Next big question ....Fuel Heat?

[Guest sphing]

Hello,It seems to me that modeling th fuel temp and fuel heat switches are features that are not supported directly by FS2002. I can't fin any parameters to read or control these fucntions.Any recommendations on how to best code this in XML? what is the best way, using FS variables, to simulate fuel tempurature and a fuel heating system?Here is some basic data I have been given by a DC-9-41 pilot and the attachedment is my current XML code set for the DC-9 fuel system (..and also a screenshot):1)"The fuel heat is used if we have fuel temp below zeroat this stage. Sometimes also before takeoff during thewinter, if we have a fuel temp below zero during taxi.When the fuel heat is pressed, the fuel temp will riseto about +30 degree, then return slowly. The fuel heatwill be on for 60 seconds when the switches are activatedmanually. In auto mode the heat will be on for 60 secondsand of for 30 but this mode was never used." - Stellan Hilmerby2)"The fuel heat switches are placed on the overhead panel(engine starter panel). The purpose of the heater systemis to obtain a fuel filter temperature sufficiently highto prevent the freezing of any moisture in the fuel."- Stella Hilmerby3)"Fuel temp is dependant of outside temp. After fuelingis done the temp is something like 10-30. Then the tempwill drop during cruise often -10 after two hours offlight. When we read the approach checklist we alsocheck the fuel temp." - Stellan Hilmerbyhttp://forums.avsim.net/user_files/31938.jpg

[Guest]

Hi,You're right, there is no required variables in FS by default, so you'll need to use custom local variables for them.We did a simple simulation of fuel heaters for our YS-11. It simulates the accumulation of ice crystals in the fuel filters and after reaching a certain level the fuel flow is cut off. The accumulation rate is dependent on the outside air temperature and it has some randomization in it. The system in the YS-11 is not as complex as the one on the DC-9, but perhaps it will give you some ideas how to proceed.Please feel free to check our gauge code. You can download the YS-11 package from http://www.alliedfsgroup.com. Or if you'd like just the latest panel/gauges, you can get them from here: http://http://www.cc.jyu.fi/~ekkaihla/manual/Best regards,-Esa

[phjvh 0]

Hi,Because there are no a:var's and k-events, i use ambient temperature with a correction for altitude.So temp. remains above -30 degrees C.If temp. drops below -30, very seldom!, pressing "fuelheatswitch" adds another 10 degrees, so temp. returns to good values.If you don't (eicas message) and wait to long, the penalty is an engine failure and then you have to make a "free fall" to an airlayer with higher temp.All pretty unrealistic, but just fun.Jan"Procul Negotiis"