Hi , I wondered if anyone could help me out, i use the great free software Plan G, to make flight plans etc in FSX. I have made several tanker patterns, to practice my A/A refueling in the Superbug and despite setting the speed for the tanker at 250 kts and it showing in the flight plan legs at 250 kts, the tanker flies in FSX at 400 kts, which is too fast for refueling really.I am not sure if this an FSX issue or Plan G issue or a user issue.... Can anyone help?Cheers,Mark

Hi , I wondered if anyone could help me out, i use the great free software Plan G, to make flight plans etc in FSX. I have made several tanker patterns, to practice my A/A refueling in the Superbug and despite setting the speed for the tanker at 250 kts and it showing in the flight plan legs at 250 kts, the tanker flies in FSX at 400 kts, which is too fast for refueling really.I am not sure if this an FSX issue or Plan G issue or a user issue.... Can anyone help?Cheers,Mark

Only thing that comes to my mind is a workaround. I would test to change speed settings in the section [Reference Speeds] in the aircraft.cfg file. I don't know if it works, though.

Hi there,I always thought that the speed you enter into G-Plan was the cruiseing speed for the plan or i'm i reading the question wrong...Dave...

No I'm pretty sure fs just uses that number to calculate where the airplane should be when you load it, after that it's all the performance of the ai plane itself.

I had to play with the reference speeds to get it precisely at the desired speed.Problem is, we have ground speed, true airspeed and Indicated airspeed. Took experimenting to find the appropriate value.Here is the line currently in my config as I tweaked for different speeds - it's probably going to vary with altitude.cruise_speed = 358 //<-AI cruise 358 Knots True (KTAS) = 250 KIAS at FL250this is what I use on KC135 at the moment.Loyd

Manual says that the Plan-G uses true airspeed not indicated.

Surely the speed of your AI aircraft is nothing to do with Plan G? How could it be, it has no method to command the performance of AI, it just reads their position and places an icon on the map, updated at an interval which you can set in the Plan G options.Sorry if I am wrong, and I await confirmation with interest.Could you use FS Recorder to record the flight path of your Tanker (you'd need to fly that pattern yourself in the Tanker whilst recording it) and then get FS Recorder to play back your flight whilst you fly the Superbug and formate on it for refuelling?I'm an ignorant old glider pilot, I know Naaaathing, but hope that might help.GLIDERDRIVER

Surely the speed of your AI aircraft is nothing to do with Plan G? How could it be, it has no method to command the performance of AI, it just reads their position and places an icon on the map, updated at an interval which you can set in the Plan G options.Could you use FS Recorder to record the flight path of your Tanker (you'd need to fly that pattern yourself in the Tanker whilst recording it) and then get FS Recorder to play back your flight whilst you fly the Superbug and formate on it for refuelling?GLIDERDRIVER

When I fly tanker live for multiplayer, I would set auto throttle at 250When I record, I fly A/T at 250 so playback is 250 (kias)As best I remember,When I drop a tanker into a flightplan (SDK: Create AI, use xxxx.pln with 25,000 altitude) I found by experiment that Cruisespeed in cfg needs to be 358 for the AI to fly at 250kias at FL250so I conclude that config cruisespeed (True airspeed) is what the AI would try to maintain even if the IAS shows a different speed. I'll try the same flight at different altitude to see if Indicated is different. I used PG to set up the initial flight route but didn't fiddle with speed in the planner, only adjusted cruisespeed afterward to insure that the resulting flight was 250kias at altitudeLoydedit update: FL250, cruisespeed 358 yielded 239 indicated...this is what displayed on labels and info text (KIAS)in real world, wouldn't this also be affected by air temp and density so would change with season/date. I'll try that also. I suspect it's going to be different.

edit update: FL250, cruisespeed 358 yielded 239 indicated...this is what displayed on labels and info text (KIAS)in real world, wouldn't this also be affected by air temp and density so would change with season/date. I'll try that also. I suspect it's going to be different.

UPDATEcruis speed 358kts at 25000' registers 239KIAS (June)Unchanged aircraft at 12000' registers 299KIAS (June)Unchanged aircraft at 12000' registers 298KIAS (January)So season doesn't appear to matter but altitude obviously does.Looks like one would need to find or make a table of TAS vs IAS plotted against altitude to set it up in advance.Loyd

Now i am really confused.... !! So, if I add those lines to the .cfg file of my tanker Loyd, are you saying it will fly at 250 kts at approx 20,000ft? Does 250 kts in Plan G equate to 390 kts airspeed at 20,000ft ? Otherwise how can I alter the speed the tamker cruises at? I dont mind tweaking the cfg file as i only ever use it to refuel from..