To add a turbocharger to an aircraft...

[PilatusTurbo]

Do you just change that entry in the engine section of the plane, and increase its Manifold Pressure limit to something realistic like 36? Or is there more to it than that? I would also add a touch of extra weight, to simulate having a bit more hardware attached to the engine.

I'm just wondering if it really is this simple. I'm doing Air Hauler up out of Valdez, and my flagship could really use tougher lungs for those 13,500 feet flights. :d :ernae:

[warchild]

Do you want the short answer or the long answer??
The short answer is yup, adding a turbocharger is just that easy..
The long answer is, yup its that easy, but it isnt going to be realistic.
Let me show you...


This is from thee p-61 and its the lines in red we want to look at.

[piston_engine]
power_scalar=1.0
cylinder_displacement=155.555560
compression_ratio=6.300000
number_of_cylinders=18
max_rated_rpm=2700
max_rated_hp=2250
fuel_metering_type=0
cooling_type=0
normalized_starter_torque=0.033471
critical_altitude=19000
fuel_air_auto_mixture=1
auto_ignition=0
max_rpm_mechanical_efficiency_scalar=0.902
idle_rpm_mechanical_efficiency_scalar=0.67
max_rpm_friction_scalar=1.0 //0.83
idle_rpm_friction_scalar=0.83 //1.0
BestPowerSpecificFuelConsumption=5.567
supercharged=1 ; on/off
supercharger_boost_low_end=5.873 //multiplier on manifold pressure at low RPM
supercharger_boost_high_end=1.222 //multiplier on manifold pressure at high RPM
supercharger_power_cost=0.37 //percent of horsepower required to drive supercharger
detonation_onset=66.00
max_design_mp=54.25
min_design_mp=9.000000
emergency_boost_duration=1200.00000
emergency_boost_type=2
emergency_boost_mp_offset=8.865625
emergency_boost_gain_offset=1.851463
turbocharged=1

Ok.. first, it doesnt matter where in that mess you tell it it has a turbocharger.. What does matter, is the separate additions of supercharger and turbocharger.
First, the supercharger adds extra boost to the engine at all times while its running. It helps regulate airflow into the engine and makes it possible to fly above 13000 feet. It has an operational ceiling on this plane of about 21000 feet and a critical altitude of 19000 feet. That means that above 21000 feet it isnt doing an awful lot for the planes performance, and below 19000 feet it still isnt doing a lot for the plane, but at 19000 feet, the plane flies like a homesick angel.
The "Turbocharger" on the other hand, only provides emergency pressure to the engine allowing it to increase its manifold pressure beyond design limitations. it plays a very small part in the aircrafts over all functioning..
The trick is, setting the supercharger up properly. Its not an easy thing to do, even for an experienced mechanic ( who left my house after trying to help me shaking and in serious need of a drink ).

hope this helps
Pam

[PilatusTurbo]

Thank you, miss Pam. Very informative stuff. I did the basic mods to add a bit more 'ooompphh', but I'll probably research it more to learn how to get it right. I was worried the fuel flow scalars would be weird, but I was reading a great 185 PIREP, and they had an Air Research turbo in the plane. It really didn't drink too much more fuel, but gave the plane a nice kick. :ernae:

If anyone else would also like to add, more information is always a good thing. :ernae:

[warchild]

welllllll, if its omph your after then your going to need some tools..
One tool, if you can locate a copy, is AFSD or advanced flight simulation data. it uses FSUIPC to connect to fsx and fs9 and reports on a myriad of fuel engine/power control surface, speed and other data. The reason you need this is the real oomph is added not by changing in a part like the turbo charger, but manipulating the Min and Max rpm friction entries and the min and max mechanical efficiency entries in the above listed sub part of the config file..
The lower your maximum rpm friction the greater your horsepower
then higher your maximum efficiency numbers the higher your horsepower.

but i'd only recomend changing each by 0.01 at a time..

Pam

[SkippyBing]

First, the supercharger adds extra boost to the engine at all times while its running. It helps regulate airflow into the engine and makes it possible to fly above 13000 feet. It has an operational ceiling on this plane of about 21000 feet and a critical altitude of 19000 feet. That means that above 21000 feet it isnt doing an awful lot for the planes performance, and below 19000 feet it still isnt doing a lot for the plane, but at 19000 feet, the plane flies like a homesick angel.
The "Turbocharger" on the other hand, only provides emergency pressure to the engine allowing it to increase its manifold pressure beyond design limitations. it plays a very small part in the aircrafts over all functioning..
The trick is, setting the supercharger up properly. Its not an easy thing to do, even for an experienced mechanic ( who left my house after trying to help me shaking and in serious need of a drink ).

While true for the P-61 it's worth noting this isn't the case for all aircraft.

Most aircraft will only have a turbo or a super charger, not both, in which case they both do basically the same job of boosting the manifold pressure to maintain power as altitude increases. The supercharger is an engine driven compressor, hence the powercost= entry in the aircraft.cfg, the turbocharger (technically turbo supercharger) uses exhaust gas from the engine to drive a turbine which then drives the compressor.
Superchargers are always on and may have selectable speed ratios which allow the mass flow and the temperature of the charge air to be tailored to the operating altitude, the lower temperature of the slow speed charge air is worth about 400HP at sea level in the 2500HP Centaurus used by the Sea Fury.
In an aircraft turbochargers are generally always on as well, as opposed to cars where they cut out at low rpm when there isn't enough exhaust gas to keep them running.
In both cases there will be an critical altitude where working flat out the charger will be able to provide sea level pressure to the engine and no more, above that power starts to decrease. By extension if it can provide sea level pressure at 18000', it'll provide a lot more than that at sea level, this is an excellent way of destroying an engine. To avoid that with a supercharger you either give the pilot strict MP limits to fly to, or in something like the FW-190 or the Sea Fury the linkage in the throttle system automatically limited the MP to the max permissible irrespective of altitude. Hence in the Sea Fury opening the throttle fully will provide you with +9" of manifold boost up to ~24000', provided you change gear at 8000'.
With a turbocharger there's a waste gate which diverts the exhaust flow around the turbine, by linking that to a barometric capsule it can be designed to provide no more than maximum MP at any height up to critical altitude at which point the waste gate is closed and all the gas flow goes through the turbine. Obviously if the waste gate fails you have to manually limit the MP but that's not beyond the wit of man.

Most modern GA aircraft will have a turbocharger because they're lighter and simpler.

Worth noting you can write your own XML gauge to read the simulator values you want.

[Dangerousdave26]

Spot right on SkippyBing

It is also important to note that in order for the Turbo Charger to work in FS9 or FSX you must have

turbocharged= 1 // 0/1 off/on
max_design_mp= 80.000 // Manifold pressure
min_design_mp= 6.000 // Manifold pressure
critical_altitude= 28800.000 //Maximum altitude that turbo charger can increase Manifold Pressure to max_design_mp.

The supercharger line is FSX is FSXA only. It did not exist in FSX.

If you have turbocharged=1 set then the supercharger must be set to 0.

That also goes the other way if you have the supercharger on turbo must be off.