scavenger,
With a "CONFORMING ENGINE" it is as easy as…….level out in the cruise, (close your eyes for about 3 seconds while quickly moving the mixture leaner. As soon as you feel the deceleration - stop. Open eyes.
Now I do it in the climb if I want to with my eyes open, not because I am any genius but once you have done it 10-20 times you can do it repeatedly. Once you know your calibrated butt is accurate it is hard to get it wrong. If you move the mixture too slowly and/or have your eyes open you will not sense the deceleration and will miss the sweet spot known as best BSFC.
This technique works at 500' and WOT/max rpm or at FL150/xxxx RPM.
Now the hidden question you ask is how do I do it sans an EMS. Well take a carby O-320 RV6 that a Airline guy I know owns, no EMS but we are 100% sure the engine is a conforming one. guess what, the Big Mixture Pull works every time. And yes that is a carby engine.
Of course if the engine was not conforming, it would not do that nicely and you would know.
Let me be clear, the ROP pilot takes off after an annual and the injectors have been out, and it is a TC/TN engine, he flies home with one cylinder leaned out to a ROP setting that is driving that cylinder head pressure and temp up through the roof, and it runs smooth as a babies bottom. No EMS therefore he never knows. But if he was familiar with the BMP technique, the first thing he would do after maintenance is do an orbit over the field and a BMP, if it played nice he would go home either LOP or ROP (both are valid if done right). If there was a F/A ratio issue he would certainly discover it and land asking the LAME to fix it.
Of course having an EMS would make the diagnosis a LOT easier.
So there ya go……ROP pilots actually need engine monitors more than LOP pilots. Add to that once LOP by BMP method, you can't hurt any engine, period. But if you are an uncertain red knob fiddler you can.
Two last points;
A: The APS class is for piston pilots and LAME's. Yes a lot of LAME's have had many great learning experiences, David Paynter from Brisbane Aero, the late Steve Hobson from Bankstown, and about 15 more I can think of.
the class is NOT a LOP class…..I will say that again, it is NOT a class about flying LOP, in fact it would be about 10% maximum. The science of combustion taught with real in cylinder engine dyno data, how that relates to what you see on an EMS, how to manage for best speed/range or whatever in all types of flight mode, how to diagnose the EMS data (and this is where 100% of pilots and LAME's learn the most) and it is where we spend the most time. Plus quite a number of life saving diagnosis in flight topics, and how to save a fortune on maintenance bills by doing the right things at the right time and saving hours of chasing problems rather than going straight to them.
This last paragraph is what the original poster was really thinking I bet. I now know who he is…..good student and great guy
B: Andrew Denyer, Leisa and myself have yet to take a profit from APS and in fact personally we are out of pocket. We leave any residual funds to ensure the classes are fully funded despite the costs and it is not cheap to put on.
While I can't speak for John George and Walter, I do know that we did the sums one day sitting down with a cold drink in Tennesse or Louisianna, and the hourly rate would be something like a dollar or less. I doubt George has ever banked a cheque, John used to send them. Think he gave up. When you realise the motivation is more about better education with science and the safety outcomes that delivers, then you might understand that profit is not even a thought let alone a motivation.
While I think of it, imagine the satisfaction when you get an email explaining how the lessons learned in class saved a family from grief because they diagnosed and dealt with a problem before it got them over the top of the Rocky Mountains, or even the many smaller helped solve a problem that saved wasting several thousand dollars in chasing it down. Last year I had a lady (over 65) who did the course discover a whole bunch of defects, some her LAME was dismissive of and telling her the EMS was just scaring her. He was wrong, she was right and the things I found were a disgrace. She saved herself thousands, and maybe her life one day as a result.
That folks makes it all worth the hundreds of hours we put in for no financial gain.
When the master class is released we will reinvest in that for the benefit of our students…..engine monitor diagnosis torture is the best way to describe it
IFEZ…..if we could explain that in one internet post, do you think anyone would ever come to let alone pay for a 2.5 days brain strain?
Seriously, I do not care whether you fly a Briggs and Stratten powered ultralight or a Chieftan……..the theory is all the same. If you really want a better explanation send me a PM with your phone number and I will happily chat for a bit….typing the Q&A's back and forward will kill my keyboard
