RFguy

I'm in the process of buying an Archer. The 8.5:1 Lyco has a MOGAS STC, which sort of surprises me because I would have thought that only 7:1 Lycos would tolerate the ULP quality issues. So they must be tough......and 8.5:1 isnt all that high. The engine is originally factory specified for 91/96 MOGAS (~ 91AKI) which is something like (AUstralia) 94RON from memory (will check) but the heads do get hot. enemy #2 of course is the higher vapour pressure. but clearly, with STC issued, not seen as too much of a Vapor lock problem , as least evidently... low wing, aux fuel pumps . maybe in warmer weather if you do not use the fuel pumps on takeoff there is a low pressure in the lines == vapour bubble issue which could cause trouble at the wrong moment just after takeoff... Potential for trouble also at high DA.....It might be something I only use in winter..... . See my earlier posts of symptoms of vapour in the fuel lines- cycling fuel pressure over 20-200 seconds I'll dig up the STC and take a read to what was done. and if there is any specific placarding. And remember MOGAS does NOT mean 'automotive bowser dispensed'.....

The other thing is, in the ACT, there is a new rule that requires medical practitioners to (compulsory) advise the ACT motor vehicle regulator (vehicle license) , or CASA (air) if their patient has anything out of tolerance. IE the patient has no say in it. This has caused an exodus of ACT heavy vehicle licensed drivers apparently, and medical doctors dont like it either.

Starter pulls about 150A at 10V for a 3300 with good compressions. at oil and engine cold @ 18 degC.

yeah but you didnt give those in the same post, you had different posts with different things in them ! still, overall sounds like good performance.

it's a good video.... Looks bad for Continental, good for Lycoming. and less than ideal for continental company behaviour.

And , a fully charged , unloaded (but not on the charger) 12V lead acid AGM battery at 50 deg C would read about 12.15V where as at 25 deg C would read 12.6V Any attempt to charge it at high temperature, with a non temperature compensated charger would very much overcharge it

Well... you mentioned "23.3 in". was that manifold pressure , or just the pressure altitude ?

ahh so that's wide open throttle then (IE manifold pressure is approx same as (static) air pressure) ? or is that Manifold pressure gauge ? .

Jabs are air flow forward facing and jabs dont have any problems with their fuel delivery.

What type of battery is it and what is the terminal voltage ?? If it has not been below 10.5V for any sustained period (weeks) , its probably fine. a footnote- those deciding on battery location, consider heavy FRP non conductive cover over the terminals- consider what might happen in an accident and have say, an aluminium panel or member squash onto the battery terminals. Now you have a fire. I have seen MANY experimental aircraft have this flaw (in my opinion) , and some factory 24- aircraft.

https://www.recreationalflying.com/topic/38878-jab-down-chinchilla-airport-260223/?do=findComment&comment=542249&_rid=11148 " the seatbelt wad torn from the fuselage and a hole remains where it was bolted in. "

Dont get too wound up about the exact flapped stall speed, measuring airspeed accurately at high AoAs is difficult ... (not to mention dependence of AUW weight, CoG location, ) Sounds good Skip, at least writing it out here can provoke your brain a bit as your write. My observation is that flaps on some aircraft dont really change stall speed much , more used to increase decent rate and increase drag and tweak the attitude a bit. There are others here that can offer far more. Which way is the aft trim required at 'high speed cruise' ?

arm yourself with a good stethoscope (1.5m length of soft silicone (or not too hard PVC ) tubing jammed into your ear hole) (note that's EAR hole) and some soapy water (cylinder -head interface leaks / intake gasket/exhaust couplings - Jabiru)

being a 19- experimental aircraft with you as the builder affords you a high degree of flexibility in ways to kill yourself of course. That is the big plus of 19- changing the reflex / static pos of any of the control surfaces (aielerons) or high lift devices (flaps) will have a relatively big change to stall characteristics, all types of provoked stalls of course. If you have plenty of altitude, I'd suggest you write up a good barrage of repeatable stall testing . That thing has a big rudder and you wont load it tail heavy so recovery with correct technique and altitude is likely. There WOULD BE a flight test regime from the manufacturer. Maybe test against that ?

My observations are there is a fair spread of leakdown results in the manner at which they are done. They can can be certainly made to look good, so best (most applicable) method as as described in the relevant engine manual from the manufacturer. Depending on the ailment, some will be worse just before or just after TDC (maybe ring related) , some will be worse static at TDC (maybe valve related) . some will be worse during rocking the crankshaft around TDC (maybe ring related) , there are other variations (cylinder -head interface leaks etc, cracks etc) AND COMBINATIONS !

Oh yeah . I see .I didnt see those other pictures. my bad I see someone has stuck it into a db https://aviation-safety.net/wikibase/308770 Jabiru are going to have to do something about seat belt anchors failing, that's another I have heard about from a factory aircraft. *unacceptable*

and for logbooks and maintenance, convention (and you really do want to stick to convention for such a critical engine health vital sign) is to write down the figure of the two gauges in psi. The type with a % gauge requires assumptions and assumptions are no good.... Buy the one used by aircraft technicians, has correct orifice, and correct gauging.

jesus.... Barto, was it a 'LSA55 ? hopefully there will be an investigation and AD on the seatbelt restraints. -glen

Then.... by the book, the pilot would be charged with manslaughter whether he was licensed & current, and the aircraft was maintained per rules ..or not. ----Since it meets the definition , purely and simply of manslaughter. Now, what actually happens in a court - the reckless attitude will not help him defend this charge.

this one looks like a good option May be available locally , also. https://www.aircraftspruce.com/categories/building_materials/bm/menus/to/test_cylinders.html I have one of these https://www.aircraftspruce.com/catalog/topages/diffpresse3m.php I see they have one with the rotax plug thread https://www.aircraftspruce.com/catalog/topages/diffpress12mm.php

The ATSB report has a fair chunk of info in it.

I dont agree that the UBER example is relevant to this. The airplane SHOULD have had EXPERIMENTAL plastered everywhere,. Maybe the manslaughter charge is just pressure to get a plead of guity on everything else.

The manslaughter wont get up. it wasnt charter, pax tasks own risk in light airplane. The CASA admin charges will get up and they will throw the book at him.. aggrevated. he'll have to plead guity to all of them , since there is no contest.

mmm. I'd like you to locate the regulator, unplug from the harness , physically inspect the connector in situ, and replug it in snug. Also is your engine a Gen4 with the CB in series with the alternator stator ? anyway, buy a spare breaker . carry it . take a look at the wiring- make sure all plugs for instruments panel pushed home. Could be a bit of equipment got an overvoltage and decided to crowbar (puts a short on the bus) , maybe something not right in the regulator/alternator wiring.

There is no such thing as random for this . The total load all active should not trip the breaker. When you say just after startup- was this as you increased RPM so the battery voltage began to rise as the battery began to take charge ? Or before you went over 1500 RPM ? Roscoe, take a good look with glasses on and lots of light at the wiring you can see. Change the circuit breaker. See if it occurs again.