Cruise Speeds

[rassy7]

I've been fighting the "cruise speed" battle for a while now and am still unable to find an answer. I compile my flight plans with AI Flight Planner -- the newest version, like 1.6 or something. The cruise speed listed for aircraft like F-16s and F-15s is usually around 650 or 700. When they fly in FSX, however, they don't come close to those speeds averaging more like 250-320. I've read about the "37-minute problem" AIFP discusses extensively and have tried to test my way around it, compiling flight plans RAW and doubling the aircraft cruise speeds both in the CFGs and in AIFP's aircraft modifier. I am unable, not matter how I compile flight plans, or what the cruise speed says, to get any AI aircraft to fly faster than about 300 during any phase of flight.

Has anyone else experienced this "cruise speed wall" I've run into or have any solutions?

Thanks for your help,
~Josh

[Firebird]

In controlled airspace, basically below FL100, then the aircraft are limited to 250kts. I don't know if its applied across the board but definitely in areas that are basically all controlled airspace. e.g. the UK.

[mikewmac]

I've been fighting the "cruise speed" battle for a while now and am still unable to find an answer. I compile my flight plans with AI Flight Planner -- the newest version, like 1.6 or something. The cruise speed listed for aircraft like F-16s and F-15s is usually around 650 or 700. When they fly in FSX, however, they don't come close to those speeds averaging more like 250-320. I've read about the "37-minute problem" AIFP discusses extensively and have tried to test my way around it, compiling flight plans RAW and doubling the aircraft cruise speeds both in the CFGs and in AIFP's aircraft modifier. I am unable, not matter how I compile flight plans, or what the cruise speed says, to get any AI aircraft to fly faster than about 300 during any phase of flight.

Has anyone else experienced this "cruise speed wall" I've run into or have any solutions?

Thanks for your help,
~Josh

Josh,

Be careful when monitoring cruise speed that you know which air speed you are observing. IAS or Indicated Air Speed is much lower than TAS or True Air Speed at higher cruise altitudes. The cruise speed setting in the aircraft.cfg file is set in KTAS and if you are monitoring the air speed of an AI aircraft in KIAS you will never observe an air speed at higher altitudes as high as the cruise speed setting in the aircraft.cfg file.

Mike

[rassy7]

Good point Mike, thanks.

Also, I'll try getting some traffic routes set up to move above and beyond controlled airspace and see if I can get a reaction.

~Josh

[rassy7]

Just out of curiosity ... have either of you actually seen an AI traveling faster than like 320 or so in FSX?

~Josh

[Firebird]

I am purely an FS9 man myself, but regularly I get aircraft at M0.9, above FL100.

[mikewmac]

Just out of curiosity ... have either of you actually seen an AI traveling faster than like 320 or so in FSX?

~Josh

Josh,

My AI FDE's for many of the various MAIW fighters allow them to cruise at FL280 at ~500-600 KTAS in FS9. I have never used FSX so I have no first hand experience, but I would assume that their cruise speeds would be similar when used in FSX.

Mike

[rassy7]

Ok ... all of what you're saying makes sense, I just need to try these tests at different flight levels I think. I measure the airspeed a few different ways. I check via my own HUD when flying in formation, which I realize measures indicated air speed, but I also measure them with traffic map from the SDK which I think measure KTAS.

I'll try the same tests I've been running in uncontrolled air space and at higher altitudes and see where that gets me,

Thanks again for all your help!

~Josh

[Graham King]

I think the "Cruise Speed" can be considered the speed over the ground or Ground Speed. It can also be known as True Air Speed or TAS if there is no wind. Add a TAS to the panel of the aircraft you are following with and see what the result is.

From what I remember at 35000 ft an airliner cruises at 450 kts, ground speed, but approximately 250 kts IAS, Indicated Air Speed the speed you see displayed on the instrument panel.

[dk1213]

I have the same problem, however, for some odd reason when I use my Northrup Grumman F-5 as AI it cruises at 550kts. Everything else is slow at around 320 - 370kts, with the exception of the f-5.

[Firebird]

I have seen that sort of thing before. its normally due to using a non-AI aircraft and its FDE as AI.

An example of this, in the early days, before MAIW, I tried to use the Alphasim Jaguar for AI. It was crap as it sped everywhere at over 600kts.

Would I be right in thinking that this is your problem with the F-5?

[dk1213]

yea Steve right again, I am using flight one's air traffic fx to fly formations with nick's ai and other MAIW planes - but you can import regular planes into ai and thats the only time you will see erratic behavior.

[Firebird]

I thought that it might be.
The simple trick here is that you have to mod the flyable aircraft to use an AI fde. Quite often its a case of using both the the .air file and the .cfg file, however it should be mentioned that the .cfg does need to keep certain characteristics of the original aircraft.

These would be the contact points, lights and views as they refer to the actual model. For the F-5 I would say use the default lear jet fde as a good starting point, its a close enough fit for that type. Now it may very well be a good idea to copy the F-5 folder to make a purely AI version, so that you can still fly the other one, but remember that the individual titles of the aircraft have to be different from the original otherwise the AI engine won't know which aircraft to use.

Oh and of course remember to sim= lines in the config to point to the new .air file.

Have fun playing around with that.

[dk1213]

I tried to make a duplicate of my Iris Tigershark for AI with no luck. Can you explain to me how to do it?

[Firebird]

I thought I had done, but obviously not well enough.
Did what I wrote not make sense, or is there one particular part that you are stuck on?

[dk1213]

So sorry to be a noob like this. I am learning so much so fast, at 29 you think I can grasp some of this stuff but honestly it gets overwhelming. I took the IRIS Tigershark, copied the file, used ai editor to swap the air files and changed config titles and they did not show up when I imported them with air traffic fx.

[Firebird]

That's OK, we all started somewhere.
So you started with a copy of your TigerShark folder. You copied across the learjet air file.
Then you best you rename your TigerSharks aircraft.cfg to aircraft_f20.cfg .
Then copy across the aircraft.cfg from the lear folder.

Now you amend the aircraft.cfg, copied across, by replacing all the fltsim entries in that with the entries from the aircraft_f20.cfg.
Once you have done that, you will need to amend the sim= entries to pick up the lear sir file, not the F-20 one.
Then amend all the title= entries so that they are different from your flyable entries. Simply starting with 'AI_' will suffice.

Now comes the slightly trickier bit. You need to copy across the contact points, lights and views sections from the aircraft_f20.cfg file replacing the ones in your new aircraft.cfg.
Why? because you are using the same model and those parms will not change as they are linked to the model.

Now providing that you have a traffic bgl compiled to use the title of AI TigerShark it should appear.