Thrust Scalar?

[DaveKDEN]

Does anyone know what the aircraft.cfg entry "thrust_scalar=" controls?

e.g.,
[jet_engine]
thrust_scalar = 1.0

 

[Kavehpd]

A simple search of the SDK:

Parameter that scales the calculated thrust provided by the propeller.

 

[DaveKDEN]

So, on a jet engine it has no effect?

 

[Kavehpd]

Type of the engine is irrelevant.

Thrust is calculated by various parameters that relate to specific types of engines. e.g. prop diameter, max rpm, etc. for turboprops, cylinder displacement or compression ratio for piston engines and so on.

thrust_scalar simply modifies the overall calculated value without the need to edit any other parameter. For example, if you want your turboprop aircraft to have twice the thrust it already has, instead of editing all the little values and parameters for your engine/propeller, simply edit thrust_scalar to read 2.0 instead of 1.0. That is all you have to do.

Unless you know exactly what you are doing and what values you need to fiddle with, thrust_scalar is the easiest way to modify the overall thrust of each engine.

 

[DaveKDEN]

Type of the engine is irrelevant.

Thrust is calculated by various parameters that relate to specific types of engines. e.g. prop diameter, max rpm, etc. for turboprops, cylinder displacement or compression ratio for piston engines and so on.

thrust_scalar simply modifies the overall calculated value without the need to edit any other parameter. For example, if you want your turboprop aircraft to have twice the thrust it already has, instead of editing all the little values and parameters for your engine/propeller, simply edit thrust_scalar to read 2.0 instead of 1.0. That is all you have to do.

Unless you know exactly what you are doing and what values you need to fiddle with, thrust_scalar is the easiest way to modify the overall thrust of each engine.

Excellent - thanks!

 

[fliger747]

I always reccomend Herve Sors AFSD utility to find out what your plane is doing performance wise. It will tell you in real time hundreds of factors, for instance, HP delivered and thrust, prop blade angles and efficiency etc. a great help for any fiddling

Cheers. tom

 

[Portia911]

Type of the engine is irrelevant.

Thrust is calculated by various parameters that relate to specific types of engines. e.g. prop diameter, max rpm, etc. for turboprops, cylinder displacement or compression ratio for piston engines and so on.

thrust_scalar simply modifies the overall calculated value without the need to edit any other parameter. For example, if you want your turboprop aircraft to have twice the thrust it already has, instead of editing all the little values and parameters for your engine/propeller, simply edit thrust_scalar to read 2.0 instead of 1.0. That is all you have to do.

Unless you know exactly what you are doing and what values you need to fiddle with, thrust_scalar is the easiest way to modify the overall thrust of each engine.

Ok, I like the sound of this (last sentence), but having attempted cfg tweaks with only limited success, I'm also tempted by the minefield if information that is on the site Tom refers to - well he doesn't link to the site, but I this is where he's pointing: http://www.aero.sors.fr/
So Tom, would you have any tips on the best airfile editor for a fdx newb?
Thanks :salute:

 

[Kavehpd]

Ok, I like the sound of this (last sentence), but having attempted cfg tweaks with only limited success, I'm also tempted by the minefield if information that is on the site Tom refers to - well he doesn't link to the site, but I this is where he's pointing: http://www.aero.sors.fr/
So Tom, would you have any tips on the best airfile editor for a fdx newb?
Thanks :salute:

I'm getting a virus/malware alert for that website. Sounds like my type of geeky software.

AirED is a freeware AIR file editor. Should be on FlightSim or Avsim. But as far as I know, CFG overwrites most of the AIR file entries and data in FSX. Not all of it though; I'm not exactly sure which ones. There is not much info on AIR files in the SDK unfortunately.

I also forgot to mention earlier, this "scalar" concept is pretty much the same for all other parameters. For instance, if you want more or less wing lift, instead of modifying all the tiny details of the wings (shape, size, angle, etc.), simply modify "lift_scalar". Think of them as a bunch of extremely useful and time saving shortcuts.

 

[mal998]

This taken from the FSX SDK:

[jet_engine]
The thrust_scalar parameter scales the calculated thrust for jet engines (thrust taken from the [TurbineEngineData] section).

As it relates to [Propeller]
thrust_scalar
Parameter that scales the calculated thrust provided by the propeller.

 

[hschuit]

Yves Guillaume created a document about the FDE and AIR file: "Flight Dynamics in Microsoft Flight Simulator". It is available in the AVSIM Library as fs_flight_dynamics_v1.0.zip (1.2 MB)

Besides AIREd, Aircraft Airfile Manager (AAM) v2.2 is a very good AIR file editor (created by Karl-Heinz Klotz). The big advantage of AAM is the graphical user interface to edit curves like record 1506.

The AAM Manual can be found HERE

View attachment 80168

 

[fliger747]

Yep, Aircraft Airfile Manager is about the best as one can change the various graphs using base ten entries. These tables are actually arrays in hex decimal.... Another useful one is Aired, which easily allows one to set two airfiles sided by side in text format and copy and paste entries from one to the other. Useful sometimes to take something from another plane or model that you have done before as a first order approximation.

Hrve's site can be found in about the first one or two Google entries...

The way I work is to get the HP correct and then adjust the airplane drag to arrive at correct performance. AFSD is useful to check both power and performance. Drag is best adjusted in the CDO line in the primary aerodynamics, for fast and high fliers Mach drag is also adjusted via a table.

lots of fun! T