Author: jerseysherwood

Rotax – Progress

Now I have the shiny new permit for 12 months.. time to consider 2026.

The great work by Competition Fabrications has got the exhaust pipes neatly tucked in and both oil and water coolers neatly positioned

Next stage is to consider what options there are for cowls

The ideal would be nice curved alloy ones but price could be expensive … need to get some measurements to progress planning

The depth of the planned eProp is much less than the Hercules wooden one so that brings the front cowl much closer in and closer to those hot exhaust stacks

Ideally we need a hinged top surface cowl .. that can open both sides and secures against bulkhead and nose cowl

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Permit awaiting and impending storm

Waiting for the full permit .. BUT LAA have signed off and approved the repairs and the test flying that accompanied it !

With a hefty storm (Benjamin) on the way .. there was a smallish window on Sunday to get a last flight in before wind and rain spoiled the next 7 to 10 days 😞

With the new (front) battery in the start was pretty much instant .. but drizzle was definitely just a few minutes away ..

Decided to make it a pretty quick and short session.. once pul temps were up to 50 and the preceding aircraft had landed (such a quiet strip.. and you go to line up and someone’s on long final!).

So, with 2 teardrops from 01 (take off) and 19 (loop back) to land back the other way, and repeat the other way … managed 4 landings in 9 minutes .. bringing the total landings for the Ranger to 436 to date.

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VNE – to dive or not to dive – that is the question

I conducted the air test recently. A cockpit full of cut down LAA air test forms (14 pages therein) .. all reduced in side to A5 and clipped onto the clipboard so that the open cockpit flight didn’t spray it over the Norfolk countryside like confetti !

This gave me all the 100s of checkpoints for the flight test that I could capture for the subsequent manual form completion on the ground (quite why we havent got an editable version of this or an online Database escapes me)

Strapped in and headed off for a tight climb up to 3,000′ and then power back and into the dive ..

I remember the first one of these i did in a Stampe SV4C over La Rocque on the SE corner of Jersey, my inspector Bob Wright sitting in the front with a big checklist .. shouting what he wanted next.

I started at 3,500 over the sea and actually ran out of height before we got to VNE as i chickened out of the hard push required and we had to do it all again .. Bob laughing away up front !

This one over the flat Norfolk countryside i pushed over and altimeter started to unwind.. the noise builds and wind rushes ever faster as you tuck yourself behind the windscreen and keep a good eye on engine revs to prevent overspeeding.

I started to ease out at 87mph and felt that was fine.

Im never going to go that fast between now and the next flight test in 12 months time.

Dutifully submitted all the numbers to the LAA only to have pushback on the VNE. Why handnt I done it and yes, I needed to reach manufacturer’s VNE of 100.

Today, on a pretty cold October day, ive just nipped up to 3,000 .. pushed harder and reached my paint marked 100 on the ASI

Updated details sent in, hopefully for the reissue of the FULL permit (currently flying on a temporary one to allow test flying)

As you may surmise .. im not a great fan of the VNE test

  • Yes the manufacturer has set this limit to demonstrate a ‘top end’ limit
  • Do I EVER fly anywhere near that limit in all my general day to day flying
  • NO
  • Maybe just over 50% of that speed is normal and achievable cruise speed with the current approved engines.
  • So why do we expect pilots to push the airframe to that once per year ?
  • Is artificially stressing the aircraft once per year deemed a good thing ?
  • Its not like a benign stall test that you can do at height and have loads of margin for recovery
  • At the bottom of the dive you have the potential for significant things to happen
  • Your margin and recovery options are, by virtue of that round out speed, limited
  • Recovering needs to be gentle and controlled and I would argue that recovery is another significantly critical phase of this manoeuvre
  • If a pilot does this only ONCE every 12 months surely we are failing the ‘recency’ measure the LAA put so much faith in ?

Anyway, rant over, one whinge isn’t going to change the world.

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Battery uplift

So, as the colder days begin.. the battery had decided to play up and starting has become a slight ‘fingers crossed’ affair !

Way back when I put the first battery in i selected a motorcycle unit that fitted neatly into the TLAC kit supplied tray.

This was mounted in front of the passenger seat but, on getting around to weight and balance, I realised I needed a lump of lead in the tail to get CofG in right place.

Having made a small mount for the lead and fixed it.. the LAA decided they didn’t like a lump of lead in the tail that could head forwards in a nose in crash so rejected my plan.

I then realised that the lead weighed the same as the battery I had, so had the brainwave of removing this pointless excess weight and putting the battery in the tail with a proper supplied battery mount. So, nice and secure but hey presto I didn’t need any additional weight to achieve equilibrium.

This meant I needed to run quite long power cables up to the starter solenoid and also an earth to the engine… and this, over time, proved problematic as the power loss over some 4-5m of cable was evidential

I started to look at the lead into the fin post idea but then hit on the idea of using the priginal front battery location AS WELL and connecting the batteries together… in series..

This gave superb starting and you just had to breathe on the push button starter and boom into life !

Roll forward through the years ..and motorcycle batteries aren’t great. They definitely have a shelf life after which you simply need to cycle them.

I checked back on the one that i had in the front yesterday and it’s 5 years old !

The £100 ish to replace far outweighs the disappointment of a none start !

The tail one i believe was done after I got to the UK and, the last time I did it, I made a small cut out Oratex panel that will allow easier replacement (the whole side of the aircraft being one complete piece of Oratex).

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Flight Test

So, after a few ‘fettling’ sessions as they are known.. where you fine tune this and tweak that ..you reach a point and a day.. where aircraft, engine, weather and time all co align and you can carry out the flight test.

The Light Aviation Association (LAA), the governing body for homebuilt and other registered aircraft, have a plethora of forms and process that you need to follow on a regular basis to ensure your annual update is up to spec

Add into this the fact that yiu have had ‘an upset’ and this brings in additional checks and balances

All very sensible stuff to ensure you have ticked every box and thought of as many eventualities you can.

The ‘changes’ to my aircraft, post the incident, meant that I needed a full flight test. 14 pages of check items to run through.

I cut all these 14 pages into manageable half pages so that I could have them on my knee board in the cockpit and then attempt to capture all key information during the test flight.

The problem with lots of bits of paper in a small open cockpit is that its a bit blowy and tricky to keep your notes !

The initial power out climb was a very long slow orbit slowly climbing at a constant attitude for nearly 5 minutes.

The old overheating of the cylinders was pretty much gone and I timed each 500′ ad it went.. turning out to be about 600feet per minute

Once I reached 3,000′ it was getting quite chilly and so all temps were looking absolutely fine. I then captured all the vakue on the way up and then eased the throttle back and into a dive

The aim of the dive is to check VNE .. ie never exceed speed .. which is 100mph.

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Torque check

Having had a the dreaded flu for a few weeks it was time to check the torque settings to update the log book during these early test flights and getting her ready for the air test.

With torque set to 32nm pretty much every bolt was spot on .. one or two took one extra crank to bring them up to spec.

Jabiru are renowned for wandering out of torque and it only takes about 20 mins to check all the bolts .. remembering the hidden one inside the rocker cover behind the small grub screw.

One thing I’m not mad about is the lipstick

Its calibrated for the Jabiru 2200 BUT in trike mode … and the Ranger obviously sits on the tail. This means you are constantly making that mental switch on reading.

The sunp is so pitifully small anyway and James (the Chief engineer at TLAC) always used to say just put a piece of thin wood down to the very bottom to see what is actually in there !

Keeping a very close eye on oil levels as I run-through the first high powered climbs and check it on cool down EVERY flight

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Overall flying locations

Over the years its been great to have the chance to fly lots of places with many many people …

Even though the advent of airborne GPS was a relatively late addition for me, apps like SkyDemon have been a revelation

They have simplified not only advance planning but in flight changes due to usual bad weather that usually ‘unexpectedly’ happens in the UK

I was delighted when Skydemon further developed their already amazing software to add auto route tracking over time with a map overlay

This shows mostly Jersey based starting points and flying to various places in amd around the UK as well as France and Luxembourg .. many small airfields with friends to pickup pups or business trips to various European offices

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Flying videos

Its so nice flying out of such a friendly local airfield .. always someone around to lend a hand, pass on great skills and be that friendly guy who takes the trouble to video some of your initial circuits post the rebuild

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Hands up …

One of the tests after (significant) changes to an aircraft is a full flight test … before that..you just want to know “Does it still fly straight and level” .. without too much heaving on the stick.

A small test i did on Monday was to get up to around 2,000’… wind on the ground was varying between 11 and 18kts so it would be a bit stronger up there…. and LET GO !

Looking at little like a hijack (but no gun involved 😉) i trimmed, let go of the stick and did a 1 min 14 second turn….hands off .. just judicial use of a bit of rudder to coax her around

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Cooling – Next Check

Id been thinking about the hot running head and thought the damage to the lower cowl meant we needed to repair and beef up some of the lower curves.

The original holes in the lower cowl were primarily around exhaust exits, a small hole where the exhaust silencer block touched the cowl, the oil radiator and feed pipes and some cut outs to accommodate the cylinder heads.

The accident crunched the oil radiator into the lower curves of the cowl and that needed beefing up and neatening

The net result was a super strong and great gloss finish but some holes were either enlarged or simply aren’t required anymore.

To test my theory out, without the need to do any ‘hard acts’ on the cowl , I planned to use tape to temporarily block off some of these holes and double the tape so that it would survive a short (30 min) test flight.

A short test flight, which ended up being 41 mins, proved very successful.

Even powered climbs were better than they were before.

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