moroa

Yes Chris the 170D is certainly a nice aircraft and an improvement over the old one with the temporary mods . Jabiru should also be commended for their prompt action in rectifying the faults and the J160 does need full concentration when landing at ( or above ) MTOW. Also nice to chat with you briefly at the factory .Bob

at what altitude was that 134 kts tas recorded ??

bing carb

sonex 3300 owners regularily push the revs up at higher altitude and confirm TAS of up to 147 kts (170 mph) at aceptable fuel burns ,but most of there owners use either aerocarb or rotac TBI (not without there own problems either) these are posted on yahoo groups sonex talk.

jabiru j230 owners do not post as high TAS cruising at higher altitudes ,maybe not because the aircraft isnt capable of it, but probably because fuel burn is to high.

maybe the carburation could be improved ? ,jabiru have revised there jeting several times ,maybe the 50 year technology in the old marvel schebler carburetor of the lycoming/continental suits aircraft better?

http://www.airplanefactory.co.za/world/press.asp SOUTH AFRICANS fly round the world

but then this guy uses a bing carburetor in his rotax 912 & has just flown the pacific so it must be a good carb or he would of got wet on the california to hawaii leg ,a very impresive achievment.

would you trust the jabiru with your life & fly it around the world with 2 pilots, spend 5 days at oskosh, with only scheduled maintenance and only be away a MONTH could the j230 be economical enough on fuel to do it ??????

leaning at altitude

I agree with what you have said power drops off whith altitude, so you need to apply full throtle, or near to it so you stay off full enrichment ,which is for cooling (thats why they call it full throttle height) usually above say approx 6000 feet power will be below 75% thats what i do in a lycoming or continental you manually lean it and fuel consumption settles down to the same regardless of altitude for a constant power output

As you state power at 10000 feet is approx 63 % less than sea level (poh citabria ) so a 3300 jabiru would burn say 40 od litres/hr at high revs down low & 63 % of this is say 15 l/hr but this does not happen.

I have spent thosands of hours cruising at altitude in light twins we do this to get a high tas (because the air is thinner) for a constant fuel burn for that percentage power.

you are correct stating in the fixed pitch propellar revs are higher (say leave the revs at max in a constant speed propellar all the time) to achieve percentage power but it should not make that much difference the mixture should be approx 15/1 this clearly does not happen if you where to cruise a bing carbed jabiru at say 2850 rpm at 10000 feet why?

high fuel flow

Why at altitude as you say power out put is low are people reporting at full throttle fuel flows of aproaching 30 litres per hour. If you assume that the SFC of most engines is .5 lb/hp/hour you can estimate the actual horsepower being produced by looking at the fuel burn.

full throtle hight

so are you saying as long as you do not use full throthle at say 10000 feet it will lean it out ok? how near to full throtle could you run it?, as it would be well below 75% pwr?

Has any one fitted vgs examples please

full throtle at 10000 feet??

can any one confirm fuel burn at altitude & high revs if it is significantly above low level normal cruise 2800 rpm (75% pwr) the bing carb obviously does not compensate properly for aircraft aplications ?? coments please ,,in lycoming or continental operating at altitude the hanbook recomends leaning ,and in many probaly millions of hours world wide fuel consumptin at a constant percentage power (even if rpms increase as in fixed pitch props ) only rises a little.

I would go as far as saying the bing carb does not lean enough with altitude<<<<<<

J230 at altitude say at 8500 feet 2900rpm or higher ( remeber percentage power will drop off with altitude so you will have to rev higher to get 75% pwr) what true airspeed (TAS) will it do??

cofg ???

J230 foward c of g limit is 10 percent of MAC (mean aerodynamic chord ) all other jabs is approx 20 percent when flying without balast or bags is it to nose heavy ie full aft trim on aproach can you take your hands off the controls or will it race away????

I have not seen any other aircraft with a limit this far foward it seems a compromise in design to me any coments out there?

try turtlepac.com 20 litre bladder jerry can you would not need apump as you could plumb it in & squeeze it or roll it up to push the fuel out:laugh:

measurements please

could someone measure from the front of the seat to the door post (hinge) & also from the front of the seat to the firewall please:help:

j170? 4 cyl

does the 4 cyl instilation have same high temp problems?????

turtlepac.com

try turtlepac big buddy:laugh: