my sons now working at TLAC and also part way through his PPL he was also very keen to get an eye on flying this fantastic little aircraft in and around tight grass strips vs the large controlled airspace of Jersey International Airport that we are both so used to !

U.K. winter flying – Norfolk – Little Snoring to Jersey

Having waited for the huge winds to ease we finally set off to head down to Jersey from Norfolk

Our ‘normal’ routing is, shortly after takeoff, to slot between RAF Marham and Mildenhall and USAF Lakenheath …but … today .. part way through the route the US air traffic suddenly changed their mind and asked me to turn around and head the opposite way as 15 US F15 fighter jets streamed in for landing.

The resulting detour and headwinds to get back in track left our generous fuel reserve somewhat lower than we would like … an hour from the South coast to Jersey would only leave us 40 mins to get down ..and low visibility was forecast

Goodwood advised they were closed to fuelling so a hop further along the coast to Shoreham who welcomed us with a nice tight overhead join to descend left hand down to their into wind runway .. some 34+ mph winds !

The quick refuel and last hour down to Jersey had 2 temporary diverts in the direction of Guernsey as Jersey dropped below limits. The second divert we opted to hold N of the island as it looked like clearing and we have good fuel reserves .. after another 20 min hold we got a slightly higher cloud base and in we went 😊

A Colour photo … believe it or not ..a very mono

The flight home was still pretty bumpy the following day but the Eastern route … going around the bottom of Gatwick and then up between Stansted and Southend

Arrival back after the much quicker flight back …34 mph 30 degrees off the runway .. made for an interesting approach

ITV footage of first flight

Digging through old videos and pictures …

On the very first test flight ..we had BBC TV and Radio and also ITV cameras turn up … I’m guessing it could have been a spectacular failure or .. actually fly !

I did the BBC live radio interview but can’t remember anything about it .. 2 mins after jumping out of the cockpit … then the ITV TV one … by the time I lined up for the BBC TV interview I just cracked up and couldn’t speak … it just all caught up with me 😊

You can’t practice .. as such … but I’d planned 3 or 4 hops before the actual circuit

Lovely to have real footage of the very first landing .. again .. you can’t really practice … although I had flown the early production model a few months before in Little Snoring

What I love is that I’d flown my Dad down for the first test flight and he was there, runway side, during the whole test jumps … interim rest-checkpoint and then the final proper full circuit

Also, lovely that ITV interviewed him .. lovely to hear his first thoughts and something to keep x❤️

Ongoing improvements

Over the years you get lots of little bits that mark the surface or don’t quite look as neat as they used to… one area this affects is the inspection rings I originally fitted some 5 years ago …

Over time one of two of these have started to show signs of movement and that in turn has made them slightly slack and the cycle then continues…

Add to that that I added a new inspection hole under the starboard wing when I was doing the annual but managed to make it a smidgen too large

I taped it up temporarily to fly back to Priory Farm but then decided to make a better cleaner fix

The whole underside of the wing is one continous piece of Oratex material .. as is the upper and each side of the aircraft.. this meant that to take out a full ribs worth I would have to make good a new ‘end point’

This turned out to be more successful than I’d thought… cutting out the now unsightly double holes.. I left a good 2″ inner overlap … then cleaned and removed old oratex edging and covering from any rib lower capping strips

Then glued using hot melt the trimmed the ‘new’ Edge piece and ribs and inner leading edge so that I could return the next day with the iron to secure all existing material … worked a treat

Then offered up my pre shaped full panel rib to rib and leading edge to trailing edge and glued, returned 24 hours later and sealed … almost drum tight even before heat shrinking … just a couple of overlap strips to add and then I can recut and reseal the inspection rings … in a sandwich this time .. to prevent movement.

Also … be nice to get all these small things done so it’s good for the winter season of flying ahead …. Ski gear all unpacked and ready ❤️

Dads funeral fly by

Sad day this week … Monday 11th was Dads funeral ..

As Dad was THE one who got me so into all things aviation it seemed a fitting thing to have both a ground and airborne tribute to him …

Positioned the ’plane from Priory Farm to Rougham having emailed fhem a few days ago to request permission to land and then return for the funeral fly by.

The day didnt start well as my Trig radio …. that hadnt missed a beat in 5 years of flying … decided to pop a message saying ”No radio” … i tried the usual off and on and even a quick circuit but no luck … i called the boys to catch them to drop by with the Icom handheld … this didnt work too well on readability at Rougham but got me in

later investigation and , in the fading light, i could see that the second radio head, in the front cockpit wasnt illuminated … traced it to a bad connector that probably got disturbed when i did the annual

Returned a couple of days later and stripped each heat sealed cover and re crimped

Video of footage from Rougham strip on the short trip over to Bury St Edmunds



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