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The next instalment in the CA510 110hp installation into a J160 is a bit overdue but here it is. The engine will require a 3” prop extension to fit nicely into the cowling. We are waiting for the extension to arrive from overseas. Once it does, the engine location will be confirmed and the mount will be final welded. In the meantime, the exhaust system has been welded up and looks very nice. The photo below shows the exhaust system mounted to the Rotax we have been using for mocking things up to keep the new Zonsen engine pristine until the final installation is ready. Hopefully the prop extension will arrive soon (it has been shipped so we are waiting for it to arrive) so that we can finalise the engine mount. Bolly is doing a special prop for us which we are excited to trial with this airframe/engine combination. The fuselage work is essentially completed but awaiting painting. The wings have been painted and are ready to go back on the fuselage. Once the engine and accessories are mounted, we will have throttle cabling and instrument wiring to do and then we are pretty well done with the installation.

We were in Kakadu several years ago..we went on a eco trip with an Aboriginal bloke..I was looking at his woomera.and I asked him what sort of resin did he use... answered with Sikaflex mate bloody good shit.. Bernie..

Well, I’ve just ticked over 1000 hours building, and that’s just the time in the shed. All the hours on the computer investigating options and sourcing parts are not included. Probably about another 1000 to go. Funny thing I noticed yesterday. With the heatwave, it appears that all my heat shrink tubing has shrunk a little. The size that used to slide over a spade connector now just doesn’t. Now all I need is for the heat to help my gut to shrink a little… 😛

Does anybody get the feeling we may have veered off from the theme of this thread? Some/many of the comments are getting a little to personal in my opinion. Perhaps it's time to call it quits and agree to disagree,

Don’t really see that French stuff as anything to special really. Each day every day over here

On a Rotax 912 (twin Bing carbs), that “balance pipe” is basically a plenum-to-plenum equaliser between the two intake sides. It primarily: Equalises manifold pressure between the two sides (helps share load between carb/intake pairs) Damps pulsations (intake pulses are strong on a 4-stroke, especially at low RPM) Can slightly influence idle/off-idle smoothness and how stable the carbs feel during synchronisation What changes if you go from ~8 mm ID to 20 mm ID? Area matters a lot. 8 mm ID area ≈ π·4² ≈ 50 mm² 20 mm ID area ≈ π·10² ≈ 314 mm² So you’d be increasing cross-section by about 6.3×. That means the balance connection stops being a “small equaliser” and starts behaving much more like a common manifold link between the two sides. Likely effects you’d notice (if any) 1) Idle and low-RPM smoothness could change (sometimes better, sometimes worse). A larger tube usually reduces pressure difference between sides more quickly and can dampen pulses more. That can make idle feel smoother if you currently have unevenness between sides. But… if you go too large, you can also create a situation where: one side’s intake pulses strongly influence the other side, mixture distribution and response around idle/off-idle can become less “crisp” or occasionally hunt/surge depending on how the rest of the intake is configured. 2) Carb synchronisation behaviour can change. With a big balance pipe, the two sides are already heavily “averaged together”, so: it may become harder to detect a small imbalance using manifold pressure/CarbMate-type methods (because the balance pipe masks differences), you might end up with an engine that seems balanced by reading, but still has subtle cylinder-to-cylinder inequality. 3) Midrange and high-RPM power: usually little to no improvement. At higher RPM and larger throttle openings, the balance pipe generally has minimal benefit because both sides are already flowing heavily and the pressure differences are smaller relative to overall airflow. A larger balance pipe typically won’t give you more power. 4) Risk of unintended side effects goes up. Going to 20 mm ID is a big jump. Depending on your exact intake layout, you could introduce: odd transients (tip-in / tip-out throttle response changes), cross-feeding effects if one carb is slightly richer/leaner than the other, potentially more noticeable issues if a carb/diaphragm/jetting problem exists (the big pipe can “share” the problem). The practical/engineering takeaway A balance pipe is usually sized to equalise slowly enough to damp differences but not so large that the two sides become one big coupled system. Jumping from 8 mm to 20 mm is not a small tuning tweak; it’s a redesign of the coupling strength. What I’d recommend instead of going straight to 20 mm If your goal is smoother idle / better balance, you’ll usually get more reliable results by: doing a proper carb sync (idle stop + cable sync at ~3500–4000 rpm), checking diaphragms, intake sockets, clamps, balance tube condition, and any vacuum ports/caps for leaks, confirming float levels and correct Rotax compliance items (many “roughness” complaints are float/diaphragm/leak/sync related rather than balance tube size). If you really want to experiment, a safer approach is incremental (e.g., 10–12 mm ID) and verify with: EGT/CHT consistency (if you have it), idle stability, plug colour / fuel flow consistency, and repeatable run-up checks. One key caution Because this is an aircraft engine, changing intake hardware can have certification/maintenance and safety implications depending on your aircraft category (RA-Aus, experimental, certified installation, etc.). Even if it “runs”, it may not be a compliant modification.

K&N air filters are the standard part in the 13,000+ Van's RV aircraft that are flying around the world. K&N air filters have been fitted to every Rotax 912,915 installation that i have seen. K&N air filters are fitted to many other experimental aircraft, example Glastar. If there was a problem I think we would know about it by now. Over priming, carb leaking, fires that happen while attempting a start will happen regardless of the air filter type. We had one such case at our airport last year, an RV with a K&N air filter, surprisingly there was no damage to the filter itself. I got to see all the damage with the cowl off.

Are you saying crossing the plug wires to clear the carby jets is not a good idea? 😁

No Joke is NO Joke. If you feel like a fool there's Plenty around. To err is Human. To forgive, Divine. er, or something like that. IF you haven't MADE a Mistake , chances are you HAVEN'T Made ANYTHING.. Nev

This. We appreciate the observation about the proximity of the exhaust to the oil filter. Appropriate measures to reduce or negate the proximity of the exhaust to the filter are being adopted. Future posts will show these initiatives.

34 years ago we did a trip to Ayres Rock and took the aboriginal tour around the base. The old gin showed us how they extracted the resin from the base of the spinifex grass by placing it into a coolamon and belting it with a stick. The resin mixed with fragments of grass, then she heated the coolamon over an open fire melting the contents into a bitumen like goo. She then demonstrated its use for holding stone spear tips and axe heads in place forming the hot solution with her bare hands. Each of the children received a stick with a ball of resin on the end, like a lolly pop. She (or the translator) said to reuse it just reheat it and that's all they had to do to change a spear tip or axe head. My son still has his memento that he received at 8yrs of age.

Nev, I get that you post things to enhance aviation safety. To suggest that the engine or wind was a factor just muddies the water and detracts from the learning experience. The copy of the cctv i have is quite clear, the camera is tilted at a 16° angle relative to the runway , the Cessnas spinner to tailcone is at a35° angle . Wing angle of incidence would be similar. Yes the aircraft was initially climbing which would have reduced the angle of attack. Once the aircraft stopped climbing critical angle was achieved. 35°-16°=19° That will do it. This video and there are plenty more like it if one goggles "cessna 172 stall crash" should in my opinion be mandatory veiwing for all student pilots.

I think you've just described the occupant of the Oval Office.

Ha, ha ... but then, the PNG mob says the same about the NZ mob. Anyway, the bent-wing hill-tribes should support each other. What's a Jodel, after all, but a juvenile Fletcher?

apologies if you have heard this one ............... no joke though Onetracks post above reminds me of the NZ topdressing DC 3's that could take a Bambina or a Mini in the back - also by ramp - for transport of pilot and crew - pilot got off one speeding ticket in the North Island ................. BUT, presumably had to pay the South Island ticket ! (post form NZ web-site below) Was it Gerry Kluck that got two speeding tickets in a day (within the hour I think), one between Blenheim and Woodbourne followed by one from Paraparaumu Airport to the Railway Station. (so engineer could catch train to Palmy)? Magistrate through it out of court as it was thought impossible to get two tickets within three hours in two islands in the same car.

If you are belching out 2mt flames a change of diet may be in order

Oh, "Crosswind" in the thread title refers to the video linked in the original post (mid 2023). Just keeping the little collection together.

There's ONE Bristol Wrecked at the Bottom of a Hill. They Just removed the Engines and Left the rest there. In the Mid 60s I crewed DC4s to POM-LAE overnight LAE. Frequently we were about 500 Ft above the terrain over the OWEN Stanleys at about Flt LVL 150. If it wasn't VFR the LSALT was FL 170 coming back. The High speed selection for the Blowers was removed On OUR C47/DC4 Planes Guaranteeing we Couldn't Maintain Height If any engine failed. ALL approved BY CASA or DCA at the Time. ALSO the PNG Fleet operated on PK Charts for MAX Weights. ((Developmental) allowing them to be Overloaded compared to Mainland figures. How good is that? Nev

Now I am worried I am going to be flying through a sandstorm belching out 2 mt flames.😁

We will be to scared to fly if we read much more of this.

Lucky they are in a clean environment .would you prefer a Donaldson cyclone hanging off the side.🤣

No doubt we're polar opposites. I'm a little casual however I operate on prior knowledge. I didn't spend a lifetime in mechanical engineering without picking up a few clues along the way. As I said before heading to Melbourne "If it starts and runs without overheating it'll make it across the Nullarbor". That doesn't mean I don't take care, I just know what I'm doing in most situations. If the vehicle was to hiccup along the way I have what it takes to sort it out so I take on things that some may find risky, for me it's a calculated risk. I'm yet to learn aviation and I'm quite aware that I'm in the high risk category where the casual approach can bring somebody to an untimely end however I've passed the last 72 years without a vehicle accident (non-competition) or serious injury so I think I have a fair chance of getting it sorted.

DUCT or DUCK, pffftttt. It's just not worth getting your feathers ruffled over.

That should be standard practice. If there is a carb heat device fitted, it is there for a reason and that is to help avoid carburetor icing. By just dismissing it as not necessary is poor judgement and passing this on to students is poor management. Carburetor icing can occur at ambient temperatures up to 35 degrees under the right conditions.

My father in law had a Tecnam P2008. Every time you pulled the carb heat knob your feet got hot. It might have said carb heat on the knob, but it went to the cabin heat. (Came that way from the factory)

Also see very little carbon when examining the cut open oil filter paper on Rotax 912,915 engines. I think they have them very well sorted. No carbon stuck to the filter can.

Have never seen a heat shield for the oil filter on any 912,915 that i have serviced. They all have similar exhaust manifolds.

You need an effective Heatshield between the exhaust and the Oil filter. Nev

It wouldn't matter if the spinifex was green or dry, I've seen green patches of spinifex sending flames 6m into the air. We often camp in spinifex country and take a lot of care to contain the fire because once ignited there's no stopping it. It would make a very bumpy landing area too.

Appears that he had the plane for 2? years. Had a RPL but no navigation endorsement and then took it more than 25nm for maintenance. The navigation endorsement covers weather, terrain and route planning for exactly this scenario. This is pretty blatant stupidity and not the first or last time this will occur.

B737, classic version obviously 😉😉

A tangential thinker is someone whose thought process is characterized by a tendency to veer off-topic and fail to return to the original point. This can manifest as a complete loss of goal-directedness, where the speaker's response may be grammatically correct but lacks coherence and logical flow. that describes me not someone with a revolutionary idea.😁

The discussion of engine and carb heat design should have been in a separate topic in the Engines and Props forum. It is not directly related to the Parafield accident.

Road motorcycles generally have paper air filters while offroad motorcycles generally use foam soaked in oil. I have seen thousands of motorcycles including hundreds at competition events. Over 40 years I have never seen a motorcycle air filter on fire.

That Tenzing-Hillarys airstrip at Lukla in Nepal is not something I'd like to visit. An EFATO there and you'd be unlikely to survive. No weather radar, no nav aids, and clouds that can sweep in in minutes, means VFR only there. https://www.himalayanglacier.com/facts-about-lukla-airport/ I'd guess a lot of PNG Highland strips aren't a lot different - apart from not even being sealed! I often wonder how they got the equipment and materials in there to build the runways. This a photo from WW2 (from "Pacific Wrecks") showing troops manhandling a small towed scraper through a C-47 doorway to build airstrips from scratch in tiger country.

You do realise they have layers of cotton between the mesh outer layers.

Cone air filters are used a lot on Rotax . They would be spark arrestors as well. If your aeroplane is shooting out 2 mt flames you might want to do a tune up😁

Wonder if there are applicable colour endorsements available?

There's a vid for that ... (Google Earth shows it as about 5,000' elev. around 50 km SSW of Grenoble) From the YT description: "La Salette is one of the most difficult and most technical airfields of the south Alps and few airmen venture there. Several accidents took place there, mainly because of side exits or too short landing, but there have never been deaths. Thus the main risk is to break some wood or to twist of sheet steel. The missed approach can be very late decided during flight, there is no effect of funnel as on other altisurfaces. We can decide even there once on ground if we arrive with too much speed at the top of the dome, which is shown in this video. The only difficulty in this case is to find the way to the axis of take-off in a place where the convexity of the profile leads to a very difficult visibility. The axis of landing is directed to 190 ° while the axis of take-off is 210 °. It is thus necessary in case of go around on ground, to turn at the top of 20 ° to the right if we do not want to break the plane (big slope to the left, bushes to the right!) to plan this eventuality, the mountain pilot will beforehand have taken a mark far off (summit) to facilitate this alignment. This video was shot in the morning of October 25th, 2017. We had left with my father this morning there for outdoor day mountain. The conditions being optimal this day there, my father wanted to make his first landing for La Salette by benefiting from my experience and from my friendly supervision. The approach was led well, but some kph of excess at the flare and a delay of application of brakes made us arrive too fast at the top of the dome. We shouted together "Go Around !" what proves that we were in phase. The fact of pushing the throttle control from idle to full gas all at once surprised the engine which began to suffocate, the full power returned only to the rotation. Incident to be meditated on the functioning of our engines (Continental O-200 on the speedjojo) which is not abnormal but which the brutal application of the throttle control under stress can engender." Some more tricky strips of the Southern Alps: https://www.youtube.com/watch?v=k8kI5PzzrzM

The Douglas AC-47 ("Puff, the Magic Dragon")

Nev I think most would understand that cool air is more dense therefore you can squeeze more into a confined space but we're talking about carburettor icing, something that Rotax seem to have less of a problem with than other engines in similar service. It has nothing to do with the fact that you brought it up even if you did appear a little rude in the manner you did so. What I'm suggesting is that Rotax may be utilising available heat to help prevent carburettor icing. If heat transfer from the airbox is the answer you'd get less heat at higher revs due to the more rapid airflow. Therefore performance at higher engine speed would be less affected. Once you reduce throttle and therefore airflow through the airbox incoming air temperature would rise effectively combatting carburettor icing.

I don't have carb heat on the 2 stroke but I keep the revs up on descent to avoid cold seizure and carby ice. Which is easy to do with draggy airframe.

Be careful Moneybox. For the most part, Rotax do not endorse "lagging" of the exhaust system. Targeted shielding seems to be more acceptable. I do a bit of both, with the emphasis on hose insulating, rather than exhaust. 😈

There used to be a saying: There are Old Pilots and Bold pilots but not many OLD, BOLD pilots. Also, EVEN if you do manage to get there, what example are you setting? Only GAMBLE when you can afford to lose. PPPP. Proper Planning Prevents Piss Poor Peformance.. Weather and Terrain and fuel, deserve your utmost attention no matter what you fly. SOME people are Unfit to be in charge of an aircraft. They identify themselves to the Observant, easily and usually come unstuck in a big way before long because nothing they are told SINKS IN. Nev

I have always thought the following. Rules for flying are serious because flying is so unforgiving. They are there to help prevent killing people in aircraft and on the ground, to penalise those who do not obey, and to help solve legal issues after accidents. Cheers.

While I wholeheartedly endorse the general thrust of your statement, I would point out that rules & regulations are not in place to prevent the stupid killing themselves, they are, in effect, there for the wise, who understand the reasons for and adhere to, the rules, thus preventing their untimely demise The stupid , the gung hoe (most of us have been there) unnecessarily risk their and the lives of others by ignoring the rules. This is as it has always been and will continue. as long as we remain the creature we are. 😈

No, it was a "Darwin Award" offence. Rules and regulations are in place to prevent stupid people killing themselves, and creating a huge mess for others to clean up, and adding serious levels of costs onto others.

In a previously edited post I said he should be jailed (if he was not already dead). This is pretty obvious poor decision making.