Correct lean

[kiri]

Hi: how do I know if fuel lean is set correctly according to altitude ? (flying Beechcraft Duke B60 V2)

Thanks for any help, kiri.

[Sentry_FiveZero]

Generally accepted practice is to lean until your begin to lose engine rpm, look at your EGT, and then go rich until your temp is 50 degrees lower than that.

 

 

Sent from my iPhone using Tapatalk Pro

[scottb613]

Hi Kiri,

 

Unfamiliar - but is that the TURBINE model ? If so - you don't lean turbines... I didn't think RA released a V2 on the piston ?

 

If it's the piston model - it should have an EGT Gauge - Exhaust Gas Temperature... You want to start pulling the mixture back - s-l-o-w-l-y - until you find the MAX EGT reading and the gauge starts falling off as you pull it further - this is the Lean Of Peak side (LOP) - and for our purposes - not where you want to run the engine... So start richening the mixture again until you find max - then keep richening it - Rich Of Peak side (ROP) - until you're passed max temp and you're around 100 degrees richer than the max - this should be your best power setting - since we're not paying for gas this should be fine... The actual temps don't matter - just that you're around 100 degrees richer than the max temp displayed - many gauges have a bug to mark the max temp point... Keep in mind you this will need to be modified any time you change altitude...

 

Regards,

Scott

[mallcott]

Hi: how do I know if fuel lean is set correctly according to altitude ? (flying Beechcraft Duke B60 V2)

Thanks for any help, kiri.

 

2 methods:

1: The `analyzed` method: Lean until peak TIT, then enrich back to 50 degrees rich of peak. Not 60. Not 40. Exactly 50

2: The `f**k it, I'm simming` method: Lean until peak fuel flow, then richen it a bit

 

I know of several real pilots, in real aircraft that use method 2... its only fuel money.

 

There is also Method 3: Lean to 50 degrees past Peak to a 50 degree lean of peak. This method usually demands highly accurate fuel injection and even more accurate measurement of cylinder temps and remains somewhat contentious:

http://www.gami.com/paulferraris_leanofpeaksaga.pdf