Solo student pilot in Cessna crash at Parafield walks away. 05/01/26

[facthunter]

IF a Valves stick or drops in it doesn't Matter. Nev

[facthunter]

To the 618. That is Odd and I can't see why it would BE. You have EGT gauges. Are the readings similar? The Main jets affect full and near full throttle. Nev

Edited yesterday at 02:00 AM by facthunter
typo

[BrendAn]

7 minutes ago, facthunter said:

To the 618. That is Odd and I can't see why it would BE. You have EGT gauges. Are the readings similar? The Main jets affect full and near full throttle. Nev

Surprised you haven't heard of that before. It's well known  . My egts both run around 600 

[BrendAn]

13 minutes ago, BrendAn said:

Surprised you haven't heard of that before. It's well known  . My egts both run around 600 

For the Rotax 618 UL, the main jets typically differ between the PTO and MAG carburetors, with common stock settings being #135 (PTO) and #145 (MAG), though these can change with altitude, intake silencers, or specific setups, with larger jets (like #160/#170) often needed at lower altitudes or with silencers to prevent running too lean, a common issue for this engine. 

Key Jetting Information

• Standard/Altitude > 5000ft: #135 (PTO) & #145 (MAG).
• Sea Level/With Silencer: #160 (PTO) & #170 (MAG).
• Why Different Sizes? The 618 uses two different carburetors, and they require different fuel flows for optimal performance,

[facthunter]

The 618 is not a very common Motor so why would I Know? I know it had problems with Crankshaft breakages and we are Going back a Fair way.

 Tuning, If you do it Properly you COULD end up with varying settings. Depends on how well each CYLINDER IS Pumping (Gas flowing). get it Leans there's a Hole in the  Piston dear Lisa, a hole. Nev

[BrendAn]

2 minutes ago, facthunter said:

The 618 is not a very common Motor so why would I Know? I know it had problems with Crankshaft breakages and we are Going back a Fair way.

 Tuning, If you do it Properly you COULD end up with varying settings. Depends on how well each CYLINDER IS Pumping (Gas flowing). get it Leans there's a Hole in the  Piston dear Lisa, a hole. Nev

there are lots of 618s around, still a lot flying now.  i thought you worked on most  aircraft engines. they have 2 different carbys.

good for 1000 hrs plus flown by the book .   crankshaft breakage probably happened with cold siezure, not  a common problem.

[turboplanner]

3 hours ago, Blueadventures said:

What fuel in use and method (Carb or injected)?

Methanol/Acetone and Carb. You can also get a backfire with Injected.

The "belching flames" were not relevant. 

When the backfire occurs, it lights up whatever type of fuel has soaked into K&H type filters and lights up the impregnated oil the filter material, causing a vertical fire if stationary, or wherever the wind flow sends it.  

[BrendAn]

8 hours ago, T510 said:

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

heard of the memphis belle.    i will call the xair the taco bell

[BrendAn]

19 minutes ago, turboplanner said:

Methanol/Acetone and Carb. You can also get a backfire with Injected.

The "belching flames" were not relevant. 

When the backfire occurs, it lights up whatever type of fuel has soaked into K&H type filters and lights up the impregnated oil the filter material, causing a vertical fire if stationary, or wherever the wind flow sends it.  

 people say its dangerous for 9 series rotax to have carbys mounted on top of the engine yet when do you ever hear of any catching fire.

about as often as you hear about them back firing. 

[turboplanner]

11 minutes ago, BrendAn said:

 people say its dangerous for 9 series rotax to have carbys mounted on top of the engine yet when do you ever hear of any catching fire.

about as often as you hear about them back firing. 

What would make an installed carburettor catch fire?

 

Back firing is usually due to maintenance errors, and incorrect throttle use, turning the ignition on, and off when running. The old 1920s cars had manual distributor advance-retard and hoons would build up to speed then pull on full retard and back off the throttle and the engine would backfire until advanced again.

 

In an aircraft you only ever need to have one backfire. It's how lucky you feel I guess.

 

[Thruster88]

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.

[turboplanner]

2 minutes ago, Thruster88 said:

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.

The potential for fire is not about K&N filters in particular; just any air filters which use oil impregnation and have no flame shielding.

 

We do know about it; I've personally seen about a dozen over the years. In cars on the ground there's no real problem. I've seen fires snuffed out  with fire extinguishers, bags and in one case hand-fulls of sand by half a dozen people.

 

[BrendAn]

45 minutes ago, turboplanner said:

What would make an installed carburettor catch fire?

 

Back firing is usually due to maintenance errors, and incorrect throttle use, turning the ignition on, and off when running. The old 1920s cars had manual distributor advance-retard and hoons would build up to speed then pull on full retard and back off the throttle and the engine would backfire until advanced again.

 

In an aircraft you only ever need to have one backfire. It's how lucky you feel I guess.

 

please stick to aircraft or find a car forum

[turboplanner]

1 minute ago, BrendAn said:

please stick to aircraft or find a car forum

If you don't understand the principle, you can just read along; I know it's hard for some to understand it's the engine we are talking about, not the car.

[BurnieM]

21 minutes ago, turboplanner said:

The potential for fire is not about K&N filters in particular; just any air filters which use oil impregnation and have no flame shielding.

 

We do know about it; I've personally seen about a dozen over the years. In cars on the ground there's no real problem. I've seen fires snuffed out  with fire extinguishers, bags and in one case hand-fulls of sand by half a dozen people.

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.

 

Edited yesterday at 06:46 AM by BurnieM

[BrendAn]

7 minutes ago, turboplanner said:

If you don't understand the principle, you can just read along; I know it's hard for some to understand it's the engine we are talking about, not the car.

 who cares that you could make a 1920s car backfire.   

 i used to have respect for you but not after the shit you said about me earlier. accusing me of being on here with different names.

 

 

Edited yesterday at 06:51 AM by BrendAn

[Thruster88]

Turbo, there is perhaps some differences between race cars built by amateurs running methanol, hot cams, wild ignition timing and a rotax or Lycoming. A lycoming with a straight pipe makes almost no sound due to very mild cam timing and overlap.

 

There is also the possibility that race car engines get turned backwards during a spin, the is would lickly cause fire to come out the wrong place.

Edited yesterday at 06:54 AM by Thruster88

[turboplanner]

1 hour ago, Thruster88 said:

Turbo, there is perhaps some differences between race cars built by amateurs running methanol, hot cams, wild ignition timing and a rotax or Lycoming. A lycoming with a straight pipe makes almost no sound due to very mild cam timing and overlap.

 

There is also the possibility that race car engines get turned backwards during a spin, the is would lickly cause fire to come out the wrong place.

One of them was a Horwood Bagshaw saw engine so not a race car built by amateurs running methanol. 

Most of the others were not race cars built by amateurs running methanol.

 

Do you really think an engine turning backwards backfires as a result?

 

It's worthwhile doing some reading about what causes backfires.

 

It's also relatively easy to take fire prevention measures with the system and that's worth a read also.

[facthunter]

Get Near a Merlin with a few revs on and repeat that. ON Load an Open AERO Engine exhaust makes Plenty of Noise. Plenty of People Lost their Hearing ( Including ME. Never Heard of any race engines Getting turned Back wards in any situation  and I've had a lot to do with them. It's extremely Unlikely.

 Turning the Ignition OFF and then Back ON will result ina Lot Of Mixture ending  in the exhaust and Muffler will explode and make Lots of Noise and EASILY Produce A Long Flame Out the tail pipe and scare the $#!t out of everybody.

  BACK Firing is when the Mixture in the intake and  supercharger Ignites/ explodes and Subjects things to VERY High Pressure. Superchargers Fly Off the Block Car Vee Block s split. Con rods get shortened etc. High Pressures force Valves off their seat and subject the Engines to Loads they Cannot Take.. They May not Fail straight away But an Overstressed Part is a damaged part.

[Moneybox]

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, 

[facthunter]

My reply has too many FACTS in it for you does it? What's personal in it FFS.  It took Me a great effort to type it.  Where else are People going to GET this stuff? The MISinformation  was going to a High Level. It's IMPORTANT INFO . Where is it  WRONG? Nev

[facthunter]

And it's NOT really off the topic of the thread Engine related. Safety. BAK,. Nev

[red750]

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.

[facthunter]

 Carry on in Blissful Ignorance. Less than Normal power May easily have been a factor, Drift is NOT always BAD. Don't kill good discussions because a few feathers get ruffled. Any abnormal Running or vibration should be Investigated even IF it appears to Have come good.  It's AN aeroplane. Nev

[red750]

Not saying that your discussion is wrong or not worth pursuing. What I'm saying is that in respect to this particular accident, you are creating unproven assumptions to support your narrative. The students lack of experience may have resulted in him not having the peripheral awareness of the speed if the ground rising to meet him resulting in the bounce.