Ah thanks that’s great! Maybe you can also consider climb performance and flap drag. Regarding the latter: in the default model you’d need around 60% throttle (Manifold well into the green around 20 In) to keep 70-80 kts on a 400-600 fpm descent with full flaps. This seemed unrealistic to me so I arbitrarily lowered the flap drag. Would like to know if it’s ballpark or needs further tweaking…
Weight used: pilot 200 copilot 150 middle right 210 back left 180 fuel 67%.
weather dzb-sat 29c at the surface 22c at 5000ft
In climb I’ll have WOT - wide open throttle (29" and decreasing with altitude). After takeoff I climb at 100kts, do flap retraction, reduce rpm to 2600 then set up the flight director to nav mode and climb with FLC, then turn on the autopilot. I’ll set airspeed to 120kts (up to 140kts depending on how much airflow I need to keep the CHTs below 200c in climb) to at least above 6000’ cruise.
In the sim I am showing about 300fpm on average climb performance difference over my experience.
Reaching a low cruise for testing I set up a few situations
20" 2300rpm gives about the top of the white arc (124kts) clean, that is close. (its a good power setting for being vectored around at low altitude).
flaps approach, gear down, 15" and prop full forward in a 500fpm descend should get around 100kts, I’m getting 102kts.
flaps full, gear down, 20" and prop full forward in 500fpm descent should get around 90kts, I’m getting 92kts…
on to an ils approach on autopilot.
flaps app, gear down, 20" 2500rpm was about 125kts, in real life this would be closer to 117kts
flaps app, gear down, 15" 2500rpm was about 110kts, in real life this would be just shy of 100kts.
I usually fly 18" 2500rpm approach flaps and gear down for about 105-110kts.
The power feels pretty close, it might be the lift that feels just a smidge too much much or not enough drag clean.
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I will try this. I am finding that the stock plan achieves about 135 kts in cruise (4500’) with 23 in. mp and 2300 rpm. I think that it should be closer to 160 kts?
doing another flight and found a bit of a weird situation
WOT 22" 2500rpm @8500ft leaned to max fuel flow getting 164kts (I’d expect 168)
I pulled back the prop 22" 2300rpm and I get 161kts (I expect 166)
All good, but a little slower than book and what I expect, not by much
but then!
for fun I pulled the prop all the way back. it dropped to 1950rpm before settling at 2000rpm. It accelerated to 175kts (not realistic)!
all at 22"
2700rpm 166
2600rpm 165
2500rpm 164 (-4)
2400rpm 164
2300rpm 161 (-5)
2200rpm 161
2100rpm 167 lol
2000rpm 175 LOL
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Thanks for the tests!
From what I understand:
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overall very good, maybe the sim is slightly outperforming the real G36 (by less than 2%)
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there is a 300 fpm discrepancy between the sim and your experience in the G36? The sim is outperforming it’s real-world counterpart you mean? I tested for Vy of 100 kts @ 2700 rpm and full throttle, which pretty much fits the charts I used at sea level and lower altitudes. (As much as 1300 fpm at sea level under ISA conditions)
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Approach flaps need some extra drag/decrease in lift.
yes, the sim climbs better than real world, but I think the book outclimbs real world a little bit too.
check your cruise values again, especially above 8000ft, they are maybe 3-5kts slow
try climbing at recommended climb, not just Vy to altitude
i’d try increasing drag more than lift on approach flaps, but yes.
you are refining what is already great work!
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As for this behaviour I have no idea what is going on. There is only so much I can do by changing the cfg files and I’m not sure whether this can be easily changed or is a more fundamental problem like the mixture in this sim.
I’m also trying to get this model to work in the SDK aircraft editor but to no succes so far. Now I have to restart the sim everytime I make a small change to a cfg file. The increase of app flap drag is an easy one luckily, but I’ll try to fix the other issues as well. If anyone (more familiar than I am with fsx/msfs flight/engine models) has any ideas please let me know!
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What cruise speeds are you getting post modification? I’m cruising at 15500 at a paltry 134 KIAS. From what I can tell this is far too low. MP seems really low at 17” as well. Am I doing something wrong?
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134 KIAS is approx 174 knts TAS, which is probably fairly close to correct.
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Vx climb is just used for initial climb out if you need to clear obstacles (or a noise abatement area for certain aircraft) correct? Would you use flaps for that or just the take-off?
I’ve also modified the G36 and ended up reducing the flap drag a little because with full flap I found that I couldn’t accelerate on approach if needed especially when I increased the gear drag, which seems way too low because extending the gear at the default drag value didn’t effect the aircraft speed.
Checking the POH, standard ISA conditions, the manifold pressure at 16000ft, 2500 RPM is 16.3, so the sim is a little high.
Thanks for checking that for me. I doubt I was in ISA conditions, that could be why it was a bit high. Without more accurate MP reading I wouldn’t be able to tell you for sure though.
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Thought I would jump in here since you guys are doing some great testing and tweaking for the G36. I flew for Beechcraft Corporation for about 13 years, so lots of hours spent flying new Bonanzas and Barons, KingAirs, etc. Couple things that might help to make sure everyone is on the same page. Make sure to set up the airplane as follows:
Max weight (3650 lbs)
Standard day (15° C)
No winds / clouds / icing
Depart from Sea Level airport.
Climb at 2700 RPM and 100 kts Indicated
Cowl Flaps closed (Probably no effect in the sim)
I know normally you climb faster and and at a lower RPM, but that is how the flight manual numbers are done in flight test. The book data is spot on to what the airplane does. There is some minor variation due to a correction factor from when they removed the altitude compensating fuel pump and didn’t flight test the new numbers, but that is outside the scope here.
As far as leaning goes, it may be best to turn on Auto-Mixture in the sim. I don’t know how else to get a level comparison without an accurate Garmin fuel flow / CHT indication. Attached are a couple pages from the flight manual in case you want to compare. Let me know if you have any technical questions, etc.
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Thanks for the charts. I’ll see if I can replicate some numbers and get back to everybody on how the mod is comparing to real world climb performance numbers over the next hour or so
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Good point about the mixture as it’s a bit messed up in the sim. But then if what jonasbeaver says it right about the prop control that could be throwing things off as well.
If anyone wants a full copy of the POH all the Bonanza ones are available here - https://www.aircraftassociates.com/model-pohs/
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its not a turbocharged aircraft, as you get much above 8000ft the speed starts falling off.
The book says indicated you should get 127 indicated 153 true with a max manifold pressure of 16.1 @ 15000ft
Best speeds for a non-turbo piston are 6000-10000 depending on the airframe and engine, the bonanza loves 7-8000
Working on all the permutations is gonna take me another few hours but I’ve got half the data as of now.
I may be wrong, but based on how I’ve gathered my data, shouldn’t I interpret the climb chart according to the one below, rather than the one you provided? Or do I need to retake my ground school? 
Excel sheet to follow, based on the climb characteristics we’ve all been debating/discussing. Early indications are telling me auto-mixture on/no mod may be okay, but it’s still early.
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Are you building this upon my mod? If so, we can maybe combine them rather than have two separate mods. Maybe we can make a git repository too?
Are you using the aircraft editor btw? I couldn’t get this to work…
Both yes and no. I’m compiling data with and without your mod, as well as with and without auto-mixture. I’ll have the results within the next hour or two.
EDIT: No, all testing is being done in-game. I haven’t used any debug software/aircraft editors, nor would I know how to as of yet.